The truth about TAVI/ TAVR


It looks like the rest of the medical community is finally speaking up about the overuse and safety issues of TAVI/ TAVR for aortic stenosis, but it’s still few and far between – and in specialty journals…  But in the same week that Medscape, and the Heart.org reported on a newly published article in the British Medical Journal on the overuse of TAVI therapies, and the need for earlier diagnosis and treatment of Aortic Stenosis – the Interventionalists over at the Heart.org (a cardiology specialty journal)  have published a series of articles promoting / pushing the procedure including an article entitled, “The TAVR Heart team roles.”

JAMA recently published a paper by Robert Bonow and Chintan Desnai, discussing the benefits, risks and expectations with TAVI.  This paper discusses the very real need for clinicians to address heightened patient expectations regarding TAVI as an ‘easy’ alternative to surgery.

TAVI is vastly overused – Reed Miller, The Heart.org

Here at Cartagena Surgery – we’ve been doing our own research – contacting and talking to a multitude of practicing cardiologists and cardiac surgeons to get their opinions – in addition to reviewing the latest data.

In related news, a review of the latest research on the ‘transcatheter’ valve therapies demonstrates considerable concern: including data on peri-valvular leaks as reported in the last national TAVI registries in Europe and in the US:

The incidence of  paravalvular leaks  after TAVI is extremely high  ( > 60%)

• It is technically challenging today to quantify these leaks.

• Most of them are quoted “mild”, but more than 15 % are estimated  “moderate” and “severe”.

• In > 5% of patients, the peri-valvular or valvular regurgitation grade increased significantly over time.

• there is no significant difference between Edwards SAPIEN and Medtronic COREVALVE

As one cardiologist explained:

“Importantly, the thrombogenic potential of mild leaks was recently demonstrated by Larry Scotten ( Vivitro System Inc. Victoria, Canada). High reverse flow velocities expose glycoprotein GP Ib-IX-V  platelet receptors  to circulating Von Willebrand molecule with, as results, platelet aggregation and fibrin formation.  The incidence of brain spots and stroke after TAVI was of great concern in the PARTNER A and B studies.  Whereas, Aspirin is not mandatory  in  patients implanted with bioprosthetic valves,   Plavix +  Aspirin is recommended for all TAVI patients. The rationales of such therapy were not explained so far.”

Valve oversizing – a surgeon explains

“To reduce  these peri-valvular leaks , cardiologists tentatively use large valve size, up to 29-mm.  The very large majority of valve sizes used in conventional aortic valve replacement are smaller than 25-mm.  Oversizing may increase the risk of late aortic aneurysms (aortic rupture has been reported) [emphasis added].

Moreover, atrio-ventricular conduction may be impaired  with the need of permanent pacing. Poorer outcomes have been reported in patients when the need for permanent pacemaker occurs.

“As we like to say about clothes and shoes, you forget the price overnight but you remember the quality for ever . The price of TAVI may be cheaper but patients may experience inferior outcomes. In view of these results, using TAVI would not be appropriate for the great majority of  heart valve candidates.  Moreover trans-catheter delivery and sub-optimal fit are not likely to increase tissue valve durability…  and everybody knows that tissue valves are not enough durable for young adults and children.  TAVI is thus a suitable strategy only for the neglected population of high risk patients who are no longer candidates for surgery [emphasis added].

Worth pointing out again  that there would be no need for TAVI and long-term outcomes of patients would be much better if severe aortic stenosis were correctly managed at the right time.  Enclosed the recommendations of Robert Bonow   (Circulation, July 25, 2012) for early valve replacement in ASYMPTOMATIC  patients.  A large cohort of accurate biomarkers is available today for correct timing of surgery  and consequent prevention of  irreversible myocardium damage. In the study of Lancellotti (enclosed) 55% of “truly asymptomatic patients” with severe aortic stenosis developed pulmonary hypertension during exercise and had  poor clinical outcomes. The measurement of both mean trans-aortic pressure gradient and systolic pulmonary pressure, which are technically easy, rapid and with good reproducibility may improve the management of such patients.

These updates on the natural history of aortic stenosis illustrate the present paradoxical and intriguing  focus of the industry on an experimental procedural innovation for end-stage old patients when more efficient heart valves are today feasible and could be used sooner for the benefit of all patients .

Enclosed an article on The Need For A Global Perspective On Heart Valve from Sir Madgi Yacoub.

Additional Reference / supporting data:

Modified from  Ross J and Branwald E   (Circulation 1968 (Suppl): 61-67)

• The  incidence of stroke was 9% after TAVI in  the 214 patients of the enclosed study published last week in the American Journal of Cardiology. The incidence of stroke with TAVI was >  two times higher than with conventional surgery in the PARTNER study.  Pooled proportion of postoperative stroke was 2.4%  with conventional surgery  in the  large meta-analysis of patients > 80 years old (enclosed)

• Peri-valvular aortic insufficiency is observed in more than  60% of patients undergoing trans-catheter aortic valve replacement.  Moderate or severe aortic insufficiency was seen in 17.3 % of the PARTNER inoperable and high risk cohorts at 1 year.  They have been reportedly associated with dyspnea, anemia,  cardiac failure and diminished survival. Most interestingly,  the FDA does not accept more than  1%   peri-valvular insufficiency in patients implanted with conventional prosthetic heart valves… The SJM Silzone mechanical heart valve was re-called  because of peri-valvular leakage rate of…  1.5 % .

• Traditionally, aortic stenosis involving a 2-cuspid aortic valve has been a contraindication to TAVI.  Of 347 octogenarians and 17 nonagenarians  explanted valves , 78 (22%) and 3 ( 18%) had stenotic congenitally bicuspid aortic valve, respectively.  Because the results of TAVI are less favorable in patients with stenotic congenitally bicuspid valves, proper identification of the underlying aortic valve structure is critical when considering TAVI in older patients . More than 50% of patients with aortic stenosis have bicuspid aortic valve and are not, therefore,  good candidates for TAVI. Most importantly, the great majority of patients with calcified stenotic  bicuspid aortic valves is  young ( < 60 years old)  and not candidate for tissue valve replacement.

•  The French Registry of trans-catheter aortic-valve implantation in high-risk patients was published in the New England Journal of Medicine on May 3,  2012. It reports  3195 TAVI procedures during the last two years at 34 centers.

The mean age was 83 years.  The incidence of stroke was 4.1%.  Peri-prosthetic aortic regurgitation was 64 %. The rate of death was 24% at one year. At the same time, the meta-analysis published in the American Heart Journal reports 13,216     CONVENTIONAL AORTIC VALVE REPLACEMENT in patients > 80 years old.    The rate of death was 12.4%  at one year,   21.3%  at 3 years and  34.6%  at 5 years

 

Full references for works cited in text:

Bonow, R. O. (2012). Exercise hemodynamics and risk assessment in asymptomatic aortic stenosisCirculation 2012, July 25.

Lancelloti, P., Magne, J., Donal, E., O’Connor, K., Dulgheru, R., Rosca, M., & Pierard, L. (2012).  Determinants and prognostic significance of exercise pulmonary hypertension in asymptomatic severe aortic stenosis.  Circulation, 2012 July 25.

Takkenberg, J. J. M., Rayamannan, N. M., Rosenhek, R., Kumar, A. S., Carapitis, J. R., & Yacoub, M. H. (2008).  The need for a global perspective on heart valve disease epidemiology: The SHVG working group on epidemiology of heart disease founding statement.  J. Heart Valve Dis. 17 (1); 135 – 139.

Gilard M, Eltchaninoff H, Iung B, Donzeau-Gouge P, Chevreul K, Fajadet J, Leprince P, Leguerrier A, Lievre M, Prat A,Teiger E, Lefevre T, Himbert D, Tchetche D, Carrié D, Albat B, Cribier A, Rioufol G, Sudre A, Blanchard D, Collet F, Dos Santos P, Meneveau N, Tirouvanziam A, Caussin C, Guyon P, Boschat J, Le Breton H, Collart F, Houel R, Delpine S,Souteyrand G, Favereau X, Ohlmann P, Doisy V, Grollier G, Gommeaux A, Claudel JP, Bourlon F, Bertrand B, Van Belle E, Laskar M; FRANCE 2 Investigators. Collaborators (184). Registry of transcatheter aortic-valve implantation in high-risk patients. N Engl J Med. 2012 May 3; 366(18):1705-15 [full abstract below].

BACKGROUND:

Transcatheter aortic-valve implantation (TAVI) is an emerging intervention for the treatment of high-risk patients with severe aortic stenosis and coexisting illnesses.

We report the results of a prospective multicenter study of the French national transcatheter aortic-valve implantation registry, FRANCE 2.

METHODS:

All TAVIs performed in France, as listed in the FRANCE 2 registry, were prospectively included in the study. The primary end point was death from any cause.

RESULTS:

A total of 3195 patients were enrolled between January 2010 and October 2011 at 34 centers. The mean (±SD) age was 82.7±7.2 years; 49% of the patients were women.

All patients were highly symptomatic and were at high surgical risk for aortic-valve replacement. Edwards SAPIEN and Medtronic CoreValve devices were implanted in 66.9% and 33.1% of patients, respectively. Approaches were either transarterial (transfemoral, 74.6%; subclavian, 5.8%; and other, 1.8%) or transapical (17.8%).

The procedural success rate was 96.9%. Rates of death at 30 days and 1 year were 9.7% and 24.0%, respectively.

At 1 year, the incidence of stroke was 4.1%, and   the incidence of periprosthetic aortic regurgitation was 64.5%.

In a multivariate model, a higher logistic risk score on the European System for Cardiac Operative Risk Evaluation (EuroSCORE), New York Heart Association functional class III or IV symptoms, the use of a transapical TAVI approach, and a higher amount of periprosthetic regurgitation were significantly associated with reduced survival.

CONCLUSIONS:

This prospective registry study reflected real-life TAVI experience in high-risk elderly patients with aortic stenosis, in whom TAVI appeared to be a reasonable option.

Rutger-Jan Nuis, MSc,  Nicolas M. Van Mieghem, MD,  Carl J. Schultz, MD, PhD,  Adriaan Moelker, MD, PhD ,  Robert M. van der Boon, MSc, Robert Jan van Geuns, MD, PhD, Aad van der Lugt, MD, PhD,  Patrick W. Serruys, MD, PhD, Josep Rodés-Cabau, MD,  Ron T. van Domburg, PhD,  Peter J. Koudstaal, MD, PhD,  Peter P. de Jaegere, MD, PhD.  Frequency and Causes of Stroke During or After Trans-catheter Aortic Valve Implantation. American Journal of Cardiology Volume 109, Issue 11 , Pages 1637-1643, 1 June 2012 [full abstract provided].

Transcatheter aortic valve implantation (TAVI) is invariably associated with the risk of clinically manifest transient or irreversible neurologic impairment. We sought to investigate the incidence and causes of clinically manifest stroke during TAVI. A total of 214 consecutive patients underwent TAVI with the Medtronic-CoreValve System from November 2005 to September 2011 at our institution. Stroke was defined according to the Valve Academic Research Consortium recommendations. Its cause was established by analyzing the point of onset of symptoms, correlating the symptoms with the computed tomography-detected defects in the brain, and analyzing the presence of potential coexisting causes of stroke, in addition to a multivariate analysis to determine the independent predictors.  Stroke occurred in 19 patients (9%) and was major in 10 (5%), minor in 3 (1%), and transient (transient ischemic attack) in 6 (3%). The onset of symptoms was early (≤24 hours) in 8 patients (42%) and delayed (>24 hours) in 11 (58%). Brain computed tomography showed a cortical infarct in 8 patients (42%), a lacunar infarct in 5 (26%), hemorrhage in 1 (5%), and no abnormalities in 5 (26%). Independent determinants of stroke were new-onset atrial fibrillation after TAVI (odds ratio 4.4, 95% confidence interval 1.2 to 15.6), and baseline aortic regurgitation grade III or greater (odds ratio 3.2, 95% confidence interval 1.1 to 9.3).

In conclusion, the incidence of stroke was 9%, of which >1/2 occurred >24 hours after the procedure. New-onset atrial fibrillation was associated with a 4.4-fold increased risk of stroke. In conclusion, these findings indicate that improvements in postoperative care after TAVI are equally, if not more, important for the reduction of peri-procedural stroke than preventive measures during the procedure.

Sinning JM, Hammerstingl C, Vasa-Nicotera M, Adenauer V, Lema Cachiguango SJ, Scheer AC, Hausen S, Sedaghat A, Ghanem A, Müller C, Grube E,Nickenig G, Werner N. (2012).  Aortic regurgitation index defines severity of peri-prosthetic regurgitation and predicts outcome in patients after transcatheter aortic valve implantation.  J Am Coll Cardiol. 2012 Mar 27;59(13):1134-41. [full abstract provided].

OBJECTIVES:

The aim of this study was to provide a simple, reproducible, and point-of-care assessment of peri-prosthetic aortic regurgitation (periAR) during trans-catheter aortic valve implantation (TAVI) and to decipher the impact of this peri-procedural parameter on outcome.

BACKGROUND:

Because periAR after TAVI might be associated with adverse outcome, precise quantification of periAR is of paramount importance but remains technically challenging.

METHODS:

The severity of periAR was prospectively evaluated in 146 patients treated with the Medtronic CoreValve (Minneapolis, Minnesota) prosthesis by echocardiography, angiography, and measurement of the aortic regurgitation (AR) index, which is calculated as ratio of the gradient between diastolic blood pressure (DBP) and left ventricular end-diastolic pressure (LVEDP) to systolic blood pressure (SBP): [(DBP – LVEDP)/SBP] × 100.

RESULTS:

After TAVI, 53 patients (36.3%) showed no signs of periAR and 71 patients (48.6%) showed only mild periAR, whereas 18 patients (12.3%) and 4 patients (2.7%) suffered from moderate and severe periAR, respectively. The AR index decreased stepwise from 31.7 ± 10.4 in patients without periAR, to 28.0 ± 8.5 with mild periAR, 19.6 ± 7.6 with moderate periAR, and 7.6 ± 2.6 with severe periAR (p < 0.001), respectively. Patients with AR index <25 had a significantly increased 1-year mortality risk compared with patients with AR index ≥25 (46.0% vs. 16.7%; p < 0.001). The AR index provided additional prognostic information beyond the echocardiographically assessed severity of periAR and independently predicted 1-year mortality (hazard ratio: 2.9, 95% confidence interval: 1.3 to 6.4; p = 0.009).

CONCLUSIONS:

The assessment of the AR index allows a precise judgment of periAR, independently predicts 1-year mortality after TAVI, and provides additional prognostic information that is complementary to the echocardiographically assessed severity of periAR.

Gotzmann M, Lindstaedt M, Mügge A. (2012). From pressure overload to volume overload: Aortic regurgitation after transcatheter aortic valve implantation.  Am Heart J. 2012 Jun;163(6):903-11.  [full abstract provided].

Severe aortic valve stenosis is a common valvular heart disease that is characterized by left ventricular (LV) pressure overload. A lasting effect of pressure overload is LV remodeling, accompanied by concentric hypertrophy and  increased   myocardial stiffness. Transcatheter aortic valve implantation (TAVI) has emerged as an alternative to surgical aortic valve replacement for patients with severe symptomatic aortic valve stenosis and high surgical risk.   Although TAVI has  favorable hemodynamic performance, aortic valve regurgitation (AR) is the most frequent complication because of the specific technique used for implantation of transcatheter valves.

During  implantation, the calcified native valve is pushed aside, and the prosthesis usually achieves only an incomplete prosthesis apposition. As a consequence, the reported prevalence of moderate and severe AR after TAVI is  6% to 21%,  which is considerably higher than that after a surgical valve replacement. Although mild AR probably has minor hemodynamic effects, even moderate AR might result in serious consequences. In moderate and   severe  AR  after TAVI,  a normal-sized LV with increased myocardial stiffness has been exposed to volume overload. Because the noncompliant LV is unable to raise end-diastolic volume, the end-diastolic pressure increases, and  the  forward stroke volume    decreases. In recent years, an increasing number of patients have successfully undergone TAVI. Despite encouraging overall results, a substantial number of patients receive neither symptomatic nor prognostic benefits from TAVI.   Aortic valve regurgitation has been considered a potential contributor to morbidity and mortality after TAVI. Therefore, various strategies and improvements in valve designs are mandatory to  reduce the prevalence of AR after TAVI.

Walther T , Thielmann M, Kempfert J, Schroefel H, Wimmer-Greinecker G, Treede H, Wahlers T, Wendler O. (2012). PREVAIL TRANSAPICAL: multicentre trial of transcatheter aortic valve implantation using the newly designed bioprosthesis (SAPIEN-XT) and delivery system (ASCENDRA-II).  Eur J Cardiothorac Surg. 2012 Aug;42(2):278-83. Epub 2012 Jan 30.  [full abstract provided].

OBJECTIVE

Transapical (TA- aortic valve implantation (AVI) has evolved as an alternative procedure for high-risk patients.  We evaluated the second-generation SAPIEN xt ™ prosthesis in a prospective multicentre clinical trial.

METHODS

A total of 150 patients  (age : 81.6;  40.7 % female) were included. Prosthetic valves (diameter :23 mm (n= 36), 26 mm (n= 57) and 29 mm (n= 57) were implanted. The ASCENDRA-II™ modified delivery system was used in the smaller sizes.   Mean logistic EuroSCORE was  24.3%  and mean STS score was 7.5 ± 4.4%.  All patients gave written informed consent.

RESULTS:

Off-pump AVI was performed using femoral arterial and venous access as a safety net.  All but two patients receivec TA-AVI, as planned.  The 29-mm valve showed similar function as the values of two other diameters did.  Three patients (2%) required temporary bypass support.

Postoperative complications included renal failure requiring long-term dialysis in four, bleeding requiring re-thoracotomy in four, respiratory complication requiring re-intubation in eight and septsis in four patients, respectively.

Thirty day mortality was 13 ( 8.7%)  for the total cohort and 2/57  (3.5%) receiving the 29 mm valve respectively.   Echocardiography at discharge showed none or trivial incompetence (AI) in  71%  and mild-AI in 22% of the patients.  Post-implantation AI was predominantly para-valvular and > 2+  in 7% of patients.  One patient required re-operation for AI within 30 days.

CONCLUSION

The PREVAIL TA multicenter trial demonstrates good functionality and good outcomes for TA-AVI, using the SAPIEN xt ™ and its second generation ASCENDRA-II™ delivery system, as well successful  introduction of the 29-mm  SAPIEN XT ™ valve for the benefit of high-risk elderly patients.

Subramanian S, Rastan AJ, Holzhey D, Haensig M, Kempfert J, Borger MA, Walther T, Mohr FW. (2012).  Conventional Aortic Valve Replacement in Transcatheter Aortic Valve Implantation Candidates: A 5-Year ExperienceAnn Thorac Surg.   July 19 2012  [full abstract provided].

BACKGROUND:

Patient selection for transcatheter aortic valve implantation (TAVI) remains highly controversial. Some screened patients subsequently undergo conventional aortic valve replacement (AVR) because they are unsuitable TAVI candidates. This study examined the indications and outcomes for these patients, thereby determining the efficacy of the screening process.

METHODS:

Between January 2006 and December 2010, 79 consecutive patients (49% men), aged older than 75 years with high surgical risk, were screened for TAVI, but subsequently underwent conventional AVR through a partial or complete sternotomy. The indications, demographics, and outcomes of this cohort were studied.

RESULTS:

Mean age was 80.4 ± 3.6 years. Mean left ventricular ejection fraction was 0.55 ± 0.16, and the mean logistic European System for Cardiac Operative Risk Evaluation was 13% ± 7%. Of the 79 patients, 6 (7.6%) had prior cardiac surgical procedures. Indications for TAVI denial after patient evaluations were a large annulus in 31 (39%), acceptable risk profile for AVR in 24 (30%), need for urgent operation in 11 (14%), and concomitant cardiovascular pathology in 5 (6%). Mean cross-clamp time was 55 ± 14 minutes, and cardiopulmonary bypass time was 81 ± 21 minutes. Concomitant procedures included a Maze in 12 patients (15%). Postoperative morbidity included permanent stroke in 2 (2.5%), respiratory failure in 9 (11%), and pacemaker implantation in 2 (2.5%). Hospital mortality was 1.3% (1 of 79). Cumulative survival at 6, 12, and 36 months was 88.5%, 87.1% and 72.7%, respectively.

CONCLUSIONS:

Our existing patient evaluation process accurately defines an acceptable risk cohort for conventional AVR. The late mortality rate reflects the advanced age and comorbidities of this cohort. The data suggest that overzealous widening of TAVI inclusion criteria may be inappropriate.

Industry fights back

Now it looks like Edwards Lifesciences,  the company that manufacturers the Sapien valve is speaking out to dispute recent findings that show TAVI to have less than optimal results.  Of course, the author at the site, Med Latest says it best, “Setting aside the conflict of interest stuff, which might be a red-herring, what we’re left with is a situation where evidence-based medicine, while being something all would sign up to, is not that straightforward.”


[1] Several cardiologists and cardiac surgeons contributed to this article.  However, given the current politics  within cardiology, none of these experts were willing to risk their reputations by publically disputing the majority opinion.  This is certainly understandable in today’s medico-legal climate in wake of widespread scandals and credibility issues. However, all quotes are accurate, even if unattributable with minor formatting (such as the addition of quotations, and paragraph headings have been added for increased clarity of reading in blog format.)  I apologize for the ‘anonymous nature’ of my sources in this instance – however, I can assure you that these ‘experts’ know what they are talking about.

  [All commentary by Cartagena Surgery are in italics and brackets]. 

Readers write in: TAVI


Thanks again to ‘Lapeyre’, who as it turns out is Dr. Didier Lapeyre, a renowned, French cardiothoracic surgeon credited with the development of the first mechanical valves.

Dr. Didier Lapeyre was gracious enough to send some additional literature to add to our ongoing discussions regarding severe aortic stenosis and TAVI/ TAVR therapies.  He also commented that the best way to avoid these ‘high risk situations’ is by earlier intervention with conventional surgery – something we discussed before in the article entitled, “More patients need surgery.”

He also points out that ‘elderly’ patients actually do quite well with aortic valve replacement and offers a recently published meta-analysis of 48 studies on patients aged 80 or older.

As readers know, on June 13, 2012 – the FDA ruled in favor of expanding the eligibility criteria for this therapy.  Previously, this treatment modality, due to its experimental nature and high rate of complications including stroke and serious bleeding, has been limited in the United States to patients deemed ineligible for aortic valve replacement surgery.

Now on the heels of the Partner A trial, in which researchers reported favorable results for patients receiving the Sapien device, the FDA has voted to approve expanding criteria to include patients deemed to be high risk candidates for surgery.  As we have discussed on previous occasions, this opens the door to the potential for widespread abuse, misapplication of this therapy and potential patient harm.

In the accompanying 114 page article, “Transcatheter aortic valve implantation (TAVI): a health technology assessment update,” Belgian researchers (Mattias, Van Brabandt, Van de Sande & Deviese, 2011) looking at transcatheter valve procedures have found exactly that in their examination of the use of TAVI worldwide.

Most notably, is the evidence of widespread abuse in Germany (page 49 of report), which has become well-known for their early adoption of this technology, and now uses TAVI for an estimated 25 – 40% of valve procedures*.  Closer examination of the practices in this country show poor data reporting with incomplete information in the national registry as well as a reported mortality rate of 7.7%, which is more than double that of conventional surgery.  Unsurprisingly, in Germany, TAVI is reimbursed at double the amount compared to conventional surgery**, providing sufficient incentive for hospitals and cardiologists to use TAVI even in low risk patients. (and yes, german cardiologists are often citing “patient refused surgery” as their reason, particularly when using TAVI on younger, healthy, low risk patients.)

In their examination of the data itself, Mattias et al. (2011) found significant researcher bias within the study design and interpretation of results.  More alarmingly, Mattias found that one of the principle researchers in the Partner A study, Dr. Martin Leon had major financial incentives for reporting successful results.  He had recently received a 6.9 million dollar payment from Edward Lifesciences, the creators of the Sapien valve for purchase of his own transcatheter valve company.   He also received 1.5 million dollar bonus if the Partner A trial reached specific milestones.  This fact alone, in my mind, calls into question the integrity of the entire study.

[Please note that this is just a tiny summary of the exhaustive report.]

Thank you, Dr. Lapeyre for offering your expertise for the benefit of our readers!

* Estimates on the implantation of TAVI in Germany vary widely due to a lack of consistent reporting.

** At the time of the report, TAVI was reimbursed at 36,000 euros (45,500 dollars) versus 17,500 euros (22,000 dollars) for aortic valve replacement.

For more posts on TAVI and aortic stenosis, see our TAVI archive.

References

Mattias, N., Van Brabandt, H., Van de Sande, S. & Deviese, S. (2011).  Transcatheter aortic valve implantation (TAVI): a health technology assessment .  Belgian Health Care Knowledge Centre.

Vasques, F., Messori, A., Lucenteforte, E. & Biancari, F. (2012).  Immediate and late outcome of patients aged 80 years and older undergoing isolated aortic valve replacement: a systematic review and meta-analysis of 48 studies.  Am Heart J 2012; 163: 477-85.

Update: Medicare to cover TAVI/ TAVR


In an update to a previous story here at Cartagena Surgery, in the attached article, “Medicare to pay for TAVI” from Medpage.com by Chris Kaiser, the guidelines for CMS payment for TAVI/ TAVR have been released.   These criterion include the restriction that only surgery ineligible patients be included and that implanting surgeons must participate in the TAVI registry.

More importantly, this criteria requires that TWO cardiac surgeons determine the patient’s suitability to withstand surgery versus TAVI.  This is a crucial requirement as we’ve discussed before, since only a surgeon can accurately decide/ predict how a patient might tolerate surgery.  (Multiple previous studies showed that primary care providers and cardiologists were poor judges of patient’s surgical risk. )  Also, the lack of this requirement in Europe has caused several ethical problems as interventional cardiologists began the widespread implantation of experimental technologies in lower risk patients (particularly in Germany.)

Will Medicare cover TAVI/ TAVR?


Updates to this story have been posted here.

In an article re-post from the Heart.org, Lisa Nainggolan discusses a recent memo issued by Medicare & Medicaid services (CMS) on potential coverage for TAVI/ TAVR.    This memo lays out the necessary criteria and conditions that must be met for CMS coverage.

Don’t have medicaid or medicare?  Well, the privately insured should still sit up and take notice:  CMS decisions usually set the pace for everyone else – meaning, if Medicare won’t pay for it – then Blue Cross, Anthem and most of the big private insurances won’t either.

CMS draft of proposed coverage – the Heart.org 

Lisa Nainggolan

Baltimore, MD – The US Centers for Medicare & Medicaid Services (CMS) has issued a memo detailing its proposed coverage for transcatheter aortic-valve replacement (TAVR) [1]. The move follows a request for national coverage determination (NCD) from the ACC and Society for Thoracic Surgeons (STS), made last September.

The memo—which is a draft and will be open for public comment until March 3—outlines the conditions under which the CMS will cover TAVR, also known as transcatheter aortic-valve implantation (TAVI), and follows hard on the heels of an expert consensus document on the new technology, published earlier this week.

An estimated 45 000 patients have received TAVI worldwide, with most procedures so far being performed in Europe. US approval of the Edwards Sapien valve at the end of last year means that the country must now gear up to introduce this technology nationwide, and the expert guidance has been designed to act as a roadmap for the rollout of TAVI in the US.

Five conditions must be met for Medicare coverage of TAVR

TAVR will be covered for the treatment of severe symptomatic aortic-valve stenosis only, says the CMS, and the following five conditions must be met:

  • The procedure is performed for an approved indication with a valve and implantation system that has received FDA approval for this indication.
  • Two cardiac surgeons have evaluated the patient’s suitability for open valve-replacement surgery. (traditional cardiac surgery)
  • The procedure is performed in a facility that meets certain requirements with regard to surgical and interventional cardiology expertise. In addition, institutions with prior TAVR experience must participate in ongoing trials or postapproval studies, and all centers performing TAVR must commit to the “heart-team” concept and enroll in a prospective national TAVR study.
  • TAVR must be carried out by sufficiently qualified and experienced physicians.
  • The treating team must participate in a national registry that enrolls TAVR patients and tracks the following outcomes: major stroke; all-cause mortality; minor stroke/transient ischemic attack; major vascular events; and acute renal injury.

For unlabeled uses of TAVI, the CMS proposes coverage only in the context of a clinical trial, for which it lists 13 conditions.

The CMS also indicates that it will not cover TAVR for any other indications not specified in its memo, nor will it cover the procedure in patients who also have concomitant conditions, including: mixed aortic-valve disease; isolated aortic regurgitation; untreated clinically significant coronary artery disease requiring revascularization; hypertrophic cardiomyopathy; echocardiographic evidence of intracardiac mass; significant aortic disease; and severe obstructive calcification or tortuosity of the iliofemoral vessel or small vessel size.

It’s a mixed win for American cardiologists and cardiac surgeons – and certainly opens the door to the expanded use of this criteria.  The good news is that CMS is taking the initiative to stem off a flood of inappropriate procedures.  The release of this memo, along with the recent publication of new guidelines re-affirming the role of CABG, and relegating PCI to specific circumstances  is almost certainly a response to the numerous scandals and allegations affecting cardiology in 2011 (and ongoing.)

Which hospitals should have TAVR/ TAVI programs?

This article outlines the basic requirements for a safe and successful TAVR program – including the minimum skill requirements for surgeons and interventionalists.

But I suspect – it won’t be long before more and more hospitals open their own programs.  This article highlights the financial gains for hospitals with TAVR programs.

TAVI/ TAVR and AVR in Arizona with Dr. Brady


Sat down today with Dr. Kevin Brady to talk about TAVI, or as he corrects me with a smile, TAVR (R is for Replacement).  Dr. Brady is a cardiothoracic surgeon, and one of the few currently performing TAVI/ TAVR here in Arizona.  As we’ve discussed before, I have mixed feelings on this procedure but have elected to provide the information here for my interested readers.

Dr. Brady shares many of my apprehensions, that the public will come to view this currently quasi-experimental treatment for very high risk, and inoperable patients with Aortic Stenosis as a ‘easy fix’.   We discuss this at length, and he reviews the current recommendations guiding the implementation of TAVR programs, and the TAVR registry with me.

As part of this discussion, I have invited Dr. Brady to write a short post here, explaining the procedure, patient selection criteria and other facts about TAVI/ TAVR.  With over 41 Core-valve implantations (since March 2011, as part of the Core Valve Pivotal trial) and seven Sapien valve implantations this month, he certainly qualifies as an expert on the topic.

Dr. Brady will be able to give readers a more in-depth perspective on this procedure.  As all of you know, I have taken a fairly cautious stance on this issue.  (I haven’t talked him into letting me observe yet, but I am working on it.)

Dr. Kevin M. Brady, MD

Southwest Heart & Lung

www.swheartlung.com

10930 North Tatum Boulevard, Suite 103

Phoenix, Arizona 85020

Tele: 602-263-7600

More TAVI news: the STACCATO trial halted, and data from PARTNER A.


The STACCATO trial of TAVI (percutaneous aortic valve implantation) was halted due to problems, and the new data from the PARTNER A trial is less optimistic than previously hoped.  More information from two articles published at the Heart.org (Heartwire.com) are re-posted below:

STACCATO: Transapical TAVI in surgery-eligible patients stopped due to adverse events
    Nov 10, 2011     Michael O’Riordan
San Francisco, CA– A study comparing the transapical approach for transcatheter aortic-valve implantation (TAVI) against conventional aortic-valve replacement surgery was stopped early due to an increase in adverse events, including an increased risk of major stroke and severe paravalvular leakage, in elderly patients eligible for surgery.

Dr Leif Thuesen (Aarhus University Hospital, Denmark), who presented the results of the STACCATO trial today at TCT 2011, said he is concerned about extending the indication of transapical TAVI to include patients who are candidates for surgery, especially given the increased risk of major stroke observed in this trial.

“There is no doubt there are patients who can’t be operated on, and they should be treated with TAVI,” Thuesen told heartwire. “But the patient who can be operated on—here, we should be very, very cautious. It’s the operable patients, the low-risk patients; they should not have the TAVI procedures, but that’s what is happening. We had one patient, for instance, who did not want the conventional operation, so he had the TAVI procedure in Canada. That’s how it is. Indications are slipping.”

The results of the study were presented during the late-breaking clinical-trials session, as well as during a morning press conference. After Thuesen’s presentation to the media, Dr Michael Mack (University of Texas, Dallas) pulled no punches in his criticism of the trial, saying the study was poorly designed and poorly executed. Mack said the trial was designed too optimistically and powered for event rates in the TAVI arm that were too low. Moreover, some of the events that stopped the trial, including one patient in the transapical-TAVI arm who died while on the waiting list for the procedure, skewed the results.

“I think there is some misinformation here, based on invalid trial design, that is likely to hurt the field,” Mack told heartwire.

The STACCATO trial

The STACCATO trial was designed three years ago and included elderly patients with valvular aortic stenosis who could be treated with surgery or transapical TAVI. Based on data from a surgery registry, they anticipated a surgical-event rate—defined as a composite of 30-day all-cause mortality, major stroke, and/or renal failure—of 13.5% and an estimated event rate in the TAVI arm of 2.5%. The study was stopped due to an increase in adverse events in the TAVI arm after the inclusion of 70 patients.

Indications are slipping.

Regarding the primary end point in the transapical-TAVI arm, there was one non-treatment-related death, one left coronary artery blockage, two major strokes, and one patient who had renal failure requiring dialysis. In the surgical arm, there was one case of perioperative major stroke. Other adverse events in the TAVI arm included a transient ischemic attack followed later with a major stroke, two perioperative cases of severe paravalvular leakage, one perioperative aortic rupture, one left main occlusion during balloon valvuloplasty, and one case of major bleeding.

Thuesen emphasized that the study was initiated three years ago and that the transapical TAVI devices at that time were relatively “unsophisticated” and not available in the full range of sizes now on the market. Moreover, he noted that the study investigators were optimistic about the success of TAVI in this population, especially given their absence of clinical events before the study was started, and for that reason they assumed an event rate of 2.5%, which he admitted was “completely wrong.” He noted that the trial began after investigators had performed approximately 40 transapical TAVI procedures.

To heartwire, however, Mack said the event rates were too low and that investigators should have estimated an event rate closer to 13%, similar to the event rate assumed in the surgical arm. Dr Joseph Bavaria (University of Pennsylvania, Philadelphia), on the other hand, saw a silver lining in the data, especially for surgeons. He said that the study shows the great surgical results obtained in patients with an average Society of Thoracic Surgeons (STS) risk score of 3.4.

Discussing the results and the stopping of the trial, Thuesen said that operators are now much better at handling paravalvular leakage, and newer devices might provide a much better fit into the aorta. Moreover, multislice computed tomography (MSCT) is able to provide better preoperative assessments over echocardiography, which was used in STACCATO. Still, despite the limitations of the trial, Thuesen said that in the current phase of development, transapical TAVI is likely inferior to surgery.

Asked about patients who want TAVI despite eligibility for surgery, Thuesen told heartwire that “we should try to persuade them to have surgery, no doubt.” Mack, on the other hand, said that on the front lines surgeons are forced to tell patients that their surgical risks are too low for TAVI and that surgery is the recommended treatment. “The patients don’t want what I’m selling,” said Mack.

[I completely disagree – of course patients want what Dr. Mack is selling – a quick, easy fix.. Who is he kidding??  That’s why it’s important that we make sure the procedure is safe before expanding the indications for TAVI. – Cartagena Surgery].

In a second article published in the last 24 hours over at Heartwire, results from the PARTNER A trial are also less optimistic than expected.
PARTNER QoL data hint transapical TAVI falls short of aortic-valve surgery
Nov 10, 2011     Shelley Wood
San Francisco – Quality-of-life (QoL) data from the PARTNER A trial should prompt a “rethink” of how many transcatheter aortic-valve implantations (TAVI) are performed via the transapical route, investigators say.

New QoL data released today at TCT 2011 show that while high-risk, surgery-eligible patients treated via a transfemoral route in PARTNER A reported substantial QoL benefits compared with surgery in the early weeks postprocedure, this was not the case for patients treated via a transapical route.

In fact, said Dr David Cohen (Saint Luke’s Mid America Heart Institute, Kansas City, MO), who presented the results, “for patients eligible only for the transapical approach, there was no benefit of transcatheter aortic-valve replacement over surgical aortic-valve replacement at any time point, and in fact, QoL tended to be better with surgical replacement both at one and six months.”

Life after TAVI

As previously reported by heartwire, PARTNER A tested the Edwards Sapien valve against surgery in high-risk patients, with all suitable patients randomized to TAVI undergoing a transfemoral procedure if appropriate and a transapical procedure if the patient was deemed unsuitable for a transfemoral approach. At one year, the transcatheter procedures were found to be noninferior to surgical replacement for the primary end point of one-year mortality.

For a number of secondary end points, TAVI and surgery were associated with differences in procedure-related complications and valve performance at 12 months, but the impact of these differences on patient QoL was previously unknown, Cohen said.

For the current analysis, Cohen et al measured QoL in PARTNER A using the Kansas City Cardiomyopathy Questionnaire (KCCQ), the SF-12, and the EQ-5D, with questionnaires administered at one, six, and 12 months.

For the overall comparison, researchers saw differences between TAVI and surgery at three months, but these had disappeared by six and 12 months. What was clear, however, was that there was significant interaction between the treatment effect and the type of TAVI procedure.

Cohen and colleagues therefore conducted further analyses of QoL according to whether patients had undergone a transfemoral or transapical procedure.

QoL improvements

“For the transfemoral group, the message is one that clinicians won’t find surprising,” Cohen said—these largely reflect the QoL findings from PARTNER B. The less invasive nature of the transfemoral [TAVI] procedure results in pretty important differences in QoL at one month, although by six and 12 months the patients have really come together.”

At one month, however, the improvement in QoL was meaningful—in line with about a one to 1.5 level improvement in NYHA class, Cohen said.

“But on the flip side, the transapical group was really somewhat of a surprise and showed certainly no benefit in terms of QoL of transapical over surgery at any time point, not a hint of a benefit. And for several different measures, [transapical TAVI] was actually doing worse. The trends were all toward worse QoL at one month with the transapical approach.”

At one month, scores were numerically lower for transapical TAVI compared with surgery across the various QoL scales used. At six months, this difference was actually “of borderline statistical significance” at p=0.04 for the primary end point (KCCQ overall summary). By 12 months, all differences disappeared.

The hardest cuts

His hypothesis, although it’s yet to be proven in this setting, is that healing from the medial sternotomy is actually easier and less painful than healing from the smaller, cosmetically “better” lateral thoracotomy used for transapical TAVI.

“A lot of what really hurts and impairs breathing and other sorts of things in these patients after cardiac surgery is motion of the wound. So if the wound is fixed, if the sternum is wired back together so it really can’t move, patients heal quite well, and it doesn’t cause a tremendous amount of pain once the first couple days are past. Whereas the smaller incision, the lateral thoracotomy, is always moving every time you take a breath. There is no way to wire that back together. I think it’s a more painful incision for patients to recover from.”

Cohen expects his presentation to meet with much debate, since it’s the first real suggestion that TAVI is not better than surgery, at least via the transapical route.

Indeed, in a morning press conference, surgeons Dr Michael Mack (Baylor Health Care System, TX) and Dr Joseph Bavaria (University of Pennsylvania, Philadelphia) both made the point that many of the US PARTNER centers actually performed very few procedures over the course of the trial, such that the transapical results truly represent a very early experience with this procedure. To heartwire, Bavaria noted that some of these transapical patients actually had complications that kept them in the hospital longer than expected. “I’d like to see the data from the continued-access registry, to see if those patients did better,” Bavaria said.

And Cohen agreed that centers in Europe, which have a longer history with these devices and procedures, may have found ways of improving patient recovery, involving better technique or using local anesthesia or nerve blocks, after transapical TAVI.

Already, however, while some registry data in Europe have pointed to much better results with a TA approach than those reported today, other European data have hinted that alternatives to the transfemoral route, such as the subclavian approach, may yield outcomes closer to those of the transfemoral route. So far, the Medtronic CoreValve is the only established TAVI device (approved in Europe) that can be implanted via a subclavian route. The CoreValve is still in the early stage of its pivotal clinical trial in the US.

Cohen acknowledged that done well, the transapical procedure is “slick, smooth, and quick,” but “we can’t assume just because the incision is small that the procedure is going to be easier to recover from.”

Asked what he thought the future of the transapical approach might be, Cohen replied: “I think it’s going to have a role, but I’m hopeful that this analysis leads us to reconsider the extent of that role. And for places that have access to multiple technologies for doing nontransfemoral procedures, this should be taken into account. And we may want to really rethink how much transapical we do.”

Mack, however, was less concerned, pointing out that the surgery group in PARTNER A did better than expected. “I think we cannot ignore [these results] and say there are not some concerns here . . . but I’m not as concerned about it as the data may [suggest].”

Still, the results should raise some eyebrows, experts speaking to the media seemed to agree. Dr Samir Kapadia (Cleveland Clinic, OH), speaking at the press conference, said, “This is a little bit shocking. This is a learning [moment]—it’s clear we have to improve the transapical procedure.”

Cohen disclosed receiving grant support/research contracts from Abbott Vascular, Boston Scientific, Medtronic, AstraZeneca, and Edwards Lifesciences and consulting/honoraria/speaker’s bureau fees from Daiichi-Sankyo/Eli Lilly, and Medtronic.

Both of these studies were presented at the 2011 TCT (Transcatheter Cardiovascular Therapeutics) conference in San Francisco – going on November 7th through 11th.

What does this mean for Transcatheter therapies such as TAVI?  It means we still have a LONG way to go before we can even begin to consider TAVI as a safe alternative to aortic surgery.  The key phrases of concern are ‘indications are slipping’ which means that everything that we’ve suspected/ feared is already occuring – patients are getting TAVI when they should have surgery – (presumably because it’s considered faster/ easier) and less resky – when as readers know: nothing could be further from the truth.
Here at Cartagena Surgery – we embrace technology, but only when it’s used appropriately.
Note:  Both of these studies have been re-posted verbatim – with no alterations in written content for the benefit of non-subscribers of cardiology publications. [Comments with article text are clearly delineated as my own, in brackets and italics: Cartagena Surgery].

It looks like TAVI is here.


The FDA recently approved the first TAVI device for aortic stenosis.   Currently the device is only eligible for patients who are unable to withstand surgery.   But who will end up making that determination?  The cardiologist who will be implanting the device?  At present – the company manufacturing the Sapien aortic device is recommending that patients be evaluated by a heart surgeon – but if this follows the typical course, I am sure that this recommendation will be abandoned as a matter of course.

Hopefully, the industry (interventional cardiology) will proceed cautiously, after being ‘omce bitten, twice shy” in light of the epidemic overstenting catastrophies.

For more on Aortic stenosis, TAVI and the overstenting controversies – look under the cardiology and cardiac surgery tab.

FDA and TAVI


Here’s the latest news on TAVI in the United States – and the status of the procedure, which is currently undergoing further evaluation by the FDA.

Here are some highlights from the article:

“In July, the FDA’s  Circulatory System Device Panel favored TAVI approval in the U.S. The  panel voted on three items, including: safety, effectiveness and whether  the benefits outweigh the risks. If the FDA accepts panel  recommendations, TAVI procedures would be available to U.S. patients.

However, CMS noted that it is aware of the high stroke and death rates associated with TAVI, and said that it remains concerned about adverse events that may occur, particularly when the procedure is performed by less experienced operators. Rates of stroke and death at 30 days were 6.7 percent and 5 percent, respectively, for those who received TAVI. At one year, these rates were 10.6 percent and 30.7 percent, CMS reported.”

As readers know; here at Cartagena Surgery – we’ve advised caution for the time being – until we have more long-term outcome data on transcatheter aortic valves.

However, after much consideration, and discussion with other people both in and outside the field of cardiac surgery – I have decided that I will begin interviewing and bringing more information about the procedure and providers performing this procedure in the USA.  Ultimately, while I may personally, (and professionally) feel that the TAVI procedure has not undergoing sufficient rigorous testing for my patients – I do not want to withhold information from them.

So, I have started writing and contacting providers to obtain more information about the physicians and medical centers performing this procedure. I will discuss these providers further in future posts.

Transcatheter Valve Therapy – (TAVI) overview


Here’s some follow-up information on the current recommendations / guidelines from the ACC (cardiologists) and STS (cardiac surgeons) on the use of TAVI or catheter-based therapies for the treatment of valvular disease.

Read it for yourself and let me know what you think, but I find it to be a nice, concisely worded document that clearly delineates and spells out the current role of TAVI therapies as a limited therapy for specific populations – at least until we have long-term outcome data.  (We can look to Europe and observe their outcomes, in part).

Not for young people, not for people who could withstand surgery (as determined by a surgeon/ sts risk calculator).  Not as part of an ‘easy fix’ mentality that winds up slapping us (and the patient) in the face a few years later.

Let’s hope that all the interventionists keep to the fundamental principles outlined here, as part of our commitment to patient care, safety and well-being.

Re-posted from Cardiosource.com

Title:         Transcatheter Valve Therapy: A Professional Society Overview From the American College of Cardiology Foundation and the Society of Thoracic Surgeons
        Date Posted:         June 27, 2011
        Authors:         Holmes DR Jr, Mack MJ.
        Citation: J Am Coll Cardiol 2011;Jun 27:[Epub ahead of print].
 Perspective:

The following are 10 points to remember about this expert consensus document on transcatheter valve therapy:

1. Transcatheter valve therapy is a transformational technology with the potential to significantly impact the clinical management of patients with valvular heart disease.

2. Although the initial experience is positive, evidence exists from only one randomized clinical trial in patients with aortic stenosis and one in patients with mitral insufficiency.

3. Adoption of these techniques to populations beyond those studied in these randomized trials, therefore, is not appropriate at the current time.

4. It will be important to establish regional centers of excellence for heart valve diseases. Criteria for centers performing interventional therapy in valvular and structural heart disease should be established, and the availability of devices and reimbursement for those procedures should be limited to those centers meeting those criteria.

5. The heart team approach should be used with formation of multidisciplinary heart teams within these centers led by primary cardiologists, cardiac surgeons, and interventional cardiologists.

6. Performance of isolated procedures without construction of a dedicated valve therapy program to encompass all aspects of care—including preprocedural assessment in common clinics, joint procedure performance, and common patient care pathways—is not recommended.

7. A national registry of valvular heart disease to perform post-market surveillance, long-term outcome measurement, and comparative effectiveness research should be established. This could be accomplished by linking the ACC’s NCDR® and STS clinical databases to the Social Security Death Master file and Centers for Medicare & Medicaid Services administrative databases in a national ‘research engine.’ This will, in effect, create a national registry of valvular heart disease.

8. Training and credentialing criteria for practitioners in this field need to be developed. Development of criteria for the formation of fellowship programs, as well as postgraduate training with appropriate experience for adequate patient care leading to guidelines for credentialing, is currently underway by multiple professional societies working together.

9. Interpretation of the current evidence by expert consensus documents and appropriate use criteria need to be developed.

10. With society leadership, multidisciplinary partnerships, and cooperation, a reasoned, balanced introduction of this new therapy can be accomplished.

Aortic Stenosis and TAVI: a new ‘stent’ scenario?


I am re-posting an article published in May on the heart.org by Reed Miller regarding the use of Transcutaneous Aortic Valve Intervention (TAVI).  TAVI is when a device is implanted in the cardiac cath lab (through an artery) to treat aortic stenosis.  Right now, this therapy is still in limited use in the United States, but is used more extensively in Europe where the guidelines are less restrictive.

I was a little disappointed here because I think some of his introductory language shows significant bias – but I think this article certainly adds to some of the discussions we’ve had here at Cartagena Surgery.  Even the title reflects a cardiology bias – cardiothoracic surgeons certainly aren’t the only ones who think we should be cautious about the overimplementation of new, experimental technologies in patients who are good candidates for existing (and proven) surgical treatments.   I would think that any prudent health care provider, or consumer would be hesitant to wholeheartedly embrace this therapy given the previous and recent cardiology lessons related to both carotid and cardiac stenting.

New technology is great – when it is selectively targeted to specific populations (high-risk surgical candidates such as extreme elderly (90+) or patients with multiple high risk co-morbidities) who would otherwise be ineligible for surgical intervention.  But let’s not put our patients at unnecessary risk by selling TAVI as an ‘easy’ fix to people who we know we benefit from aortic valve replacement surgery before we have all the data.

There are still multiple issues to be addressed with transcutaneous valve therapies – we don’t even know the durability of this technology (how long with they last?)  or the long-term complications..   Also when we compare ourselves to European practices, we need to remember that ‘acceptable thresholds’ may differ significantly.  At what level of risk of stroke are YOU willing to accept?  5 % ?  10% ?  25% ?  And doesn’t that depend on whether you are eligible to have other therapies, and what the risks of those therapies are?

Lastly, it’s important to note that the study in question – which revealed a higher than expected stroke rate was funded by the corporations that manufacture and supply these valves.  We’ve seen before how this can influence the practice of cardiology and cardiology guidelines.

Article re-post below: [my comments in brackets.]

Surgeons caution against

 overenthusiasm for TAVI in light of

PARTNER A stroke data

May 10, 2011            |            Reed Miller

Philadelphia, PA – The neurological injury data from the PARTNER cohort A trial of transcatheter aortic-valve intervention (TAVI) underscore the importance of the collaboration between surgeons and interventionalists when making decisions on how to treat patients in need of a new aortic valve, surgeons here at the American Association for Thoracic Surgery (AATS) 2011 Annual Meeting agreed.

As reported by heartwire, Dr Craig Miller (Stanford University, CA) presented new details on the neurological-event data from PARTNER cohort A, which included high-risk patients eligible for either surgery or TAVI. [‘high risk’ needs to be better defined if the patients were considered acceptable surgical candidates.] 

The data showed that the risk of neurological adverse events (transient ischemic attack [TIA] and stroke) was slightly higher with TAVI than surgery in the “as-treated” patients, especially in the patients who underwent transapical TAVI because their vessels were too small to accommodate a transfemoral implant, usually because they were obstructed with arteriosclerosis. Rates of major stroke, however, were not statistically different between the two groups in the as-treated analysis.  [numbers/ percents – I need hard data..]

Because of the added neurological risk, Miller believes TAVI should not replace surgery for most patients who can withstand surgery. So he is dismayed that it has grown so rapidly in some European countries where TAVI devices are commercially available, even though the durability of these devices has not been proven. “This is not going to be cost-effective, and civilization cannot afford this if they do not last a good amount of time, and a good amount of time would mean something different to a 95-year-old who is inoperable and to somebody under 70 with a very low surgical risk who should have 10- to 20-year life expectancy. So we have to look at valve durability,” he said.  [I wholeheartedly agree. All of Dr. Miller’s concerns are valid.]

“There are many [inoperable patients like] the people in PARTNER cohort B, who gained 1.9 quality-adjusted life-years, and it only cost $55K per QALY to achieve that. So for the inoperable cohort, it is cost-effective and actually provides meaningful rehabilitation, but the jury is out for the younger patients,” he said. “But the cost economics of the not-so-sick operable patients is going to be different; they’re still beaucoup sick and old in PARTNER A, but to take this down to younger, healthier patients is a huge question mark in my mind and in the FDA‘s mind, because we already have the gold standard of low-risk, durable, surgical [aortic-valve replacement],” Miller said.

Surgeon/interventionalist collaboration is critical

Miller thinks one reason that TAVI has become “a runaway train” in Europe is that in some countries there, interventionalists are able to decide to implant a transcatheter valve without consulting a surgeon or, in some cases, even having a surgeon on site. “The German Federal Ministry of Health didn’t have the backbone to stand up and legislate appropriate use, so it’s a free-for-all. But that would be wrong, especially since we don’t have durability data,” Miller said. Miller said he learned that about a quarter of aortic-valve replacements in 2010 in Germany were TAVI procedures, but Dr John Mayer (Children’s Hospital Boston, MA) reported at the meeting that the figure is now around 40%.

A good amount of time would mean something different to a 95-year-old who is inoperable and to somebody under 70 with a very low surgical risk who should have 10- to 20-year life expectancy.

Mayer and Dr Grayson Wheatley III (Arizona Heart Institute, Phoenix) echoed Miller’s concerns about overenthusiasm for TAVI during a staged luncheon debate on whether or not expensive technologies like TAVI ought to be somehow rationed to control healthcare costs. Mayer took the position of defending rationing and Wheatley argued against it, but they both agreed that physicians and their professional societies ought to work to ensure appropriate use of TAVI.

Wheatley said, “We’re probably going to see something along the carotid-stent paradigm, where it’s FDA approved, but [the Centers for Medicare & Medicaid Services] CMS has restricted [coverage] of an FDA-approved device, based on the data and economics, to the highest-risk patients. I see a lot of parallels there.”

“The Medicare national coverage decision process is going to undoubtedly come into play,” Mayer agreed. “That’s one way to control it, and that’s probably the biggest weapon in the arsenal.” Mayer said that the CMS is already discussing a future Medicare coverage policy for TAVI with the Society of Thoracic Surgeons (STS).

“But the other way to control it is to take the combined cardiology/cardiothoracic surgery approach to be careful about how this gets rolled out,” he said. The STS and the American College of Cardiology (ACC) are currently working on a joint position paper that will call for TAVI appropriateness guidelines based on the PARTNER results, Mayer pointed out. That paper will likely be published this summer. “That’s an extremely important step, and I think the government will understand and accept a lot of the recommendations in there.”

Meanwhile, the Society for Cardiac Angiography and Interventions (SCAI) will be contributing to the STS/ACC position paper and is also developing an expert consensus document with representatives from the AATS, STS, and ACC that will outline training and facility standards for performing TAVI. That document will be published prior to the TCT 2011 conference, according to SCAI.

“The difference between how this was rolled out in Europe and how the investigators in the PARTNER trial would like to roll it out in the United States is that a heart team with a surgeon and cardiologists—and not just the interventional cardiologists, but general cardiologists—make the decisions jointly. That is the model that we think should be imposed going forward,” Mayer said. This collaboration will “be a way of us fulfilling our professional responsibility and making sure that this gets rolled out with high quality and will have the side benefit of keeping it from going nuts like it has in Europe.”

While some may be better off undergoing surgery than transfemoral TAVI, there are also some patients whose risk of neurological injury is so high due to arteriosclerotic burden that they are probably not suitable for either surgery or TAVI, Miller said. “The only thing that’s going to change that is more rigorous patient selection and just saying no,” Miller told heartwire. “That might not go over well in the US where everybody demands everything yesterday, [but] since these are patient-disease-related predictors, more rigorous patient selection is the only thing that will reduce the late hazard of neuro events [in patients with very high arteriosclerotic burden].”

What does PARTNER cohort A reveal about the cause of strokes?

STS president and PARTNER investigator Dr Michael Mack (Medical City Dallas Hospital, TX) told heartwire, “There was an initial thought for the past few years that the transapical might be more neuroprotective than the transfemoral because you don’t transverse the aortic arch with the device, and I think this puts to bed that that was not the case. In fact, the stroke rate was higher in the transapical than in transfemoral, but the presentation showed that it was clearly related to the patient substrate.” The one-year stroke rate in the transfemoral-eligible surgery patients was 1.9%, while the one-year stroke rate for the same surgical procedure in transfemoral-ineligible patients was 9.7%, Mack pointed out. “That says they’re different patients [with] a higher atherosclerotic burden.”

[Collaboration will make] sure that [TAVI] gets rolled out with high quality and will have the side benefit of keeping it from going nuts like it has in Europe.

Mack pointed out that the version of the Sapien valve (Edwards Lifesciences) tested in PARTNER was a first-generation device that did not have the nose cone that newer versions will have, “so you basically had this snowplow that could go across the aortic arch and scrape stuff off; smaller delivery devices with nose-cone protection may be expected to be of benefit,” Mack said. However, previous studies with transcranial Doppler show that the majority of the emboli come from the valve during balloon valvuloplasty and deployment of the valve and not from the aortic arch. “[This is] why you don’t see a benefit of the transapical here, because you’re still blowing up that valve [inside the native valve].”

This explanation is consistent with the study’s finding that, in the first few weeks following the procedure, a smaller valve opening area, which is usually a sign of high calcification around the opening, was associated with a higher risk of neurological events in the TAVI patients. Embolic-protection devices, such as Edwards’s Embrella, may catch some of these emboli released during the valve deployment, Mack said, but clinical experience with these devices is very limited so far.

Better devices may stop a lot of the periprocedural events, but about half of the neurological events happened after the periprocedural period. In this period, the most important risk factor—other than undergoing TAVI instead of surgery or being transfemoral ineligible—was a stroke or TIA within the previous six to 12 months. Atrial fibrillation, which was predicted by some to possibly be a risk factor for strokes, was not associated with an increased risk of neurological events in the study. Dual antiplatelet therapy was recommended for all patients in the trial, but the trial could not track how compliant patients were with that therapy.

“We have absolutely no clue if these strokes were device related or not. We don’t know if the device is thrombogenic, or if all that calcium left in the aorta hanging out eventually breaks out, or if it’s a nidus for clot formation and that breaks off. We just don’t have any insight on that,” Mack said.

PARTNER was sponsored by Edwards Lifesciences. Miller has consulting arrangements with Medtronic CardioVascular, Abbott Vascular, and MitraClip. Mack consults for Edwards Lifesciences and Medtronic.

Aortic Stenosis: More patients need surgery


An interesting new article on the use of echocardiography (cardiac ultrasound imaging) to determine the optimal timing of aortic valve replacement is re-posted below.  This article is helpful for several reasons, but first a quick summary of Aortic Stenosis.

The timing of aortic valve replacement surgery for aortic stenosis (here after referred to as AS) has always been a complicated issue.  Not all stenotic valves need to be replaced at the time of diagnosis; in fact, most don’t since AS is usually diagnosed early (from the presence of a new heart sound on physical examination.)

Patients may not need surgery for ten or twenty years after AS is initially detected, and performing surgery at the RIGHT time is important.  Performing surgery too early has almost as many drawbacks as performing surgery too late.

Ideally, surgery is performed before the patient becomes symptomatic (fainting/ near fainting, chest pain or the development of heart failure) AND before the development of heart damage from AS.

Article re-post:  [my comments in bracketsI have also italicized certain portions for emphasis.

Echo predicts mortality in untreated

 Aortic stenosis with normal LV

function

Article authored by Marlene Busko, Heartwire.com  (June 17th, 2011)

Montreal, QC – Researchers have identified four  echo markers that predicted mortality in elderly patients with severe aortic  stenosis but preserved LV function who did not undergo surgical valve  replacement [1].
Dr Eddy Barasch (St Francis Hospital, Roslyn, NY) presented the  study here at the American Society of Echocardiography (ASE) 2011 Scientific  Sessions.

The four echocardiographic markers that predicted poor  survival were greater left ventricle (LV) concentric remodeling, lower stroke  volume, elevated LV filling pressures, and mildly elevated pulmonary artery pressure.

“Our findings may not be generalizable, but they suggest that in [elderly, symptomatic patients with untreated aortic stenosis] with normal LV function, no other valve disease, and normal sinus rhythm, these  echocardiographic parameters may be useful for risk stratification,”
Barasch told heartwire. Being able to predict mortality with surgery vs medical therapy in patients such as these—who are typical of patients seen in clinical practice—will become even more important when  transcatheter aortic-valve implantation (TAVI) becomes available, he added.

The data suggest that “not operating on symptomatic  patients like this—with these markers—is really a death sentence,” said Dr Malissa Wood (Massachusetts General Hospital Heart Center, Boston), when asked to comment on the study.”When you are managing patients who may in  fact be good candidates for surgery, looking at their echo and figuring out if
they have these risk factors can help determine the patients’ overall risk of
mortality with surgery vs medical therapy,” she added.  [I completely agree with Dr. Woods, which is why we need to be frank in our discussions of the real risks of surgery and the risks of NOT having surgery.]

Surgery seen as “too risky”

The prevalence of aortic stenosis increases with age, and it is estimated that among 80-year-olds, as many as one in four have aortic stenosis, and about 3% to 5% have severe aortic stenosis, Barasch explained.   However, a significant proportion of patients with aortic stenosis—30% to  40%—are denied surgery for various reasons, he noted. The patients may have
multiple comorbidities, be too old and frail, or may not want to have surgery.

In some cases, a primary-care physician may not refer a patient for surgery due to perceptions that the procedure is too risky, while in others, a surgeon may decide that a referred patient is not a good candidate for surgery, Wood added.
[The wording here is deceptive – if a patient decides not to have surgery – they weren’t ‘denied surgery’.  People have the right to decide for themselves – as long as we ensure that we explain everything to them in terms they can understand.  This phrasing is concerning now that many cardiologists are performing experimental transcutaneous valve procedures – sounds like cardiologists are opening the door to doing this procedure in patients that may not otherwise be candidates under “the patient was denied surgery/ patient refused surgery” model which we’ve seen many times before with stent patients.]

[The other issue that we will talk about in a future post is the “primary care provider (PCPs)” not  referring patients that he/she doesn’t think are good candidates.  Frankly, most PCP  and cardiologists, for that matter, are not qualified to make that determination.  As you will read further into the article and see – the outcomes of untreated AS are quite grim, so the
decision on whether or not to refer a patient for evaluation, is not one to be taken likely.]

“On the other hand, if you don’t treat these patients surgically, mortality is increased twofold,” said Barasch.

Although most elderly patients with severe aortic stenosis have preserved LV function, few studies have examined how risk factors  affect survival in this patient subset. To identify echo variables associated  with mortality in these patients, the team reviewed the charts of 443
consecutive patients with severe aortic stenosis and preserved LV ejection fraction who had echo Doppler in their center from 2003 to 2010.

After patients who underwent surgical aortic-valve replacement were excluded, the study population comprised 274 patients with a mean age of 79.5 years (51% men). [this is quite a large subset of patients that didn’t/ couldn’t/ didn’t want surgery.  I’d like to know why, and who decided (other than the patients themselves). We successfully do aortic valve replacement in many patients over 80 (age itself should NEVER be a factor – as discussed in numerous previous posts.]

All but two patients had symptoms of heart failure (45%), angina (33%), syncope (5%), or multiple or other symptoms (17%).  All patients had normal sinus rhythm, and their mean LVEF was 64.5%+9.4%.

After a mean follow-up of 3.2+2.7 years, 50.5% of the patients had died.

The patients who survived were younger, had a higher body-mass index (BMI), and were less likely to have hypertension, renal insufficiency, diabetes, or heart failure, and more likely to have CAD.

Of the multiple echo-Doppler variables that were examined, only four parameters—LV concentric remodeling (increased LV wall thickness), lower stroke volume, elevated LV filling pressures, and mildly increased pulmonary artery pressure—were moderately associated with mortality,  after researchers adjusted for age, gender, and BMI.

No surgery also ups risk

“The biggest take-away message is that we are still grossly undertreating symptomatic aortic stenosis, and many patients who would benefit from surgery are not getting it,” Wood summarized.  The study helps identify the magnitude of the risk of not having surgery, among these elderly patients.  [Actually, we’ve known these statistics for at least twenty years – I had to memorize them for student rounds when I was graduate school, as standard fare for grilling by the cardiac surgeon.]
“It is a strong study—useful for risk/benefit analysis,” she concluded.

Unfortunately, much of this article seems to state that the biggest obstacle to patient care, safety and welfare seems to be the referring physicians themselves.  In my opinion, ALL patients with AS should be referred to a cardiac surgeon (not because I work for one) but because ONLY the surgeon and the patient can truly decide whether its’ time for surgery/ and if the benefits outweigh the risks.

So, if you have Aortic stenosis, symptoms or not – get your more recent echocardiogram, a list of all your medications, and as many medical records as you can get – and schedule an appointment with a cardiac surgeon for a second opinion.

I’ll be posting some additional articles and references for interested readers soon.

 

Aortic Stenosis as Heinz 57


“Aortic Stenosis as Heinz 57”

I apologize, but the best analogy I can use – is a squeeze ketchup bottle.

okay, it's not heinz.. but you get the picture..

In normal valve functioning, the three valve leaflets open and close fully to permit and control the flood of blood from the left ventricle to the aorta, where it is then circulated throughout the body.

normal valve diameter

During diastole (the filling phase) the leaflets are shut to prevent blood from leaking backwards from the aorta into the heart.  (When leaflets don’t close properly this is called aortic regurgitation.)

During systole, the ventricle contracts like a big fist,  squeezing the ketchup bottle to shoot blood out of the heart into the aorta.  (The force of this is measured in millimeters of mercury, and is the top number on your blood pressure cuff).  When the valve is working normally, it opens fully and the blood is ejected out to the aorta, and the whole cycle begins again.

In Aortic Stenosis – the valve leaflets have become fused together, either from age or disease.
(Some people are born with only two valve leaflets and this means that they are more likely to develop aortic stenosis as they age.)  As aortic stenosis progresses, the opening for blood to pass thru becomes smaller and smaller since the leaflets can not longer open fully,  In many people – at the time of surgery – this opening is about the size of the pinhole in the ketchup bottle that squirts ketchup.      (The normal sized opening is 2 to 3 centimeters).

average valve opening in severe aortic stenosis

Now, think about how hard a person has to squeeze that ketchup bottle to get some ketchup for hamburgers, fries (and all the other foods I usually scold about in other posts).
In the heart – this pressure is magnified (and can be measured in the cath lab during cardiac catheterization).

As this pressure gets higher and higher to compensate for the narrowed opening, the delicate structures of the heart become damaged, with the heart muscle becoming thicker and less flexible (just like any other muscle with exercise.)  Except unlike biceps, a big thick heart muscle is not a good thing, and can lead to heart failure, arrhythmias and sudden cardiac death.

Eventually, as the heart pushes against the increased pressure, over and over (at least sixty times per minute) the heart gets tired from working so hard.  As the heart fatigues, it is unable to keep up with demand and patients will begin to develop symptoms.

These symptoms include:

Syncope/ near syncope (fainting or near fainting) as not enough blood is pushed into central circulation and to the brain.

Chest pain – because not enough blood is pushed out to the coronary arteries during diastole.  (In a person with aortic stenosis, nitroglycerin can cause problems – as it lowers blood pressure  (and force of contraction even further in someone who needs the extra force.)

Heart failure – the weakened and thickened heart can no
longer keep up and blood begins to back up in the left ventricle.

What these symptoms predict:

Once these symptoms develop, doctors can readily estimate the approximate longevity for patients who do not subsequently have surgery.

From the natural history of aortic stenosis (from before we had surgery to treat it) we know that 50% of people with Syncope will die within 5 years.

Fifty percent of people with chest pain die within three years.

And ultimately, fifty percent of people with heart failure die within two years.

These numbers are important, and I want you to remember them for our subsequent discussions on aortic valve replacement because they need to be factored into a patient’s decision whether or not to pursue surgery.