Aortic Valve Replacement & the elderly


I just read an interesting article in the Annals of Thoracic Surgery.

Unfortunately, the full-text article is not available for free – but I did find a nice article abstract (which I’ve posted below.)  It confirms some of the previous discussions we’ve had here at Cartagena Surgery on the role of surgery in Aortic Stenosis, even in ‘elderly’ patients.  [I put elderly in quotes since the definition can be fairly elastic depending on who is doing the judging.]

The article below is from Medscape.com

Aortic valve replacement in the elderly: the real life.

Ann Thorac Surg. 2012; 93(1):70-8 (ISSN: 1552-6259)

Langanay T; Flécher E; Fouquet O; Ruggieri VG; Tour Bde L; Félix C; Lelong B; Verhoye JP; Corbineau H; Leguerrier A Department of Cardiovascular and Thoracic Surgery, University Hospital, Rennes, France.

BACKGROUND: Aortic stenosis is of concern in the elderly. Although aortic valve replacement provides good long-term survival with functional improvement, many elderly patients are still not referred for surgery because of their age. Percutaneous aortic valve implantation offers an alternative to open-heart surgery. Concerns about the management of aortic valve stenosis in the elderly will be reviewed.

METHODS: We retrospectively analyzed 1,193 consecutive aortic valve replacements, performed in octogenarians since January 2000. A total of 657 patients (55%) had at least one associated comorbidity (eg, respiratory failure) and 381 (32%) associated coronary lesions. Valve replacement was the only procedure in 883 patients (74%), and was associated with coronary revascularization in 262 cases, or with another cardiac procedure in 48 patients.

RESULTS: Overall operative mortality was 6.9% (83 of 1,193 patients); 5.5% for single replacement and 11.5% if associated with coronary artery bypass surgery. Univariate and multivariate analyses identified 11 operative risk factors related to general status, cardiologic condition, and the procedure itself: older age (p< 0.015); respiratory failure (p <0.03); aortic regurgitation (p <0.001); emergency surgery (p <0.0029); New York Heart Association class IV (p < 0.0007); right heart failure (p < 0.03); atrial fibrillation (p < 0.04); impaired ejection fraction (p < 0.001); coronary disease (p < 0.01); redo surgery (p < 0.02); associated coronary revascularization (p < 0.008).

CONCLUSIONS: Today, valve replacement has acceptable low hospital mortality, even in the elderly. Thus, older patients should not be denied surgery due to their advanced age alone. Conventional surgery remains the gold standard treatment for aortic stenosis; the decision should be made on an individual basis. If several risk factors suggest very high-risk surgery, then percutaneous valve implantation should be considered instead.

In more disturbing news:

As predicted, the unproven ‘easy option’ of TAVI is now being pursued by more low-risk patients.  These lower risk patients are people who should have been encouraged to undertake the more durable, safe and proven surgical therapy [Aortic Valve Replacement.]  I guess this just shows how quickly those new recommendations [for patient protection and safety] were thrown out the window.

In this article (posted below) by Kurt Ullman at Medpage Today – German researchers discuss their preliminary findings and discuss the use in low risk patients.

The bar for transcatheter aortic valve implantation (TAVI) is dropping as more lower-risk patients are undergoing the procedure and their outcomes are favorable, a single-center study from Germany found. [Unfortunately – as we’ve seen so many times in the past, and as I am finding out while preparing this presentation on the Syntax trial – studies such as this can be quite deceiving – and LONG term data is needed. – Cartagena Surgery].

When stratified by quartiles based on enrollment date, Q1 patients had higher logistic EuroSCOREs, higher Society of Thoracic Surgeons (STS) scores, and higher median N-terminal pro-B-type natriuretic peptide levels compared with those enrolled later in Q4, noted Nicolo Piazza, MD, PhD, and colleagues from the German Heart Center in Munich.

Although there were significant decreases in 30-day and six-month mortality from Q1 to Q4 in the crude analysis, after adjustments for baseline characteristics, the significant differences disappeared (HR 0.29 for 30-day mortality and HR 0.67 for six-month mortality), according to the study published online in the Journal of the American College of Cardiology.

“These results suggest that underlying comorbidities play an important role in acute and intermediate-term survival after TAVI,” the researchers wrote.

The researchers noted anecdotal information suggesting a shift toward using TAVI in patients who are less sick than those enrolled in premarket trials. Additionally, the next wave of trials involving the CoreValve (Medtronic) and the Sapien XT (Edwards Lifesciences) devices will involve intermediate to high surgical risk patients, providing “yet another indication that TAVI is being directed at the treatment of lower and lower surgical risk patients,” Piazza and colleagues wrote.  [There are significant ethical considerations here which seem to be ignored – similar to criticisms of the Syntax trial – Cartagena Surgery.]

A single-center French study of low-risk TAVI patients found the procedure to be safe in this population. The study was presented at the European Society of Cardiology meeting in Paris.

The impact on this shift in patient selection was uncertain, they said, prompting a retrospective review of 420 patients who underwent TAVI at their institution from June 2007 to June 2010.

The consensus that a patient was suitable for TAVI was derived from a team that comprised cardiologists, cardiac surgeons, and anesthesiologists. This team approach is exemplified by the recent announcement that the American College of Cardiology and the Society of Thoracic Surgeons will jointly sponsor a TAVI registry to monitor the safety and efficacy of the procedure as it rolls out in the U.S.

Patients received either the CoreValve or Sapien device, the latter of which was just approved for use in the U.S. based on the PARTNER trial. PARTNER found that TAVI was as good as surgery in high-risk patients with severe aortic stenosis. [‘as good as’ – ah.. another ‘non-inferiority’ study….. view with skepticism folks..]

Researchers divided patients into four quartiles of 105 patients each. Those in Q1 were seen earlier in the study time frame than those in Q4.

Compared with Q4, Q1 patients had higher EuroSCOREs (25.4% versus 17.8%, P<0.001), STS scores (7.1% versus 4.8%, P<0.001), and NT-proBNP levels (3,495 versus 1,730 ng/dL, P<0.046).

There were significantly less transfemoral access approaches from Q1 to Q4, with a concomitant rise in transapical approaches. There also were significantly less intubations moving from Q1 to Q4, and the use of contrast significantly decreased over time.

Researchers noted that transfemoral complications decreased by 17% from Q1 to Q4 (P=0.008), but found no significant differences in the rate of stroke or transient ischemic attack or the need for a permanent pacemaker.

However, there was a shift in the later quartiles toward the treatment of younger patients with fewer comorbidities and lower surgical risk scores, Piazza and colleagues wrote.

Univariable analysis for 30-day mortality showed it was associated with age, STS score, atrial fibrillation, previous heart surgery, and previous stroke (P<0.10).

The factors associated with six-month mortality were age, logistic EuroSCORE, STS score, left ventricular ejection fraction, atrial fibrillation, previous cardiac surgery, chronic obstructive pulmonary disease, and N-terminal pro-B type natriuretic peptide (P<0.10).

Because only baseline characteristics were included, the authors noted the possibility that procedure-, operator-, or device-related factors might influence both 30-day and six-month mortality. The study is also limited by potential unmeasured confounding.

The investigators cautioned that little is known of the long-term durability of these devices should they be routinely implanted in younger patients with a longer expected life span.  [especially since the lifespan of the patients these valves were designed for was six months to one year..]

Piazza is a consultant and proctor for Medtronic and CardiAQ. Other authors revealed consultant status with Medtronic and Edwards Lifesciences, or instuctors for Medtronic

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Peri-operative mortality with/after TAVI for aortic stenosis


More on TAVI: A newly published analysis of the existing/ reported data for peri-operative mortality after transcatheter aortic valve implantation looking at 12 previous studies was recently (June) published in the journal of Interventional Cardiology.  (While the study looks at the causes of death – we here at Cartagena Surgery – are going to talk about the rate of death in this study.)

Article information:

Causes of Peri-Operative Mortality After Transcatheter Aortic Valve Implantation: A Pooled Analysis of 12 Studies and 1,223 PatientsThe Journal of Invasive Cardiology 2011;23(5):180-184.

Raul Moreno, MD; Luis Calvo, MD; Pablo Salinas, MD; David Dobarro, MD; Jimenez Valero Santiago, MD; Angel Sanchez-Recalde, MD; Guillermo Galeote, MD; Luis Riera, MD; Isidro Moreno-Gomez, MD; Jose Mesa, MD; Ignacio Plaza, MD; Jose Lopez-Sendon, MD

Abstract re-posted below.

Background. In order to improve technique and to prevent serious procedural complications during transcatheter aortic valve implantation (TAVI), it is crucial to identify the causes of death of patients undergoing this procedure.
Objective. The objective of this study was to identify the causes of death during the procedure and at 1 month in patients with severe aortic stenosis undergoing TAVI.

Methods. 12 published studies with information about the causes of death in patients undergoing TAVI were selected. Overall, 1,223 patients were included in these studies, and 249 deaths were reported (119 at 1 month and 130 at > 1 month post-procedure).

Mortality during the procedure and at 1 month was 2.3% and 9.7%, respectively. The proportion of cardiac deaths was higher at < 1 month in comparison with > 1 month (56% versus 34%, respectively; p = 0.001). At 1 month, the most frequent causes of death were cardiac failure/multi-organ failure (24%), sudden death/cardiac arrest (17%), vascular and bleeding complications (17%), stroke (11%), sepsis (11%), and cardiac tamponade (10%). During the procedure, the most frequent causes of death were cardiac tamponade (39%), cardiac failure (21%), cardiac arrest (18%), and vascular and/or bleeding complications (18%).

In patients treated with the CoreValve system (Medtronic, Minneapolis, Minnesota) versus those treated with Edwards valves (Cribier-Edwards, Edwards-SAPIEN or SAPIEN XT valve, Edward Lifesciences, Irvine, California), deaths at 1 month due to vascular and bleeding complications were less frequent (3% versus 22%, respectively; p = 0.019), but those due to cardiac tamponade (26% versus 6%, respectively; p = 0.019), and because of aortic regurgitation (10% versus 0%, respectively; p = 0.03) were more frequent.

Conclusion. In this pooled analysis, mortality at 1 month after TAVI was 9.7%. The causes of death were widely variable, and of both cardiac and non-cardiac origin. There were some important differences between both devices in the cause of mortality.

How does this compare with conventional aortic valve replacement surgery (AVR)?

In cardiac surgery – surgeons use database calculators.  The most popular one is called the STS risk calculator to determine or estimate the surgical risk for specific patients.  This calculator is based on thousands and thousands of patients over decades of research to give approximate surgical risk of morbidity (post-operative complications) and mortality by looking at the planned procedure as well as patient risk factors (age, poor heart function, co-morbidities).  Other calculators include a European calculator called EUROscore, and a score used  by the VA (veteran’s hospitals.)

Well, how accurate are these calculators?

Interestingly enough – at the same time as the TAVI article, an article (Basreon et. al) discussing and comparing each of these calculators to actual results was published in the June 23 issue of the Annals of Thoracic Surgery.  (I’ve re-posted the abstract below.)

In their research – Basreon et. al. found the overall peri-operative mortality for aortic valve replacement surgery to be 5.9%  which is well under the 9.7% reported in the article by Moreno, et. al (re-posted above) for TAVI.

While the argument can be made that the higher than expected peri-operative mortality in the TAVI group may be secondary to other factors (patient condition at time of TAVI) without more information on patient demographics – it is hard to know.

I, for one, would like to know the average ages of patients in both groups – was the TAVI group made up of non-surgical fragile, 95 year-olds?  What specific factors raised their EUROscores? Was it overall heart function, or was it a specific co-morbidity?

It’s difficult to know since it’s a composite of other research data from multiple studies (and since TAVI is widely used in Europe, accounting for as many as 40% of all aortic procedures in Germany, for example) – this data may also reflect many of these patients (who are not frail elderly, for example.)

Reading through the Moreno study – there is little discussion of the actual patient population, except for one small paragraph (re-posted below). Both of these limitations are probably due to the nature of the study – where investigators were pooling the results of several different studies – which is a good strategy to get a wide overview.  However, this can make it impossible to go back and look at questions like ours, particularly if the investigators on the original, smaller studies didn’t record / report this information.

[my comments in brackets/ italics].  I have placed data within the article in bold or italics. 

“In this study, pooling the results of 12 series, mortality at 1 month in patients treated with TAVI was 9.7%, and mortality during the procedure was 2.3%. These data compare favorably with the predicted surgical mortality, since EuroSCOREs ranged from 12–28%.  [this is the risk calculator that Basreon et. al found that grossly overestimated risk in the study re-posted below.]

In the randomized PARTNER trial, a significant reduction (~20% absolute risk reduction) in the 1-year mortality was obtained for patients with severe aortic stenosis and considered not suitable for surgery due to a very high surgical risk when treated with TAVI in comparison with medical treatment. [as you know from previous discussions – medical treatment is exceedingly ineffective for this condition.  It would be more helpful if authors had better defined their ‘very high’ risk patient group since multiple studies show that cardiologists, etc. overestimate patient’s surgical risk.] 

Importantly, mortality significantly reduced through the years, from 2004 to 2010, probably reflecting not only the learning curve and the technical improvements, but also a better patient selection process. [meaning patients that are ineligible for surgery may also be ineligible for TAVI in some cases.]   This reduction in mortality over time has also been observed in single-center experiences.

Although not statistically significant, mortality at 30 days was higher in patients treated by transapical approach in comparison with transfemoral approach. Probably, the worse clinical profile of patients undergoing transapical TAVI justifies, at least in part, these findings.[7,12]

Ann Thorac Surg. 2011 Jun 23. [Epub ahead of print] Comparison of Risk Scores to Estimate Perioperative Mortality in Aortic Valve Replacement Surgery.

Source

Division of Cardiology, Veterans Administration Medical Center and University of Minnesota, Minneapolis, Minnesota.

Abstract  (bolding/ italics from original article)

BACKGROUND:

Transaortic valve implantation has recently been introduced as an alternative to aortic valve replacement (AVR) for high-risk patients with aortic stenosis. However, accurate assessment of surgical risk is critical for appropriate patient selection. We compared the accuracy of The Society of Thoracic Surgeons (STS) risk score, the European System for Cardiac Risk Evaluation (EuroSCORE), and the Veterans Administration (VA) risk score in predicting perioperative mortality after AVR.

METHODS:

We included 537 consecutive patients who underwent AVR for severe aortic stenosis at the Minneapolis VA Medical Center between 1997 and 2008. Observed and predicted perioperative (30-day) mortality rates were compared. Hosmer-Lemeshow goodness-of-fit test and receiver operating characteristic curves were performed to assess the performance of the scores.

RESULTS:

Perioperative mortality rate was 5.9% (n = 32). Predicted mortality rates for the EuroSCORE, STS score, and VA score were 15.6%, 3.6%, and 6.7%, respectively (p = 0.001). The EuroSCORE overestimated mortality in all patients, most notably among those with ejection fraction less than 35% (49% predicted versus 9% observed). The EuroSCORE had poor calibration (goodness-of-fit test p < 0.008), whereas the STS and the VA scores were well calibrated. However, all three scores displayed good discrimination characteristics per the areas under the receiver operating characteristic curves: STS score 0.73 (95% confidence interval: 0.69 to 0.77); VA score 0.66 (95% confidence interval: 0.62 to 0.70); and EuroSCORE 0.68 (95% confidence interval: 0.64 to 0.72; p > 0.05).

CONCLUSIONS:

The EuroSCORE substantially overestimates perioperative mortality risk in AVR, particularly in patients with low ejection fraction. These data have implications when deciding the appropriate intervention (transaortic valve implantation versus AVR) for high-risk aortic stenosis patients.

In general – the majority of the literature cites peri-operative mortality for AVR at 2.0 – 5.0% (but this is an average of ALL patients, making the calculators our best estimate of predicted risk.)

So what does this mean?

Clearly, when the data from Moreno et. al shows a thirty-day (peri-operative) mortality of almost 1 in 10 patients – it’s a signal we need to proceed with caution, and continue to follow the research.

1.  Since the authors report many of these patients at very high surgical risk (presumably due to cardiac status as well as co-morbidities) and 2. we know that in most people aortic stenosis progresses slowly  – it stands to reason that we need to consider intervening earlier in the course of the disease.  (Before the heart is significantly weakened).

For people with Aortic Stenosis – I’d want to get second/ third opinions from a cardiac surgeon before proceeding with any catheter based valve procedures.  I’d bring all of my information, and studies (echocardiogram results, lab results, medication lists) to have a serious talk to the surgeon about my surgical risk – (and ask him to calculate and show my risk based on the STS calculator).  I certainly wouldn’t let anyone make any decisions about my health/ care based on my age alone.  [we’ve talked about a ‘good 80’ versus a ‘bad 80’ or even a ‘bad 50’ before.]

Then, I would weigh all of the information – and do my best to make an informed decision.

Other posts about Aortic Stenosis/ TAVI/ AVR:

1. TAVI overview

2. TAVI: a stent scenario

3. TAVI recommendations

4. Aortic Stenosis and TAVI

5. Aortic Stenosis as Heinz 57

6. Aortic stenosis and surgery

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.

Book Advertisement


Created a new advertisement for the book. Now, obviously for reasons of patient privacy, HIPAA and all of that – we’ve changed the names, and pictures of the people involved. (I did obtain permission from the patient to use surgery photos in print, video and other media).

This is the first in a series of ads for the book, so let me know what you think.