ACCEL: American College of Cardiology of Extended Learning
ACCEL interviews and topical summaries of cardiology’s most interesting research areas

5-Year Results from PARTNER and TAVR: Next Gen

Like 1-, 2-, and 3-year data, the final 5-year follow-up of the Placement of Aortic Transcatheter Valves, or PARTNER study, continues to demonstrate that the Sapien transcatheter heart valve is a feasible option for patients with severe aortic stenosis (AS) deemed to be at high risk for open-heart surgery. Indeed, the procedures were equivalent with no significant difference in all-cause and cardiovascular mortality, stroke, New York Heart Association class, rehospitalization, or valve hemodynamics. Moreover, during the follow-up period, there were no signs of structural valve deterioration or loss of valve function with transcatheter aortic valve replacement (TAVR).

“The negative part of this trial is the ongoing issue of paravalvular leak with TAVR,” said Michael Mack, MD, FACC, Baylor Scott and White Health, Dallas, TX. Moderate or severe leaking was 14% with TAVR vs. 2.1% with surgery. Mortality was 9% higher in patients with paravalvular leak, and even mild leaking was associated with increased mortality at 5 years compared with patients who had none or only a trace amount.

Since trial enrollment started, much has been learned about the predictors and causes of paravalvular leak and methods for proper sizing of the valve prosthesis relative to the aortic annulus. Use of three-dimensional (3D) multislice computed tomography (CT) scan reconstruction and 3D transesophageal echocardiography, which were not used in PARTNER, has refined valve sizing. Additionally, the availability of a wider range of valve sizes has helped to address this problem.

“At 5-year follow-up,” Dr. Mack said, “PARTNER 1 supports the fact that TAVR is an alternative to surgery in high-risk patients. Both approaches having similar mortality and other major clinical outcomes as well as similar functional outcomes while improvements in valve function were maintained in both groups.” Overall, he added, “Any time you have two treatments and one’s more invasive than the other, the less invasive treatment always wins, so the fact that TAVR and surgery were a tie in PARTNER 1 means TAVR wins.”

Jeffrey Popma, MD, FACC, Director of Interventional Cardiology Clinical Services, Beth Israel Deaconess Medical Center and professor of medicine, Harvard Medical School, Boston, MA, said, “I think it’s just spectacular that we were able to follow these patients out to 5 years and that a third of them are alive. And they lived 3.5 more years after TAVR (median: 44.5 months). It’s just incredible.”

TAVR Next Gen

In their paper, published simultaneously in The Lancet, Mack and colleagues noted that clinical outcomes and valve performance in this 5-year follow-up report might not reflect that of subsequent generations of balloon-expandable transcatheter valves. Indeed, the Sapien device used in the trial is no longer being implanted, replaced by a second-generation device (Sapien XT; Edwards Lifesciences, Irvine, CA).

At ACC.15, investigators presented pivotal trial results for the newer Sapien 3 heart valve. They reported lower death, stroke, and paravalvular leak rates than earlier-generation devices among patients at high risk for surgery (TABLE). Susheel Kodali, MD, FACC, Columbia University Medical Center/New York-Presbyterian Hospital, New York City, NY, said, “We now have intermediate-risk data where we’re getting to a 30-day 1% mortality risk and a 1% stroke risk. How much better data do we need?”

Dr. Kodali added that for several years now, the concept has been to consider TAVR when surgery is not a good option, “but based on this data with a 1% stroke risk and 1% mortality, maybe the conversation shouldn’t be ‘TAVR when surgery’s not a good option’ but rather TAVR is the preferred option—at least in 80-year olds.” (Average age at baseline in this trial was 82.6 years.)

Dr. Mack and his coauthors also noted that the patients selected for treatment in PARTNER, which started in 2007, are also representative of clinical practice at that time; clinicians have since refined patient selection, at least partly on the basis of early outcomes from PARTNER. Thus, in addition to the advances in the device itself, operator expertise and experience, as well as more rigorous patient selection for TAVR, may all contribute to the outcomes now being reported.

Overall, Dr. Mack said to expect to see more high-risk patients with severe AS undergoing TAVR. “The results are virtually identical,” he said, for TAVR versus surgical aortic valve replacement (SAVR). Moreover, he expects to see some indication creep down to more moderate-risk patients. They may be officially at intermediate risk based on their Society of Thoracic Surgeons (STS) score, but if patients have additional factors that could increase their risk, Dr. Mack thinks heart teams will be recommending more patients for TAVR rather than surgery.

References

  1. Mack MJ, Leon MB, Smith CR, et al. Lancet. 2015;385:2477-84.

AUC for Peripheral Vascular Interventions?

Peripheral artery disease (PAD)—atherosclerosis of the lower extremity—is common, affecting 14.5% of the U.S. population over the age of 70. There are guidelines for managing these patients1; should there also be appropriate use criteria (AUC)?

There already are AUC for peripheral vascular ultrasound and physiological testing.2,3 However, there may be a need for something more, if you consider just the options for treating occlusive disease of the superficial femoral artery, some of which include percutaneous transluminal angioplasty, a conventional nitinol stent or a vascular mimetic implant, DES, drug-coated balloons, a stent graft, atherectomy alone (orbital vs. directional vs. aspiration vs. laser), atherectomy plus stenting, or drug-coated balloon with or without atherectomy/with or without stenting.

The growth of endovascular procedures is getting noticed: CMS data show that there are now nearly 360,000 peripheral artery endovascular revascularizations (2013 numbers), which is an increase of 18% since 2005. For peripheral vein revascularization, it’s at 325,000 (up 73%) and for vein ablation (for varicose veins) about 172,000 were done in 2013, an increase of 586%. The increase in peripheral interventions seems to be working: major lower extremity amputation is down 30% over the same time period; lower extremity bypass is down 47%.

There are some concerns relating to this striking growth. Given that some of these procedures for opening peripheral arteries can be done in the doctor’s office, medical experts are questioning the necessity for some of these treatments.

This led The New York Times (Jan. 29, 2015) to note, “Some of the nation’s most highly reimbursed cardiologists are making millions of dollars from Medicare for performing these (peripheral) procedures as payments for relieving blockages in the heart have fallen.”

Is it time for AUC for peripheral vascular interventions (PVI)? Sahil A. Parikh, MD, FACC, Director of the Center for Research and Innovation at University Hospitals Case Medical Center, Cleveland, OH. At ACC.15, he noted that guidelines are valuable but fall short and permit excessive practice variation in the absence of head to head trials.

The Appropriateness of AUC

In a pair of ACC In Touch blog posts,4,5 Michael Wolk, MD, MACC, an ACC Past President, and Joe Allen, MD, Director, Translating Research into Practice at the ACC, provided insights into the “why” of AUC:

  • To ensure the right procedure is performed on the right patient at the right time for the right reasons, to achieve the best possible outcome;
  • To facilitate work with policymakers, payers, and other medical societies to ensure appropriate care;
  • To limit wide variations in care delivery and reduce unnecessary health care costs;
  • To inform (not dictate) care for individual patients; and
  • To engage patients/practices in appropriate use discussions, as a mirror to understand patient case mix over time, and benchmark patient populations against others.

At ACC.15, Dr. Parikh concluded that “the era in which our field can eschew integration of guidelines with AUC seems to have past.” Quality, he said, centers upon the minimization of variability. AUC can be developed with balanced and fair interpretation of the data leaving enough “wiggle room,” as he called it, to permit clinical judgment to prevail—yet, the devil is in the details.

He said, “Lest we regulate ourselves, others will regulate us without benefit of our input to the detriment of our patients.”

An Opposing View

Herbert D. Aronow, MD, St. Joseph Mercy Health System, Ann Arbor, MI, took the opposing position, arguing in his presentation title that AUC for PVD would “create unintended consequences and hamper our ability to do what we think is best.”

One concern he shared relates to patient preference. According to ACC’s AUC Task Force, while it’s not factored into formal appropriateness definitions, patient preference is to be incorporated into decision-making.6 Patients may have different risk tolerances based upon how current health status is valued and no information on patient preference is routinely captured by registries. Thus, Dr. Aronow asked, “How can we rate appropriateness for treatment of PAD without integrating information on patient preference into these decisions,” that is, without shared decision-making?

AUCs purportedly aim to evaluate under- and over-use of diagnostic and therapeutic procedures. AUCs will not be routinely applied to patients/cohorts in whom PVIs have not been considered or performed; therefore, PVI AUC will not address PVI underuse. Given the widespread under-diagnosis and under-treatment of PAD, Dr. Aronow said it remains possible that PVI is withheld when ‘appropriate’ more often that offered when rarely appropriate.

This has been an issue with revascularization in patients with stable ischemic heart disease.7 Using the AUC, investigators identified “substantial underutilization and overutilization of coronary revascularization in contemporary clinical practice.” Underutilization of coronary revascularization, they found, was associated with significantly increased risks of adverse outcomes in patients with appropriate indications.

Another issue: Dr. Aronow noted that data elements and respective definitions will require harmonization across multiple national/regional quality improvement registries. Hospitals will need to provide greater resources (qualified/trained, motivated personnel; sufficient full-time equivalents) in this era of multiple simultaneous registry efforts but without imminent financial repercussions for not doing so.

Another important issue was raised in a 2014 paper in JACC,8 pointing to the disconnect between the guidelines, the appropriate use criteria, and reimbursement coverage decisions relating to implantable cardioverter-defibrillators. Calling it the ultimate dilemma, the authors noted that some AUC scenarios deemed ‘appropriate’ or ‘may be appropriate’ were discordant with clinical requirements of payers, including Medicare, which developed a series of National Coverage Determinations (NCDs) to adjudicate what medical therapies are appropriate for reimbursement. In some cases, the authors pointed out, there was a disconnect between the NCDs and the AUC.

As Dr. Aronow noted, by oath, physicians are sworn to ‘do the right thing’ for patients. Doing the right thing, if not covered, could lead to civil or criminal penalties. What will protect the PVI AUC from the same issues?

In brief, he concluded, PVI AUC will undermine the ability to appropriately treat patients if:

  • AUC efforts are not revised to incorporate patient preference;
  • Clinical scenarios don’t map to real-world data;
  • Data elements/definitions are not harmonized across registries;
  • Health systems don’t allocate appropriate resources to AUC efforts; and
  • AUC is misused to determine individual case reimbursement.

References

  1. Anderson JL, Halperin JL, Albert N, et al. J Am Coll Cardiol. 2013;61:1555-70.
  2. Mohler ER, III, Gornik HL, Gerhard-Herman M, et al.
  3. J Am Coll Cardiol. 2012;60:242-76.
  4. Gornik HL, Gerhard-Herman MD, Misra S, et al.
  5. J Am Coll Cardiol. 2013;62:649-65.
  6. Wolk M. ACC In Touch Blog. May 16, 2012.
  7. Allen J. ACC In Touch Blog. September 5, 2012.
  8. Hendel RC, Patel MR, Allen JM, et al. J Am Coll Cardiol. 2013;61:1305-17.
  9. Ko DT, Guo H, Wijeysundera HC, et al. J Am Coll Cardiol. 2012;60:1876-84.
  10. Fogel RI, Epstein AE, Mark Estes NA, III, et al.
  11. J Am Coll Cardiol. 2014;63:12-4.

2014 AHA/ACC Valvular Heart Disease Guidelines: The Impact on Clinical Practice

In 2014, new guidelines were published for managing patients with valvular heart disease (VHD). Why was it time for new guidelines? Rick Nishimura, MD, MACC, writing committee co-chair, offered several reasons:

  • The new document has more data on natural history of valve disease;
  • Since previous versions, better imaging and quantification are possible; and
  • Given better outcomes from interventions and ‘less invasive’ interventions, which contribute to a lower threshold for their use today, treatment can be extended to sicker patients.

As for specifics, one of the most significant additions is the new classification of VHD stages that consider the degree of valve narrowing or leakage, the presence of symptoms, the response of the left and/or right ventricle to the valve lesion, and any change in heart rhythm.

The guideline also provides a proposed risk assessment tool that should be applied to all patients considered for intervention. Acknowledging that current scoring systems are useful but limited, the document’s original assessment combines procedure-specific impediments, major organ system compromise, comorbidities, patient frailty, and the STS predicted risk of mortality model. The risk scores—along with the specific risks and benefits—should be discussed with the patient in a shared decision-making process to determine the best therapy for the individual.

“Due to more knowledge regarding the natural history of untreated patients with severe VHD and better outcomes from surgery, we’ve lowered the threshold for operation to include more patients with asymptomatic severe valve disease,” said Dr. Nishimura. “Now, select patients with severe asymptomatic aortic stenosis and severe asymptomatic mitral regurgitation can be considered for intervention, depending on certain other factors, such as operative mortality and in the case of mitral regurgitation, the ability to achieve a durable valve repair.”

A First for TAVR

The document further addresses, for the first time, the use of TAVR. The introduction of TAVR and other new catheter-based therapies have made VHD management increasingly complex, as they have expanded patient options but increased the difficulty of discerning the risk-benefit ratio. The guidelines thus provide separate recommendations on both the timing and choice of these new interventions.

Using TAVR as an example, outcomes have significantly improved from the initial randomized trials of 2006 and the paradigm and question has changed from whether TAVR is appropriate for the sicker patients to whether TAVR will be the first choice for AS therapy in most patients. Granted, aspects of frailty and futility are yet to be determined, plus there remains a need for improvements relating to prevention of stroke, need for pacemaker, and paravalvular leak that must continue to develop.

As Dr. Nishimura put it at ACC.15, these really are guidelines for the 21st Century.

There is an ‘I’ in This Team

The guidelines support the application of a heart team approach, which is now a central concept in the care of patients with severe AS. However, questions recently have been raised about these teams.

In this case, there really is an ‘I’ in team—specifically, a Class I recommendation—and a ‘C’ in team, too: that is, its Level of Evidence (LOE) in both American and European professional society guidelines. Moreover, a heart team is required in the United States for reimbursement for TAVR, yet it comes with an LOE of C?

Recently in JACC, experts published a review paper, noting: “Although much has been written about the importance of a Heart Team approach (including by some of the current authors), we acknowledge that there is no clear consensus on its definition, desired goals, means of implementation, and, importantly, metrics to assess success and unintended consequences.”2

One of the authors of this review, Michael Mack, MD, FACC, of Baylor Scott & White Health in Dallas, TX, noted at ACC.15 that there are reasons for a heart team: the whole really is greater than the sum of its parts, it provides for immediate shared decision making with a patient-centered approach, there really still is a lot to learn and perplexing clinical decisions to make, and a team approach builds camaraderie and esprit-de-corps.

On the other hand, he said, there are reasons NOT to have a TAVR team: most patient decisions have become straightforward; logistics are still an issue; reimbursement for team services remains an issue; and TAVR procedures are becoming single-operator procedures.

Another recent article asked whether the emphasis on heart teams has “crossed the lines of evidence-based medicine.”3 The authors argue that the need for a new decision-making process in the choice of revascularization strategy should be further explored and supported by scientific evidence.

In the JACC review article, Dr. Mack and colleagues noted that wide-scale implementation of an intervention that may affect patient outcomes, including redesign of health care delivery, must be tested to validate effectiveness. There must be a continued focus on equitable reimbursement for services provided by diverse team members and further communication between centers regarding best practices for heart team implementation; formal quality improvement publications with specific details of delivery innovation also would be welcome.

With common definitions and metrics, the JACC authors noted that it may be possible to show that heart teams both enhance quality and reduce costs. They added that the impetus for investigating the utility of heart team interventions stems from the need to demonstrate value in the changing reimbursement environment, in part by documenting improvement in care delivery and related outcomes in a quality “report card.” Objective demonstrations of this sort, they added, will become increasingly important in discussions of payment for quality initiatives at both local and national levels.

References

  1. Nishimura RA, Otto CM, Bonow RO, et al. J Am Coll Cardiol. 2014;63:e57-e185.
  2. Coylewright M, Mack MJ, Holmes DR, Jr., O’Gara PT. J Am Coll Cardiol. 2015;65:1472-80.
  3. Rosenschein U, Nagler RM, Rofe A. Am J Cardiol. 2013;112:1516-9.

Clinical Topics: Cardiac Surgery, Invasive Cardiovascular Angiography and Intervention, Valvular Heart Disease, Aortic Surgery, Cardiac Surgery and VHD, Interventions and Structural Heart Disease, Interventions and Vascular Medicine

Keywords: Aortic Valve, Aortic Valve Stenosis, Heart Valve Diseases, Hemodynamics, Peripheral Arterial Disease, Stroke, Transcatheter Aortic Valve Replacement, CardioSource WorldNews Interventions


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