Michael J. Mack M.D.

Baron, S. J., E. A. Magnuson, M. Lu, K. Wang, K. Chinnakondepalli, M. Mack, V. H. Thourani, S. Kodali, R. Makkar, H. C. Herrmann, S. Kapadia, V. Babaliaros, M. R. Williams, D. Kereiakes, A. Zajarias, M. C. Alu, J. G. Webb, C. R. Smith, M. B. Leon and D. J. Cohen (2019). “Health Status After Transcatheter Versus Surgical Aortic Valve Replacement in Low-Risk Patients With Aortic Stenosis.” J Am Coll Cardiol 74(23): 2833-2842.

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BACKGROUND: In patients with severe aortic stenosis (AS) at low surgical risk, treatment with transcatheter aortic valve replacement (TAVR) results in lower rates of death, stroke, and rehospitalization at 1 year compared with surgical aortic valve replacement; however, the effect of treatment strategy on health status is unknown. OBJECTIVES: This study sought to compare health status outcomes of TAVR versus surgery in low-risk patients with severe AS. METHODS: Between March 2016 and October 2017, 1,000 low-risk patients with AS were randomized to transfemoral TAVR using a balloon-expandable valve or surgery in the PARTNER 3 (Placement of Aortic Transcatheter Valves) trial. Health status was assessed at baseline and 1, 6, and 12 months using the KCCQ (Kansas City Cardiomyopathy Questionnaire), SF-36 (Short Form-36 Health Survey), and EQ-5D (EuroQoL). The primary endpoint was change in KCCQ-OS (KCCQ Overall Summary) score over time. Longitudinal growth curve modeling was used to compare changes in health status between treatment groups over time. RESULTS: At 1 month, TAVR was associated with better health status than surgery (mean difference in KCCQ-OS 16.0 points; p < 0.001). At 6 and 12 months, health status remained better with TAVR, although the effect was reduced (mean difference in KCCQ-OS 2.6 and 1.8 points respectively; p < 0.04 for both). The proportion of patients with an excellent outcome (alive with KCCQ-OS >/=75 and no significant decline from baseline) was greater with TAVR than surgery at 6 months (90.3% vs. 85.3%; p = 0.03) and 12 months (87.3% vs. 82.8%; p = 0.07). CONCLUSIONS: Among low-risk patients with severe AS, TAVR was associated with meaningful early and late health status benefits compared with surgery.

Sengupta, A., S. Zaid, N. Kamioka, J. Terre, M. Miyasaka, S. A. Hirji, M. Hensey, N. Geloo, G. Petrossian, N. Robinson, E. Sarin, L. Ryan, S. H. Yoon, C. W. Tan, O. K. Khalique, S. K. Kodali, T. Kaneko, P. B. Shah, S. C. Wong, A. Salemi, K. Sharma, J. A. Kozina, M. A. Szerlip, C. W. Don, S. Gafoor, M. Zhang, Z. Newhart, S. R. Kapadia, S. L. Mick, A. Krishnaswamy, A. Kini, H. Ahmad, S. L. Lansman, M. J. Mack, J. G. Webb, V. Babaliaros, V. H. Thourani, R. R. Makkar, M. B. Leon, I. George and G. H. L. Tang (2019). “Mid-Term Outcomes of Transcatheter Aortic Valve Replacement in Extremely Large Annuli With Edwards SAPIEN 3 Valve.” JACC Cardiovasc Interv Dec 18. [Epub ahead of print].

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OBJECTIVES: The aim of this study was to report the 1-year results of transcatheter aortic valve replacement (TAVR) with the Edwards SAPIEN 3 (S3) valve in extremely large annuli. BACKGROUND: Favorable 30-day outcomes of S3 TAVR in annuli >683 mm(2) have previously been reported. Pacemaker implantation rates were acceptable, and a larger left ventricular outflow tract and more eccentric annular anatomy were associated with increasing paravalvular leak. METHODS: From December 2013 to December 2018, 105 patients across 15 centers with mean area 721.3 +/- 36.1 mm(2) (range: 683.5 to 852.0 mm(2)) underwent TAVR using an S3 device. Clinical, anatomic, and procedural characteristics were analyzed. One-year survival and echocardiographic follow-up were reached in 94.3% and 82.1% of patients, respectively. Valve Academic Research Consortium-2 30-day and 1-year outcomes were reported. RESULTS: The mean age was 76.9 +/- 10.4 years, and Society of Thoracic Surgeons predicted risk score averaged 5.2 +/- 3.4%. One-year overall mortality and stroke rates were 18.2% and 2.4%, respectively. Quality-of-life index improved from baseline to 30 days and at 1 year (p < 0.001 for both). Mild paravalvular aortic regurgitation occurred in 21.7% of patients, while moderate or greater paravalvular aortic regurgitation occurred in 4.3%. Mild and moderate or severe transvalvular aortic regurgitation occurred in 11.6% and 0%, respectively. Valve gradients remained stable at 1 year. CONCLUSIONS: S3 TAVR in annular areas >683 mm(2) is feasible, with favorable mid-term outcomes.

Meduri, C. U., M. J. Reardon, D. S. Lim, E. Howard, G. Dunnington, D. P. Lee, D. Liang, R. Gooley, D. O’Hair, M. K. Ng, A. Walton, K. Spargias, D. Blackman, A. Coisne, D. Hildick-Smith, M. De Gouy, S. Chenoweth, S. Kar, P. M. McCarthy, N. Piazza, A. Qasam, R. P. Martin, M. B. Leon, M. J. Mack, D. H. Adams and V. Bapat (2019). “Novel Multiphase Assessment for Predicting Left Ventricular Outflow Tract Obstruction Before Transcatheter Mitral Valve Replacement.” JACC Cardiovasc Interv 12(23): 2402-2412.

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OBJECTIVES: This study proposes a physiologic assessment of left ventricular outflow tract obstruction (LVOTO) that accommodates changes in systolic flow and accounts for the dynamic neo-left ventricular outflow tract (LVOT). BACKGROUND: Patients considered for transcatheter mitral valve replacement trials often screen-fail because of the perceived risk of LVOTO. In the Intrepid Global Pilot Study, assumed risk of LVOTO was based on computed tomography estimates of the neo-LVOT area computed at end-systole. However, this may overestimate actual risk. METHODS: Retrospective analyses were performed for screen-failed patients for potential LVOTO (n = 33) and treated patients (n = 29) with available dynamic computed tomography. A multiphase assessment of the neo-LVOT area was performed and represented as: 1) multiphase average; and 2) early systolic value. Prospective evaluation was performed in 9 patients approved for enrollment with multiphase and early systole methods that would have previously screen-failed with the end-systolic approach. RESULTS: Of 166 patients screened for possible inclusion; 32 were screen-failed for nonanatomical reasons. Screen failure for assumed LVOTO risk occurred in 37 of 134 (27.6%) patients. Retrospective analysis indicated a potential enrollment increase of 11 of 33 (33.3%) and 18 of 33 (54.5%) patients using multiphase and early systolic assessment methods. In the prospective cohort, there were no clinical observations of LVOTO 30 days post-procedure, despite assumed risk based on end-systolic estimates. CONCLUSIONS: Multiphase, and specifically early systolic, assessment of the neo-LVOT may better determine risk of LVOTO with transcatheter mitral valve replacement compared with end-systolic estimates. This novel approach has the potential to significantly increase patient eligibility, with over one-half of patients previously screen-failed now eligible for treatment.

Mack, M. and P. Grayburn (2019). “A tale of two trials; chapter 2.” Eur J Heart Fail 21(12): 1635-1637.

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Last year witnessed the simultaneous publication of two randomized trials attempting to determine the benefits (if any) of the correction of moderate to severe or severe secondary (functional) mitral regurgitation (MR) with the MitraClip device (Abbott Inc, Santa Clara, CA, USA) in addition to guideline‐directed medical therapy (GDMT) in patients with heart failure (HF). One trial, the COAPT trial, was unequivocally positive demonstrating clear benefit in the primary effectiveness endpoint of all HF hospitalizations within 24 months.1 Also demonstrated in this trial was a mortality benefit and the trial met all 10 of the pre‐specified and powered secondary endpoints. However, the other trial, MITRA‐FR, conducted in approximately the same time frame in a similar study cohort of patients, found a diametrically opposite result with no demonstrable benefit in the primary effectiveness endpoint of death and HF hospitalization at 12 months.2 These discordant outcomes obtained using the same device to treat the same disease at roughly the same time has led to much debate and conjecture as how to explain these seemingly irreconcilable differences. (Excerpt from text of this commentary on “Percutaneous repair or medical treatment for secondary mitral regurgitation: outcomes at 2 years’’ by B. Iung et al., published in the same issue.)

Chhatriwalla, A. K., S. Vemulapalli, M. Szerlip, S. Kodali, R. T. Hahn, J. T. Saxon, M. J. Mack, G. Ailawadi, J. Rymer, P. Manandhar, A. S. Kosinski and P. Sorajja (2019). “Operator Experience and Outcomes of Transcatheter Mitral Valve Repair in the United States.” J Am Coll Cardiol 74(24): 2955-2965.

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BACKGROUND: Transcatheter mitral valve repair (TMVr) for the treatment of mitral regurgitation (MR) is a complex procedure that requires development of a unique skillset. OBJECTIVES: The purpose of this study was to examine the relationship between operator experience and procedural results of TMVr. METHODS: TMVr device procedures from the Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy registry were analyzed with operator case number as a continuous and categorical (1 to 25, 26 to 50, and >50) variable. Outcomes of procedural success, procedural time, and in-hospital procedural complications were examined. The learning curve for the procedure was evaluated using generalized linear mixed models adjusting for baseline clinical variables. RESULTS: All TMVr device procedures (n = 14,923) performed by 562 operators at 290 sites between November 2013 and March 2018 were analyzed. Optimal procedural success (less-than-or-equal-to 1+ residual MR without death or cardiac surgery) increased across categories of operator experience (63.9%, 68.4%, and 75.1%; p < 0.001), while procedural time and procedural complications decreased. Acceptable procedural success (less-than-or-equal-to 2+ residual MR without death or cardiac surgery) also increased with operator experience, but the differences were smaller (91.4%, 92.4%, and 93.8%; p < 0.001). These associations remained significant in adjusted, continuous variable analyses. Visual inflection points in the learning curves for procedural time, procedural success, and procedural complications were evident after approximately 50 cases, with continued improvements observed out to 200 cases. CONCLUSIONS: For TMVr device procedures, operator experience was associated with improvements in procedural success, procedure time, and procedural complications. The effect of operator experience was greater when considering the goal of achieving 1+ residual MR.