Michael J. Mack M.D.

Thourani, V. H., S. M. O’Brien, J. J. Kelly, D. J. Cohen, E. D. Peterson, M. J. Mack, D. M. Shahian, F. L. Grover, J. D. Carroll, J. M. Brennan, J. Forcillo, S. V. Arnold, S. Vemulapalli, S. Fitzgerald, D. R. Holmes, J. E. Bavaria and F. H. Edwards (2019). “Development and Application of a Risk Prediction Model for In-Hospital Stroke After Transcatheter Aortic Valve Replacement: A Report From The Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy Registry.” Ann Thorac Surg 107(4): 1097-1103.

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BACKGROUND: Stroke is a serious complication after transcatheter aortic valve replacement (TAVR), yet predictive models are not available. A new risk model for in-hospital stroke after TAVR was developed and used to estimate site-specific performance. METHODS: We included 97,600 TAVR procedures from 521 sites in The Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy Registry from July 2014 to June 2017. Association between baseline covariates and in-hospital stroke was estimated by logistic regression. Discrimination was evaluated by C-statistic. Calibration was tested internally via cross-validation. Hierarchical modeling was used to estimate risk-adjusted site-specific performance. RESULTS: Median age was 82 years, 44,926 (46.0%) were women, and 1,839 (1.9%) had in-hospital stroke. Covariates associated with stroke (odds ratio) included transapical access (1.44), access excluding transapical and transfemoral (1.77), prior stroke (1.57), prior transient ischemic attack (1.50), preprocedural shock, inotropes or mechanical assist device (1.48), smoking (1.28), porcelain aorta (1.23), peripheral arterial disease (1.21), age per 5 years (1.11), glomerular filtration rate per 5 mL/min (0.97), body surface area per m(2) (0.55 male; 0.43 female), and prior aortic valve (0.78) and nonaortic valvular (0.42) procedures. The C-statistic was 0.622. Calibration curves demonstrated agreement between observed and expected stroke rates. Hierarchical modeling showed 10 (1.9%) centers with significantly higher odds ratios for in-hospital stroke than their peers. CONCLUSIONS: A risk model for in-hospital stroke after TAVR was developed from The Society of Thoracic Surgeons/American College of Cardiology Transcatheter Valve Therapy Registry and used to estimate site-specific stroke performance. This model can serve as a valuable resource for quality improvement, clinical decision making, and patient counseling.

Hamandi, M., R. L. Smith, W. H. Ryan, P. A. Grayburn, A. Vasudevan, T. J. George, J. M. DiMaio, K. A. Hutcheson, W. Brinkman, M. Szerlip, D. O. Moore and M. J. Mack (2019). “Outcomes of Isolated Tricuspid Valve Surgery Have Improved in the Modern Era.” Ann Thorac Surg Apr 2. [Epub ahead of print].

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BACKGROUND: Surgery for isolated tricuspid valve (TV) disease remains relatively infrequent due to significant patient comorbidities and poor surgical outcomes. We reviewed our experience with isolated TV surgery in the current era to determine if outcomes have improved. METHODS: From 2007 through 2017, 685 TV operations were performed in a single institution of which 95 (13.9%) were isolated TV surgery. Patients were analyzed for disease etiology, risk factors, operative mortality and morbidity and long term survival. RESULTS: 95 patients underwent isolated TV surgery, an average of 9 patients/year increasing from an average of 5/year to 15/year during the study period. Surgery was reoperative in 41% (38/95), including 11.6% (11/95) with prior CABG and 29.4% (28/95) with prior valve surgery (9 tricuspid, 11 mitral, 2 aortic, 5 mitral/aortic and 1 mitral/tricuspid).Repair was performed in 71.6% (68/95) and replacement in 28.4% (27/95). Operative mortality was 3.2% (3/95) with no mortality in the most recent 73 patients over the last 6 years. Stroke occurred in 2.1% (2/95), acute kidney injury requiring dialysis in 5.3% (5/95) and need for new permanent pacemaker in 16.8% (16/95). CONCLUSIONS: In the current era with careful patient selection and periprocedural management, isolated TV surgery can be performed with lower morbidity and mortality than has traditionally been reported with good long term survival. These outcomes can also serve as a benchmark for catheter-based tricuspid valve intervention outcomes.

Dearani, J. A., T. K. Rosengart, M. B. Marshall, M. J. Mack, D. R. Jones, R. L. Prager and R. J. Cerfolio (2019). “Incorporating Innovation and New Technology Into Cardiothoracic Surgery.” Ann Thorac Surg 107(4): 1267-1274.

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The appropriate implementation of new technology, root cause analysis of “imperfect” outcomes, and the continuous reappraisal of postgraduate training are needed to improve the care of tomorrow’s patients. Healthcare delivery remains one of the most expensive sectors in the United States, and the application of new and expensive technology that is necessary for the advancement of this complex specialty must be aligned with providing the best care for our patients. There are a several pathways to innovation: One is partnering with industry and the other is the investigational laboratory. Innovation and the funding thereof come from both the public and private sector. Most new trials that are likely to impact cardiothoracic surgery are industry-sponsored trials to meet the requirements necessary for regulatory approval. Cost considerations are paramount when considering integration of innovative technology and treatments into a clinical cardiothoracic surgical practice. The value of any new innovation is determined by the quality divided by the cost, and lean initiatives maximize this equation. The importance and implications of conflict of interest have been a concern for physicians, particularly when new technology or procedures are incorporated into clinical practice, and full disclosures by medical professionals and others involved are essential. Our societies and associations provide a platform for presentation and peer-reviewed discussion of new procedures, innovations, and trials and provide a venue for the sharing of knowledge on the highest quality patient care through education and research.

Farkouh, M. E., M. Domanski, G. D. Dangas, L. C. Godoy, M. J. Mack, F. S. Siami, T. H. Hamza, B. Shah, G. G. Stefanini, M. S. Sidhu, J. F. Tanguay, K. Ramanathan, S. K. Sharma, J. French, W. Hueb, D. J. Cohen and V. Fuster (2019). “Long-Term Survival Following Multivessel Revascularization in Patients With Diabetes: The FREEDOM Follow-On Study.” J Am Coll Cardiol 73(6): 629-638.

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BACKGROUND: The FREEDOM (Future Revascularization Evaluation in Patients with Diabetes Mellitus: Optimal Management of Multivessel Disease) trial demonstrated that for patients with diabetes mellitus (DM) and multivessel coronary disease (MVD), coronary artery bypass grafting (CABG) is superior to percutaneous coronary intervention with drug-eluting stents (PCI-DES) in reducing the rate of major adverse cardiovascular and cerebrovascular events after a median follow-up of 3.8 years. It is not known, however, whether CABG confers a survival benefit after an extended follow-up period. OBJECTIVES: The purpose of this study was to evaluate the long-term survival of DM patients with MVD undergoing coronary revascularization in the FREEDOM trial. METHODS: The FREEDOM trial randomized 1,900 patients with DM and MVD to undergo either PCI with sirolimus-eluting or paclitaxel-eluting stents or CABG on a background of optimal medical therapy. After completion of the trial, enrolling centers and patients were invited to participate in the FREEDOM Follow-On study. Survival was evaluated using Kaplan-Meier analysis, and Cox proportional hazards models were used for subgroup and multivariate analyses. RESULTS: A total of 25 centers (of 140 original centers) agreed to participate in the FREEDOM Follow-On study and contributed a total of 943 patients (49.6% of the original cohort) with a median follow-up of 7.5 years (range 0 to 13.2 years). Of the 1,900 patients, there were 314 deaths during the entire follow-up period (204 deaths in the original trial and 110 deaths in the FREEDOM Follow-On). The all-cause mortality rate was significantly higher in the PCI-DES group than in the CABG group (24.3% [159 deaths] vs. 18.3% [112 deaths]; hazard ratio: 1.36; 95% confidence interval: 1.07 to 1.74; p = 0.01). Of the 943 patients with extended follow-up, the all-cause mortality rate was 23.7% (99 deaths) in the PCI-DES group and 18.7% (72 deaths) in the CABG group (hazard ratio: 1.32; 95% confidence interval: 0.97 to 1.78; p = 0.076). CONCLUSIONS: In patients with DM and MVD, coronary revascularization with CABG leads to lower all-cause mortality than with PCI-DES in long-term follow-up. (Comparison of Two Treatments for Multivessel Coronary Artery Disease in Individuals With Diabetes [FREEDOM]; NCT00086450).

Baron, S. J., K. Wang, J. A. House, E. A. Magnuson, M. R. Reynolds, R. Makkar, H. C. Herrmann, S. Kodali, V. H. Thourani, S. Kapadia, L. Svensson, M. J. Mack, D. L. Brown, M. J. Russo, C. R. Smith, J. Webb, C. Miller, M. B. Leon and D. J. Cohen (2019). “Cost-Effectiveness of Transcatheter Versus Surgical Aortic Valve Replacement in Patients With Severe Aortic Stenosis at Intermediate Risk.” Circulation 139(7): 877-888.

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BACKGROUND: In patients with severe aortic stenosis (AS) at intermediate surgical risk, treatment with transcatheter aortic valve replacement (TAVR) or surgical aortic valve replacement (SAVR) results in similar rates of death or stroke at 2 years. Whether TAVR is cost-effective compared with SAVR for intermediate-risk patients remains uncertain. METHODS: Between 2011 and 2014, 3110 intermediate-risk AS patients were treated with TAVR or SAVR in the PARTNER 2 trial (Placement of Aortic Transcatheter Valves 2). A total of 2032 patients were randomized to receive TAVR using the SAPIEN XT valve (XT-TAVR) or SAVR in the PARTNER 2A trial, whereas the PARTNER S3i registry included an additional 1078 patients treated with TAVR using the SAPIEN 3 valve (S3-TAVR), which offers a lower delivery profile and sealing skirt designed to reduce paravalvular regurgitation compared with XT-TAVR. Procedural costs were estimated using measured resource utilization. Other in-trial costs were assessed by linkage of trial data with Medicare claims (n=2333) or by linear regression models for unlinked patients (n=682). Health utilities were estimated using the EQ-5D at baseline and 1, 12, and 24 months. Using a Markov model informed by in-trial costs, utilities, and survival data, lifetime cost-effectiveness from the perspective of the US healthcare system was estimated in terms of cost per quality-adjusted life-year gained. RESULTS: Although procedural costs were approximately $20 000 higher with TAVR than SAVR, total cost differences for the index hospitalization were only $2888 higher with XT-TAVR ( P=0.014) and were $4155 lower with S3-TAVR ( P<0.001) owing to reductions in length of stay with TAVR. Follow-up costs were significantly lower with XT-TAVR (Delta=-$9304; P<0.001) and S3-TAVR (Delta=-$11 377; P<0.001) than with SAVR. Over a lifetime horizon, TAVR was projected to lower total costs by $8000 to $10 000 and to increase quality-adjusted survival by 0.15 to 0.27 years. XT-TAVR and S3-TAVR were found to be economically dominant compared with SAVR in 84% and 97% of bootstrap replicates, respectively. CONCLUSIONS: Among intermediate-risk AS patients, TAVR is projected to be economically dominant from the perspective of the US healthcare system by providing both greater quality-adjusted life expectancy and lower long-term costs than SAVR. If long-term data demonstrate comparable late mortality with TAVR and SAVR, these findings suggest that TAVR might be the preferred treatment strategy for intermediate-risk AS patients based on both clinical and economic considerations. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov . Unique identifier: NCT01314313.