Vinod H Thourani1, James M Brennan2, J James Edelman3, Dylan Thibault2, Oliver K Jawitz2, Joseph E Bavaria4, Robert S D Higgins5, Joseph F Sabik6, Richard L Prager7, Joseph A Dearani8, Thomas E MacGillivray9, Vinay Badhwar10, Lars G Svensson11, Michael J Reardon9, David M Shahian12, Jeffrey P Jacobs13, Gorav Ailawadi7, Wilson Y Szeto4, Nimesh Desai4, Eric E Roselli11, Y Joseph Woo14, Sreek Vemulapalli2, John D Carroll15, Pradeep Yadav16, S Chris Malaisrie17, Mark Russo18, Tom C Nguyen19, Tsuyoshi Kaneko20, Gilbert Tang21, Marc Ruel22, Joanna Chikwe23, Richard Lee24, Robert H Habib25, Isaac George26, Martin B Leon27, Michael J Mack28. 1. Department of Cardiovascular Surgery and Cardiology, Marcus Valve Center, Piedmont Heart Institute, Atlanta, Georgia. Electronic address: vinod.thourani@piedmont.org. 2. Department of Medicine, Duke University, Durham, North Carolina. 3. Department of Cardiac Surgery, Fiona Stanley Hospital, Perth, Australia. 4. Division of Cardiothoracic Surgery, University of Pennsylvania, Philadelphia, Pennsylvania. 5. Division of Cardiothoracic Surgery, Johns Hopkins University, Baltimore, Maryland. 6. Division of Cardiac Surgery, Case Western University, Cleveland, Ohio. 7. Department of Cardiac Surgery, University of Michigan, Michigan. 8. Department of Cardiac Surgery, Mayo Clinic, Rochester, Minnesota. 9. Department of Cardiac Surgery, Methodist Hospital, Houston, Texas. 10. Division of Cardiothoracic Surgery, West Virginia University, Morgantown, West Virginia. 11. Heart and Vascular Institute, Cleveland Clinic Foundation, Cleveland, Ohio. 12. Division of Surgery, Massachusetts General Hospital, Harvard University, Boston, Massachusetts. 13. Division of Thoracic and Cardiovascular Surgery, Department of Surgery, University of Florida, Gainesville, Florida. 14. Department of Cardiac Surgery, Stanford University, Palo Alto, California. 15. Division of Cardiology, University of Colorado, Aurora, Colorado. 16. Department of Cardiovascular Surgery and Cardiology, Marcus Valve Center, Piedmont Heart Institute, Atlanta, Georgia. 17. Division of Cardiac Surgery, Northwestern University, Chicago, Illinois. 18. Division of Cardiac Surgery, RWJ Barnabas Health, New Brunswick, New Jersey. 19. Division of Cardiac Surgery, University of California San Francisco, San Francisco, California. 20. Division of Cardiac Surgery, Brigham and Women's Hospital, Harvard University, Boston, Massachusetts. 21. Department of Cardiac Surgery, Mt Sinai Medical Center, New York, New York. 22. Department of Cardiac Surgery, Ottawa Heart Institute, Ottawa, Ontario, Canada. 23. Department of Cardiac Surgery, Cedars Sinai Heart Institute, Los Angeles, California. 24. Department of Cardiac Surgery, Augusta University, Augusta, Georgia. 25. Society of Thoracic Surgeons, Chicago, Illinois. 26. Division of Cardiac Surgery, Columbia University, New York, New York. 27. Division of Cardiology, Columbia University, New York, New York. 28. Department of Cardiac Surgery, Baylor, Scott and White, Plano, Dallas, Texas.
Abstract
BACKGROUND: The relationship between institutional volume and operative mortality after surgical aortic valve replacement (SAVR) remains unclear. METHODS: From January 2013 to June 2018, 234 556 patients underwent isolated SAVR (n = 144 177) or SAVR with coronary artery bypass grafting (CABG) (n = 90 379) within the Society of Thoracic Surgeons Adult Cardiac Surgery Database. The association between annualized SAVR volume (group 1 [1-25 SAVRs], group 2 [26-50 SAVRs], group 3 [51-100 SAVRs], and group 4 [>100 SAVRs]) and operative mortality and composite major morbidity or mortality was assessed. Random effects models were used to evaluate whether historical (2013-2015) SAVR volume or risk-adjusted outcomes explained future (2016-2018) risk-adjusted outcomes. RESULTS: The annualized median number of SAVRs per site was 35 (interquartile range, 22-59; isolated aortic valve replacement [AVR], 20; AVR with CABG, 13). Among isolated SAVR cases, the mean operative mortality and composite morbidity or mortality were 1.5% and 9.7%, respectively, at the highest-volume sites (group 4), with significantly higher rates among progressively lower-volume groups (P trend < .001). After adjustment, lower-volume centers had increased odds of operative mortality (group 1 vs group 4 [reference]: adjusted odds ratio [AOR] for SAVR, 2.24 [95% CI, 1.91-2.64]; AOR for SAVR with CABG, 1.96 [95% CI, 1.67-2.30]) and major morbidity or mortality (AOR for SAVR, 1.53 [95% CI, 1.39-1.69]; AOR for SAVR with CABG, 1.46 [95% CI, 1.32-1.61]) compared with the highest-volume institutions. Substantial variation in outcomes was observed across hospitals within each volume category, and prior outcomes explained a greater proportion of hospital operative outcomes than did prior volume. CONCLUSIONS: Operative outcomes after SAVR with or without CABG is inversely associated with institutional procedure volumes; however, prior outcomes are more predictive of future outcomes than is prior volume. Given the excellent outcomes observed at many lower-volume hospitals, procedural outcomes may be preferable to procedural volumes as a quality metric.
BACKGROUND: The relationship between institutional volume and operative mortality after surgical aortic valve replacement (SAVR) remains unclear. METHODS: From January 2013 to June 2018, 234 556 patients underwent isolated SAVR (n = 144 177) or SAVR with coronary artery bypass grafting (CABG) (n = 90 379) within the Society of Thoracic Surgeons Adult Cardiac Surgery Database. The association between annualized SAVR volume (group 1 [1-25 SAVRs], group 2 [26-50 SAVRs], group 3 [51-100 SAVRs], and group 4 [>100 SAVRs]) and operative mortality and composite major morbidity or mortality was assessed. Random effects models were used to evaluate whether historical (2013-2015) SAVR volume or risk-adjusted outcomes explained future (2016-2018) risk-adjusted outcomes. RESULTS: The annualized median number of SAVRs per site was 35 (interquartile range, 22-59; isolated aortic valve replacement [AVR], 20; AVR with CABG, 13). Among isolated SAVR cases, the mean operative mortality and composite morbidity or mortality were 1.5% and 9.7%, respectively, at the highest-volume sites (group 4), with significantly higher rates among progressively lower-volume groups (P trend < .001). After adjustment, lower-volume centers had increased odds of operative mortality (group 1 vs group 4 [reference]: adjusted odds ratio [AOR] for SAVR, 2.24 [95% CI, 1.91-2.64]; AOR for SAVR with CABG, 1.96 [95% CI, 1.67-2.30]) and major morbidity or mortality (AOR for SAVR, 1.53 [95% CI, 1.39-1.69]; AOR for SAVR with CABG, 1.46 [95% CI, 1.32-1.61]) compared with the highest-volume institutions. Substantial variation in outcomes was observed across hospitals within each volume category, and prior outcomes explained a greater proportion of hospital operative outcomes than did prior volume. CONCLUSIONS: Operative outcomes after SAVR with or without CABG is inversely associated with institutional procedure volumes; however, prior outcomes are more predictive of future outcomes than is prior volume. Given the excellent outcomes observed at many lower-volume hospitals, procedural outcomes may be preferable to procedural volumes as a quality metric.