Association Between Hospital Volume and 30-Day Readmissions Following Transcatheter Aortic Valve Replacement.

Importance: With the approval of transcatheter aortic valve replacement (TAVR) for patients with severe symptomatic aortic stenosis at intermediate surgical risk, TAVR volume is projected to increase exponentially in the United States. The 30-day readmission rate for TAVR was recently reported at 17.9%. The association between institutional TAVR volume and the 30-day readmission metric has not been examined. Objective: To assess the association between hospital TAVR volume and 30-day readmission. Design, Setting, and Participants: In this observational study, we used the 2014 Nationwide Readmissions Database to identify hospitals with established TAVR programs (performing at least 5 TAVRs in the first quarter of 2014). Based on annual TAVR volume, hospitals were classified as low (<50), medium (≥50 to <100), and high (≥100) volume. Rates, causes, and costs of 30-day readmissions were compared between low-, medium-, and high-volume hospitals. Data were analyzed from November to December 2016. Exposure: Transcatheter aortic valve replacement. Main Outcomes and Measures: Thirty-day readmissions. Results: Of 129 hospitals included in this study, 20 (15.5%) were categorized as low volume, 47 (36.4%) as medium volume, and 62 (48.1%) as high volume. Of 16 252 index TAVR procedures, 663 (4.1%), 3067 (18.9%), and 12 522 (77.0%) were performed at low-, medium-, and high-volume hospitals, respectively. Thirty-day readmission rates were significantly lower in high-volume compared with medium-volume (adjusted odds ratio, 0.76; 95% CI, 0.68-0.85; P < .001) and low-volume (adjusted odds ratio, 0.75; 95% CI, 0.60-0.92; P = .007) hospitals. Noncardiac readmissions were more common in low-volume hospitals (65.6% vs 60.6% in high-volume hospitals), whereas cardiac readmissions were more common in high-volume hospitals (39.4% vs 34.4% in low-volume hospitals). There were no significant differences in length of stay and costs per readmission among the 3 groups (mean [SD], 5.5 [5.0] days vs 5.9 [7.5] days vs 6.0 [5.8] days; P = .74, and $13 886 [18 333] vs $14 135 [17 939] vs $13 432 [15 725]; P = .63, respectively). Conclusions and Relevance: We report for the first time, to our knowledge, an inverse association between hospital TAVR volume and 30-day readmissions. Lower readmission at higher-volume hospitals was associated with significantly lower cost to the health care system.