Volume-outcome relationship in emergency transcatheter aortic valve implantations in Germany

Abstract

Abstract Background An inverse volume-outcome relationship in transcatheter aortic valve implantation (TAVI) has been demonstrated in the literature but little is known about emergency cases. Methods All isolated balloon-expandable and self-expanding transfemoral TAVI in 2018 were identified using German national electronic health records. Additionally, those patients with an emergency admission were selected. Results A total of 17,295 patients received TAVI, 1,682 of these cases had an emergency admission. Of the emergency cases, 49.2% were female, mean age was 81.2 years and logistic EuroSCORE was 23.3%. Relatively more emergency cases were treated in lower volume centers than in higher volume centers (p<0.001): Centers performing <50 TAVI had an emergency admission rate of ∼15% while centers performing >200 TAVI were associated with a rate of ∼11%. Analyzing the outcomes for a volume increase per 10 emergency cases using propensity score adjustment, higher volume centers showed significantly better results than lower volume centers for in-hospital mortality (OR=0.872, p=0.043), major bleeding (OR=0.772, p=0.001), stroke (OR=0.816, p=0.044), mechanical ventilation >48h (OR=0.749, p=0.001), length of hospital stay (risk adjusted difference in days of hospitalization per 10 emergency admissions: −1.01 days, p<0.001), and reimbursement (risk adjusted difference in reimbursement per 10 emergency admissions: −€314.89, p<0.001). No correlation was seen in acute kidney injury (OR=0.951, p=0.104), postoperative delirium (OR=0.975, p=0.480), and permanent pacemaker implantation (OR=1.010, p=0.732). Conclusion In transfemoral TAVI, lower volume centers treat relatively more emergency cases in Germany, but higher volume centers provide significantly better outcomes regarding in-hospital mortality and complication rates as well as resource utilization parameters. Funding Acknowledgement Type of funding sources: None.