Severe prosthesis-patient mismatch after aortic valve replacement for aortic stenosis: Analysis of risk factors for early and long-term mortality

Background Severe prosthesis-patient mismatch (PPM) is considered to further decrease survival compared to moderate PPM. This study aimed to assess the impact of severe PPM on survival after aortic valve replacement (AVR). Methods We retrospectively studied 2404 consecutive patients with PPM who underwent first-time AVR for pure stenosis between January 2003 and December 2014. Mismatch was moderate for indexed effective valve orifice >0.65 to 220 g/m2 and concomitant coronary artery revascularization. After propensity score matching, conditional logistic regression analysis demonstrated no relationship between severe mismatch and increased mortality at 5 postoperative years (HR, 0.9; 95% CI, 0.7–1.6; p = 0.06), whereas it was significant at 10 postoperative years (HR, 1.9; 95% CI, 1.2–2.5; p = 0.03). During the follow-up, severe mismatch was associated with more frequent hospital readmissions for cardiac events (0.12 vs. 0.08 events/patient/year, p = 0.007). Conclusions Patients with severe mismatch had lower long-term survival and higher incidence of hospital readmissions for cardiac events. However, the effect of severe mismatch on outcome appeared mainly related to the preoperative risk profile of each patient. © 2016 Japanese College of Cardiolog