The Incidence and Consequence of Prosthesis-Patient Mismatch After Surgical Aortic Valve Replacement.

Background: The goal of this study was to determine the relationship of prosthesis-patient mismatch (PPM) with long-term survival and to assess whether growing concern about PPM has resulted in a decreased incidence over time.

Methods: Using The Society of Thoracic Surgeons Adult Cardiac Surgery Database, we identified 59,779 patients ≥65 years old who underwent isolated surgical aortic valve replacement (AVR) between 2004 and 2014. The degree of PPM was calculated using literature-derived effective orifice areas for commonly used valves. Outcomes to 10 years were stratified by degree of PPM.

Results: The distribution of PPM was as follows: 35%, none (n = 21,053); 54%, moderate (n = 32,243); and 11%, severe (n = 6,483). Compared with patients with no PPM, patients with moderate or severe PPM had a significantly increased risk of readmission for heart failure (hazard ratio [HR], 1.15; 95% confidence interval [CI], 1.09 to 1.21; HR, 1.37; 95% CI, 1.26 to 1.48) and redo AVR (HR, 1.41; 95% CI, 1.13 to 1.77; HR, 2.68; 95% CI, 2.01 to 3.56) for moderate or severe PPM, respectively. Survival was significantly worse for any degree of PPM (moderate to none: HR, 1.08; 95% CI, 1.05 to 1.12; severe to none: HR, 1.32; 95% CI, 1.25 to 1.39), with 10-year adjusted survival rates of 46%, 43%, and 35% for none, moderate, and severe, respectively (p < 0.001). The incidence of severe PPM decreased by 55% over the study period, from 13.8% in 2004 to 6.2% in 2014.

Conclusions: Any degree of PPM significantly decreased long-term survival and increased readmission rates for both heart failure and reoperation for AVR. Temporal trends show a significant decrease in the incidence of PPM over the past decade.