Introduction: The incidence of structural valve deterioration (SVD) after aortic valve replacement (AVR) is generally established on the basis of reoperation due to valve failure. This approach may significantly underestimate the incidence of SVD. Objectives: to determine the incidence, predictors, timing, and impact of bioprosthetic (BP) valve hemodynamic deterioration (VHD) assessed by Doppler-echocardiography.
Methods: 1387 patients who underwent AVR and with at least 2 years of echo follow-up (62.2% male; 70.5±7.8 years old) were included in this retrospective study. Baseline echocardiography was performed at 4.1 (1.3-6.5) months post-AVR and echocardiographic follow-up was complete at 5-years post-AVR for 926 patients and at 10-years for 385 patients. VHD was defined as: ≥10mmHg increase in mean gradient (MG) and/or worsening of transprosthetic regurgitation ≥1/3 grade from baseline to last echocardiographic follow-up.
Results: VHD occurred in 428 patients (30.9%). After comprehensive adjustment, VHD (entered as time-dependent variable) was strongly and independently associated with mortality (HR: 2.18[1.86-2.57], p<0.001). Overall, independent predictors of VHD were diabetes (HR: 1.33[1.06-1.66], p=0.01), a MG ≥15mmHg at baseline echo (HR: 1.30[1.05-1.62], p=0.02), severe prosthesis-patient mismatch (HR: 1.85[1.12-2.87], p=0.02), and type of BP (stented vs. stentless BP, p<0.001). Interestingly, age was not a predictor. The VHD occurred early within <5 years after AVR in 181 patients, the predictors of this early SVD were: diabetes (p=0.01), active smoking status (p=0.01), renal insufficiency (p=0.01), post-AVR MG ≥15 mmHg (p=0.04) and ≥ mild transprosthetic regurgitation (p=0.04), and type of BP (stented vs. stentless, p=0.003). VHD occurred after 5 years in 247 patients, the predictors of late SVD were: female sex (p=0.03), use of coumadin (p=0.007) and type of BP (p<0.001).
Conclusions: In this large series of patients who underwent AVR with a BP, occurrence of VHD as identified by Doppler-echocardiographic is frequent (30%), and is associated with a 2-fold increase in mortality. Diabetes and renal insufficiency were associated with early SVD, whereas female sex and use of Coumadin were associated with late SVD.