Long-Term Outcomes of Patients Undergoing Aortic Root Replacement With Mechanical Versus Bioprosthetic Valves: Meta-Analysis of Reconstructed Time-to-Event Data

Abstract

BACKGROUND: An aspect not so clear in the scenario of aortic surgery is how patients fare after composite aortic valve graft replacement (CAVGR) depending on the type of valve (bioprosthetic versus mechanical). We performed a study to evaluate the long-term outcomes of both strategies comparatively. METHODS AND RESULTS: Pooled meta-analysis of Kaplan-Meier– derived time-to-event data from studies with follow-up for overall survival (all-cause death), event-free survival (composite end point of cardiac death, valve-related complications, stroke, bleeding, embolic events, and/or endocarditis), and freedom from reintervention. Twenty-three studies met our eligibility criteria, including 11 428 patients (3786 patients with mechanical valves and 7642 patients with bioprosthetic valve). The overall population was mostly composed of men (mean age, 45.5–75.6 years). In comparison with patients who underwent CAVGR with bioprosthetic valves, patients undergoing CAVGR with mechanical valves presented no statistically significant difference in the risk of all-cause death in the first 30 days after the procedure (hazard ratio [HR], 1.24 [95% CI, 0.95–1.60]; P=0.109), but they had a significantly lower risk of all-cause mortality after the 30-day time point (HR, 0.89 [95% CI, 0.81– 0.99]; P=0.039) and lower risk of reintervention (HR, 0.33 [95% CI, 0.24– 0.45]; P<0.001). Despite its increased risk for the composite end point in the first 6 years of follow-up (HR, 1.41 [95% CI, 1.09–1.82]; P=0.009), CAVGR with mechanical valves is associated with a lower risk for the composite end point after the 6-year time point (HR, 0.46 [95% CI, 0.31– 0.67]; P<0.001). CONCLUSIONS: CAVGR with mechanical valves is associated with better long-term outcomes in comparison with CAVGR with bioprosthetic valves.