Objectives: We sought to determine whether an AVR performed though a partial upper hemisternotomy ("mini-AVR") resulted in a greater incidence of patient-prosthesis mismatch (PPM) than those through a full median sternotomy ("AVR").
Methods: Patients undergoing isolated aortic valve replacement from 2008 to 2013 were identified. Moderate PPM was defined as an in vivo effective orifice area ≤0.85 cm(2)/m(2) body surface area; severe PPM was defined as ≤0.65 cm(2)/m(2). A propensity score-matched analysis was utilized to compare the incidence of PPM between these groups.
Results: Of the 630 patients undergoing aortic valve surgery, 90 (14.3%) received mini-AVRs and 540 (85.7%) received regular AVRs. After propensity matching, we established two cohorts of 85 patients receiving each procedure. Both cohorts were similar with regard to all preoperative covariates including mean age (65.5 vs. 65.1, p = 0.85), diabetes (17.7 vs. 22.4%), mean BMI (28.3 vs. 28.6, p = 0.73), mean EF (56.9 vs. 55.6, p = 0.43), proportion of patients with aortic stenosis (70.6 vs. 71.8%, p = 1.00), preoperative valve area (0.88 vs. 0.93 cm(2), p = 0.67), and proportion who received a bioprosthesis (85.9 vs. 83.5%, p = 0.59). Postoperatively, 27.4% of mini-AVRs and 26.8% of AVRs had moderate PPM (p = 0.93); 2.4 and 1.2% had severe PPM (p = 0.66). Kaplan-Meier analysis also failed to reveal a difference in 1-year survival between mini and regular AVRs (93.7 vs. 90.5%, p = 0.49).
Conclusions: After propensity matching, mini-AVRs are not associated with a greater incidence of PPM than regular AVRs. Severe PPM was rare across both procedure types in this surgical series.
Keywords: Aortic valve; Aortic valve replacement; Hemisternotomy; Median sternotomy; Patient–prosthesis mismatch.