Background: The aim of this study was to evaluate the midterm results of a modified button-Bentall operation (modified-bB) specifically designed to incorporate any type of prosthetic valve in composite conduit aortic root replacement.
Methods: Between 1991 and 2000, a total of 135 patients underwent modified-bB for annuloaortic ectasia (74 patients), type A dissection (31), or aortic aneurysm without dissection (30). Of these, 34 were emergencies (25.2%). A total of 50 bioprostheses (study group 1) and 85 bileaflet mechanical prostheses (study group 2) were implanted. Group 1 mean age was 66.9 +/- 7.4 years versus 51.5 +/- 12.1 years in group 2 (p < 0.001). Composite-conduit creation occurred during proximal suture line construction as a single-step maneuver. Interrupted extracardiac polyester mattress sutures sequentially entered the aortic annulus, the prosthetic valve ring, and the vascular graft 7 mm from its free edge (miniskirt). Running monofilament suture line secured proximal hemostasis, buttressing aortic remnants and graft edge. Coronary reimplantation was accomplished in all cases by the button technique. Concomitant procedures were performed in 51 patients (37.8%).
Results: The 30-day mortality was 5.18% (7/135 patients). Eight patients (5.9%) required revision for proximal (1 patient), coronary button (3), or distal (4) anastomosis leakage. Three patients (2.2%) perioperatively developed nonfatal inferior myocardial infarction. Kaplan-Meier 9-year survival is 91.8% +/- 0.026 SE with 88.1% (95% confidence limits 71.7% to 95.5%) reoperation freedom. According to the Cox proportional hazard method, stratification of the risk for death according to prosthesis type indicates previous operation (p = 0.001) and emergency (p = 0.0465) as independent predictors of hospital mortality. Associated procedures to modified-bB increased risk of reoperation (p = 0.031).
Conclusions: Modified-bB was associated with low mortality, excellent midterm survival, and freedom from reoperation. Absence of valve-to-graft tapering, reduced coronary button anastomosis tension, and prosthesis selection according to patient profile, are apparent advantages of modified-bB.