Commissural geometry and cusp fusion insights to guide bicuspid aortic valve repair

In general, classification of a disease has proven to be advantageous for disease management. This may also be valid for the bicuspid aortic valve, because the term "bicuspid aortic valve" stands for a common congenital aortic valve malformation with heterogeneous morphologic phenotypes and function resulting in different treatment strategies. We attempted to establish a classification system based on a 5-year data collection of surgical specimens. Between 1999 and 2003 a precise description of valve pathology was obtained from operative reports of 304 patients with a diseased bicuspid aortic valve. Several different characteristics of bicuspid aortic valves were tested to generate a pithy and easily applicable classification system. Three characteristics for a systematic classification were found appropriate: (1) number of raphes, (2) spatial position of cusps or raphes, and (3) functional status of the valve. The first characteristic was found to be the most significant and therefore termed "type." Three major types were identified: type 0 (no raphe), type 1 (one raphe), and type 2 (two raphes), followed by two supplementary characteristics, spatial position and function. These characteristics served to classify and codify the bicuspid aortic valves into three categories. Most frequently, a bicuspid aortic valve with one raphe was identified (type 1, n = 269). This raphe was positioned between the left (L) and right (R) coronary sinuses in 216 (type 1, L/R) with a hemodynamic predominant stenosis (S) in 119 (type 1, L/R, S). Only 21 patients had a "purely" bicuspid aortic valve with no raphe (type 0). A classification system for the bicuspid aortic valve with one major category ("type") and two supplementary categories is presented. This classification, even if used in the major category (type) alone, might be advantageous to better define bicuspid aortic valve disease, facilitate scientific communication, and improve treatment.

Reconstruction of the regurgitant bicuspid aortic valve has been performed for >10 years, but there is limited information on long-term results. We analyzed our results to determine the predictors of suboptimal outcome. Between November 1995 and December 2008, 316 patients (age, 49±14 years; male, 268) underwent reconstruction of a regurgitant bicuspid aortic valve. Intraoperative assessment included extent of fusion, root dimensions, circumferential orientation of the 2 normal commissures (>160°, ≤160°), and effective height after repair. Cusp pathology was treated by central plication (n=277), triangular resection (n=138), or pericardial patch (n=94). Root dilatation was treated by subcommissural plication (n=100), root remodeling (n=122), or valve reimplantation (n=2). All patients were followed up echocardiographically (cumulative follow-up, 1253 years; mean, 4±3.1 years). Clinical and morphological parameters were analyzed for correlation with 10-year freedom from reoperation with the Cox proportional hazards model. Hospital mortality was 0.63%; survival was 92% at 10 years. Freedom from reoperation at 5 and 10 years was 88% and 81%; freedom from valve replacement, 95% and 84%. By univariable analysis, statistically significant predictors of reoperation were age (hazard ratio [HR]=0.97), aortoventricular diameter (HR=1.24), effective height (HR=0.76), commissural orientation (HR=0.95), use of a pericardial patch (HR=7.63), no root replacement (HR=3.80), subcommissural plication (HR=2.07), and preoperative aortic regurgitation grade 3 or greater. By multivariable analysis, statistically significant predictors for reoperation were age (HR=0.96), aortoventricular diameter (HR=1.30), effective height (HR=0.74), commissural orientation (HR=0.96), and use of a pericardial patch (HR=5.16). Reconstruction of bicuspid aortic valve can be performed reproducibly with good early results. Recurrence and progression of regurgitation, however, may occur, depending primarily on anatomic features of the valve.

To describe a clinicopathologic study of a large group of congenitally bicuspid aortic valves surgically excised at a single institution. The medical charts and bicuspid valves from patients undergoing aortic valve replacement at Mayo Clinic Rochester between 1991 and 1996 were retrospectively reviewed. The age of the 542 patients ranged from 1 to 86 years (mean, 61), and 372 (69%) were men. Among these, 409 (75%) had pure aortic stenosis (AS), 73 (13%) had pure aortic insufficiency (regurgitation) (AI), 53 (10%) had combined AS and AI, and 7 (1%) had normal function. The mean age was higher for those with AS than AI (65 versus 46 years; P < 0.001), whereas the male-to-female ratio was higher for AI than AS (17.3:1 versus 1.7:1; P < 0.001). The two cusps were not equal in size in 95%, and a raphe was present in 76% (67% typical, 9% atypical). Raphal position was described in 315 and was between the right and left cusps in 270 (86%). Raphal absence occurred more often in valves with equal-sized cusps than unequal (33% versus 14%; P = 0.005). Moderate to severe calcification affected valves with AS more frequently than AI (99% versus 41%; P < 0.001). In contrast, annular dilatation was associated with AI more than AS (48% versus 11%; P < 0.001). Acquired commissural fusion involved valves with combined AS and AI more often than the other functional states (31% versus 14%; P = 0.002). Sixteen patients (age range, 18 to 78 years; 13 men) had infective endocarditis (6 active, 10 healed), including 10 with AI (9 men), 3 with AS plus AI, 2 with AS, and 1 with normal function but embolization. Functionally, the most common fate of congenitally bicuspid aortic valves was calcific stenosis with or without regurgitation (85%). Because approximately 4 million US citizens have bicuspid valves and because valve replacement is currently the only treatment of symptomatic AS, this disorder will continue to affect health-care costs.