Background and aim of the study: The contribution of aortic valve (AV) cusp asymmetry to the future development of aortic stenosis (AS) has not been studied.
Methods: Of the 412,458 patients that underwent echocardiography between January 2003 and January 2011 at the Cleveland Clinic, 34,326 with aortic stenosis (AS) were identified from the Echocardiography Database. Among these patients, 5,830 had undergone echocardiography on more than one occasion. The review identified 71 patients who had tricuspid AV without stenosis, sclerosis or calcification, who met the study criteria, and who ultimately developed AS at a mean of 56.5 ± 19.4 months after the initial echocardiogram. Comprehensive echocardiographic AV cusp measurements taken from these echocardiograms were compared to those of 71 age- and gender-matched control subjects without AS.
Results: In the AS group, 11 patients (15.4%) had three equal-sized AV cusps, six (8.4%) had two equal-sized cusps, and 54 (76.1%) had three different-sized cusps. In the control group, 70 subjects (98.6%) had three equal-sized AV cusps, none had two equal-sized cusps, and one subject (1.4%) had three different-sized cusps. The average asymmetry index (AIx; %) among all the corresponding cusp measurements was significantly larger in the AS group (p = 0.000). Among the 71 AS patients, 32 developed mild AS, 30 moderate AS, and nine severe AS. The average AIx did not differ significantly based on AS severity.
Conclusion: The presence of asymmetry among AV cusps is strongly associated with the future development of AS. The present data suggest that a non-laminar flow secondary to an asymmetric valve may predispose the AV to become stenotic.