Altered left ventricular mechanics in patients with valvular aortic stenosis and coarction of the aorta: effects on systolic performance and late outcome.

Abstract

Despite similar degrees of left ventricular systolic hypertension shortening characteristics are usually greater in patients with congenital valvular aortic stenosis (VAS) than in patients with coarctation of the aorta (CoA). We hypothesized that these dissimilarities were caused by differences in myocardial mechanics rather than by alterations in contractile state. Eleven patients with VAS (ages 6 to 41 years) and 11 with CoA were matched for age, body surface area, and peak systolic ejection gradient. Results were compared with data from 22 normal subjects matched for age and body surface area. Echocardiographic tracings of the left ventricle were recorded in conjunction with left ventricular pressure measurements (VAS) or calibrated carotid pulse tracings (CoA and normal subjects). Peak and end-systolic wall stresses as well as left ventricular shortening fraction (% delta D) and rate-corrected velocity of fiber shortening (Vcfc) were calculated. No differences for left ventricular dimensions, heart rate or peak wall stress were present. Ventricular peak systolic pressures and wall mass were higher for the patients with VAS or CoA than for the normal subjects (p less than .001). These parameters did not differ between the VAS and CoA groups. The patients with VAS had higher % delta D and Vcfc than either the CoA or normal groups (p less than .01). Afterload, as quantified by end-systolic stress, was 41% lower than normal for the patients with VAS (p less than .001) and 13% higher than normal for those with CoA (p less than .05).(ABSTRACT TRUNCATED AT 250 WORDS)