GIRDLING EFFECT OF NONSTIMULATED CARDIOMYOPLASTY ON LEFT-VENTRICULAR FUNCTION

The precise hemodynamic effects of latissimus dorsi cardiomyoplasty ha ve not been well characterized. We prospectively studied 11 mongrel do gs using a rapid ventricular pacing model of congestive heart failure. Six dogs received a nonstimulated left latissimus dorsi cardiomyoplas ty wrap, and 5 control dogs were paced only. Two-dimensional transthor acic echocardiography was performed on all dogs at baseline and then w eekly for 4 weeks. Measurements obtained included left ventricular dia meters, lengths, volumes, and ejection fractions. Progressive left ven tricular enlargement, increase in volumes, and worsening ejection frac tions developed in both groups. However, less left ventricular dilatat ion and higher ejection fractions were seen in dogs that received a ca rdiomyoplasty wrap. A nonstimulated cardiomyoplasty wrap significantly attenuated the degree of left ventricular enlargement, increase in le ft ventricular volumes, and decrease in ejection fraction in a rapid p acing model of congestive heart failure. Apart from its effect on syst olic augmentation with a stimulated muscle wrap, cardiomyoplasty may h ave an important ''girdling'' effect on the left ventricle that preven ts dilatation and deterioration of left ventricular function.