Synchronously stimulated skeletal muscle graft for left ventricular assistance. Case report

A 56-year-old man with chronic dilatation of the heart caused by cardiomyopathy (New York Heart Association functional class IV) was selected for cardiomyoplasty. The procedure was divided into two separate stages. In stage I the latissimus dorsi muscle was prepared for progressive stimulation. For this purpose two pacing leads were attached to the muscle, one at the proximal and the other at the distal end, and connected to a pulse-train generator, which was placed subcutaneously. A stimulation protocol was initiated in which the requirements of the latissimus dorsi muscle were periodically increased. In stage II the latissimus dorsi muscle was dissected to make a pedicle graft, which was introduced into the thorax and wrapped around the left ventricle. Pacing electrodes were sewn onto the pedicle graft in the same fashion as in stage I. Two sensing electrodes were fixed to the epicardium of the right ventricle, and the four leads were connected to a double-chambered pacemaker. Twelve days later, the pacemaker was programmed to a bipolar mode, VAT, and the latissimus dorsi muscle graft was synchronously stimulated in a 1:1 assist mode. The patient's status improved to New York Heart Association functional class II. Echocardiographic studies showed better contraction of the posterior wall of the left ventricle, as well as reduction in its diameters. Radioisotopic studies demonstrated a significant improvement in hemodynamic parameters. Cardiomyoplasty seems to be an alternative in those patients with severe cardiac insufficiency caused by cardiac dilation owing to cardiomyopathy.