Clinical cardiomyoplasty: Review of the ten-year United States experience

Background. Clinical trials of dynamic cardiomyoplasty were pioneered at Allegheny General Hospital beginning in September 1985. Data from 9 years of experience with the procedure at this institution and more recent data from newer cardiomyoplasty centers have been analyzed for outcome analysis and future trends. Methods. Each patient underwent a cardiomyoplasty procedure using the left or right latissimus dorsi muscle. Thirty-four patients were studied at Allegheny: 5 patients implanted with dual chamber pacemakers as single stimulus myostimulators, 11 patients composing the phase I Food and Drug Administration trial of the Medtronic burst myostimulatur, and 18 patients entered in the phase II Medtronic trial, Patients from seven additional centers entered the phase II trial in 1991. Fifty-seven patients completed follow-up studies to 1 year after operation in this trial. Results. Operative mortality was 5/57 (11%) in the American phase II group and 5/34 (15%) in the Allegheny group (1/18, 6% for Allegheny phase II). Nineteen patients (19/57, 33%) from the combined phase II population died in the first year, and 10/34 (29%) in the Allegheny study. The predominant cause of postdischarge death was arrhythmia (12/19, 63% American; 7/10, 70% Allegheny). In all groups significant improvement was seen in quality of life and functional class. Phase II patients demonstrated significant increases in ejection fraction and stroke work. Conclusions. Failure to sustain improvement and arrhythmia-related death are complex challenges for this procedure; however, realistic solutions have been proposed and are under investigation.