STUDY OF MUSCULAR AND VENTRICULAR-FUNCTION IN DYNAMIC CARDIOMYOPLASTY- A 10-YEAR FOLLOW-UP

Background: The basic physiologic principle underlying cardiomyoplasty is long-term electrostimulation of a latissimus dorsi muscle (LDM) wr apped around the heart to obtain a phasic activity that could be integ rated with ventricular kinetics. The aim of cardiomyoplasty is to prol ong survival and to improve the quality of life of patients with sever e chronic and irreversible myocardial failure by improving systolic co ntraction and correcting diastolic dysfunction. Methods: To evaluate t he long-term outcome of cardiomyoplasty, we investigated 82 patients e lectively undergoing this procedure in our hospital. All patients had severe chronic heart failure that did not respond to optimal medical t reatment, Patients had a mean age of 50 +/- 12 years (84% males), The cause of heart failure was ischemic (55%), idiopathic cardiomyopathy ( 34%), ventricular tumor (6%), and other (5%). The mean follow-up was 4 .3 years. Results: The mean New York Heart Association functional clas s improved after operation from 3.2 to 1.8. Average radioisotopic left ventricular ejection fraction increased from 17% +/- 6% to 28% +/- 3% (p < 0.05). Stroke volume index increased from 35 +/- 9 to 46 +/- 8 m l/beat/m(2) (p < 0.05). The heart size remained stable at long term (e valuated by echo and computed tomography scanning). After cardiomyopla sty the number of successive hospitalizations resulting from congestiv e heart failure was reduced to 0.4 hospitalizations/patient/year (befo re operation 2.5, p < 0.05). Computed tomography scans showed at long- term a preserved LDM structure in 82% of patients who underwent operat ion. Survival probability at 7 years was 54% for the totality of patie nts, and 66% for patients who underwent operation in New York Heart As sociation functional class 3. Five patients underwent heart transplant ation after cardiomyoplasty (mean delay 29 months), principally as a r esult of the natural evolution of their underlying heart disease, with out major technical difficulties, Conclusions: Our 10-year clinical ex perience demonstrates that cardiomyoplasty increases ejection fraction , improves functional class, and ameliorates quality of life. Ventricu lar volumes and diameters remain stable long term. LDM structure is ma intained long term if electrostimulation is performed avoiding excessi ve myostimulation. Patient selection is the most important determinant for early and late outcome. Late death in patients undergoing cardiom yoplasty is principally due to sudden death. Our future aim is to inco rporate a cardioverter-defibrillator in the cardiomyostimulator, thus improving long-term results. Cardiomyoplasty may delay or prevent end- stage heart failure and the need for heart transplantation.