Long-term study of the ultrastructural changes of myocardium in patients undergoing cardiac surgery, with more than 10 years follow-up

Abstract The myocardium from 44 patients undergoing open cardiac surgery was studied to determine if alterations demonstrable with the electron microscope could be related to prognosis. Planimetric methods were used to evaluate myofibrils, Golgi, mitochondria, myelin figures, other organelles, and intracellular space in order to achieve as objective a measurement as possible. Morphologic changes were graded and correlated with clinical findings and results after long-term follow-up. Factors evaluated in terms of survival included patient age, degree and extent of valvular disease, the presence of coronary artery disease, and degenerative changes of the myocardium as demonstrated ultrastructurally. Patients dying, of cardiac causes, within the first 5 years, had a higher ultrastructural grade than those surviving for more than 10 years. Statistical analysis, using stepwise regression methods, demonstrated a highly significant correlation ( P P P Ultrastructural changes, in our study, provided the single best predictor of survival, and age of the patient, as an added variable, is the second best predictor.