Myocytes’ apoptosis and proliferation in endomyocardial biopsy as prognostic factors in terminal heart failure

Abstract

The aim of the preliminary study was to evaluate the role of apoptosis and proliferation of myocytes in order to predict the prognosis and optimal treatment of patients with end-stage dilated cardiomyopathy. Endomyocardial biopsy was performed during open-heart surgery (reductive annuloplasty of double orifice) in 19 patients with end-stage dilated cardiomyopathy. The terminal deoxynucleotidyl transferase d-UTP-biotin nick-end labelling (TUNEL) method was used for the detection of apoptosis, and immunohistochemical methods were used for the evaluation of inhibitor of apoptosis such as proto-oncogene Bcl-2 (B-cell lymphoma gene), and proliferative markers such as proliferation cell nuclear antigen (PCNA) and Ki-67 proliferative antigen. The increased percentage of apoptotic myocytes and decreased expression of bcl-2 is associated with earlier death after surgery. Increased expression of proliferation markers of myocytes in patients who survived seven years after surgery compared to those who died within three years suggest that adult cardiomyocytes are not terminally differentiated and this might represent potential growth reserve of the diseased heart. Based on our preliminary study we may conclude that myocytes’ apoptosis and proliferative activity might help us to predict the prognosis and optimal treatment of patients with end-stage dilated cardiomyopathy.