Histological and immunohistochemical changes of the myocardium in dilated cardiomyopathy

Abstract

Dilated cardiomyopathy is a major cause of heart failure and a major cause of morbidity and mortality. It is a multifactorial disease that includes both hereditary and acquired forms. It is estimated that around 20-35% of patients with dilated cardiomyopathy have hereditary forms. It is the third most common cause of heart failure and the most common cause of heart transplant. Dilated cardiomyopathy can be a secondary condition of many diseases such as coronary heart disease, diabetes, pheochromocytoma, infections, malnutrition, ingestion of toxic substances (alcohol, cocaine), ingestion of chemotherapeutic drugs, autoimmune diseases. In our study, we aimed to describe the changes of myocardial cells and interstitial connective tissue in patients clinically diagnosed with alcoholic dilated cardiomyopathy. The material studied consisted of heart fragments sampled from the left ventricle (LV) during necropsy from a total of 28 patients, aged between 58 and 73 years, with a clinical and laboratory diagnosis of dilated cardiomyopathy, hospitalized in the Cardiology Center of the Emergency County Hospital of Craiova in 2009 and 2010. In dilated cardiomyopathy, myocardial muscle fibers appeared slightly elongated or wavy, with hypochromatic, heterogeneous, vacuolar sarcoplasm, by a decrease of myofibril numbers. Lipofuscin granules were frequently seen in the sarcoplasm. Nuclear changes were consistent with sarcoplasmic alterations. Changes of the interstitial connective tissue were sometimes extensive and sometimes barely noticeable. The most common alteration of this structure was the onset and development of a mainly perivascular collagen fibrillogenetic process.