Quantitative analysis of the distribution of cardiac muscle cell disorganization in the left ventricular wall of patients with hypertrophic cardiomyopathy.

Abstract

The distribution of cardiac muscle cell disorganization in different regions of the left ventricular wall was studied quantitatively in 52 patients with hypertrophic cardiomyopathy. Cellular disorganiza- tion in the ventricular septum was both common and extensive (mean area of septal tissue section disorganized, 35 i 4%). Disorganization was also substantial (24 3%) in the left ventricular free wall of these patients, although less marked than in the ventricular septum (p < 0.05). Anterior left ventricular free wall disorganization was particularly extensive (32 4%) and did not differ significantly from that present in the ven- tricular septum. Marked cardiac muscle cell disorganization (> 5% of the tissue section) was diffusely dis- tributed in the ventricular septum and left ventricular free wall in 33 of the 52 patients (63%).