CYTOMETRIC ANALYSIS OF VENTRICULAR MYOCYTE NUCLEI IN IDIOPATHIC DILATED CARDIOMYOPATHY - A TOOL FOR EVALUATION OF DISEASE PROGRESSION

The progression of idiopathic dilated cardiomyopathy (IDC) is governed by factors that remain obscure. The disease pathway toward cell degen eration or death results in irreversible myocyte change including nucl ear cytometric alterations which may be evaluable and ultimately corre lated with other measures of disease evolution. Using a novel image cy tometry system, we analysed differences in ventricular myocyte nuclear morphology and DNA content and distribution in right and left ventric ular free wall myocardium and in ventricular septal myocardium from II normal and 13 IDC human autopsy hearts. Nine morphological features o f IDC myocyte nuclei differed significantly (P < 0.001) front normal. These were used to establish a classification matrix and cytometry-bas ed assessment and allowed correct categorization of left and right ven tricular and ventricular septal myocyte nuclei in concordance with the ir respective pathological diagnosis (i.e. normal oi IDC) 71%, 81% and 77% of the time. Additionally, four photometric features were signifi cantly different (P < 0.005) in IDC versus normal hearts as were three discrete texture features (P < 0.001). Thus the spectrum of myocyte n uclei seen in IDC have highly characteristic and measurable morphologi c, photometric and texture features Our findings indicate the potentia l value of cytometry in the classification of myocytes with regards to a disease continuum and suggest its applicability in both clinical an d experimental studies.