A possible role for autoantibodies in left ventricular hypertrophy.

The purpose of the study was to investigate the possible role of autoantibodies in the development and type of left-ventricular hypertrophy (LVH). Three groups of subjects were studied: (a) 15 patients with hypertrophic cardiomyopathy (HCM; 11 males, 4 females; mean age 50.0 +/- 16.3 years); (b) 15 patients with essential hypertension (10 males, 5 females; mean age 56.8 +/- 13.5 years) with normal renal function and serum electrolytes and (c) 15 male athletes (mean age 20.8 +/- 5.9 years). The control group consisted of 15 normal subjects with no sign of heart disease. The following indices of cardiac performance were determined by means of echocardiography: end-diastolic and end-systolic diameters, interventricular septum thickness, left-ventricular (LV) wall thickness, LV mass and LV mass index. The immunologic parameters studied included autoantibodies against (a) specific (anticardiac cell; ACA) and (b) nonspecific (antimitochondrial cell; AMA) autoantigens according to a conventional indirect immunofluorescence technique. (1) Higher values for LV mass and LV mass index were observed in HCM. (2) The incidence of specific and non-specific autoantibodies in hypertensive patients and in patients with HCM was significantly higher compared to athletes and controls. All ACA-positive individuals (5 with HCM, 3 with hypertension and 1 athlete) were AMA positive as well, while all ACA-negative individuals were also AMA negative. The ACA-positive individuals had higher C3c and C4 levels compared to the ACA-negative individuals. An autoantibody-mediated immunopathogenic role is discussed in the development and type of myocardial hypertrophy.