Anorexia and the heart. Results of studies to assess effects.

Patients with anorexia nervosa have a small heart on the chest x-ray, with a reduction in myocardial mass. Anorectic patients who have normal electrolyte values do not have a significant incidence of ventricular ectopy at rest or with exercise, and they maintain sinus rhythm, although ECGs of adolescent females are abnormal. Our patients had a reduction of their total body weight, percent fat, and fat-free (lean) body mass, as well as a significant reduction in myocardial mass. Heart rate and blood pressure response to exercise were blunted, and oxygen consumption and total work performance were reduced. Hemodynamic studies generally showed a lowered cardiac index, most likely secondary to the small size of the heart and the reduction in stroke volume. In addition, preliminary data suggest that diastolic compliance is abnormal in these patients. Long-term follow-up of the cardiovascular status of all patients with anorexia nervosa patients is necessary to see if cardiac abnormalities demonstrated before treatment disappear after weight gain and resumption of normal activities. Cardiac function should be carefully evaluated, because the reduced exercise performance in these patients may be secondary to cardiac dysfunction as well as to the loss of peripheral muscle mass. Bulimic patients also need to be watched closely, particularly those whose potassium level is less than 3 mEq.