Ischemic versus idiopathic cardiomyopathy: differing neurohumoral profiles despite comparable peak oxygen uptake

Objective: We tested the hypothesis that neurohormonal and immunological activation differs in ischemic and idiopathic dilated cardiomyopathy since recent intervention trials indicate that ischemic cardiomyopathy seems to carry a worse prognosis than idiopathic cardiomyopathy of comparable clinical severity. Methods: In ten patients with ischemic cardiomyopathy undergoing spiroergometric evaluation venous levels of norepinephrine, epinephrine, renin, angiotensin, atrial natriuretic peptide as well as soluble interleukin-2-receptor were determined before, during and 10 min after exercise. Results were compared to sixteen patients with idiopathic cardiomyopathy with similar peak oxygen uptake (13.3±3 vs. 13.6±3 ml/kg/min; P=ns). Results: In ischemic patients, norepinephrine, angiotensin, and interleukin-2 receptor levels were significantly higher before, during and after exercise. Interleukin-2-receptor levels correlated with angiotensin. Conclusions: We conclude that in ischemic as compared to idiopathic cardiomyopathy, a more pronounced activation of the sympathetic, renin–angiotensin and T-cell immune system is present at rest, during and after exercise. These data may contribute to explain differences in response to intervention and in prognosis. They warrant further investigation.