Is there autonomic impairment in congestive (dilated) cardiomyopathy?

Autonomic function was investigated in patients with congestive (dilated) cardiomyopathy and compared with that in controls. Heart-rate and blood-pressure were recorded during physiological and pharmacological interventions and plasma noradrenaline concentration was measured at rest and when the physiological interventions produced a peak response. The results indicate that even at an early (pre-failure) stage of the disease parasympathetic function is impaired but no significant increase in sympathetic activity occurs at this stage.