Impaired peripheral vasoconstriction in response to alpha-adrenergic stimulation in patients with idiopathic hypertrophic cardiomyopathy

摘要: Exercise hypotension has been documented in patients with hypertrophic cardiomyopathy (HCM). Some investigators reported that this is due to an inadequate increase of systemic vascular resistance during or after exercise. The aim study was investigate the pathogenesis limb response abnormalities idiopathic HCM. Thirteen HCM and 9 healthy controls were administered endothelium-dependent dilator (acetylcholine), a direct smooth muscle (nitroglycerin), alpha-adrenergic stimulator (phenylephrine), beta-adrenergic (isoproterenol) by intra-arterial infusion. Peripheral assessed forearm plethysmography at rest each infusion obtain percentage change resistance. Isoproterenol, acetylcholine nitroglycerin produced dose-related vasodilatation no significant differences between controls. significantly less than phenylephrine infusions 0.5μg/min (155±38% vs 195±47%, mean ± SD, p<0.05) 1.0μg/min (174±49% 238 65%, p<0.05). Vasoconstriction mediated receptors appeared be impaired peripheral vasculature (Jpn Circ J 1998; 62: 903 - 908)