Heart rate and plasma cyclic AMP responses to isoproterenol infusion and effect of beta-adrenergic blockade in patients with postural orthostatic tachycardia syndrome.


To clarify the pathophysiological mechanism of postural orthostatic tachycardia syndrome (POTS). the responses of heart rate and the plasma cyclic AMP (cAMP) level to isoproterenol infusion in the supine position were evaluated in 10 POTS patients and 10 age-matched controls. Also, the effect of beta-adrenergic blockade on POTS was assessed using the headup… (More)