Literature review and pilot studies of the effect of QT correction formulas on reported beta2-agonist-induced QTc prolongation.

Background: Drugs that stimulate the beta2-adrenergic receptor have been reported to prolong the QT interval corrected for heart rate (QTc interval), a potential mechanism for cardiac toxicity.

Objective: This study evaluated whether beta2-adrenergic agonist drugs prolong the QTc interval when different correction formulas for the effect of heart rate are used.

Methods: Healthy subjects of both sexes aged 19 to 33 years were recruited with advertisements.

Congenital episodic hypertension.

We report two patients who have congenital episodic severe hypertension and dysautonomic symptoms. Their hypertensive episodes were successfully treated with antiadrenergic and antihypertensive agents. Their clinical course improved with intermittent treatment of their episodes of severe hypertension.