A Prospective Placebo Controlled Randomized Study of Caffeine in Patients with Supraventricular Tachycardia Undergoing Electrophysiologic Testing

Study of Caffeine in Patients with Supraventricular TachycardiaIntroduction Patients with cardiac arrhythmias are generally instructed to avoid caffeine intake. A comprehensive evaluation of the electrophysiological effects of caffeine on atrial and ventricular tissues in humans has not previously been performed. Methods and Results Eighty patients (31 men, mean age 49 ± 14 years) with symptomatic supraventricular tachycardia (SVT) undergoing an electrophysiologic study (EPS) prior to catheter ablation were randomized to receive oral caffeine or placebo. Caffeine at a dosage of 5 mg/kg (moderate intake) or placebo tablets were administered orally at a mean time of 57 ± 13 minutes prior to the EPS. The median (IQR) caffeine level in patients receiving caffeine was 7.4 μg/mL (4.7–8.7), as compared with 0.15 (0.00–0.61) in patients receiving placebo, P