ABSTRACT
BACKGROUND: We investigated whether hemodynamics changes during head-up tilt test (HUT) predict the efficacy of preventive drugs in neurally mediated syncope (NMS) patients, in order to clarify the differences between drug responders and nonresponders. METHOD: In 402 patients with syncope, we examined HUT. In 66 patients with induced NMS, we administered propranolol when heart rate (HR) > 60 and systolic blood pressure (SBP) > 100 mmHg. When HR