Shenthar J, et al. - In this prospective study, researchers examined patients with structural heart disease (SHD) and negative electrophysiology study (EPS) results to identify the cause of recurrent syncope and clinical outcomes using the head-up tilt test and an insertable loop recorder. Overall, 41 SHD patients with 27 cases of coronary arterial disease and 14 of dilated cardiomyopathy with mean EF of 42 ± 4.8% (range 30% to 49%) were analyzed. They identified reflex syncope as the most commonly seen cause of syncope. In patients with SHD, negative EPS results, left ventricular systolic dysfunction with left ventricular EF >30%, reflex syncope caused nearly 60% of cases, though not in heart failure.