Symptoms during ATP-test under pacing: impact on syncope recurrence and prediction from the ATP-test without pacing

Syncope recurrence in patients with positive ATP-test who underwent permanent pacemaker implantation is suspected to be related to vagal vasodilatation. We studied symptoms during ATP-test in 38 temporary paced patients. Among patients with positive ATP-test who underwent permanent pacemaker implantation (N = 14), the only one patient who recurred during follow-up was symptomatic during the initial paced ATP-test. Symptoms during paced ATP-test were well predicted by a higher blood pressure (BP) drop during standard ATP-test (i.e. without pacing) (Area under ROC curves > 0.70 for all BP parameters except for relative diastolic BP drop). Moreover, BP drop during standard and paced ATP-test were significantly correlated (all p ≤ 0.03). Thus, a higher BP drop measured during ATP-test without pacing might help identify patients who would experience recurrences due to vasodilatation under permanent pacing.