Abstract 15379: Syncope and Pre-Syncope on the Exercise Test

Abstract

Background: Data on the occurrence of syncope and presyncope with hemodynamic instability during graded exercise test (GXT) are limited. Methods: We reviewed the Mayo Integrated Stress Center database for non-imaging GXTs performed between January 2006 and December 2010 and registered syncopic/presyncopic episodes. Electronic medical records were reviewed for clinical information, outcomes, and mortality. SAS was used to provide background statistics. Results: During the study period, a total of 40,715 GXTs were performed on 33,885 unique patients, including 16,306 (40.0%) GXTs on patients with known cardiovascular disease (CVD). High risk for cardiac syncope is defined as prior cardiac arrest/ventricular tachycardia, ischemic cardiomyopathy, implanted defibrillator, history of atrial fibrillation, sotalol, amiodarone, LQTS, HOCM, aortic stenosis was identified in 3263 patients (6.0%), while risk factors for non-cardiac syncope (POTS, history of dizziness/spells/syncope, rest SBP < 100 mmHg, age ≥ 80 years, female age < 30 years, beta blocker use) were found in 15,925 patients (39.1%). Despite the presence of so many patients at risk, only 8 episodes of syncope occurred (0.020% per test; 0.023% per individual patient). Another 5 episodes of near-syncope with documented hypotension were aborted by the quick action of the testing staff (0.012% per test; 0.015% per individual patient). Only 1 patient (a 71yo M with severeCAD) required electrical cardioversion for ventricular fibrillation. None of the other patients, including all 6 women, presented with tachyarrhythmias. There were no deaths and no significant musculoskeletal trauma. Conclusion: Despite many patients with risk factors for cardiac and non-cardiac syncope in the cohort, syncope, and near-syncope with hemodynamic instability were very rare findings on guideline-directed GXTs.