Increased Premature Ventricular Contraction Burden During Exercise Stress Testing with Surgical Face Masks: A Retrospective Cohort Study

Introduction: The physiological impact of surgical face masks on exercise-induced arrhythmias remains poorly understood. This study aimed to evaluate changes in premature ventricular contraction (PVC) burden during exercise stress testing performed with and without surgical masks.Methods: We retrospectively analyzed 41 patients who underwent exercise ECG stress testing with and without face mask. Inclusion criteria included age 18–75 years, treadmill exercise with ≥85% maximum predicted heart rate, and absence of ischemia or significant arrhythmias. PVC burden was calculated as the ratio of PVC beats to total beats during exercise. Paired t-tests compared PVC burden with and without masks.Results: PVC burden was significantly higher during masked testing (0.91% ± 0.38) compared to unmasked testing (0.52% ± 0.25) (p < 0.001). Seventy-one percent of patients demonstrated increased PVC burden with masks, and 44% exhibited increases greater than 0.3%, potentially clinically relevant. No sustained arrhythmias or test terminations occurred.Discussion and conclusion: Surgical face mask use during exercise stress testing is associated with increased PVC burden, likely due to mild hypoxia or autonomic stress. Awareness of this effect is important for interpretation of exercise-induced arrhythmias during masked testing. Further prospective studies incorporating oxygen saturation and autonomic monitoring are warranted.