The diagnostic value of including an exercise session during 24-h ambulatory ECG monitoring in athletes

Introduction: In athletes undergoing pre-participation screening (PPS), ambulatory ECG monitoring is often prescribed in cases of arrhythmias at baseline or suspicious symptoms. Since performing an exercise session during 12‑leads 24-h ambulatory ECG monitoring (24 h-ECG) is recommended but not supported by evidence, this study aimed to evaluate whether the inclusion of exercise sessions enhances the detection of high-risk cardiovascular diseases (CVD). Methods: This study analysed 4315 athletes who underwent PPS with exercise stress testing (EST) at our centre and who, due to abnormal findings, were referred for second-line investigations, including 24 h-ECG with an exercise session. Athletes were categorised according to the presence and exercise-relation of premature ventricular beats (PVBs) on 24 h-ECG. Third-line assessments were prescribed in selected cases. Results: 235 athletes were included in the study: 154 (66 %) athletes showed <10 PVBs, 22 exercise-suppressed PVBs, 23 with PVBs that occurred during both rest and exercise, 36 exercise-induced PVBs. 13 athletes were identified with high-risk CVD: 4/176 (2.3 %) among those with no or exercise-suppressed PVBs versus 9/59 (15 %, p < 0.001) among those with exercise-persistent or exercise-induced PVBs. Among the 26 athletes with PVBs during both peak exercise on EST and 24 h-ECG, 7 (27 %) were diagnosed with high-risk CVD, compared to 6 (2.9 %, p < 0.001) of the remaining 209 athletes. Conclusions: Incorporating an exercise session into 24 h-ECG improves the detection of arrhythmic patterns potentially associated with high-risk CVD. The risk was particularly high when exercise-induced PVBs were observed during both EST and 24 h-ECG. These findings support the implementation of exercise-inclusive 24 h-ECG protocols in sports cardiology.