The impact of tricuspid valve regurgitation severity on exercise capacity and cardiac-related hospitalisations among adults with non-operated Ebstein's anomaly.

BACKGROUND

Tricuspid valve regurgitation is an inherent part of Ebstein's anomaly, yet whether the severity of the regurgitation further impairs exercise capacity and contributes to long-term morbidity on top of the lesion severity per se is unknown.

METHODS

To evaluate for this potential effect, we included 30 patients with Ebstein's anomaly who did not undergo any form of surgical interventions and had a cardiopulmonary exercise test and echocardiographic studies in this retrospective analysis. Echocardiographic studies and cardiopulmonary exercise tests were critically reviewed for lesion severity grade, tricuspid regurgitation degree, and exercise parameters. Cardiac-related hospitalisations were recorded from computerised medical records and during clinic visits.

RESULTS

Fourteen patients (47%) had moderate and 8 (27%) had severe regurgitation. Patients with ≥ moderate regurgitation exhibited significantly lower exercise capacity (median % predicted maximal oxygen consumption, 62 versus 79%, p = 0.03) and venilatory efficiency at exercise. When stratifying exercise results by regurgitation degree, a stepwise decrease in oxygen consumption and ventilatory efficiency with increasing regurgitation severity was observed, regardless of the anatomic lesion severity. During a median follow-up of 4.6 years, > moderate tricuspid regurgitation was associated with significantly lower cumulative probability of freedom from cardiac hospitalisations.

CONCLUSIONS

We report that among non-operated Ebstein's anomaly patients, greater tricuspid regurgitation severity was associated with worse exercise capacity and with overall higher probability of cardiac-related hospitalisations independent from the underlying lesion severity.