Serial Cardiopulmonary Exercise Testing in Patients after Extracardiac Conduit Total Cavopulmonary Connection for Single-Ventricle Hearts: An Observational Study

Abstract

Objective: To analyze the aerobic fitness and evolution of exercise tolerance in patients with single-ventricle physiology after total cavopulmonary connection (TCPC) with an extracardiac conduit (ECC).

Study design: This retrospective cohort study included patients with previous ECC-TCPC who underwent cardiopulmonary exercise testing (CPET) between September 2010 and September 2019. Patients who completed at least 2 tests (≥6 months apart) with adequate levels of effort were recruited for the serial CPET evaluation.

Results: We identified 70 patients (50% male) with a mean age of 6.45 ± 5.14 years at ECC-TCPC and 15.67 ± 5.03 years at the initial CPET. The peak oxygen consumption (peak VO₂) to predicted value (peak PD) was 55.90 ± 16.81%. Twenty of the 70 identified patients (50% male) were recruited for serial analysis. The average number of CPETs was 2.6 per patient. The average duration from the first CPET to the last CPET was 3.64 years. The peak VO₂ and PD increased slowly, with mean rates of 38.77 ± 129.01 mL/min and 1.66 ± 6.40%, respectively, during the study period.

Conclusions: Although the patients had lower exercise tolerance after ECC-TCPC compared with their normal peers, exercise tolerance appears to have been preserved over the adolescent period in those who underwent serial testing after ECC-TCPC.

Keywords: Fontan; cardiopulmonary exercise testing; extracardiac conduit; single ventricle; total cavopulmonary connection.