Quantitative computed tomography assessment of right ventricular remodeling after right ventricular outflow tract reconstruction using a conduit in patients with pulmonary atresia and ventricular septal defect: Correlations with echocardiographic parameters.

BACKGROUND

This retrospective study aimed to assess computed tomography (CT)-derived quantitative right ventricular (RV) remodeling patterns after RV outflow tract reconstruction using a conduit in patients with pulmonary atresia and ventricular septal defect and correlate them with echocardiographic parameters.

METHODS

A total of 61 patients (90 CT volumetry studies, age: 16.2 ​± ​6.5 years) were retrospectively evaluated. Ventricular volume, myocardial mass, ejection fraction, stroke volume (SV), and SV difference were compared between the valveless and valved conduit groups; they were analyzed according to echocardiography-derived RV outflow tract pressure gradient and RV systolic pressure.

RESULTS

The valveless conduit group had smaller indexed left ventricular (LV) end-diastolic volume (83.4 ​± ​14.9 ​mL/m2 [mean ​± ​standard deviation] vs. 90.6 ​± ​17.6 ​mL/m2; p ​< ​0.039) and indexed LV SV (43.0 ​± ​8.0 ​mL/m2 vs. 48.0 ​± ​8.9 ​mL/m2; p ​< ​0.006), larger indexed RV end-diastolic volume (118.0 ​± ​26.1 ​mL/m2 vs. 98.1 [84.6-114.2] mL/m2 [median {interquartile range}]; p ​= ​0.010), indexed RV SV (62.5 ​± ​13.8 ​mL/m2 vs. 49.3 ​± ​13.7 ​mL/m2; p ​< ​0.001), and indexed SV difference (19.5 ​± ​12.3 ​mL/m2 vs. -2.2 [-6.5-4.8] mL/m2; p ​< ​0.001), and higher RV ejection fraction (53.2 ​± ​7.9 ​% vs. 48.7 [42.5-54.8]%; p ​= ​0.018) than the valved conduit group. The moderate or severe pulmonary stenosis group had higher indexed RV myocardial mass (54.03 ​± ​15.1 ​g/m2 vs. 43.8 [34.4-52.2] g/m2; p ​= ​0.012); the moderately or severely elevated RV systolic pressure group had smaller indexed RV SV (53.4 ​± ​16.5 ​mL/m2 vs. 62.8 ​± ​15.1 ​mL/m2; p ​< ​0.032) and indexed SV difference (7.0 ​± ​14.7 ​mL/m2 vs. 18.8 ​± ​14.7 ​mL/m2; p ​< ​0.005) and larger indexed RV myocardial mass (58.2 [47.4-63.1] g/m2 vs. 46.0 ​± ​12.9 ​g/m2; p ​= ​0.013).

CONCLUSION

Cardiac CT can be used to quantitatively evaluate RV remodeling after RV outflow tract reconstruction using a conduit patterns in patients with pulmonary atresia and ventricular septal defect. Echocardiography-derived pulmonary stenosis and elevated RV systolic pressure demonstrate significant correlations with the CT-derived parameters.