Multicenter Study Comparing Shunt Type in the Norwood Procedure for Single-Ventricle Lesions

Abstract

Background The Pediatric Heart Network’s (PHN) Single Ventricle Reconstruction Trial (SVR) randomized infants with single right ventricles (RV) undergoing a Norwood procedure to a modified Blalock-Taussig or RV-to-pulmonary artery shunt. This report compares RV parameters in the two groups using 3-dimensional echocardiography (3DE). Methods and Results 3DE studies were obtained at 10/15 SVR centers. Of the 549 subjects, 314 underwent 3DE studies at one to four time points (pre-Norwood, post-Norwood, pre-stage II, and 14 months) for a total of 757 3DEs. Of these, 565 (75%) were acceptable for analysis. RV volume, mass, mass:volume ratio, ejection fraction (EF), and severity of tricuspid regurgitation did not differ by shunt type. RV volumes and mass did not change after the Norwood, but increased from pre-Norwood to pre-stage II (end-diastolic volume [EDV, ml]/body surface area [BSA]1.3, end-systolic volume [ESV, ml]/BSA1.3 and mass[g]/BSA1.3 mean difference [95% confidence interval] = 25.0 [8.7, 41.3], 19.3 [8.3, 30.4], and 17.9 [7.3, 28.5], then decreased by 14 months (EDV/BSA1.3, ESV/BSA1.3 and mass/BSA1.3 mean difference [95% confidence interval] = −24.4 [−35.0, −13.7], −9.8 [−17.9, −1.7], and −15.3 [−22.0, −8.6]. EF decreased from pre-Norwood to pre-stage II (mean difference [95% confidence interval] = −3.7% [−6.9%, −0.5%]), but did not decrease further by 14 months. Conclusions We found no statistically significant differences between study groups in 3DE measures of RV size and function, or magnitude of tricuspid regurgitation. Volume unloading was seen after stage II, as expected, but EF did not improve. This study provides insights into the remodeling of the operated univentricular RV in infancy. Clinical Trial Registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT00115934.

Interstage evaluation of homograft-valved right ventricle to pulmonary artery conduits for palliation of hypoplastic left heart syndrome

“…27 Using both 2-and 3-dimensional echocardiography, those investigators showed no differences in RV function or the prevalence of significant TR between those undergoing mBTS and RV-PA conduit during the interstage period and up to age 14 months. 27,28 Considering the lack of a measurable difference between patients with those vastly different shunt physiologies, it is not surprising that we did not observe a difference between the VC and NVC groups.…”

Simultaneous Volumetric and Functional Assessment of the Right Ventricle in Hypoplastic Left Heart Syndrome After Fontan Palliation, Utilizing 3-Dimensional Speckle-Tracking Echocardiography

“…Although quantitative assessment of RV function in HLHS by echocardiography is challenging, 3DE assessment of volumes and EF has been verified as a comparable method with CMRI even in HLHS patients and used in a multicenter clinical study. 7 In our study, we compared the RV volumes obtained with3D-STE with those from 3DE in HLHS patients after Fontan palliation, showing excellent correlations between them. From these results, we suggest that 3D-STE is as useful as 3DE for volume measurement in HLHS patients after Fontan palliation.…”

“…On the other hand, 3D echocardiography (3DE) has been shown to be a possible alternative for measuring RV volume in HLHS. [6][7][8][9] Additionally, 2D speckle-tracking echocardiography (STE) has been recognized as a useful method for assessing not only ventricular function but also the mechanics of ventricular function in HLHS. 10, 11 More recently, the advent of 3D-STE has allowed us to measure the 3D ventricular volumes and strains simultaneously in the left ventricle (LV).…”

Association Between Digoxin Use and Cardiac Function in Infants With Single-Ventricle Congenital Heart Disease During the Interstage Period

“…Several studies have previously confirmed this impairment of RV function and unfavorable change in RV size after S1P. A pair of secondary analyses of the SVR trial comparing indices between S1P surgical shunt types showed an increased BSA-indexed RV end-systolic volume, lower RV ejection fraction, and lower RV fractional area change from the post-S1P to pre-S2P echocardiogram (13, 19). Our findings confirm this but also demonstrate that digoxin may stabilize the fragile hemodynamics and lessen the expected RV dysfunction and dilatation seen during the interstage period.…”