Effect of shunt type on echocardiographic indices after initial palliations for hypoplastic left heart syndrome: Blalock-Taussig shunt versus right ventricle-pulmonary artery conduit.
OBJECTIVE
The study objective was to compare echocardiographic indices in infants with hypoplastic left heart syndrome (HLHS) randomized to different surgical pathways.


BACKGROUND
Initial surgical palliation for HLHS has evolved to two strategies that vary by source of pulmonary blood flow: a modified Blalock-Taussig (BT) shunt or a right ventricle to pulmonary artery (RV-PA) conduit.


METHODS
Seventeen patients were randomized to either a BT shunt or RV-PA as their first-stage palliation, and 15 survived through bidirectional Glenn (BDG) (seven BT shunts/eight RV-PAs). Echocardiography was performed pre-stage 1 palliation (S1P), early post-S1P, pre-BDG, and post-BDG. Echocardiographic measurements included indices of right ventricle function and shape, right ventricle myocardial performance index, neoaortic Doppler flow patterns and cardiac output, Doppler inflow and tissue imaging, and conduit/neoaortic regurgitant fraction.


RESULTS
There were no significant differences in right ventricle size, shape, or estimates of systolic and diastolic function between groups. Patterns of changes in neoaortic Doppler flow in the RV-PA conduit group showed a decrease in all indices of systemic flow early after initial palliation, but these measures consistently increase later post-S1P and post-BDG. In contrast, the BT shunt group increases these same indices post-S1P and pre-BDG with a decrease after shunt removal.


CONCLUSIONS
Right ventricle size and function do not appear significantly affected by surgical type of initial palliation for HLHS, and this correlates with early outcome. Echocardiographic Doppler findings correlate well with the expected physiologies of the different shunts as these infants progress through initial palliative strategies.
Frommelt
Peter C
PC
Division of Pediatric Cardiology, Department of Pediatrics, Medical College of Wisconsin, Milwaukee, Wisconsin, USA. pfrom@mcw.edu
Sheridan
David C
DC
Mussatto
Kathy A
KA
Hoffman
George M
GM
Ghanayem
Nancy S
NS
Frommelt
Michele A
MA
Tweddell
James S
JS
D000714:Anastomosis, Surgical / Q000379:methods*; D004452:Echocardiography / Q000379:methods*; D005260:Female; D006352:Heart Ventricles / Q000601:surgery*; D006801:Humans; D018636:Hypoplastic Left Heart Syndrome / Q000000981:diagnostic imaging* / Q000601:surgery*; D007231:Infant, Newborn; D008297:Male; D010166:Palliative Care / Q000379:methods*; D011379:Prognosis; D011651:Pulmonary Artery / Q000601:surgery*; D016896:Treatment Outcome