Norwood operation versus comprehensive stage II after bilateral pulmonary artery banding palliation for infants with critical left heart obstruction

Norwood Operation with Right Ventricular-Pulmonary Artery Shunt Versus Comprehensive Stage II After Bilateral Pulmonary Artery Banding Palliation

As a strategy for the primary Norwood operation, the right ventricular-pulmonary artery shunt is associated with satisfactory early outcome. However, use of this shunt after bilateral pulmonary artery banding remains controversial. This study compared the operative outcomes and late hemodynamics in patients who underwent the Norwood operation, preceded by bilateral pulmonary artery banding, with a right ventricular-pulmonary artery shunt or with bidirectional Glenn anastomosis (comprehensive stage II strategy). We retrospectively reviewed 38 patients who underwent the Norwood operation preceded by bilateral pulmonary artery banding between 2004 and 2017. Of these, 17 underwent the Norwood operation with a right ventricular-pulmonary artery shunt (Group S), whereas 21 underwent the comprehensive stage II strategy (Group G). 5 years after the Norwood operation, 10 (60%) and 17 (81%) patients in Group S and Group G, respectively, underwent the Fontan procedure. Group S showed significantly lower pressure in the superior vena cava after bidirectional Glenn anastomosis than Group G (13 ± 2 mmHg vs. 18 ± 3 mmHg; p < 0.01), but pressures were similar after the Fontan procedure. The right ventricular end-diastolic volume at 1 year post-Fontan procedure was significantly higher in Group S than in Group G (142 ± 41% vs. 91 ± 28%; p < 0.01). In terms of early outcomes, the Norwood operation with a right ventricular-pulmonary artery shunt enabled low pressure in the superior vena cava, but in the long term, this shunt adversely influenced the right ventricular volume.

Long-term outcomes of hypoplastic left heart syndrome with analysis of the Norwood procedure in infants following bilateral pulmonary artery banding

Objective

To investigate the early and long-term outcomes of the deferred Norwood procedure by bilateral pulmonary artery banding (BPAB) versus the neonatal Norwood procedure.

Methods

This retrospective study examined 46 patients with hypoplastic left heart syndrome and its variants undergoing the Norwood procedure for single ventricle physiology between 2004 and 2022 at 3 institutions. The patients were divided into 2 groups: neonatal Norwood procedure (group N; n = 23) and staged Norwood procedure in infants following BPAB (group I; n = 23). Preoperative risk factors, surgical results, survival rates, Fontan candidacy, and long-term complications were compared.

Results

Early survival rates after the Norwood procedure were 91.3% (21 of 23) in both groups. Late survival rates after the Norwood procedure were similar at the 10-year follow-up (group N, 76.3%; group I, 68.7%; P = .63). Fontan completion rates also were comparable in the 2 groups (group N, 77.8%; group I, 85.7%; P = .67). Group N showed a higher median pulmonary artery (PA) index before bidirectional cavopulmonary connection (group N, 177 [interquartile range (IQR), 147-243] mm2/m2; group I, 152 [IQR, 146-163] mm2/m2; P = .03); this trend continued until 5 years after Fontan completion (P = .01). Group N also had a lower rate of freedom from protein-losing enteropathy (PLE) at 9.0 years after the Fontan operation (90.0% vs 52.5% for group I; P = .04), although the incidences of other Fontan-associated events were not significantly different.

Conclusions

Fontan candidacy and survival rates were similar regardless of the timing of the Norwood procedure. Early performance of the Norwood procedure may lead to lower rates of late Fontan-associated events, such as PLE.

Hybrid palliation versus nonhybrid management for a multi-institutional cohort of infants with critical left heart obstruction

OBJECTIVE

To compare patient characteristics and overall survival for infants with critical left heart obstruction after hybrid palliation (bilateral pulmonary artery banding with or without ductal stenting) versus nonhybrid management (eg, Norwood, primary transplantation, biventricular repair, or transcatheter/surgical aortic valvotomy).

METHODS

From 2005 to 2019, 1045 infants in the Congenital Heart Surgeons' Society critical left heart obstruction cohort underwent interventions across 28 institutions. Using a balancing score propensity analysis, 214 infants who underwent hybrid palliation and 831 infants who underwent nonhybrid management were proportionately matched regarding variables significantly associated with mortality and variables noted to significantly differ between groups. Overall survival between the 2 groups was adjusted by applying balancing scores to nonparametric estimates.

RESULTS

Compared with the nonhybrid management group, infants who underwent hybrid palliation had lower birth weight, smaller gestational age, and higher prevalence of in-utero interventions, noncardiac comorbidities, preoperative mechanical ventilation, absent interatrial communication, and moderate or severe mitral valve stenosis (all P values < .03). Unadjusted 12-year survival after hybrid palliation and nonhybrid management, was 55% versus 69%, respectively. After matching, 12-year survival after hybrid palliation versus nonhybrid management was 58% versus 63%, respectively (P = .37). Among matched infants born weighing <2.5 kg, 2-year survival after hybrid palliation versus nonhybrid management was 37% versus 51%, respectively (P = .22).

CONCLUSIONS

Infants born with critical left heart obstruction who undergo hybrid palliation have more high-risk characteristics and anatomy versus infants who undergo nonhybrid management. Nonetheless, after adjustment, there was no significant difference in 12-year survival after hybrid palliation versus nonhybrid management. Mortality remains high, and hybrid palliation confers no survival advantage, even for lower-birth-weight infants.

The Congenital Heart Surgeons' Society Kirklin/Ashburn Fellowship: The Fellows' Perspective

Since its establishment in 2001, the Congenital Heart Surgeons' Society John W. Kirklin/David Ashburn Fellowship has contributed substantially to the field of congenital heart surgery research while simultaneously training the next generation of surgeon- scientists. To date, ten fellows (and counting) have successfully completed this rigorous training, producing over 40 published articles focused on longitudinal outcomes from the various Congenital Heart Surgeons' Society cohorts. As the Kirklin/Ashburn Fellowship expands and additional fellows matriculate, its legacy, the network of support, and the contribution to congenital heart surgery research will undoubtedly hold strong.