Stage 1 hybrid palliation for hypoplastic left heart syndrome—assessment of contemporary patterns of use: An analysis of The Society of Thoracic Surgeons Congenital Heart Surgery Database

Abstract

Objective Hybrid palliation is an alternative to Norwood stage 1 for the initial management of hypoplastic left heart syndrome. Contemporary multicenter hybrid use and institutional/patient factors associated with hybrid use relative to the Norwood have not been evaluated. We describe hybrid use in relation to institutional volume, patient factors, and short-term outcomes. Methods Infants aged 60 days or less listed in The Society of Thoracic Surgeons Congenital Heart Surgery Database (2010–2012) undergoing initial palliation of hypoplastic left heart syndrome were included. Annual institutional hybrid use rates were calculated: [hybrid procedures/(Norwood + hybrid + transplant procedures)]. In-hospital outcomes for primary hybrid and primary Norwood were compared and stratified by high (defined as ≥50%) versus low (defined as ≤10%) institutional hybrid use. Results Of 1728 patients (100 centers), most (n = 1496, 87%) underwent an index Norwood; 232 patients (13%) underwent an index hybrid procedure. Preoperative patient risk factors were more prevalent in patients undergoing the hybrid procedure. Only 13 of 100 institutions were high hybrid users, and these tended to have lower annual hypoplastic left heart syndrome index case volume. Unadjusted in-hospital mortality was higher for the hybrid compared with the Norwood procedure (30%vs 16%; P<.001). In-hospital mortality for the hybrid procedure was not associated with hybrid use (26%among institutions with low use vs 28%among institutions with high use). However, centers with high hybrid use had higher mortality after the Norwood (43%) compared with centers with low hybrid use (16%). Conclusions Few centers currently select the hybrid procedure for most infants with hypoplastic left heart syndrome. Although unadjusted in-hospital hybrid mortality is higher than Norwood mortality, potential risk factors are more prevalent among hybrid cases. Institutions with higher hybrid use have lower hypoplastic left heart syndrome case volume and higher Norwood mortality.

Transplantation and Mechanical Circulatory Support in Congenital Heart Disease

“…The procedure has been used by many centers but deployed preferentially over the Norwood procedure by only a few. 50 Most centers select the hybrid approach for high-risk Norwood candidates (those with prematurity, low birth weight, hemodynamic instability, or brain or other noncardiac conditions that could affect the safety of aortic reconstruction at birth) and for those who may be able to undergo a 2-ventricle repair later. 51 Some of these patients do eventually go on to receive a transplant.…”

“…51 Some of these patients do eventually go on to receive a transplant. 50,52 Despite the fact that some high-risk Norwood candidates may be offered primary transplantation, no study to date has specifically described the use of the hybrid approach as a bridge to transplantation.…”

Hybrid palliation for hypoplastic left heart syndrome: Navigating the gray zone

“…For this reason, we did not include completeness of revascularization in our analysis. Whereas their series 1 suggested that completeness of revascularization increases the benefit from TAR, the reverse has been reported by Kieser and colleagues, 3 who suggested that in their Canadian experience the use of arterial grafts in fact negated (or mitigated) the impact of incomplete revascularization. 3 (3) The application of TAR in our series has been broader than that reported in their 1 and other published series, which likely reflects some international differences in practice, although we believe that the results can be generalized.…”

“…Whereas their series 1 suggested that completeness of revascularization increases the benefit from TAR, the reverse has been reported by Kieser and colleagues, 3 who suggested that in their Canadian experience the use of arterial grafts in fact negated (or mitigated) the impact of incomplete revascularization. 3 (3) The application of TAR in our series has been broader than that reported in their 1 and other published series, which likely reflects some international differences in practice, although we believe that the results can be generalized. We are not certain, however, whether the use of TAR could be even higher, as our colleagues have suggested, because of the rise in radial angiography and uncertainty regarding the safety of using as bypass conduits radial arteries that have been cannulated for angiography.…”

“…2 Compared with patients undergoing the stage 1 Norwood procedure, those who undergo a hybrid procedure usually have higher prevalences of prematurity, low birth weight, chromosomal abnormalities, and unstable preoperative hemodynamics. 3 Davies and colleagues 1 have succeeded in demonstrating that patient's risk factors are not always mitigated by the hybrid procedure, and in about 28% of the cases an early stage 1 Norwood procedure may be required. In their experience, 8 patients underwent an unplanned stage 1 Norwood procedure after a complete hybrid palliation: indications were progressive hypoxia, resolution of contraindication to cardiopulmonary bypass, increased flow acceleration through the ductal stent or recoarctation, and excessive pulmonary blood flow.…”