Impact of pre–stage II hemodynamics and pulmonary artery anatomy on 12-month outcomes in the Pediatric Heart Network Single Ventricle Reconstruction trial

Abstract

Objective To compare interstage cardiac catheterization hemodynamic and angiographic findings between shunt types for Single Ventricle Reconstruction (SVR) trial. Background The SVR trial, which randomized subjects to modified Blalock-Taussig shunt (MBTS) or right ventricle-to-pulmonary artery shunt (RVPAS) for the Norwood procedure, demonstrated RVPAS was associated with smaller pulmonary artery diameter, but superior 12-month transplant-free survival. Methods We analyzed pre-stage II catheterization data for SVR trial subjects. Hemodynamic variables and shunt and pulmonary angiography were compared between shunt types; their association with 12-month transplant-free survival was also evaluated. Results Of 549 randomized subjects, 389 underwent pre-stage II catheterization. Smaller size, lower aortic and superior vena cava saturation, and higher ventricular end-diastolic pressure (EDP) were associated with worse 12-month transplant-free survival. MBTS subjects had lower coronary perfusion pressure (27mmHg vs. 32mmHg, P<0.001) and higher Qp:Qs ratio (1.1 vs. 1.0, P=0.009). Higher Qp:Qs ratio increased the risk of death or transplant only in the RVPAS group (P=0.01). MBTS subjects had fewer shunt (14% vs. 28%, P=0.004) and severe left pulmonary artery stenoses (0.7% vs. 9.2%, P=0.003), larger mid-main branch pulmonary artery diameters and higher Nakata index (164 vs. 134, P<0.001). Conclusions Compared with RVPAS subjects, MBTS subjects had more hemodynamic abnormalities related to shunt physiology, while RVPAS subjects had more shunt or pulmonary obstruction of a severe degree, and inferior pulmonary artery growth at pre-stage II catheterization. Lower BSA, higher ventricular EDP, and lower SVC saturation were associated with worse 12-month transplant-free survival.

Right ventricular morphology and function following stage I palliation with a modified Blalock–Taussig shunt versus a right ventricle-to-pulmonary artery conduit

“…The modified Blalock–Taussig (MBT) shunt involves a connection between the innominate or subclavian artery and one of the branch pulmonary arteries. In some studies, the MBT shunt has been associated with haemodynamic instability [2] and sudden death [3] in the postoperative period. The right ventricle-to-pulmonary artery (RVPA) conduit was developed to offset this risk [4].…”

Technical and anatomical factors affecting the size of the branch pulmonary arteries following first-stage Norwood palliation for hypoplastic left heart syndrome

“…The size of the branch pulmonary arteries (BPAs) significantly influences the efficiency of the Fontan circulation [1,2]. Both central BPA stenosis and small left pulmonary artery (LPA) are known problems with the classical Norwood and its Sano modification [3,4]. Although this problem is documented since early reports, there is very little research into the factors influencing such problems [5].…”

Practice Variation in Single-Ventricle Patients Undergoing Elective Cardiac Catheterization: A Report from the Congenital Cardiac Catheterization Project on Outcomes (C3PO)

“…10,27,28 Disproportionate left PA interventions would not have been predicted based upon the early results from the PHN Single-ventricle Reconstruction trial, which demonstrated a greater burden of right PA stenosis at the pre-BCPA catheterization. 29 Use of spontaneous ventilation was most common in the post-Fontan cohort, likely reflecting the increased age, size, and overall stability of this more mature cohort. Although the impact of assisted ventilation on acute postoperative hemodynamics has been assessed previously in stage II and Fontan palliated patients, [30][31][32] no prior reports have examined the relation of airway management to invasive hemodynamics in the setting of elective catheterization.…”