DEVELOPMENT OF THE PULMONARY ARTERIES AFTER THE NORWOOD PROCEDURE: COMPARISON BETWEEN BLALOCK-TAUSSIG SHUNT AND RIGHT VENTRICULAR-PULMONARY ARTERY CONDUIT
Joseph Caspi, Timothy W. Pettitt, Theodorus Mulder, Aluizio Stopa
Division of Cardiothoracic Surgery and Pediatric Cardiology, Louisiana State University, New Orleans, Louisiana, USA
Background: The Norwood-Sano procedure for HLHS has been associated with improved postoperative hemodynamics and outcome. To assess the effect on the development of the pulmonary arteries (PA), the size of the PA was compared between patients with a BT shunt and right ventricular-PA conduit before Bidirectional Glenn (BDG).
Methods: Between January 2000 and May 2006, 36 patients with HLHS underwent BDG. Group A (n=19) had a BT shunt, 3.5 mm in 15 patients, and 4 mm in 4. Group B (n=17) had right ventricular-PA conduit with a 5 mm Gore-Tex tube. Mean age at operation was 7 ± 1.5 months in group A, and 5 ± 1 months in group B (NS). There was no difference in mean weight, hematocrit, arterial oxygen saturation or ventricular function between the groups. All patients had cardiac catheterization and echocardiograms prior to surgery.
Results: Total PA (Nakata) index was 192 ± 10 mm2/m2 in group A, and 238 ± 18mm2/m2 in group B (p = 0.03). In group B, the diameters of the left and right PA were comparable, whereas, in group A the left PA was smaller than the right PA (p = 0.05). Significant stenosis occurred at the insertion site of the BT shunt in 2 patients in group A, and central branch stenosis was present in 1 patient in group B (NS). There were no early or late deaths. The mean PA pressure at the end of BDG was 14 ± 2 mmHg in group A and 11 ± 1 mmHg in group B (p = 0.06). Persistent pleural effusion (>10 days) occurred in 3 patients in group A, and 1 patient in group B (NS). Arterial oxygen saturation was higher after surgery in group B, 80 ± 2% compared with 74 ± 2% in group A (p = 0.05).
Conclusions: The Norwood procedure with right ventricular–PA conduit may have favorable effects on the development of the PA due to even distribution of pulmonary blood flow