Evidence for palliative enlargement of the right ventricular outflow tract in severe tetralogy of Fallot.

Objective: If the pulmonary artery (PA) tree in patients with Fallot's tetralogy (TOF) is extremely hypoplastic, a shunt procedure may be difficult and not desirable because of side-effects. Moreover, the failing catch-up growth of the pulmonary annulus is well known. In patients with a severe form of TOF, we performed palliative transannular patching of the right ventricular outflow tract. The early and tong-term follow-up was evaluated. Methods: Eleven patients (93 days (10-245 days); 3.5 +/- 0.7 kg (2.5-4.3 kg)) had highly symptomatic TOF (Hb: 18 +/- 2 g/dl, SO2: 68 +/- 11%); angiographic diameters: RPA: 4.1 mm (2.5-6.4 mm), LPA: 3.4 mm (1.6-7.0 mm), PA trunc: 4.4 mm (2.5-7.0 mm). All. 11 underwent transannular enlargement of the right ventricular outflow tract without closure of the ventricular septum defect. A PA index (cross-sectional area of the pulmonary arteries to BSA) was used to compare pre- and postoperative data. For follow-up, the patients were repetitively examined clinically and echocardiographically. Results: Preoperative PA index was 87 +/- 40mm(2)/m(2) (normal: 330+35 mm(2)/m(2)). Postpalliation angiograms (age: 10-14 months) demonstrated a significant catch-up growth in nine patients (PA index from 99 +/- 40 to 310 +/- 54 mm(2)/m(2)) and inadequate growth in two patients (PA index 63 and 115 mm(2)/m(2)). Perioperative mortality was zero. Ten patients (43 months; 6-105 months) underwent elective repair. Six patients received pulmonary homograft valves (6-15 years after repair) because of severe pulmonary valve insufficiency and severe RV dilation. Complications: One patient died 10 months postpalliation due to pneumonia, one patient received a pacemaker after repair and died (2 months post-repair) due to pacemaker failure, a 5-year-old patient died 1 month after repair due to sepsis. All eight tong-term survivors (12-17years) are in excellent clinical condition. Echocardiography revealed good RV function and near normal diameters at peak systolic pressures between 25 and 50 mmHg. Only one patient developed brady-arrhythmia; a pacemaker was implanted 8 years after repair and 2 years after homograft implantation. Conclusions: In a very severe form of TOF, palliative right ventricular outflow tract construction may provide the potential for complete repair. In the presented high-risk patient group, mortality was not related to the hypoplastic pulmonary arteries. Obviously, all. patients need pulmonary valve implantation in the tong run. (c) 2005 Elsevier B.V. All rights reserved.