Efficacy of the 'intrapulmonary-artery septation' surgical approach for Fontan candidates with unilateral pulmonary arterial hypoplasia†.

Abstract

The bilaterally unbalanced development of pulmonary arteries (PAs), as a result of unilateral pulmonary arterial hypoplasia (PAhypo) makes patients either ineligible for the Fontan operation or candidates for the one-lung Fontan operation. In the present study, we examined the efficacy of intrapulmonary-artery septation (IPAS), a technique we reported in 2007 in which a septation is constructed within the central PA, in patients with unilateral PAhypo. Sixteen patients with unilateral PAhypo and an affected PA index of ≤60 mm(2)/m(2), including non-confluent PA (NCPA), underwent IPAS between January 2000 and March 2012; patients with pulmonary venous obstruction were excluded from this study. We compared the affected PA index values before and after IPAS and after the Fontan operation as well as the bilateral pulmonary blood flow ratio using pulmonary scintigraphy. The post-Fontan operation values of central venous pressure (CVP), pulmonary vascular resistance (PVR), ventricular end-diastolic pressure (VEDP), cardiac index (CI) and arterial oxygen saturation (SaO2) at the most recent cardiac catheterization, as well as the pre-IPAS and post-Fontan New York Heart Association (NYHA) classification levels were examined. One patient died after IPAS (survival rate, 93.8%). Thirteen (86.7%) of the surviving 15 patients underwent the Fontan operation. The mean PA indexes were 25.5 ± 18.9 mm(2)/m(2) before IPAS and 67.9 ± 34.2 mm(2)/m(2) after IPAS (P = 0.003); the mean PA index was 71.1 ± 50.0 mm(2)/m(2) after the Fontan operation. Restenosis did not occur after the Fontan operation, and the PA diameters were maintained. The mean affected/unaffected lung blood flow ratio was 0.89 ± 0.67. The most recent cardiac catheterization after the Fontan operation indicated the following values: CVP, 11.7 ± 1.8 mmHg; PVR, 1.3 ± 0.4 U m(2); EDP, 5.7 ± 2.0 mmHg; CI, 3.1 ± 0.5 l/min/m(2) and SaO2, 94.9 ± 2.0%. The mean pre-IPAS and post-Fontan NYHA levels were 2.3 ± 0.6 and 1.2 ± 0.4, respectively (P = 0.0002). With IPAS, the affected PA diameters increased significantly, and were maintained after the Fontan operation, and continuity of the native PAs was achieved. IPAS is very effective for patients suffering from otherwise intractable diseases.