Pulmonary arterial hypertension (PAH), is a progressive disease with fatal outcome. A detailed evaluation of patient with PAH is necessary before initiation of therapy. Congenital extrahepatic porto-systemic shunts (Abernathy malformation) are rare but often missed as a potential cause of (PAH). If identified and closed, this can be an important cause of treatable PAH. We present a case series of patients with PAH and Abernathy malformation.
Materials and methods:
This is a retrospective analysis of a single centre experience of patients with PAH and Abernathy malformation. From June 2014- Aug 2019. All patients referred at our centre for PAH undergo detailed evaluation including USG abdomen and portal venous Doppler. The children who were suspected to have portocaval abnormalities on USG underwent CT angiogram to confirm the diagnosis. Patients underwent closure of the shunt when feasible. Pre and post procedure functional class, echocardiogram and medication requirement was recorded for all patients.
We encountered 7 patients (Median age = 13 years, range = 3.5years= 16 years) with PAH who on evaluation also had Abernathy malformation. 5/7 patients presented with dypsnea on exertion and 2/7 presented with syncope. All patients were diagnosed to have “idiopathic PAH” at outside centres and were referred to us for evaluation and management. All the children had moderate to severe PAH on initial echocardiography at our centre. 6/7 patients were on dual pulmonary vasodilators (PDE5 inhibitors and ET receptor blockade) and 1 patient was on PDE5 inhibitor at presentation. On evaluation at our centre, 6/7 were diagnosed to have Abernathy malformation type 2 and 1 was diagnosed to have Abernathy malformation type 1 On USG abdomen and portal venous Doppler. 6/7 patients underwent cardiac catheterization with balloon occlusion of the Abernathy malformation. At Baseline mean PA pressures were 56 + 14 mm Hg and PVRi of 6.7 + 2 Woods units.m2. At baseline portal pressures were 8 + 2 mm Hg, there was an increase in portal pressures of 3 mm Hg (Range= 2-8 mmHg) after balloon occlusion of the lesion. 3/6 patients with Type 2 Malformation underwent device closure and 1 underwent surgical closure as the malformation was not suitable for device closure. 2 patients were lost to follow up. At follow up, median duration of 8 months (3 months – 11 months), one patient had complete normalisation of PA pressure an is now off pulmonary vasodilators and the remaining 2 are on single drug (PDE5 inhibitor) with mild PAH on echocardiogram. There was a significant improvement in functional class IV vs II (range I-II), p = 0.03 in all patients who underwent closure of the malformation.
Abernathy malformation is a rare but potentially treatable cause of PAH in children. All patients with PAH should undergo USG abdomen and portal venous Doppler to identify and treat this disorder.