Occult Progressive Pulmonary Arterial Occlusion Associated with Right Ventricular Hypertension in Patients with Systemic Arteriopathy

Abstract

Peripheral pulmonary artery stenosis (PPS) is a heterogeneous disease associated with numerous clinical or syndromic disorders including Williams syndrome. Previous studies focusing on patients with Williams syndrome have documented spontaneous improvement in branch pulmonary artery (PA) stenosis and right ventricular pressure. The goal of this study is to identify angiographic evidence of spontaneous occlusion or loss of segmental PAs in patients with PPS. Patients undergoing serial catheterization for PPS at Boston Children's Hospital between 1999 and 2014 were selected. Patients with structural heart disease such as tetralogy of Fallot, truncus arteriosus, transposition of the great arteries, or single ventricle were excluded. Hemodynamic data were extracted from catheterization reports, all available angiograms were reviewed, and evidence of segmental PA loss was documented based on defined angiographic criteria. Forty-two patients were included in the study. Each patient underwent an average of 5 catheterizations over the 15-year study period. The average RV pressure at initial catheterization was near systemic levels. Evidence of segmental PA loss was present in 40% of patients. Almost 30% of patients with vessel loss demonstrated loss at their initial catheterization, and 65% of patients experienced loss of multiple vessels over time. Patients with vessel loss tended to be older at initial catheterization and have higher average RV pressures at their most recent catheterization than those without vessel loss. Progressive segmental PA loss in patients with systemic arteriopathy and PPS has not been well described previously. In this cohort, segmental PA loss occurred in 40% of patients, resulting in persistently elevated PA pressures relative to patients who did not develop vessel loss. These findings highlight the importance of surveillance in this population of patients with systemic arteriopathy and severe PPS.