Abstract 12221: Low Nasal Nitric Oxide as a Biomarker for Increased Pulmonary Vascular Resistance in Congenital Heart Disease

Introduction: Pulmonary arterial hypertension (PAH) reflected by increased pulmonary vascular resistance (PVR) is an important cause of mortality and morbidity in congenital heart disease (CHD). In CHD patients, injury by shear stress from shunting lesions is associated with impaired production of endothelial derived nitric oxide (NO), which plays an essential role in regulating pulmonary vascular tone. We hypothesized CHD patients with increased PVR will have low NO. Given difficulty in measuring NO systemically, we used nasal NO (nNO) as a proxy for systemic NO. Methods: This study is a single center retrospective chart review of 207 patients with CHD (2010-2016). Patients were subdivided into biventricular (BV) and single ventricular (SV) physiology. Hemodynamic data was obtained from cardiac catheterization records. We measured nNO using ATS/ERS guidelines and classified them as low or normal based on published, age-specific cutoff values. PAH was defined per AHA/ATS guidelines (Table 1). Results: Mea...