Prolonged QRS Duration: A New Predictor of Adverse Outcome in Idiopathic Pulmonary Arterial Hypertension

Abstract

A prolonged QRS duration ( ≥ 120 milliseconds) predicts outcomes in patients with left-sided heart failure, but the impact in idiopathic pulmonary arterial hypertension (IPAH) and right-sided heart failure is unknown. We assessed the prognostic value of a prolonged ECG QRS duration in patients with IPAH in China. We retrospectively analyzed the initial 12-lead ECG for QRS duration in 212 consecutive patients with IPAH seen at our center between 2007 and 2009. Patients were divided according to QRS duration < 120 milliseconds or ≥ 120 milliseconds. The baseline characteristics and survival of the two groups were compared. Thirty-five patients with IPAH (16.5%) had a QRS duration ≥ 120 milliseconds, including 21 (9.9%) with right bundle-branch block and 14 (6.6%) with nonspecific intraventricular conduction delay. Prolongation of the QRS duration was associated with a worse World Health Organization functional class and 6-min walk test distance and higher serum uric acid when compared with patients with normal QRS duration (P < .05). Prolonged QRS duration was an independent predictor of mortality and was associated with a 2.5-fold increased risk of death (P = .024). Prolongation of the QRS duration is associated with clinical severity in patients with IPAH. In addition, QRS prolongation has an independent association with cardiopulmonary mortality and could be a new predictor of adverse outcome in patients with IPAH.