Pulmonary artery pressure is associated with extracellular volume fraction in patients with normal left ventricular function

Background Elevated pulmonary artery pressures (PAP) from type II pulmonary hypertension (PH) is caused by a heterogeneous group of disorders. Myocardial fibrosis (MF) is a common pathological finding in many cardiovascular diseases; however its relationship with PAP is not well characterized. In particular, among patients with heart failure and preserved ejection fraction (HFpEF), MF may be a pathophysiologic mechanism contributing to disease severity and poor outcomes. This paradigm would be strengthened if MF were demonstrated to independently predict PAP in HFpEF. Cardiac MRI techniques quantifying extracellular volume matrix (ECV), are well validated markers of MF and may provide more comprehensive assessment over traditional late gadolinium enhancement (LGE) techniques. Thus, the goal of this study was to demonstrate that ECV is an independent predictor of PAP, particularly in patients with preserved left ventricular ejection fraction (EF).