What is the prognostic significance of pulmonary hypertension in heart failure?

Increased left ventricular filling pressure is a hallmark of heart failure (HF) caused by left ventricular dysfunction (LVD). Within the closed hemodynamic system, increased LV filling pressure results in elevated pressures in the left atrium and pulmonary venous vasculature. When pulmonary hypertension (PH, defined by mean pulmonary artery pressure [mPAP] 25 mm Hg) is associated with an abnormally elevated pulmonary capillary wedge pressure (PCWP 15 mm Hg) or left ventricular end-diastolic pressure (LVEDP 18 mm Hg),1 it has been variably termed World Health Organization (WHO) Group 2 PH,1 pulmonary venous hypertension,2 “postcapillary PH,”3 or “passive PH.”4