The difficult diagnosis of pulmonary vascular disease in heart failure

Pulmonary hypertension (PH), defined as a mean pulmonary arterial pressure (PAP) ≥25 mmHg, is a well-recognised complication of left heart disease (LHD). PH prevalence is variable ranging from 25% to 80% of LHD patients according to the methods of assessment, cut-off values and characteristics of the patient population [1–3]. All aetiological types of LHD are affected, including heart failure with reduced (HFrEF) or preserved (HFpEF) left ventricular ejection fraction, and valvular LHD. The presence of PH-LHD is associated with advanced symptoms, reduced exercise capacity and impaired outcome after medical, interventional or surgical therapy [1, 3, 4]. The relevance of PH-LHD is highlighted by the recognised epidemiological predominance of this condition, which represents the most common form among the five groups included in the PH clinical classification, accounting for 65–80% of the PH cases [1, 3, 5, 6]. PH-LHD is distinctively characterised by an increase of the pulmonary artery wedge pressure (PAWP) >15 mmHg [5, 6], an accepted surrogate for left atrial pressure.