COMPression of Left Main coRonary artEry in patientS With Pulmonary Arterial Hypertension aSymptomatIc fOr aNgina

The prevalence of critical ab extrinsic compression of left main coronary artery (LMCA) is very high in patients with pulmonary arterial hypertension (PAH) symptomatic for angina (up to 40% according to a recent study of 121 patients with PAH). The element that most of all correlates with the degree of coronary stenosis is the diameter of the pulmonary artery (PA). In particular, a diameter ≥ 40 mm has a sensitivity of 83% and a specificity of 70% in patients with angina. Critical stenosis of LMCA is a risk factor for sudden death and in these condition percutaneous coronary angioplasty with stent implantation has proven to be a safe and effective long-term procedure. Preliminary data from a retrospective analysis of the registry of patients with PAH in Bologna (ARCA registry, 109/2016/U/Oss) highlights that even in PAH patients asymptomatic for angina, compression of LMCA can occur in up to 13% of patients and the main predictive parameter of compression was found to be a diameter ≥ 42 mm (with a sensitivity of 87% and a specificity of 77%). Performing a screening test by coronary-CT scan in all subjects suffering of PAH with a PA diameter ≥ 40 mm even if asymptomatic for angina could therefore help to identify patients with PAH at increased risk for sudden death at an early stage.