Prognostic value of pulmonary artery diameter in patients with pulmonary arterial hypertension

Abstract

Abstract Background Pulmonary artery (PA) dilation is common in pulmonary arterial hypertension (PAH) and may cause left main coronary artery (LMCA) compression. This complication have been sistematically evaluated in patients with angina but no evidence is available for patients asymptomatic for angina. Purpose To evaluate the prognostic value of PA diameter and the prevalence of LMCA compression in PAH patients with and without angina. Methods All patients with PAH and a baseline angio-CT scan were included. The last angio-CT scan performed was considered for PA diameter increase velocity calculation. Patients with angina or radiological signs of suspected LMCA compression underwent a coronary (cor)-CT scan. Patients with a not negative cor-CT underwent invasive coronary angiography. If clinically indicated invasive coronary angiography was performed without a preliminary cor-CT. To evaluate the predictivity for compression at coronary angiography the PA diameter at cor-CT or at the nearest angio-CT scan was considered. Results 958 patients were included. PA diameter at baseline is higher in patients with congenital heart disease (CHD) and is not predictive of death. The velocity of PA diameter increase is lower in patients with connective tissue disease and is a risk factor for death in both overall population and different etiological subgroups except CHD and pulmonary veno-occlusive disease. 180 patients had angina and 50 had LMCA compression. 120 patients without angina underwent cor-CT and/or coronary angiography and 15 patients had LMCA compression. The best PA diameter cut-offs predicting LMCA compression in symptomatic/asymptomatic patients were, respectively, 40/42 mm (sensitivity and specificity, respectively, 80 and 72%/87 and 77%). Conclusion 28% of patients with angina and 13% of patients without angina had LMCA compression. We found a similar PA diameter predicting LMCA compression in patients with or without angina. PA diameter, instead, was not predictive of prognosis (maybe because most deaths were related to heart failure and also because patients with LMCA compression were treated with stenting, possibly preventing sudden cardiac death). Eventually, PA diameter velocity increase is associated with prognosis but this may only reflect a severe disease refractory to medical therapy. Funding Acknowledgement Type of funding source: None