Extrinsic compression of left main coronary artery by aneurysmal pulmonary artery in severe pulmonary hypertension: its correlates, clinical impact, and management strategies.

Aims: Although left main coronary artery (LMCA) compression (Co) by pulmonary artery (PA) aneurysm (A) has been reported in some pulmonary hypertension (PH) series, clinical importance and management of this complication remain to be determined. In this single-centre prospective study, we evaluated correlates, clinical impact, and management strategies of LMCA-Co in patients with PH.

Methods and results: Our study group comprised 269 (female 166, age 52.9 ± 17.3 years) out of 498 patients with confirmed PH who underwent coronary angiography (CA) because of the PAA on echocardiography, angina or incidentally detected LMCA-Co during diagnostic evaluation with multidetector computed tomography. The LMCA-Co ≥ 50% was documented in 22 patients (8.2%) who underwent CA, and stenosis were between 70% and 90% in 14 of these. Univariate comparisons revealed that a younger age, a D-shaped septum, a higher PA systolic, diastolic, and mean pressures and pulmonary vascular resistance, a larger PA diameter, a smaller aortic diameter and pulmonary arterial hypertension associated with patent-ductus arteriosus, atrial or ventricular septal defects were significantly associated with LMCA-Co. Bare-metal stents were implanted in 12 patients and 1 patient underwent PAA and atrial septal defect surgery and another one declined LMCA stenting procedure.

Conclusion: Our study demonstrates that LMCA-Co is one of the most important and potentially lethal complications of severe PH, and alertness for this risk seems to be necessary in specific circumstances related with PAA. However, long-term benefit from stenting in this setting remains as a controversy.