A Tale of Grumpy Neighbours: Angina from Left Main Coronary Artery Compression in Severe Pulmonary Hypertension with Large ASD

This report presents a case of a 42-year-old patient diagnosed with ostium secundum atrial septal defect (ASD) with severe pulmonary arterial hypertension (PAH). The patient presented with progressive chest pain and dyspnea and was found to have a lesion in the left main coronary artery (LMCA) ostium by coronary angiography. Computed tomography (CT) imaging revealed a significant enlargement of the main pulmonary artery (MPA), which indicated possible compression of the LMCA by the pulmonary artery which was subsequently confirmed by coronary angiography and intravascular ultrasound (IVUS). Our patient underwent IVUS guided percutaneous coronary intervention by which a stent was deployed in the ostial LMCA, leading to near resolution of the patient's symptoms. Currently, the patient is under follow-up. This case highlights an often-overlooked cause of chest pain and dyspnea in patients with PAH. Although these patients often experience typical and atypical angina due to elevated right-sided pressures, the current report reveals that external compression of the LMCA by an enlarged pulomonarya artery(PA) can also cause coronary ischemia. Physicians should consider LMCA compression when assessing PAH patients with chest pain, as percutaneous coronary intervention and stenting can safely and effectively manage this condition.