Left main coronary artery compression by a dilated main pulmonary artery and left coronary sinus of Valsalva aneurysm in a patient with heritable pulmonary arterial hypertension and FLNA mutation

Left main coronary artery (LMCA) disease due to external compression by a dilated main pulmonary artery (MPA) is an uncommon clinical entity. Here, we describe a 52-year-old woman with pulmonary arterial hypertension (PAH) and anteroseptal old myocardial infarction (OMI). The cause of the OMI was external compression of the LMCA by the dilated MPA and aneurysm of the left coronary sinus of Valsalva. The patient’s sister (aged 56 years) had also been diagnosed with PAH and both women had a novel heterozygous splicing mutation, IVS2-2A > G (c.374-2A > G in NM_001456), in the filamin A (FLNA) gene. To our knowledge, this is the first report of HPAH which is likely to be due to FLNA mutation and compression of the LMCA between a dilated MPA and aneurysm of the left coronary sinus of Valsalva.