Introduction: Pulmonary arterial hypertension (PAH) is a rare, but disabilitating syndrome, and the idiopathic form is associated with some of the highest morbidity and mortality rates despite administration of specific pulmonary vasodilator therapy – available in our coun-try via the National PAH Programme. When unfavou-rable evolution and mechanical complications emerge, combination therapy, percutaneous interventional and even surgical (pulmonary transplantation, pulmonary artery plasty) procedures are life-saving.

Methods: A 33 year-old female was examined in our Clinic in 2005 for low exercise capacity, performing 399 m at the 6 minute walk test (6MWT), with low SatO2 and BNP of 115 pg/ml. She was diagnosed with PH at echocardiography (elevated medium pulmonary artery pressure, mPAP, aneurysmal main pulmonary artery, but normal right ventricle systolic function) and catheterisation showed arterial PH (elevated pul-monary vascular resistance, PVR and low pulmonary capillary wedge pressure, PCWP). Diagnosis of exclusi-on was idiopathic PAH (normal left heart, normal viral and autoimmune lab tests, no pulmonary thrombotic or parenchymal disease on chest CT, no hepatorenal disease).

Results: She was started on pulmonary vasodilator the-rapy when this became available in our country via Na-tional PAH Programme, in 2008 – initial monotherapy with sildenafil, with good response (460 m at 6MWT, BNP 82 pg/ml), then up-titrated to maximum dose in 2015 because of deteriorating exercise capacity (330 m), also requiring double-therapy – bosentan between 2009-2011 (stopped because of hepatic cytolysis), then ambrisentan between 2014-2015. After interruption of ambrisentan (which became nationally unavailable) her clinical, biologic and imaging status deteriorated (295 m at 6MWT, BNP 125 pg/ml), but soon maci-tentan became available in 2016 and was administered without side effects and with good prognostic impact (420 m at 6MWT, BNP 101 pg/ml). In 2017 she had repeat catheterisation because of deteriorating exercise capacity (mPAP 51 mmHg, PCWP 8 mmHg, PVR 14 Wood units, good PAH mortality prognostic factors: right atrial pressure, RAP 4 mmHg, SvO2 74%, cardiac index 2.99 l/m2). Coronarography was also performed because she had developed exercise angina, and found 60% stenosis of the left main coronary artery (LMCA) with pencil-tip shape suggestive for extrinsic compre-ssion by the aneurysmal pulmonary artery (61 mm at chest CT). In 2019, because of persistent angina and decreasing exercise capacity, despite stationary and favourable haemodynamic parameters, and in light of recent studies, she had repeat coronarography showing progression of LMCA stenosis to 80% so angioplasty was performed. She is awaited for follow-up.

Conclusions: Recent PAH Guidelines recommend up-front combination therapy as therapeutic gold-standard approach by mortality risk stratification in medium or high-risk patients (and may even be considered in low risk patients). However, pulmonary vasodilator me-dication does not prevent mechanical complications, which may require interventions – here, a nation-wide unique procedure of left main angioplasty because of extrinsic compression.