Background: Pulmonary arterial hypertension (PH) is a rare syndrome with complex aetiology that requires multimodality imaging for complete diagnosis, especially in congenital heart disease (CHD). Adults with CHD – associated PH may benefit from pulmonary vasodilator drugs, but PH complications such as left main coronary artery extrinsic compression may re-quire Heart Team discussions for risk assessment and best management.
Case presentation: A 54 year-old woman known with hepatitis C and Child-Pugh class A liver cirrhosis, on interferon and ribavirin (with persistent viraemia), describes low exercise tolerance, confirmed by the 6 minute walk test (320 m). She has low SatO₂ (94%), but otherwise normal clinical exam and BNP. Echocardiography shows signs of PH: dilated main pulmonary artery (PA) and right heart chambers, mean PA pressure (mPAP) 38 mmHg, short pulmonary acceleration time with midsystolic notching, no left heart disease.
Porto-PH is unlikely in absence of signs of portal hyper at upper gastrointestinal endoscopy. Chest CT finds no signs of thromboembolic disease, it does show signs of PH and more importantly it is relevant for si-nus venosus type of atrial septal defect (ASD) and par-tial anomalous pulmonary venous return, the upper ri-ght pulmonary vein draining in the superior vena cava. Catheterisation is diagnostic for precapillary PH (mPAP 38 mmHg, pulmonary capillary wedge pressure 7 mmHg) with PVR 3.07 WU and 5.15 WUi, PVR/SVR 0.14, cardiac index 2.33 L/min/m², Qp:Qs 2.89 consis-tent with the sinus venosus type ASD and the partial anomalous return. Coronarography was performed showing 60% left main coronary artery, LMCA steno-sis, with instant wave-free ratio (iFR)=1 which allowed witholding PCI.
We considered ASD surgical correction but given the patient’s age, associated cirrhosis, the bidirectional shunt, PH and especially the „natural septostomy” as pressure-release valve for the RV, we chose a brigde-to-decision strategy (PH medication and repeat cath). Bo-sentan is prefered for CHD – associated PH, but can ca-use hepatolysis and new antiviral therapy for hepatitis C was needed. Lacking data on co-administration and considering stable PH vs. persistent viraemia, antivirals were started first. Bosentan was initiated later without hepatocytolysis. Repeat cath at 3 months showed un-changed haemodynamic parameters, with PAP ≥50% aortic pressure – unsuitable for shunt correction. Bio-logical and echographic parameters evolved favourably with bosentan at 1-year follow-up.
Discussions: Our case is relevant from multiple stan-dpoints. Firstly, bosentan (class I recommendation for CHD-associated PH) was well tolerated on a cirrhotic liver and vice-versa, ombitasvir/ paritaprevir/ ritonavir was well tolerated in a PH patient (no literature data on the association). Secondly, PVR 5.3 WUi is in the grey zone of the ASD correction in guidelines, but repeat cath after 3 months of pulmonary vasodilator therapy confirmed the anticipated irreversibility of PH. Thirdly, in lack of counsel regarding an asymptomatic 60% left main compression in PH Guidelines, we turned to the guidelines on revascularisation and performed an ischaemia test which allowed witholding a risky intervention. This is, to our knowledge, the first application of iFR in a case of LMCA compression and in a case of PH altogether.
Conclusions: Challenges for both the cardiologist and the current Guidelines are a reminder that case reports are essential in shedding some light on rare associations – here, grown-up congenital heart disease (GU-CHD) and pulmonary arterial hypertension (PH) with complications (left main coronary artery stenosis) and comorbidities (viral liver cirrhosis).