https://orcid.org/0000-0002-7491-5305
A 50-year-old woman was referred to our hospital due to facial swelling and dyspnoea. She had been diagnosed with ventricular septal defect (VSD) at 5 years old but did not undergo VSD closure due to a diagnosed Eisenmenger syndrome. Although she had been treated with triple combination therapy with pulmonary vasodilators, i.e., macitentan (10 mg/day), tadalafil (30 mg/day), and epoprostenol (34 ng/kg/min), her pulmonary arterial (PA) pressure remained high (mean, 98 mmHg). Chest X-ray indicated an enlarged right PA with the increasing diameters from 5 to 10 cm over 6 years (Panel A, arrowheads). Computed tomography pulmonary angiogram suggested that the giant aneurysm of the right PA compressed the superior vena cava. Thus, the patient was diagnosed with superior vena cava syndrome associated with the right PA aneurysm. The PA aneurysm had a thrombosed multilayer wall (Panel B). She had refractory right heart failure and eventually died of haemoptysis and hypoxaemia. The autopsy revealed that the right PA was a ‘Mille-Feuille’-like giant dissecting aneurysm (Panels C and D, asterisk indicate true lumen of PA), and the dissected lumen was filled with multilayer organized thrombi.
Pulmonary hypertension is one of the leading causes of PA aneurysms; however, little is known about the concomitant PA dissection and its pathogenesis. Pulmonary hypertension increases the PA wall stress, resulting in a long-term disruption of elastic fibres of the media. In this case, the fragmentation of elastic fibres was sporadically observed in bilateral PAs (Panel E, arrowheads).
The Eisenmenger syndrome has a long clinical course, and its life expectancy is reportedly about 40 years. Therefore, accumulation of the medial degeneration increases the risk of PA aneurysm development, resulting in PA dissection. Images in this report would be used to identify the risk of PA dissection in patients with pulmonary hypertension with PA aneurysms.
