Near-fatal haemorrhage from pulmonary arteriovenous malformation in HHT with increased cardiac output

Abstract

To the Editor: We read with interest the report by Montani et al. [1] of fatal rupture of pulmonary arteriovenous malformation (AVM) in a patient with hereditary haemorrhagic telangiectasis (HHT) and severe pulmonary arterial hypertension (PAH) confirmed by right heart catheterisation. The authors hypothesised that bleeding from pulmonary AVM may have been facilitated by increased mean pulmonary artery pressure ( P pa). Here, we report a patient with near-fatal haemorrhage from pulmonary AVM, probably facilitated by increased cardiac output, but without severe PAH. A 35-yr-old female nonsmoker, with a history of obesity and fenfluramide use 10 yrs previously for 2 months, was admitted for exertional dyspnoea during pregnancy. Arterial blood gases showed arterial oxygen tension ( P a,O2) of 8.2 kPa, and arterial carbon dioxide tension of 3.5 kPa, with markedly increased alveolar–arterial oxygen tension difference on 100% oxygen (74 kPa, normally <18.6 kPa). Chest radiograph revealed numerous pulmonary AVMs. Transthoracic contrast echocardiography showed estimated systolic P pa of 47 mmHg with moderate dilatation of the right heart cavities, and extracardiac right-to-left shunting. She had recurrent epistaxis since childhood, numerous characteristic telangiectasiae, and possible familial HHT in her paternal grandmother. HHT was diagnosed according to the Curacao criteria [2]. One deletion was found in exon 9 of the ENG gene, and analysis of the ACVRL1 gene was normal. Long-term oxygen therapy was initiated. Emergency caesarean delivery was performed at 25 weeks of gestation because of …