Severe pulmonary arterial hypertension in a patient with hereditary hemorrhagic telangiectasia and multiple pulmonary and hepatic arteriovenous malformations

Abstract

Hereditary hemorrhagic telangiectasia (HHT) is a genetic disorder in which there is faulty development of the arteries. There is a high incidence of pulmonary hypertension (PH) in these patients, the pathophysiology of which is not fully known. An increase in cardiac output, causing high-output cardiac failure, and increased pulmonary vascular resistance secondary to genetic mutations are the main reasons. We report a 25-year-old male with HHT who presented with right heart failure secondary to PH in whom both the above mechanisms were operating. The coexistence of giant pulmonary arteriovenous malformations with severe PH is a rare scenario influencing management decisions that are discussed. In addition, this patient highlights the classical visceral vascular malformations in this rare disorder.

Pulmonary hypertension in hereditary hemorrhagic telangiectasia: A clinical review

“…40 While the majority of hemodynamic profiles of patients with HHT and PH secondary to HOHF demonstrate isolated postcapillary PH, a considerable number of studies reports combined pre-and postcapillary PH. [41][42][43] This may be due to mild pulmonary arterial remodeling in the setting of chronic exposure to increased blood flow. However, investigations have also highlighted an unmasking of heritable pulmonary arteriopathy following successful treatment of initial HOHF symptoms as well as cases of portopulmonary hypertension concomitant with HOHF-mediated PH.…”

“…This may be due to mild pulmonary arterial remodeling in the setting of chronic exposure to increased blood flow. However, investigations have also highlighted an unmasking of heritable pulmonary arteriopathy following successful treatment of initial HOHF symptoms as well as cases of portopulmonary hypertension concomitant with HOHF‐mediated PH 42,44 . In the case of the latter, patients have presented with symptoms of HOHF as well as hepatic encephalopathy 45 .…”

“…While the majority of hemodynamic profiles of patients with HHT and PH secondary to HOHF demonstrate isolated postcapillary PH, a considerable number of studies reports combined pre‐ and postcapillary PH 41–43 . This may be due to mild pulmonary arterial remodeling in the setting of chronic exposure to increased blood flow.…”

“…However, investigations have also highlighted an unmasking of heritable pulmonary arteriopathy following successful treatment of initial HOHF symptoms as well as cases of portopulmonary hypertension concomitant with HOHF‐mediated PH. 42 , 44 In the case of the latter, patients have presented with symptoms of HOHF as well as hepatic encephalopathy. 45 Furthermore, one study has shown that 40% of patients with HHT have elevated ammonia levels.…”