Long-term follow-up of hereditary hemorrhagic telangiectasia patients without significant pulmonary right-to-left shunt at screening

Abstract

Objectives: To describe the incidence of pulmonary arteriovenous malformations (PAVM)-related complications, right-to-left shunt (RLS) progression at transthoracic contrast echocardiography (TTCE) and development of treatable PAVM during long-term follow-up in hereditary hemorrhagic telangiectasia (HHT) patients with RLS grades 0-1 at screening TTCE. Methods: Observational prospective study including adult HHT patients with grades 0-1 RLS at screening TTCE. Those requiring previous embolization of PAVM were excluded. PAVM-related complications and RLS progression during follow-up were recorded. Results: 183 patients were followed-up during 5.6 [IQR: 3.3-8.2] years. Seven (3.8 %) patients developed potentially PAVM-related complications, although all of them were considered unrelated to HHT after multidisciplinary assessment. Among 84 patients with a follow-up TTCE, RLS progressed to grades ≥2 in eight (9.5 %). Among patients with grade 0 RLS at screening, 31.6 % evolved to grade 1 RLS during follow-up and none progressed to grade ≥ 2. Among patients with grade 1 RLS at screening, RLS increased in 17.4 %, by one grade in most cases, and two (2.4 %) patients developed treatable PAVM. Grade 1 RLS and a higher epistaxis severity score were associated with RLS progression. Conclusions: In HHT patients with grades 0-1 RLS at screening, PAVM-related complications are rare. No patient with grade 0 RLS showed an increase in RLS of more than one grade on TTCE. Among patients with grade 1 RLS, rescreening every 5 years should be recommended because treatable PAVM can develop; follow-up with TTCE could be an alternative, as it would allow a better selection of patients for chest CT.