In an international survey, 1025 respondents (median age 55 years) met HHT diagnostic criteria: 942 (91.9%) reported nosebleeds, 452 (44.1%) at least daily. AVMs were commonly reported in pulmonary (544, 53%), hepatic (194, 18.9%) and/or cerebral (92, 9.0%) circulations. 770/1025 (75%) had used iron tablets, 256 (25.0%) intravenous iron, and 374 (36.5%) received blood transfusions. Arrhythmias were reported by 113/1025 (11%, including 44 (4.3%) with atrial fibrillation), angina by 36 (3.5%), and cardiac failure by 26 (2.5%). In multivariate logistic regression, these phenotypes were associated with hepatic AVMs/pulmonary hypertension (relatively interchangeable variables), blood transfusions, and intravenous iron. Cardiac insufficiency/failure often provokes intensive anemia treatments, but associations with arrhythmias, particularly with a greater transfusion burden, were less easy to explain.
Myocardial infarction (23/1025; 2.2%), and abnormal coronary angiogram (≤ 31/76, ≤ 54%) rates appeared low. Provocative preliminary data were obtained including HHT-affected respondents' parents and grandparents in whom HHT could be confidently assigned, or excluded based on autosomal dominant inheritance patterns: in crude and survival analyses, myocardial infarctions were reported less frequently for individuals with HHT, particularly for males (p = 0.001).
Arrhythmias are the most common cardiac phenotype in HHT, and likely to be aggravated by iron deficiency anemia, its treatments, and/or high output states due to AVMs. Myocardial infarction rates may be reduced in this apparently high risk population.