Letter by Minutoli et al Regarding Article, “Reduced Myocardial 123-Iodine Meta-Iodobenzylguanidine Uptake: A Prognostic Marker in Familial Amyloid Polyneuropathy”

Abstract

We read with great interest the study of Azevedo Coutinho et al1 evaluating the prognostic value of 123Iodine Meta-iodobenzylguanidine (123I-MIBG) scintigraphy in patients with transthyretin (TTR) familial amyloid polyneuropathy (FAP). The authors evaluated 143 patients with TTR-FAP comparing time to all-cause death with late heart-to-mediastinum MIBG uptake ratio (H/M). Median follow-up was 5.5 years. Of 143 patients, 32 (22%) patients died. Five-year mortality rate was 42% and 7.4% for patients with late H/M <1.60 (the estimated lower limit of normal) and H/M ≥1.60, respectively, reaching a high statistical significance (hazard ratio, 7.19; P <0.001). Late …