Clinical and laboratorial profile of patients with ATTR cardiomyopathy: comparison between wild type and p.Val142Ile forms in the Brazilian population

Abstract Background In Brazil, besides the wild type (wt) form, transthyretin amyloid cardiomyopathy (ATTR-CM) is predominantly caused by hereditary form with Val142Ile mutation. Considering that both forms occur in elderly people, the clinical presentation may be similar. We sought to compare the clinical presentation of patients with wt and Val142Ile mutation in a Brazilian cohort of ATTR-CM patients. Methods Among the 642 patients enrolled in REACT/SP, 283 presented ATTR-CM, being 85 wt and 90 Val142Ile patients. We compared the main clinical characteristics between groups. Results The wt in comparison to Val142Ile patients, respectively, presented: older age (78.4+/-8.5 vs 74.2+/-8.1 y.o., p = 0.0009); similar proportion of males (82% vs 81%, p=0.85); lower proportion of blacks (11% vs 39%, p=0.0001); similar prevalence of heart failure (HF) symptoms (85% vs 79%, p=0.33); higher prevalence of syncope (13% vs 2%, p=0.008) and Pacemakers (PM) implantation (8% vs 1%, p=0.027); similar prevalence of neuropathy manifestations (38% vs 51%, p=0.17); lower creatinine (1.5+/-0.8 vs 2.1+/-2.1 mg/dL, p=0.02) and NT-ProBNP levels (2860.0+/-2843.3 vs. 5488.3+/-5455.6 pg/ml, p=0.0001); reduced interventricular septal thickness (15.6+/-3.3 vs 17.0+/-3.3 mm, p= 0.006), posterior left ventricular (LV) posterior wall thickness (14.2+/-2.4 vs 16.2+/-4.4 mm, p=0.0003), higher LV ejection fraction (52.0+/-10.1 vs 48.2+/-13.6%, p=0.038), higher global LV longitudinal strain (8.6+/-8.7 vs 3.4+/-9.8, p=0.0003), smaller LV diastolic diameter (45.9+/-6.1 vs 43.0+/-7.3 mm, p=0.005) at 2D-Echocardiogram. Conclusions In the Brazilian population wt and Val142Ile patients had similar clinical presentation regarding HF and neuropathy symptoms, but higher prevalence of syncope and PM in wt patients. Conversely, Val142Ile patients presented more severe amyloid cardiac infiltration.