Afro-Caribbean regions might have a high prevalence of transthyretin cardiac amyloidosis due to their shared ancestry with Afro-American populations, where a high prevalence of Val122Ile variant of the transthyretin gene has been found. Val122Ile variant is associated with late onset cardiac amyloidosis. Still, the prevalence of cardiac amyloidosis disease (CAM) inpatients presenting with unexplained left ventricular hypertrophy (LVH) in these settings is not known. The aim of this study was to determine the prevalence of cardiac amyloidosis in a consecutive cohort of patients with unexplained left ventricular hypertrophy.

Three centres in Fort de France, Trinité (Martinique) and Basse-Terre (Guadeloupe) participated. Patients were consecutively enrolled if they have wall thickness>15mm at echocardiography. The first diagnosis line was based on findings of an abnormal cardiac fixation of bone tracer and/or a monoclonal gammapathy. Patients with such abnormalities were then referred for a more complete set of procedures including gingival or cardiac biopsies, MRI, and transthyretin gene sequencing.

We present here the preliminary results of the first 127 patients enrolled. Mean age was 65±11 years. Mean septal thickness was 16.2±2.3mm and posterior wall 14.6±2.1mm. Diagnosis was accurate in all but 9 patients. Cardiac amyloidosis was found in 40 patients (33.9%), including 34 with transthyretin cardiac amyloidosis (CATTR) and 6 patients with AL amyloidosis. Male gender was found in 25/34 (78%) patients with CATTR.

Transthyretin cardiac amyloidosis is very frequently observed inpatients with unexplained left ventricular hypertrophy in The French Caribbean's.