Prevalence of Cardiac Amyloidosis in Patients with Carpal Tunnel Syndrome Abstract Carpal tunnel syndrome (CTS) is a common finding among patients with cardiac amyloidosis. We sought to determine the prevalence of cardiac amyloidosis in patients who had undergone CTS surgery. From 2005 to 2014, 308 patients ≥ 60 years underwent CTS surgery. Of these, 233 (76%) agreed to participate in the study and 101 (73 ± 8 years; 68% females) showed left ventricular hypertrophy (LVH) ≥ 12 mm and underwent additional studies to diagnose AL and ATTR amyloidosis. Based on complementary studies, three patients were diagnosed with cardiac amyloidosis (two wild-type ATTR and one AL). The three patients showed bilateral CTS with no occupational risk factors. Prevalence of cardiac amyloidosis in the overall cohort was only 1.2% (3/233), but among patients with LVH and bilateral CTS, the prevalence was 5.5% (3/55) and 13.6% (3/22) if cases with an occupational risk factor were excluded. Cardiac amyloidosis should be excluded in the presence of bilateral CTS and particularly if an occupational risk factor is absent.