Prognostic significance of unexplained left ventricular hypertrophy in patients undergoing carpal tunnel surgery

Aims: Carpal tunnel (CT) syndrome is a recognized red-flag of cardiac amyloidosis (CA) and increased cardiovascular (CV) morbidity. We designed this study to characterize the CV profile of patients with CT syndrome at the time of first surgery and to identify high-risk presentations. Methods and results: We retrospectively reviewed 643 patients who underwent CT surgery between 2007 and 2019. Of them, 130 patients (77 years, 45% male patients, left ventricular ejection fraction 62%) with available CV characterization within ±12 months from CT surgery were included. Abnormal loading conditions causing cardiac left ventricular hypertrophy (LVH) were investigated to distinguish explained LVH (Ex-LVH) from unexplained LVH (Un-LVH). LVH was found in 66 (51%) patients, 33% of them presented Un-LVH. Compared with the others, Un-LVH patients were older (77 and 75 vs. 70 years in Un-LVH, Ex-LVH, and non-LVH, respectively; P = 0.002), had higher rates of electrocardiogram-echo discrepancy (70%, 14.3%, and 1.6%, respectively; P < 0.001) and of echocardiographic findings of CA (24%, 7%, and 0%, P < 0.001). Among Un-LVH patients, 9 (43%) experienced death and 7 (33%) developed heart failure (HF) at 3.8 and 2.4 years from CT surgery, respectively. Compared with the others, death and HF development rates were higher in Un-LVH patients both at unadjusted (P = 0.01 and P = 0.02, respectively) and adjusted analysis for age, gender, and renal insufficiency (P = 0.00038 and P = 0.050, respectively). Conclusions: At the time of CT surgery, Un-LVH was found in more than 30% of patients with LVH, and 24% of them showed echocardiographic features suggesting an underdiagnosed CA. Un-LVH was associated with higher all-cause mortality and HF development.