Predictive Value of Right Ventricular Sensing During Cardiac Device Implantation to Diagnose Cardiac Amyloidosis.

Background: Cardiac amyloidosis (CA) is an underdiagnosed disease, often presenting with electrical conduction abnormalities or ventricular arrhythmias, prompting implantation of cardiac implantable electrical devices (CIEDs).

Objectives: This study sought to evaluate the performance of right ventricular sensing (RVSens) during implantation of CIEDs in patients presenting with increased left ventricular (LV) wall thicknesses (ILVWT) and preserved LV function to predict the diagnosis of CA.

Methods: All consecutive patients with ILVWT (maximal LV wall thickness ≥12 mm), preserved LV function and no significant aortic stenosis who underwent implantation of CIEDs at 2 French referral centers for rare and inheritable cardiac diseases were retrospectively evaluated. Clinical history, imaging, biological data, histologic data, and pacing lead parameters at the time of implantation were collected. Diagnostic categorization of ILVWT (CA, sarcomeric hypertrophic cardiomyopathy, or hypertensive heart disease) was determined according to guidelines.

Results: We included 218 patients with ILVWT, of which 150 had CA and 68 had sarcomeric hypertrophic cardiomyopathy or hypertensive heart disease. Ten patients (4.6%) had their device implanted before ILVWT diagnosis, 131 (60.1%) had their device implanted during the same hospitalization, and 77 (35.3%) in a subsequent hospitalization. An RVSens ≤11 mV was independently associated with CA diagnosis with a sensitivity of 84% and a specificity of 79.4% (AUC: 0.878).

Conclusions: In patients with ILVWT, a relatively low RVSens (≤11 mV) during device implantation was independently associated with CA diagnosis, prompting further evaluation to rule out CA if the diagnosis is uncertain.