Electrophysiological Manifestations of Cardiac Amyloidosis

Cardiac amyloidosis (CA) is an infiltrative cardiomyopathy caused by the extracellular deposition of amyloid fibrils in the myocardium. Although cardiac amyloidosis patients primarily present with heart failure symptoms, arrhythmias and conduction system disease are frequently encountered. Atrial fibrillation (AF) is observed in up to 70% of patients at the time of diagnosis, and patients typically have controlled ventricular rates caused by concomitant conduction system disease. Thromboembolic risk is particularly high in patients with CA and AF, and left atrial thrombi have been observed even in the absence of clinically diagnosed AF. Atrioventricular nodal and infra-Hisian disease are common, and permanent pacemakers are frequently required. The use of implantable cardioverter-defibrillators in this population is controversial. This review summarizes the published data and therapeutic strategies surrounding arrhythmias and conduction system disease with the goal of aiding clinicians managing the clinical complexities of CA.