Anti-arrhythmic device therapy has limits in improving the prognosis of patients with cardiac amyloidosis

Immunoglobulin light chain (AL) amyloidosis has poor long-term prognosis. Sudden cardiac death (SCD) is a common cause of death in patients with cardiac AL amyloidosis. Prophylactic anti-arrhythmic device therapy has been suggested as an option to reduce this risk. We address this issue by reviewing 4 cases of cardiac AL amyloidosis with anti-arrhythmic device therapy. One patient who had an atrioventricular block underwent pacemaker implantation, and the other 3 patients received implantable cardioverter-defibrillator (ICD) implantation for ventricular arrhythmia. All of the 3 ICD implantation cases received appropriate shock therapy for ventricular arrhythmia in the early stage. However, they soon died due to pulseless electrical activity (PEA) or severe heart failure. The median survival period for our 4 cases was as short as 12.3 months. In particular, the 3 patients who required ICD had worse prognoses. Thus, ICD implantation therapy for chemotherapy-resistant cardiac AL amyloidosis may prevent SCD but may not prolong the patient's survival. There are no arguments against pacemaker implantation for cardiac amyloidosis with conduction disturbance; however, the clinical benefit of ICD indication for ventricular tachyarrhythmia is limited. Further extensive clinical research should be performed to definitively determine the effects of ICD implantation on cardiac AL amyloidosis.