Technological advances in implanted dual-chamber cardioverter defibrillator (ICD) or cardiac resynchronization therapy defibrillator (CRT-D) devices allow early detection and real time verification of AF/AFL with intracardiac electrograms (IEGM) automatically transmitted to the clinicians. Such remote diagnostic capability might be particularly relevant in patients with asymptomatic AF by allowing timely treatment. Compared to conventional periodic, (e.g., quarterly) office device evaluation, daily remote monitoring may prove superior for diagnosis of AF and prophylactic treatment of thromboembolism.