The association of diabetes, atrial fibrillation and ventricular arrhythmias

Recent evidence suggests that diabetic patients are at increased risk to develop arrhythmias. This brief review presents this evidence and the relationship between diabetes mellitus (DM) and arrhythmias, specifically atrial fibrillation (AF) and ventricular arrhythmias (VAs). Animal studies have demonstrated that hyperglycemia induces oxidative stress that results in myocardial injury and cell ischemia which predispose to AF. Furthermore, prolonged hyperglycemia results in the formation of advanced glycosylation end products which invade the myocardium and lead to diabetic cardiomyopathy forming a substrate for anatomic and electrical atrial remodeling predisposing to AF as well. Patients with DM and without known cardiovascular disease have significantly higher incidences of T-wave alternans (TWA) than non-DM patients. These TWA occurrences are positively correlated to HbA1c level. DM also produces a diabetic myocardium vulnerable to VAs and plays a crucial role in triggering these arrhythmias. In conclusion, further randomized controlled trials are needed to verify the mechanisms that result in arrhythmias in patients with DM and which lead to major cardiovascular complications and mortality.The focus of interventions should be based on primary prevention of diabetes, coronary artery disease, and atherosclerosis until novel mechanism-based approaches that reduce arrhythmias in patients with DM are established.