Diabetes and arrhythmias
Cardiac arrhythmias are more common in subjects with diabetes mellitus (DM) than in their counterparts without diabetes. Atrial fibrillation (AF) is present in 10–20% of the DM patients, but the association between DM and AF is mostly due to co-morbidities of DM patients increasing the vulnerability to AF. When type 2 DM and AF coexist, there is a substantially higher risk of cardiovascular mortality, stroke, and heart failure, which indicates screening of AF in selected patients with DM. Anticoagulant therapy either with vitamin K antagonists or non-vitamin K antagonist oral anticoagulants is recommended for DM patients with either paroxysmal or permanent AF, if not contraindicated. Palpitations, premature ventricular beats, and non-sustained ventricular tachycardia are common in patients with DM. The diagnostic work-up and treatment of these arrhythmias does not differ between the patients with or without DM. The diagnosis and treatment of sustained ventricular tachycardia, either monomorphic or polymorphic ventricular tachycardia, or resuscitated ventricular fibrillation is also similar between the patients with or without DM. The risk of sudden cardiac death is higher in DM patients with or without a diagnosed structural heart disease. Patients with diabetes and a left ventricular ejection fraction less than 30–35% should be treated with a prophylactic implantable cardioverter defibrillator according to current guidelines. Beta-blocking therapy is recommended for DM patients with left ventricular dysfunction or heart failure to prevent sudden cardiac death due to arrhythmia.