Chronic inflammation due to autoimmune diseases is associated with a higher rate of supraventricular and ventricular arrhythmias leading to an increased risk for cardiovascular morbidity and mortality. Involvement of the cardiac conduction system is common in patients with chronic autoimmune diseases, although the penetrance of clinical signs and symptoms is variable and complete heart block with need for therapy is rare. The combination of the increased prevalence of structural cardiovascular disease and the direct impact of inflammatory mechanisms on cardiac electrophysiology seems to be responsible for the higher rate of tachyarrhythmias. In particular, fibroblast activation, gap junction impairment via changes in connexin composition and abnormalities in intracellular calcium-handling are mentioned. Electrocardiographic markers of an increased arrhythmogenic potential in patients with chronic autoimmune disorders may include prolonged P‑wave duration as well as abnormal QTc interval and reduced heart rate variability. Thus, minimizing the inflammatory burden through tight control of disease activity may help reduce the arrhythmic load.
Keywords: Atrial fibrillation; Cardiac electrophysiology; Cardiovascular mortality; Inflammation; Sudden cardiac death.