Stereotactic Body Radiotherapy for Noninvasive Arrhythmia Treatment

Atrial fibrillation (AF) is the most common cardiac arrhythmia clinically and a major risk factor for cardiogenic stroke, especially in the elderly, and also one of the factors leading to heart dysfunction.Conventional treatment methods for restoring sinus rhythm include synchronous electrical cardioversion, pharmacological cardioversion and radiofrequency ablation, which are effective but still limited due to treatment failures to control sinus rhythm and the side effects of long-term medication and the invasiveness of radiofrequency ablation.Ventricular tachycardia (VT) is a malignant arrhythmia, which is the most common cause of sudden cardiac death (SCD).Antiarrhythmic medications and endocardial catheter ablation remain as guidelinessupported VT treatment strategies for patients with structural cardiac abnormalities.Recent clinical results showed that more than half of patients had recurrent VT after catheter ablation, and for patients with intracardiac thrombosis, deep ablation sites, or mechanical valve replacement, catheter ablation is often not completed.The invasive and potential complications of radiofrequency ablation make it unattractive for patients with multiple complications or hemodynamic impairments.This paper describes the stereotactic body radiotherapy (SBRT) technique and its clinical potential for the noninvasive ablative treatment of AF and VT together with its important implications for future beneficial clinical applications.In vivo experimental studies that provided useful preclinical data are reviewed and the results of pioneering clinical trials will be discussed together with the dosimetric considerations and pros and cons of the treatment approach.