Atrial Epicardial Pacing with Long Stimulus to P Wave Interval in a Patient with Arrhythmogenic Right Ventricular Dysplasia Complicated by Right Atrial Thrombosis

Atrial epicardial pacing with a long stimulus to P wave interval in a patient with arrhythmogenic right ventricular dysplasia complicated by right atrial thrombosis is discussed. Arrhythmogenic right ventricular dysplasia (ARVD) is associated with a high incidence of malignant ventricular arrhythmias. Most patients with ARVD need antiarrhythmic drugs, catheter ablation, or an implantable cardioverter defibrillator. We report a patient with ARVD in whom effective treatment with sotalol caused severe, symptomatic sinus bradycardia requiring permanent pacing. Due to leftward displacement of the right ventricle and the presence of two thrombi in the right atrium, an epicardial atrial lead and AAI pacemaker were implanted. A long stimulus to P wave interval caused by severe dilatation of the right atrium was recorded. During a 6 months of follow-up on sotalol treatment there were neither ventricular tachycardia (VT) attacks nor pacing problems.