Role of epicardial mapping catheter ablation of postmyocardial infarction ventricular tachycardia

The role of epicardial mapping for radiofrequency (RF) catheter ablation of postmyocardial infarction monomorphic ventricular tachycardia (VT) is still under investigation. We present two septuagenarian patients with a history of myocardial infarction, poor left ventricular function, and drug-refractory monomorphic VT who were treated with RF catheter ablation. The first patient had a history of myocardial infarction, left ventricular aneurysm, and mitral valve replacement complicated by recurrent drug refractory VT and congestive heart failure. The second patient had ischemic cardiomyopathy and VT and was implanted with a cardioverter defibrillator and subsequently suffered repeated episodes of VT refractory to multiple antiarrhythmic drugs. In both patients, coronary sinus mapping was performed with a multipolar catheter as endocardial mapping did not reveal satisfactory sites for ablation. Epicardial catheter mapping provided stable electrograms and identification of areas of slow conduction during VT. RF lesions guided by epicardial mapping resulted in successful ablation of VT and no recurrence at long-term follow-up. This report emphasizes the potential usefulness of coronary sinus mapping as an adjuvant to endocardial mapping to guide VT ablation.