Loss of Late Potentials After Radiofrequency Catheter Ablation of Recurrent Ventricular Tachycardia in a Patient with Right Bundle Branch Block

The case of a patient with a history of myocardial infarction and recurrent ventricular tachycardia undergoing attempted radiofrequency catheter ahlation with loss of late potentials is described. Prior to energy delivery fractionated, late activation could be found using the signal-averaged ECC despite the presence of a right bundle branch block. After successful catheter ablation, the clinical ventricular tachycardia was no longer inducible and the signal-averaged ECG, recorded the next day, showed marked changes indicating loss of late potentials. Our report emphasizes the possibility of late potential recordings despite the presence of bundle branch block.