Atrial fibrillation (AF) and ventricular tachycardia (VT) affect millions of patients in the United States. These arrhythmias can be cured with catheter ablation, but arrhythmias often recur, and these recurrences are generally due to reversible conduction block from incomplete ablation. The inability to confirm the presence of completely ablated lesions in the desired locations is the major factor in the greater than 40% recurrence of VT after ablation and the greater than 30 % recurrence of AF after ablation. In addition, it is not possible with current technology to adequately predict the pathways of VT through scar, which are the targets for ablation.
Dr. Halperin’s team has been studying the use of advanced, image-based technologies to improve targeting and assessment of electrophysiology intervention. The needed technology has been developed, the clinical system has been defined, and the feasibility of the approach has been demonstrated.
We have shown that high-resolution Magnetic Resonance Imaging (MRI) with compatible electrode catheters, location sensors, mapping systems, real-time scanner control, and computational modeling, can (1) aid in predicting the locations of arrhythmia circuits (2) aid in predicting the locations of critical ablation targets, (3) provide for accurate catheter navigation to those critical targets, (4) monitor the formation of ablation lesions in real-time, and (5) assess the completeness of ablation. Once validated, these enhanced capabilities could dramatically improve the outcomes from complex ablation procedures, become the ablation methodology of the future, and become a platform for improving outcomes from many other interventions.
In the current program, we developed important, innovative methods, and MRI-compatible versions of ablation equipment, for predicting VT ablation targets, for performing ablations in an MRI scanner, and for lesion imaging. We developed imaging methods that differentiate incompletely ablated (reversibly damaged) tissue from completely ablated (necrotic) tissue. This allows determination of whether there is complete lesion necrosis, or whether additional ablation is needed during the procedure to complete the ablation.