High-Density Mapping in Ventricular Tachycardia Ablation: A PentaRay Study.

BACKGROUND

High-density mapping of ventricular tachycardia (VT) with PentaRay (Biosense-Webster) provides high resolution with discrimination of local abnormal electrograms and slow conducting channels. We evaluate the feasibility of PentaRay to characterize the anatomical substrate and assume an influence of the outcome despite limitations.

METHODS

Over a 24-month period, 26 endocardial and four epicardial maps were obtained of 26 VT patients (18 ischemic cardiomyopathy (ICM, 69.2%) and 8 non-ischemic cardiomyopathy (NICM, 30.8%), age 65 ± 9 years). Catheter ablation (CA) was performed with the aim of transecting the isthmus. The endpoint was non-inducibility of any VT. Manual review of the maps was performed and focused on evaluating scarring, bipolar electrograms, and procedure times.

RESULTS

In 55.6 ± 34.4 min, 1,085.9 ± 726.2 points were created. The mean ablation time was 50.8 ± 30.1 min. The endpoint was achieved in 12 patients (46.2%). The mean dense scar area and the mean patchy scar area were 49.4 ± 51.8 cm (range 0 - 190 cm) and 14.7 ± 14.9 cm (range 0 - 110 cm), respectively. Analyzing the learning curve, we found a tendency in decreasing procedure times. During the course of follow-up treatment averaging a 14-month period, device interrogation showed that 17 patients (65.4%) had remained free of any arrhythmia recurrence.

CONCLUSION

The high-density maps with PentaRay were safely created in a short period of time. Our manual review of the maps reveals limitations of current annotation criteria; nevertheless, medium-term outcomes were encouraging. Further prospective studies are required to validate our findings in a larger cohort of patients.