First data on cardiac mapping and outcome of pulmonary vein isolation using a novel ablation catheter with tip mini electrodes.

AIMS: Pulmonary vein isolation (PVI) is a standard treatment of atrial fibrillation (AF). AF recurrence after PVI occurs in a substantial number of cases. A novel ablation catheter equipped with mini-electrodes (ME) may facilitate PVI. Our study evaluated outcome after PVI with the ME catheter compared to a standard catheter. METHODS: Patients undergoing PVI with the ME catheter were compared to a control group ablated with a standard contact force sensing catheter. Freedom of AF after 12 months was the study endpoint. Additionally, low voltage areas (LVA) <0.5 mV were identified with a circular mapping catheter (CMC) and the ablation catheter in each group. LVA were compared between the maps obtained with the CMC and the ME or standard catheter, respectively. RESULTS: A total of 110 patients underwent PVI with ME catheter (n = 59) or the standard catheter (n = 51). Procedure duration (117.4 ±â€¯43 vs. 103.1 ±â€¯32.8 min, p = 0.15), radiation dose (1135.6 ±â€¯1125.7 vs. 1078.8 ±â€¯951.4 µGy/m2, p = 0.91), incidence of complications and 12-month success rate (64.4 vs 72.5%, p = 0.36) were not significantly different between the groups. LVA were significantly smaller when obtained with the standard catheter compared to the CMC (14 ±â€¯13 vs. 58.5 ±â€¯22.1 cm2, p < 0.001), while no such difference was seen for mapping with the ME compared to the CMC (37 ±â€¯30.3 vs. 33.4 ±â€¯39 cm2, p = 0.4). CONCLUSION: Clinical outcomes are comparable between ME catheter and a standard contact force sensing catheter. Furthermore, better LVA detection points to improved mapping capabilities of the ME catheter.

Cardiac mapping and pulmonary vein isolation using a novel ablation catheter with tip minielectrodes.

BACKGROUND: Pulmonary vein isolation (PVI) is a standard treatment for atrial fibrillation (AF). Identification of gaps in the ablation line is difficult. Tip-ring electrograms from ablation catheters represent relative large areas of myocardial tissue. Recently, an ablation catheter with three minielectrodes (ME) on the catheter tip with closer interelectrode spacing was introduced. The aim of our study was to evaluate the novel electrodes during PVI. METHODS: PVI was performed with an irrigated ablation catheter equipped with conventional electrodes and three additional radial tip electrodes. Detection of pulmonary vein potentials (PVPs), local signal amplitude, amplitude reduction during ablation, and loss of capture after ablation were compared between the ME and the conventional tip-ring electrodes. RESULTS: Thirty-one patients (mean age 67.8 ± 10.3 years, 45.2 % men) were included. A total of 306 mapping/lesion points were analyzed. A PVP was significantly more often obtained with the ME compared to the conventional tip-ring electrodes (99.2% vs 83.5%, P < 0.001). Local amplitude was significantly higher on the ME (0.8 ± 0.6 mV vs 0.67 ± 0.46 mV, P  =  0.003). Amplitude reduction during 1 RF pulse was significantly greater on the ME (82.9 ± 19.5% vs. 61.8 ± 26.9%, P < 0.001). During pace mapping, loss of capture after 1 RF pulse was observed significantly more often on ME (98.3% vs 63.3%, P < 0.001). CONCLUSION: Signal amplitude is higher and sensitivity during PVP mapping and ablation is increased when ME are used. ME may facilitate catheter ablation of AF in the future.