Search

The Contact (St Jude Medical) System uses a novel impedance- based measure of Electrical Coupling Index (ECI) to assess the quality of catheter tip to endocardium contact. We sought to establish average ECI measurements and behaviour during pulmonary vein (PV) isolation procedures. Forty-five patients undergoing PV isolation for atrial fibrillation (AF) were studied.'Non-contact' and upper range 'in-contact' catheter positioning was performed for system calibration. ECI measurements were recorded pre-ablation at 14 standardized locations around the PV antra. The mean ECI non-contact value was 77 ± 11 (range 63-107); the mean upper range in-contact value was 111 ± 16 (range 81-145). Mean ECI values pre-ablation around the PV antra ranged from 85 ± 18 to 107 ± 19. A trend towards higher mean ECI values was noted with increasing body mass index (BMI). Pre-ablation mean ECI values were 92 ± 10 (BMI 20-25), 95 ± 12 (BMI 26-30) and 104 ± 11 (BMI >30) (p< 0.01 for 20-25 vs. >30). A positive correlation was noted for mean pre-ablation ECI values and BMI (r=0.50). An expected range of ECI values during PV isolation has been documented in this study. Observed ECI values correlate with patient BMI. The potential limitations of the current generation Contact System and scope for future clinical applications are discussed.

Inflammation has emerged as being strongly associated with AF initiation and perpetuation, including being implicated as a possible causal factor. Its role needs further elucidation to assist with the optimal prevention and treatment of AF using an individualized strategy. In the present review article the current published data linking inflammation to AF is summarized.

Background Patients with atrial fibrillation (AF) may be interested in undergoing concomitant interventions of left atrial catheter ablation and device occlusion of the left atrial appendage (LAA). We report on the feasibility and outcome of combined procedures in a single centre case series. Methods Twenty-six patients underwent either first time or redo pulmonary vein isolation (PVI) procedures followed by successful implant of a Watchman ® device. Results All procedures were uncomplicated with a mean case time of 233 ± 38 minutes. Maximal LAA orifice dimension was smaller in 3 of 26 patients post PVI (range 1mm) than on the pre-procedural transoesophageal echocardiogram (TOE). A new peri-device leak of maximum 3mm was noted in 5 of 26 patients at 6 week follow-up TOE, but resolved in 4 by the 6 month follow-up. Conclusion Combined procedures for catheter ablation for AF and Watchman ® LAA implant appear to be feasible and safe with satisfactory occlusion of the LAA maintained at follow-up.