Initial impedance decrease as an indicator of good catheter contact: Insights from radiofrequency ablation with force sensing catheters

Unipolar Electrogram Morphology to Assess Lesion Formation During Catheter Ablation of Atrial Fibrillation

“…21,22 In the study by Bortone et al, 18 the control group had RF ablation performed for an empirical 30 seconds at each site without any feedback on electrogram abatement or impedance changes, presumably without adjustment of the catheter to improve contact. In fact mean impedance change was identical in the unipolar ablation and the control group, which is hard to explain because catheter adjustments made in the study group should have resulted in better contact and a higher average impedance decrease.…”

Contact force and impedance decrease during ablation depends on catheter location and orientation: insights from pulmonary vein isolation using a contact force-sensing catheter

“…Recently, contact force-sensing (CF) catheters (SmartTouch, Biosense Webster, Diamond Bar, USA; Tacticath, St Jude Medical, Minneapolis, USA) have been developed, enabling the operator to visualize contact information from the distal tip of the catheter. Several studies have been published, investigating the impact of contact force on acute and procedural variables [2,3], on biophysical parameters [4][5][6][7][8][9] and on outcome after pulmonary vein isolation (PVI) [10][11][12]. However, contact force is only an essential but not sufficient criterion to describe the amount of energy transferred between catheter tip and the tissue.…”

Predictive Factors for Efficacy of Catheterbased Renal Denervation with Standard Ablation Catheter in Refractory Hypertension

“…Early study revealed the relationship between the initial impedance change and tissue heating, and indicated that an initial fall in impedance beyond 10 ohms would predict interruption of accessory pathways' conduction [20]. Until now, impedance decrease has even been an indicator of good catheter contact as evidenced by force sensing catheterization technique [21]. Our study results showed the correlation between impedance fall and reduction of blood pressure.…”