AF Ablation: How has the Technique and Technology developed? Professeur Dipen Shah Responsable de l’Unité d’électrophysiologie, Hopital Cantonal de Geneve, Geneve 7 th International Congress of Egyptian Cardiac Rhythm Association 15 th -17 th December 2010, Cairo

Architecture of the junction between pulmonary veins and the left atrium: lessons for radiofrequency ablation 25 year Male Right Left 60y Male 80y Female Left upper Ho SY et al, Heart 2001 Isthmus between veins at veno-atrial junction Left upper Left lower Common vein

PV Ablation Options Sequential point by point ablation Simple Individual optimisation of lesion delivery possible Obligatorily time consuming Finite irreducible rate of gap occurrence Circular lesion making devices Unfamiliar, more complex design Difficult to optimise contact/to generate consistent lesions Still do not achieve rapid, one-shot isolation

Zheng et al, Journal of Interventional Cardiac Electrophysiology 5, 401–410, 2001

Linear Ablation Technologies PV ablation times: segmental PVI: min Hocini et al. and CPVA: min Oral et al. PVAC: Boersma et al min, & Scharf et al min

Multi-electrode PVAC Incomplete circular form resulting in suboptimal circular mapping Combination of bipolar and unipolar RF difficult to titrate Noise does not allow electrogram monitoring during RF Uniform contact essential for bipolar RF efficacy but unknown No irrigation: uncertain protection from char/coagulum Ablation times similar to segmental PVI: no single shot ablation

Cryoballoon Ablation Pre-Cryo Post-Cryo LSPV Location of conduction recovery at redo Image courtesy V. Reddy

Cryo-Balloon Cryo-ablation in circulating blood: time consuming and probably smaller lesions PV anatomy oval not circular: single-shot ablation not frequent Inferior PVs difficult to isolate Significant risk of phrenic palsy No immunity from esophageal damage Pacing Catheter in SVC Cryoballoon Catheter at RSPV ostium Image courtesy V. Reddy

Visually-Guided Ablation Aiming Beam “Static” Blood in LSPV LIPV LAA

In Vivo Visually-Guided A.Flutter Ablation V.Reddy / P.Neuzil (manuscript in preparation)

Contact Sensing Contact Force (g) Incidence of Steam Pop (%) /10 5/10 6/10 7/10 8/10 50W p = /10 3/10 30W p =0.031 (%) Yokoyama K, Nakagawa H, Shah D et al Circ Arrhythmia EP 2008

12% Source: K-H Kuck, presentation Boston AF % of ablations done with low contact forces (< 5 g) 0% 5% 10% 15% 20% 25% 30% 35% %age of ablations done with contact force < 5g 12% RIGHT PVs Septal Sup. Septal Inf. RoofMiddleInferior Post. Sup. Post. Inf. Low forces 15%12%3%13%23%12%11% LEFT PVs Post. Sup.Post. Inf.RoofMiddleInferiorAnt. Sup.Ant. Inf. 8%4%7%23%7%21%32%

Sheath assisted Perforation RV * * LV w/o sheath with sheath w/o sheath with sheath Peak Df/dt: LV perforation LV perforation time: 0.8±0.5s with sheath vs 3.2±3 s w/o, p< grams time 736 ± 368 g/sec 239± 178 g/sec p = Shah D et al, Europace 2010

Perforating Force thru’ RF lesions 172±79g 300±116g p<0.002 n= 23n= 21 Shah D et al, Europace 2010

Remote Navigation Systems Magnetic Navigation: Fixed Magnets (Stereotaxis) Magnetic Navigation: Electro-Magnets (Magnetecs) Robotic Navigation (Hansen Medical) Fixed Magnetic Nav Robotic Nav Electro-Magnetic Nav

Arya et al, Europace 2010 e-pub

robotic arm Sensei™ Robotic Catheter System 3D mouse

Electromechanic Navigation 34 of 40 pts off anti-arrhythmic drugs and „free from atrial arrhythmia“ 85% 5 pts still on anti-arrhythmic medication 2 pts with perforations/tamponade Atrial fibrillation ablation Saliba et al. JACC Vol. 51, No. 25, 2008:2407–11 Wazni et al, JCE patients undergoing PV antral isolation 5 vascular complications 3 tamponade 5 severe PV stenosis 1 gastroparesis 4/4 pts with esophageal ulceration at endoscopy on the post-ablation day 1/4 pts developed esophageal fistula formation necessitating stenting Kuck KH, EHRA-Webinar AF ablation, March 2009

Electro-mechanical Navigation Point by point mapping and ablation: no reduction in procedure time Extra –stiff sheath and poor contact force monitoring: higher risk of traumatic perforation and other complications Single catheter control only AF ablation poorly suited to automated, fully robotic procedure

Technology for AF Ablation New technology should simplify ablation Shorten the procedure by reducing ablation times Provide rapid and reliable endpoint verification Result in durable, non- proarrhythmic lines of isolation Should not increase complication risks Current standard of reference…