E. Baldo

Radiofrequency Ablation of Atrial Fibrillation Is the Persistence of All Intraprocedural Targets Necessary for Long-Term Maintenance of Sinus Rhythm?

Background— Several approaches have been developed for radiofrequency catheter ablation of atrial fibrillation, but the correct intraprocedural end point is still under debate, and few data exist about the destiny of ablation lesions over time. The aim of the present study was to evaluate the long-term maintenance of intraprocedural end points of ablation procedures. Methods and Results— Inclusion criteria were (1) a previous ablation procedure of pulmonary vein (PV) encircling performed for drug-refractory persistent atrial fibrillation; (2) a “complete” intraprocedural end point, which consisted of voltage abatement inside the lesions, PV disconnection, and exit-block pacing from inside the lesions, attained in all PVs; and (3) stable sinus rhythm documented during a minimum follow-up of 2.5 years after the procedure. Twenty volunteers were selected (12 males, mean age 59±7 years) and underwent a repeat electrophysiological study. After a follow-up of 36.4±4.7 months, complete voltage abatement was maintained around 32 PVs (40.0%), PV disconnection persisted in 12 (37.5%) of the previously isolated PVs, and exit block was present in 39 PVs (48.7%). Ten patients who underwent a redo ablation procedure because of recurrences of atrial fibrillation were used as the control group. Differences in intraprocedural end-point maintenance between the 2 groups were not statistically significant. Conclusions— Common intraprocedural end points such as voltage abatement, PV disconnection, and exit block persist only in a limited number of patients, even when the outcome is favorable during follow-up. Further investigation will be required to determine whether such data will have implications for ablation strategies.

Feasibility of the transseptal approach for fast and unstable left ventricular tachycardia mapping and ablation with a non-contact mapping system

BackgroundRadiofrequency ablation of fast and unstable left ventricular tachycardia (VT) usually requires non-contact mapping. The procedure is usually performed by a retrograde-transaortic route, requiring a double femoral artery puncture, for the 9F multielectrode catheter and the 7F ablation catheter which are advanced through the aorta and aortic valve into the left ventricle (LV). Reported limitations of the procedure are due to the stiffness of the balloon catheter, particularly in patients with tortuous peripheral arteries, atherosclerotic aorta, or with aortic stenosis. The aim of our study was to test the feasibility and assess the safety of a transseptal approach for left VT non-contact mapping and ablation.Materials and methodsTen patients with multiple cardiac defibrillator shocks because of fast and unstable VT were selected for non-contact mapping and ablation. After a double transseptal puncture the multielectrode catheter (Ensite Array™, St. Jude Medical) was advanced through a standard 10F introducer to a stable position in the LV apex over a 260xa0cm length 0.035 J-tip guidewire. The ablation catheter (Celsius™ Thermo-cool, Biosense Webster) was then inserted through the second 8F introducer. Twenty-five monomorphic sustained ventricular tachycardia were induced and ablated at the level of the diastolic pathway or exit point revealed by unipolar isopotential mapping. The total procedural and fluoroscopy times were 209 ± 32xa0min and 28.5u2009±u20099.27xa0min, respectively, which were comparable to those described with the traditional retrograde-transaortic approach. No major complication related with the transseptal approach were reported.ConclusionA transseptal approach can be a feasible and effective alternative approach for mapping and ablation of fast and unstable left VT with a non-contact mapping system.

Radiofrequency atrial fibrillation ablation based on pathophysiology: a diversified protocol with long-term follow-up.

Background The optimal approach and long-term results of radiofrequency catheter ablation of atrial fibrillation (AF) are still unknown. We report our experience with respect to an ablation protocol diversified on a patients AF pathophysiology with long-term follow-up. Methods Seventy-two patients with paroxysmal/persistent drug-resistant AF were selected. Patients with apparently normal hearts (group 1, n = 20) underwent electrophysiological disconnection of pulmonary veins (PVs) presenting a clear PV potential, whereas those with even initial cardiopathy (group 2, n = 52), underwent PV encircling. Results Sinus rhythm was maintained at 6 months in 85% of group 1 and 71% of group 2 patients. After 42 months of follow-up, including 15.2% re-do procedures, 85% of group 1 and 77% of group 2 patients were in sinus rhythm, including patients with anti-arrhythmic drugs (AADs). The long-term success rate without AADs was 75% and 46% for each group, respectively. Age and the 6-month success of the procedure were predictive of sinus rhythm maintenance during follow-up. Conclusions An ablation protocol diversified on AF pathophysiology assured, at 3 years of follow-up, sinus rhythm maintenance in 85% of patients with a normal heart and in 77% of those with even initial cardiopathy. The 6-month result of the ablation procedure remained stable over time.

8. Different Mapping Systems and Approaches for Ablation of Atrial Fibrillation8.1 A ‘Complete’ Mapping System for Atrial Fibrillation Ablation

Radiofrequency ablation is an established therapeutic option for drug resistant atrial fibrillation. It is also becoming clear that it is necessary to use different approaches in different clinical situations, and often we have to adapt the technique to the patient characteristics.nnThe electrophysiological approach can be performed with a multipolar pulmonary vein catheter with or without a mapping system whereas the anatomical approach requires a mapping system, for linear lesion creation and block confirmation.nnThe ENSITE System (St.Jude Medical) recently acquired in our EP Lab is a “complete” system. It can be used as a contact mapping system for electroanatomical approach, and for activation map creation; it can be also used as a non contact system for fast linear lesion validation, identification and abolition of lesion gaps. The possibility of obtaining immediate non contact activation maps is a great advantage to reach higher success rates and to reduce procedural times.nnIn Ferrara Ep lab we select the procedure on the target (trigger or atrial substrate) and thanks to flexibility of the Ensite system we can choose the best approach.

A ‘Complete’ Mapping System for Atrial Fibrillation Ablation

Radiofrequency ablation is an established therapeutic option for drug resistant atrial fibrillation. It is also becoming clear that it is necessary to use different approaches in different clinical situations, and often we have to adapt the technique to the patient characteristics.nnThe electrophysiological approach can be performed with a multipolar pulmonary vein catheter with or without a mapping system whereas the anatomical approach requires a mapping system, for linear lesion creation and block confirmation.nnThe ENSITE System (St.Jude Medical) recently acquired in our EP Lab is a “complete” system. It can be used as a contact mapping system for electroanatomical approach, and for activation map creation; it can be also used as a non contact system for fast linear lesion validation, identification and abolition of lesion gaps. The possibility of obtaining immediate non contact activation maps is a great advantage to reach higher success rates and to reduce procedural times.nnIn Ferrara Ep lab we select the procedure on the target (trigger or atrial substrate) and thanks to flexibility of the Ensite system we can choose the best approach.

8. Different Mapping Systems and Approaches for Ablation of Atrial Fibrillation

Radiofrequency ablation is an established therapeutic option for drug resistant atrial fibrillation. It is also becoming clear that it is necessary to use different approaches in different clinical situations, and often we have to adapt the technique to the patient characteristics.nnThe electrophysiological approach can be performed with a multipolar pulmonary vein catheter with or without a mapping system whereas the anatomical approach requires a mapping system, for linear lesion creation and block confirmation.nnThe ENSITE System (St.Jude Medical) recently acquired in our EP Lab is a “complete” system. It can be used as a contact mapping system for electroanatomical approach, and for activation map creation; it can be also used as a non contact system for fast linear lesion validation, identification and abolition of lesion gaps. The possibility of obtaining immediate non contact activation maps is a great advantage to reach higher success rates and to reduce procedural times.nnIn Ferrara Ep lab we select the procedure on the target (trigger or atrial substrate) and thanks to flexibility of the Ensite system we can choose the best approach.