Matjaž Šinkovec

Long-term outcomes after radiofrequency catheter ablation of paroxysmal and persistent atrial fibrillation

Background : Short-term oucomes of radiofrequency (RF) catheter isolation of the pulmonary veins (PVs) in patients with paroxysmal or persistent atrial fibrillation (PAF/PEAF) are encouraging. However, long-term outcomes are not well defined. Therefore, we evaluated 3–5-year outcomes in our series of patients. Freedom from symptomatic AF/flutter/tachycardia recurrences with patients off antiarrhythmic drugs (AAD) was considered a treatment success. Methods : Consecutive patients with symptomatic PAF/PEAF and AAD failure, without significant structural heart disease, were prospectively recruited between September 2003 and November 2009. Irrigated-tip RF ablation catheter and Lasso catheter were used after standard trans-septal approach with X-ray fluoroscopic guidance. Ablation endpoints were: complete segmental/circumferential ostial and antral electrical PV isolation, non-PV foci ablation, and bi-directional flutter isthmus (FI) block when indicated. The procedure was repeated if AF/flutter/tachycardia recurred after 3-month blanking period. The suspected arrhythmia recurrences were evaluated by series of ECG/Holter recordings. Data were analyzed by t-, chi-square, and Fisher’s exact tests. P < 0.05 was considered statistically significant. Results : In 126 patients, median age 55 years (range 19–75), 94 men (75 %), 86 with PAF and 40 with PEAF (31 %), 207 procedures were performed: single in 63 (50 %), double in 48 (38 %), and multiple in 15. FI was ablated in 53 patients (42 %). Tamponade occurred in 4 (3 %). No PV stenosis, esophageal injury, or stroke were detected clinically in 115 patients (91 %) during 36-month (13–89) follow-up. We achieved treatment success in 69 patients (61 %), partial success with a significant reduction of AF/flutter/tachycardia recurrences on AAD in 13 patients (12 %), and in 33 patients (27 %) the procedure was not successful. Overall, 73 % of our patients had long-term benefit. Outcomes were better in patients with PAF vs. PEAF (84 % vs. 48 %, p < 0,001), in younger age, in those without concomitant diseases, and in those with normal PV anatomy. These results were maintained in the subgroup of 58 patients over 56 months of follow-up: 35 (60 %), 6 (11 %), and 17 (29 %), respectively. Conclusions : Lasso-guided RF irrigated-tip segmental/circumferential PV isolation is a safe and long-term successful treatment of PAF in the majority of our patients. The method needs improvements in patients with PEAF, possibly with the introduction of new technologies.

Electrophysiological and clinical characteristics of atrioventricular nodal reentrant tachycardia and longterm success of radiofrequency catheter ablation

Background: Diff erent reentry circuits within A-V node region are able to sustain A-V nodal reentrant tachycardia (AVNRT). On this basis, electrophysiological criteria for at least three AVNRT types – slow/fast, fast/slow, and slow/ slow–have been proposed. Th e aim was to reevaluate these criteria in a group of our patients. In addition, clinical profi le and long-term success rate of catheter ablation procedure were studied. Methods: All consecutive patients referred for catheter ablation of AVNRT from September 2004 to December 2006 were prospectively recruited. Th e informed consent was signed by all and the study had been approved by the competent state’s ethics committee. A standard electrophysiological study with programmed single or double extrastimuli or high-rate electrostimulation until the development of refractoriness or tachycardia induction was performed. Orciprenaline i.v. was used to facilitate AVNRT induction and to test the ablation result. Slow-pathway electrograms at inferoposteroseptal right atrium and ablation-induced nodal rhythm were ablation targets. Th e radiofrequency energy of 30–50 W for a duration of at least 20 seconds was used. Non-inducibility of AVNRT and of echo-beats was the procedure end point. In addition, antegrade and retrograde A-V junction conduction times were measured and analysed manually. Patients underwent a detailed re-evaluation aft er at least 1 year of follow-up. Th e descriptive statistic was used to present the data. Results: One hundred and four patients, 72 % female, mean age 53 years, were included. Th ey had their fi rst tachycardia episode at a mean age of 35 years with an average recurrence rate of 1- to 3-times a year. Syncope was experienced in 9.5 % of patients. Familial tachycardias were reported in 4 % of patients. One third (34 %) were hypertensive (≥ 140/90 mmHg). In majority, slow/fast AVNRT type (98/104–94 %) was induced. Th e fast/slow and slow/slow types were rare (3/104 each). Th e mean heart rate of induced AVNRT was 166 beats/min. Measurements were available for 92 patients. Our best diagnostic criteria were: V-A’interval ( 150 fast/slow, 70–120 slow/slow), H-A’interval ( 200 fast/slow; 120–170 slow/ slow), and A’-H/H-A’ ratio (> 2,3 slow/fast, < 1 fast/slow, 1–2,3 slow/slow). Th e slow/fast type was generally induced from the atrium, while the fast/slow and slow/slow also from the ventricle. In the slow/fast type, the earliest retrograde atrial activation was recorded from the His bundle position in 95 % (proximal coronary sinus (CS) in 5 %). Th e earliest retrograde atrial activation was recorded from proximal CS in the fast/slow type, but from CS or His in the slow/slow. A transient A-V block was documented in 6 patients during ablation procedure. None of them needed a permanent pacemaker implantation. Aft er 16 months of follow-up, 96 % of our patients were free of tachycardia recurrences. Conclusions: Electophysiologic criteria for three AVNRT types, clinical characteristics, and AVNRT long-term radiofrequency catheter ablation success rate are consistent with data reported in the literature.

Follow-Up after lasso-guided irrigated tip radiofrequency catheter ablation in paroxysmal and persistent atrial fibrillation

aims We evaluated clinical outcome of segmental/circumferential pulmonary vein (PV) isolation and linear defragmentation procedure in our first series of patients with paroxysmal or persistent atrial fibrillation (PAF/PEAF). The freedom from symptomatic AF/flutter/ tachycardia recurrences with patients off antiarrhythmic treatment (AAD) was primary endpoint of the procedure. methods Consecutive patients with highly symptomatic PAF/PEAF and AAD failure were prospectively recruited from September 2003 to June 2007. Patients 40 % and left atrial diameter 3 months. In patients with PEAF, fast fragmented/complex electrograms were ablated in a linear fashion, connecting upper PV ostia and/or PV ostia with proximal anatomical structures. Only FI line was tested for completeness of block. The irrigated-tip radiofrequency ablation catheter and Lasso catheter (Biosense-Webster) were used after standard transseptal approach with X-ray fluoroscopy guidance. The suspected arrhythmia recurrences were evaluated by series of ECG/Holter recordings. Results. Fifty-eight patients, 43 men, average age 50 years, range 19–69, including 24(41 %) with PEAF, were enrolled. In these patients, 113 procedures were performed: single study in 20, 2 in 24, 3 in 11, and 4 in 3 patients, respectively. Complications occurred in 5 patients including tamponade in 2, acute effusion in 1, and inadvertened pericardial punction in 2. No PV stenosis, esophageal injury, or stroke were detected clinically during 16-month (4–47) follow-up. We achieved primary endpoint in 42 patients (72 %); partial endpoint in 5 patients (9 %) with significant reduction of AF/flutter/tachycardia recurrences on AAD; and in 11 patients (19 %) procedure was not successful. Overall, 81 % of our patients (93 % with PAF, 63 % with PEAF) benefited from the procedure. conclusions Lasso-guided irrigated-tip RF PV isolation and linear defragmentation is safe and long-term successful treatment of PAF/PEAF in majority of middle-aged patients.