Percutaneous catheter cryothermal ablation of atrioventricular nodal reentrant tachycardia: efficacy and safety of a new ablation technique (original) (raw)
Related papers
Cryoablation: how to improve results in atrioventricular nodal reentrant tachycardia ablation?
Europace, 2010
Ablation for atrioventricular nodal reentry tachycardia is very effective, with a potential for damage to the normal conduction system. Cryoablation is an alternative, as it allows cryomapping, which permits assessment of slow pathway elimination at innocent freezing temperatures, avoiding permanent damage to the normal conduction system. It is associated with shorter radiation times and the absence of heart block in all published data. We discuss in this overview different approaches of cryoenergy delivery (focusing on spot catheter ablation), and how lesion formation is influenced by catheter tip size, application duration, and freezing rate. Some advantages of cryoenergy are explained. Whether these features also apply for an approach with a cryoballoon, e.g. for atrial fibrillation is unclear.
Europace, 2009
To compare recurrence rate and other procedural characteristics in patients undergoing atrioventricular nodal re-entrant tachycardia (AVNRT) treatment with catheter cryoablation (CRYO) delivered by 6 mm-tip catheter or radiofrequency (RF) ablation. Methods and results This is a retrospective case-control study including 80 patients with AVNRT treated with CRYO from March 2002 to June 2008. They were compared with another 80 consecutive patients who underwent RF ablation for AVNRT within the same period. Procedural success of 97.5 and 95% were achieved in CRYO and RF group, respectively. There was no permanent atrioventricular block (AVB) in the CRYO group, whereas two (2.5%) patients developed permanent first-degree or second-degree AVB in RF group (P ¼ 0.155). Higher recurrence was found in the CRYO group (9 vs. 1.3%; P ¼ 0.032) with no difference in the composite endpoint of procedural failure and recurrence between the groups (P ¼ 0.263). There was significantly shorter fluoroscopy time (18.6 + 10.8 vs. 25.9 + 17.0 min; P ¼ 0.002) and more energy applications required (3.1 + 1.7 vs. 1.9 + 1.1; P , 0.001) in the CRYO than the RF group. Conclusion Compared with RF ablation, CRYO with 6 mm-tip catheter for treating AVNRT results in higher recurrence and potentially lower incidence of permanent AVB. Fluoroscopy time has been shown to be reduced by CRYO.
Europace, 2007
Aims Within the last several years, transvenous cryo-ablation has become an alternative method to perform ablation of the slow-pathway. This study evaluated the acute and long-term safety and effectiveness of atrio-ventricular nodal re-entrant tachycardia (AVNRT) cryo-ablation. Methods and results The first 69 consecutive patients with AVNRT (60 slow-fast, 4 fast-slow, and 5 slow-slow) who underwent slow-pathway cryo-ablation were included. Mean age was 37 + 15, body weight 68 + 14 kg, symptom duration 125 + 104 months, and number of ineffective antiarrhythmic (AA) drugs 1.8 + 1.4. A 7 Fr cryo-catheter (Cryocath Âw ) was used, with initially 4-mm-tip and later with 6-mm-tip electrode. Cryo-mapping (n ¼ 7.9 + 8.4 per pt) was performed at the temperature of 2308C to test the effect on the target ablation site. Successful cryo-mapping was defined as abolition of nodal conduction jump or AV nodal refractory period prolongation. Cryo-ablation (n ¼ 5.1 + 4.9 per pt) was then applied by freezing to 2758C for 4 min in duration if no AV-block occurred. Acute procedural success (defined as AVNRT non-inducibility) after the first cryo-ablation attempt was achieved in 60/69 patients (87%). During cryo-ablation, inadvertent transient AV-block was encountered in 14 patients (five I AV-block and nine II-III AV-block). A mid-septal target site was the only variable correlated with inadvertent AV-block occurrence during cryo-ablation (P , 0.02). Long-term clinical success after cryo-ablation was globally achieved in 56/66 (85%) with a mean follow-up of 18+9 months (3 pts dropped-out). After the first procedure, 41/66 (62%) had no relapse, eight had a dramatic reduction in AVNRT duration-frequency and considered themselves cured, and five needed previously ineffective AA (with no relapse in three, drastic reduction in AVNRT duration-frequency in two). The five last patients needed one or more procedures, after which one had no recurrence and one had reduction in duration-frequency. Absence of recurrence after the first procedure was positively correlated with 6-mm-tip cryo-catheter use (,0.001) and negatively with acute procedural success (,0.001). At multivariate analysis, both were independently significant (,0.04 and ,0.008, respectively). Long-term clinical success was correlated only with 6-mm-tip cryo-catheter use (,0.001).
Journal of cardiovascular electrophysiology, 2017
Radiofrequency (RF) ablation is effective for slow pathway ablation, but carries a risk of inadvertent AV block requiring permanent pacing. By comparison, cryoablation with a 4 mm distal electrode catheter has not been reported to cause permanent AV block but has been shown to be less effective than RF ablation. We sought to define the safety and efficacy of a 6 mm distal electrode cryoablation catheter for slow pathway ablation in patients with atrioventricular nodal reentry tachycardia (AVNRT). Twenty-six US and eight Canadian centers participated in the study. Patients with supraventricular tachycardia (SVT) thought likely to be AVNRT were enrolled. If AVNRT was inducible and confirmed to be the clinical SVT, then the slow pathway was targeted with a cryoablation catheter using a standardized protocol of best practices. Acute success was defined as inducibility of no more than one echo beat after cryoablation. Primary efficacy was defined as acute success and the absence of docum...
Journal of Cardiovascular Electrophysiology, 2001
Cryoablation is a new method in interventional cardiac electrophysiology for percutaneous catheter ablation of cardiac arrhythmias. Cryothermal mapping enables the functional assessment of a particular site before permanent ablation. In this way, the targeted tissue may be confirmed as safe for ablation. This is useful in high-risk ablation, for example, next to the His bundle or the compact AV node. In the last decade, several studies have been addressed to AV-nodal reentry tachycardia (AVNRT) cryoablation. Current experiences indicate that cryoablation for AV-nodal reentry tachycardia is effective and safe. However, its wide use seems to be somewhat limited by a slightly lower efficacy when compared to radiofrequency. Further studies evaluating long-term success of cryothermal ablation versus radiofrequency are warranted. However, for high-risk ablations, cryoenergy is very helpful and should be systematically used. This article is a review of acute and long-term effects of cryoablation in patients suffering of AV-nodal reentry tachycardia episodes.
Circulation, 2000
Background —We report the first successful slow pathway ablation using a novel catheter-based cryothermal technology for the elimination of atrioventricular nodal reentrant tachycardia (AVNRT). Methods and Results —Eighteen patients with typical AVNRT underwent cryoablation. Reversible loss of slow pathway (SP) conduction during cryothermy (ice mapping) was demonstrated in 11 of 12 patients. Because of time constraints, only 2 sites were ice mapped in 1 patient. Seventeen of 18 patients had successful cryoablation of the SP. One patient had successful ice mapping of the SP, but inability to cool beyond −38°C prevented successful cryoablation. A single radiofrequency lesion at this site eliminated SP conduction. No patient has had recurrent AVNRT over 4.9±1.7 months of follow-up. During cryoablation, accelerated junctional tachycardia was not seen and was therefore not available to guide lesion delivery. Adherence of the catheter tip during cryothermy (cryoadherence) allowed atrial p...