70 likes | 463 Views
Different ablation techniques used in the treatment of AVNRT . Yang Chen ( Green Templeton College) & John Ward (New College). The Question.
E N D
Different ablation techniques used in the treatment of AVNRT Yang Chen ( Green Templeton College) & John Ward (New College)
The Question 37 year old female with a history of atrioventricular nodal re-entrant tachycardia. Would use of cryoablation offer any additional benefits in terms of post-procedure efficacy and safety over normal radiofrequency ablation?
The Search • PubMed Clinical Queries for: cryoablation AND radiofrequency ablation AND tachycardia °Web of Science for: cryoablation AND AVNRT OR atrioventricular nodal reentry tachycardia • >50 returned results. Collins et al 2006 selected as it compared the two therapies directly.
The Study appraisal Cryoablation versus radiofrequency ablation for treatment of pediatric atrioventricular nodal reentrant tachycardia: Initial experience with 4-mm cryocatheter • Recruitment – Retrospective case control study with similar patient populations in each treatment arm. Groups received identical treatment apart from inherent procedural differences (Table 1) • Ascertainment – Patient follow-up at 1 year was unavailable for 10% of patients in each group. • Measurements – Marker of success of procedure = lack of AVNRT inducibility (objective measurement), post-op and after 1 year. Complications of both procedures post-op and at 1 year. Collins et al 2006
The Results (interpretation of findings) • RF group: acute success rate = 100% (n=60) • Cryo group: acute success rate = 95% (n=57) P=0.11 • RF group: at 1 year, recurrence rate = 2% (n=53) • Cryo group: at 1 year, recurrence rate = 8% (n=49) P=0.19 • No permanent AV block observed in either group. Collins et al 2006
The Implications • For our patient, results suggest that both treatment arms offer very similar outcomes in terms of successful treatment of AVNRT and in lack of post-op complications • A larger sample size would be needed to tease out any potential differences in recurrence rates/ complications, in an e.g. RCT. • We would conclude for now that with our patient, she is no better off with cryoablation.