Abstract：Objective To evaluate the effect of increased contact force ablation in patients with atrioventricular nodal reentrant tachycardia (AVNRT) after unsuccessful routine procedure. Methods Five retrospective cases (no evidence of organic heart disease) admitted in Characteristic Medical Center of Chinese People's Armed Police Force between October 2017 and April 2021 were enrolled. Through Carto-3 system, the patients underwent ablation according to conventional method. After continuous junction rhythm appeared which meant the effective ablation endpoint, AVNRT could still be induced. Increased contact force was applied upon the first-time marked ablated point sequentially and the tachycardia was triggered repeatedly. Continuous radiofrequency ablation was performed at the non-induced point. Results Successful ablation was achieved in all 5 cases and the mean procedure time was (9.4±2.4) min. Tachycardia could not be induced at mean contact force of (15.4±2.2) g. Maximal contact force of ablation was (10.4±2.3) g, which was significantly higher than that of routine method [(5.8±1.6) g, P＜0.01]. The cumulative radiofrequency time was (68.6±8.5) s and no serious complications occurred. No recurrence of tachycardia occurred at mean (18.6±14.4) months follow-up. Conclusions Increased contact force ablation is simple, safe and effective in treating refractory AVNRT when conventional ablation fails.
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2022, Vol. 33 
