Objective      To investigate the efficacy of different ablation strategies

maximum voltage-guided (MVG) ablation

polarity reversal-guided ablation and linear ablation

on patients with cavotricuspid isthmus (CTI)-dependent atrial flutter.       Methods      Thirty-four patients with typical

atrial flutter were randomly divided into group A

group B and group C. In group A (n=12) continuous linear ablation was performed at CTI. In group B (n=11)

MVG ablation was performed at CTI. In group C (n=11) radiofrequency (RF) ablation guided by reversal of polarity was performed at CTI. In each group

when bidirectional isthmus block was not achieved after the ablation strategies

residual conduction gaps were mapped and eliminated by additional RF application. The following parameters were compared: acute success rate

recurrence rate in long-term follow-up

operation time

X-ray exposure time

number of RF applications

and total RF ablation duration.       Results      Bidirectional isthmus block was achieved in all patients except for 1 case in group C

without serious complication. There were lower mean number of RF applications (group A

23.2±8.7; group B

13.4±3.6; group C

7.2±3.1;

P

0.01) and shorter total RF duration (group A

15.4±6.8 min; group B

6.7±3.5 min; group C

5.4±2.6 min;

P

0.01) in group B and group C than in group A. Operation time (group A

70.0±45.1 min; group B

50.8±30.5 min; group C

65±38.5 min;

P

0.05) and X-ray exposure time (group A

15.2±7.2 min; group B

10.3±6.5 min; group C

16.3±8 min;

P

0.05) were shorter in group B than in other two groups. No difference was observed in respect of recurrence rate in long-term follow-up (2 in group A vs 1 in group B vs 1 in group C).       Conclusion      MVG and polarity reversal-guided ablation strategies are associated with fewer RF applications and shorter ablation duration as compared to linear ablation strategy. Furthermore

MVG ablation strategy has shorter operation and X-ray exposure time than reversal-guided ablation strategy.