DP+1: another simple endpoint for atrial flutter ablation.

Area of Science:

• Electrophysiology
• Cardiac Ablation
• Arrhythmia Management

Background:

• Verifying complete bidirectional block (CBDB) after atrial flutter ablation is crucial for procedural success.
• Traditional methods using double potentials (DP) on the line of block are not always visible.
• A need exists for a reliable alternative method to confirm block during ablation procedures.

Purpose of the Study:

• To introduce and validate a novel electrogram interval measurement, termed "DP+1", for verifying CBDB.
• To assess the efficacy of the DP+1 interval compared to DP in atrial flutter ablation.

Main Methods:

• Fifty patients undergoing atrial flutter ablation with a duodecapolar catheter were studied.
• The DP+1 interval was measured between electrogram pairs adjacent to the ablation line.
• Radiofrequency ablation was performed until a specific activation pattern was achieved.

Main Results:

• The DP+1 interval was measurable in all patients, unlike DP which was only visible in 44%.
• A DP+1 interval of 160 +/- 18 ms indicated CBDB, significantly different from 81 +/- 10 ms when block was absent (P < 0.001).
• A DP+1 interval >140 ms demonstrated 100% specificity and 96% sensitivity for confirming CBDB.

Conclusions:

• The DP+1 interval is a simple and effective method for verifying CBDB when DP are not visible.
• A DP+1 interval exceeding 140 ms reliably confirms successful bidirectional block in typical atrial flutter ablation.
• This method enhances the ability to confirm procedural success in atrial flutter ablation.