Management of Atrial Flutter (AFL) Using Intrinsic Antitachycardia Pacing (iATP) Protocol.

Area of Science:

• Cardiology
• Electrophysiology
• Medical Devices

Background:

• Traditional atrial flutter (AFl) management involves catheter ablation and pharmacotherapy.
• Antitachycardia pacing (ATP) offers variable efficacy for atrial arrhythmias.
• The intrinsic ATP (iATP) algorithm, proven for ventricular tachycardia, may enhance atrial arrhythmia termination via programmed stimulation (PS).

Purpose of the Study:

• To evaluate the efficacy of iATP in terminating AFl.
• To compare iATP performance against traditional ramp pacing protocols.

Main Methods:

• A prospective, randomized crossover trial involving patients undergoing AFl ablation.
• Testing three ATP protocols: ramp pacing (91% and 81% tachycardia cycle length [TCL]) and iATP with PS.
• Primary endpoint: AFl termination or acceleration to atrial fibrillation (AF).

Main Results:

• iATP achieved a 38% AFl termination rate, significantly higher than ramp pacing (17.6% and 20.5%).
• iATP also induced AF in 8 patients, compared to 1 and 4 in ramp pacing groups.
• Enhanced efficacy of iATP is linked to introducing premature wavefronts into the excitable gap.

Conclusions:

• iATP demonstrates superior efficacy in terminating AFl and converting it to AF versus traditional ramp pacing.
• These findings support iATP as a potential pacing-based intervention for atrial arrhythmia management.
• Further research should explore iATP's applicability in atypical AFl and AF.