[Contribution of atrial activation to the segment of the typical atrial flutter wave: an electro-anatomic insight into the electrocardiogram morphology]

Area of Science:

• Cardiology
• Electrophysiology
• Medical Imaging

Background:

• Atrial flutter is a common supraventricular tachycardia.
• Cavatricuspid isthmus-dependent counter-clockwise atrial flutter (CTI-AFL) is a specific type of atrial flutter.
• Understanding the relationship between intra-cardiac activation and surface electrocardiogram (ECG) findings is crucial for diagnosis and treatment.

Purpose of the Study:

• To investigate the translation of intra-cardiac activation into the characteristic flutter wave in CTI-AFL.
• To correlate 3D electroanatomic mapping data with surface ECG findings in CTI-AFL patients.

Main Methods:

• Utilized a 3-dimensional mapping system to reconstruct activation maps of the left and right atria during CTI-AFL.
• Analyzed surface ECG flutter waves in conjunction with intra-cardiac activation patterns.
• Included 15 hospitalized patients with CTI-AFL.

Main Results:

• The flutter wave in inferior leads demonstrated three distinct parts: slow downward, sharp downward, and terminal positive.
• These ECG components corresponded to specific segments of the macro-reentry circuit.
• Activation mapping was successfully completed in all participants.

Conclusions:

• The characteristic flutter wave in CTI-AFL is primarily determined by the unique macro-reentry activation within the right atrium.
• Left atrial activation plays a role in shaping the downward deflection of the flutter wave.