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Relationship between polarity of the flutter wave in the surface ECG and endocardial atrial activation sequence in
Naohiro Oshikawa1, Ichiro Watanabe, Riko Masaki
1The Second Department of Medicine, Nihon University School of Medicine, Itabashi-Ku, Tokyo, Japan. ossi@med.nihon-u.ac.jp
Insights
Simultaneous atrial mapping in typical atrial flutter (AFL) reveals how electrical activation patterns influence ECGs. Left atrial conduction pathways are key determinants of ECG morphology in AFL patients.
Area of Science:
- Electrophysiology
- Cardiac Arrhythmias
- Electrocardiography
Background:
- The relationship between electrocardiogram (ECG) and atrial activation in typical atrial flutter (AFL) remains unclear.
- Previous studies lacked simultaneous multisite right and left atrial mapping.
Purpose of the Study:
- To define the relationship between ECG and atrial activation patterns in typical AFL.
- To investigate the role of interatrial conduction in AFL ECG morphology.
Main Methods:
- Simultaneous right and left atrial activation mapping was performed in 13 patients with AFL.
- Catheters recorded electrical activity from the tricuspid annulus, right atrial appendage, His bundle, coronary sinus, Bachmann's bundle region, and esophagus.
Main Results:
- In counterclockwise AFL, negative flutter waves correlated with specific activation sequences (CS, esophagus, Bachmann's bundle).
- Positive flutter waves in counterclockwise AFL showed earlier Bachmann's bundle activation.
- In clockwise AFL, positive flutter waves showed Bachmann's bundle activation preceding the esophagus and coronary sinus.
Conclusions:
- Interatrial conduction pathways (upper and lower) significantly determine ECG morphology in AFL.
- Understanding these activation patterns aids in diagnosing and managing atrial flutter.
Background:
The relation between ECG and activation patterns within atria in typical atrial flutter (AFL) patients (pts) has not been defined due to the lack of simultaneous multisite right and left atrial mapping.
Methods:
In 13 pts with AFL, a Halo catheter was positioned along tricuspid annulus and multipolar catheters were placed in right atrial appendage, His bundle region, coronary sinus (CS), proximal portion of right pulmonary artery (Bachmann's bundle region, BB) and esophagus (Eso) to record right and left atrial activation simultaneously.
Results:
In counterclockwise (CCW) AFL (11 pts), 9 showed negative flutter wave (F) and 2 positive F in the inferior leads. CCW/negative F; CS electrograms (EGs) were proximal to distal, Eso EGs were inferior to superior and BB activation was later than CS and Eso. positive F; BB activation was earlier than CS. Eso EGs were superior to inferior or simultaneous. In clockwise (CW) AFL (7 pts), 5 showed positive F and 2 negative F. CW/positive F; BB activation preceded Eso and CS. Eso EGs were superior to inferior. CS EGs were proximal to distal (1), middle to proximal, distal (3) or proximal, distal to middle (1). negative F; CS EGs were proximal to distal. CS activation was earlier than BB or CS and BB activation were simultaneous. Eso EGs were inferior to superior.
Conclusion:
Impulse conduction to the left atrial free wall through either lower or upper interatrial connection is a major determinant of ECG morphology in AFL.
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