Atypical Electrocardiographic Features of Cavotricuspid Isthmus‐Dependent Atrial Flutter Occurring during Left Atrial Fibrillation Ablation

Abstract

A majority of patients with CTI-dependent AFL occurring during LA ablation have atypical ECG patterns. Biphasic flutter waves in the inferior leads are common ECG features, occurring in one-half of patients. Right atrial CTI-dependent AFL should be suspected even if the ECG appearance is atypical.

Catheter Ablation of Nonparoxysmal Atrial Fibrillation Using Electrophysiologically Guided Substrate Modification During Sinus Rhythm After Pulmonary Vein Isolation

“…CTI-dependent atrial flutter coexists in ≈5% to 9% of patients with AF. 39 As such, to prevent postablation typical atrial flutter and minimize the need for repeat procedures, CTI ablation with bidirectional conduction block as the end point was felt to be necessary during the index ablation, although this is contrary to current international guidelines. High-density mapping and substrate modification was limited to the LA.…”

Atrial Tachycardias After Atrial Fibrillation Ablation Manifest Different Waveform Characteristics: Implications for Characterizing Tachycardias

“…described that approximately 20% of ATs in persistent AF ablation patients were due to a small reentrant circuit, manifesting ECGs with short p‐wave duration and long diastolic intervals, and concluded that such insights derived from ECG analysis “would be helpful during mapping of postablation ATs.” Chyou et al . reported on the atypical electrocardiographic features of CTI‐dependent atrial flutter in AF ablation patients, concluding that 85% of CTI‐dependent right ATs had atypical features on ECG analysis . These findings point out the atypical nature of many ATs that occur in postablation patients, the diagnostic difficulties inherent in visual inspection of ECGS in such patients, and the need for more refined methods to noninvasively diagnose these ATs.…”

“…Simple visual ECG inspection is often sufficient to differentiate between rhythms such as AF versus AT, even after a previous catheter ablation procedure. However, the specificity of ECG findings for accurate diagnoses of postablation AT subtypes is compromised after catheter ablation of atrial substrate in AF patients . Therefore, visual diagnosis of ATs, including even the common type of right atrial flutter, can be fraught with difficulty.…”

“…However, the specificity of ECG findings for accurate diagnoses of postablation AT subtypes is compromised after catheter ablation of atrial substrate in AF patients. 3,4 Therefore, visual diagnosis of ATs, including even the common type of right atrial flutter, can be fraught with difficulty.…”

“…1,2 Diagnoses of post-AF ablation ATs are difficult to perform for 2 main reasons: (1) visual inspection of electrocardiograms (ECGs) is limited by high incidence of atypical ECG morphologies, even for right atrial cavotricuspid isthmus (CTI)-dependent "typical" ATs, (2) activation mapping during electrophysiology (EP) studies can be limited by low amplitude, fractionated electrograms that preclude accurate analysis, and (3) entrainment mapping during EP studies can result in AT termination or transformation, therefore compromising the diagnostic ability of these maneuvers. [3][4][5][6][7] There is therefore a need for improvement in diagnostic strategies that can help to characterize the differences among common AT subtypes in postablation AF patients more effectively. Past studies have utilized noninvasive, temporospatial methods of signal analyses to differentiate various types of right ATs from other supraventricular tachycardias such as atrioventricular nodal reentrant tachycardia in patients with no prior ablation treatment.…”