Journal: HeartRhythm Case Reports

Article Title: Changes in QRS morphology during catheter ablation of premature ventricular complexes origination from right ventricular false tendon: A case report

doi: 10.1016/j.hrcr.2025.12.005

Figure Lengend Snippet: Intracardiac echocardiography view, 3D structure model, and QRS morphology changes of PVCs. A : ICE imaging shows the FT connected the APM and PPM. B : Right ventricular electroanatomical model in right anterior oblique and left anterior oblique projections showed the positions of the moderator band ( brown ), APM ( cyan ), FT ( purple ) and PPM ( rifle green ). The EAS was initially localized to the PPM apex ( pink tag ). Following ablation at this site, the EAS shifted to the FT-PPM junction ( blue tag ), with ultimate elimination of the PVCs achieved at the FT-APM junction ( yellow tag ). C1-C3 : QRS morphological alterations were documented during ablation at the corresponding EASs. A Purkinje-like potential was recorded during PVCs without identified during sinus rhythm ( red arrow ). APM = anterior papillary muscle; EAS = earliest activation site; FT = false tendon; MB = moderator band; PPM = posterior papillary muscle; PVCs = premature ventricular complexes.

Article Snippet: Considering the unusual QRS morphology of PVCs, using intracardiac echocardiography (ICE) with 3-dimensional electroanatomical mapping system (CARTO3; Biosense Webster, Inc) was required for identification of RV endocavitary structures.

Techniques: Imaging, Activation Assay

Journal: Journal of Cardiology Cases

Article Title: Reentrant atrial tachycardia after catheter ablation of coronary sinus accessory pathway

doi: 10.1016/j.jccase.2025.05.004

Figure Lengend Snippet: (A) 12‑lead electrocardiogram (ECG) during sinus rhythm. (B) Simultaneous ECG and intracardiac electrogram (EGM) recordings during ventricular extrastimuli demonstrate that the earliest atrial activation site is consistently at the distal electrode in the coronary sinus, regardless of coupling interval [400 ms (left) or 320 ms (right)]. These findings indicate the absence of decremental properties in the ventriculoatrial pathway. (C) 12‑lead ECG during narrow QRS complex tachycardia (SVT1) with a heart rate of 175 bpm. (D) ECG and EGM during SVT1 reveal that the atrial activation sequence during the tachycardia cycle (345 ms) is identical to that observed during ventricular pacing. Numbers indicate intervals in milliseconds.

Article Snippet: Fig. 2 (A) Activation maps during ventricular pacing using the 3-dimensional anatomical mapping system (CARTO 3; Biosense Webster).

Techniques: Activation Assay, Sequencing

Journal: Journal of Cardiology Cases

Article Title: Reentrant atrial tachycardia after catheter ablation of coronary sinus accessory pathway

doi: 10.1016/j.jccase.2025.05.004

Figure Lengend Snippet: (A) Activation maps during ventricular pacing using the 3-dimensional anatomical mapping system (CARTO 3; Biosense Webster). The upper panel shows the initial activation map of the left atrium in the anterior-posterior (AP) view, with its earliest atrial activation site (EAAS) located at the anterior mitral annulus (MA). The lower panel demonstrates the activation map after the EAAS shifted to the lateral MA. Pink and red tags indicate the radiofrequency ablation sites along the anterior and lateral MA applied at 30 W for up to 60 s using the ThermoCool SmartTouch SF ablation catheter. (B) Tracings during ventricular extrastimuli without ( left ) and with ( right ) ventriculoatrial (VA) block. Coronary sinus (CS) recordings are displayed at twice the usual scale. Red arrowheads indicate low voltage and fractionated potentials immediately after ventricular far-field potentials at the CS electrodes, which are observed only in the presence of VA conduction. (C) Intracardiac electrogram at the distal electrode of the ablation catheter during ventricular pacing exhibits the accessory pathway potential fused with far-field ventricular potential. (D) Catheter positions at the successful ablation site in the left anterior oblique (LAO) projection. A few radiofrequency ablations were applied at 15 or 20 W, each for 30 s. ABL, intracardiac electrogram recorded from the ablation catheter.

Article Snippet: Fig. 2 (A) Activation maps during ventricular pacing using the 3-dimensional anatomical mapping system (CARTO 3; Biosense Webster).

Techniques: Activation Assay, Blocking Assay