Ablation of parahisian premature ventricular extrasystoles by subtricuspid retrograde approach using inverted catheter technique: back to the anatomy

Figures

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  Figure 1. (A) ECG of PVC; (B) local electrogram preceding the QRS by 12 msec at the earliest site during antegrade mapping. Note that the proximal bipole has his and atrial signal in sinus beats. (C and D) left anterior oblique and anteroposterior views of the ablation catheter, respectively.

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  Figure 2. (A) Local electrogram preceding the QRS by 24 msec with a QS signal at the unipolar recording at the retrograde earliest site denoted by the blue dot; (B) right ventricular view of the ventricular septum and ablation lesions; (C) solid right ventricular and transparent left ventricular septum viewed from left anterior oblique projection; (D) left inferior view of confluence of right and left septal walls forming the muscular crest; (E, F, and G) left anterior oblique, anteroposterior, and right anterior oblique projection of the inverted ablation catheter, respectively. For all electroanatomic maps, blue dot denotes the earliest and successful ablation site, red and white spots are ablations during antegrade attempt, and yellow spots are where local electrogram has prominent his potentials in sinus beats.

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  Figure 3. Schematic drawing of parahisian and muscular crest region depicting the anatomical relations and direction of the ablation catheter according to approach route. “X” denotes the hypothetical arrhythmia focus at the muscular crest. His bundle and branches are drawn yellow. AVN, atrioventricular node; IVS, interventricular septum; LV, left ventricle; RV, right ventricle.