Electroanatomical mapping– and CT scan image integration–guided pacing lead implantation: A case series and review of the recent literature

Figures

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  Figure 1. A: Atrial lead placed at upper right atrial septum (as indicated by yellow arrows). The red arrow shows the location of the His signal. To the right: the electrocardiogram (ECG) with intrinsic rhythm and atrial septal paced rhythm, as indicated by relatively narrow p waves and comparably short AV interval. The map projections are to the left close to left anterior oblique and to the right a more septal view. ICV = inferior caval vein; SVC = superior vena cava. B: The septal aspect of the right ventricle (RV) is shown with a map of activation of the septum during sinus rhythm. The red arrow shows the His location. The yellow arrow shows the position of the right ventricular lead close to the earliest activated septal site with the paced ECG shown to the right with a rather short duration of the QRS complex. CS = coronary sinus; OT = right ventricular outflow tract. C: Right ventricular map from septal aspect. The blue arrow shows the final lead right ventricular lead position in an approximate midseptal position. The His location is shown at the yellow point tags. In this patient, who had left bundle branch block (LBBB) even though His capture was obtained, the LBBB duration was…

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  Figure 2. A: Map of right atrium with His location in left anterior oblique and a more septal view with yellow arrows pointing to the final lead position at the yellow tags for His location. Below is shown to the left the His-paced electrocardiogram (ECG) with selective His capture and the intrinsic rhythm to the right below. B: A restricted map is shown from a patient where the His was very easily located and only His location with immediate surrounding anatomy to navigate the His lead to the final position, shown by yellow arrows to the His tags in green and yellow, and the largest His amplitude, measured at the red point tag. Below: ECG with nonselective His capture and the intrinsic rhythm to the left and right, respectively. Note the larger “His cloud”; see discussion. C: Examples of tracings obtained from EnSite (Abbott, Abbott Park, IL) (1) and “Prucka” (GE Healthcare, CA, USA) electrophysiology system with His to QRS and His paced to QRS almost the same duration, from a patient with right bundle branch block and narrow QRS (2,3 and 4,5 respectively).

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  Figure 3. A,B: Electroanatomical mapping aligned with segmented coronary sinus from computed tomography (CT) scan, with coronary sinus decapolar mapping catheter in target vein identified from the CT. C: Coronary sinus catheter with wire in target vein. D: Vein selector advanced over the wire after removal of coronary sinus catheter and venography showing vein branch from target vein in near-optimal position. E: Left ventricular lead in target vein with the tip in the branch in final position.

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  Figure 4. Final lead position on radiography after the procedure (A: frontal plane; B: lateral); C: “right ventricular” lead is seen on echocardiography. A:Red arrow directed at the septal lead tip. Yellow arrow is pointing towards coil in azygos vein (AZV). B:Yellow arrow pointing toward left ventricular lead in posterior location. Red arrow is pointing towards AZV coil. Black arrow is pointing towards septal lead. C: Parasternal long-axis view tilted to show the septal lead from atrial aspect with tip in the septum (red arrow). D: Fusion of electroanatomical map (EAM) and segmented computed tomography (CT) (green for coronary sinus [CS] and target veins) for defining CS target veins. Yellow tags indicate His location. ICV = inferior caval vein; SVC = superior vena cava. E: Fusion of CT and EAM for locating AZV take-off. Red arrow points at the bulb indicating the entrance of AZV on CT, while blue is the EAM of the AZV. The yellow arrows point to the tags for 2 potential locations of the bipole of the implantable cardioverter-defibrillator lead in location in AZV. The lead was left with the tip at the proximal tag.

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  Figure 5. Map demonstrating map shift. Yellow dots represent His location initially mapped. Blue dots are His locations after remapping, demonstrating map shift. Right atrium is shown in different angles, as seen from torso icon in right upper corners. Abbreviations as in Figures 1 and 2. RA = right atrium. In A the yellow arrow is pointing between atrial lead position marker before and after remapping. Red arrow in B points similarly for right ventricular lead. In A the red lead icon demonstrates final His lead position. Red arrow is pointing between CS lead icons before and after map shifts. The blue dots represent also another minor map shift. Only the lower tags were verified to be His location at the final mapping.