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Answer to a Quiz: ECG-Pacemaker on page 26 and case discussion

Answer: Correct answer 4 In this patient with moderate left ventricular ejection fraction depression at 45%, and permanent atrial arrhythmia with fast ventricular response, despite several radiofrequency ablation procedures, a strategy of atrioventricular node ablation and His bundle pacing (as an alternative to biventricular pacing) has been proposed. His bundle pacing has just been integrated in the last American guidelines on pacing in 2018 (1). In this specific setting, no atrial lead is then needed. At the beginning of the experience, some centers are adding a back-up ventricular lead, in case of Hissian lead dysfunction or dislodgement (pacemaker-dependent patient). This was the case in this patient. The landmark of selective His bundle capture is the identical QRS morphology between native QRS and paced-QRS complexes (Fig. 1).