Pacemakers dependency assessment

Fig. 19.2 Assessment of pacemaker dependency, (a) Totally paced ventricular rhythm when the base rate is reduced to 30 ppm in a nontracking (DDI) mode in a patient who has asystoUc complete heart The P waves that occur during the atrial alert period are identified by event markers as are all the ventricular paced complexes, (b) Underlying 2 1 block rhythm is identified in a patient with a DDD pacemaker whose ventricle is normally totally controlled by the permanent pacemaker. To show this, the mode was temporarily changed to VVI and the pacing rate reduced to 30 ppm. The simultaneously telemetered unipolar atrial electrogram is shown along the bottom demonstrating the atrial activity as well as far-field ventricular signals.

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