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Patient received a dual chamber pacemaker for SSS and dizziness.
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Day 1 check demonstrated the ECG below.
There are 2 pacing spikes at a very short interval from each other (80ms)
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The 1st spike appears to be capturing ventricle (broad complex)
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Underlying rhythm is sinus, but there does not seem to be a relationship between p wave and paced complex.
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Does not appear to be a biventricular device, base on the
paced QRS morphology
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This is consistent with atrial lead dislodgment resulting in V safety pacing
Ventricular safety pacing
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After each atrial pacing event there is a ventricular blanking period (not after an atrial sensed event). This is to prevent crosstalk.
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Crosstalk is defined as the ventricular lead oversensing the atrial pacing arefact, which would result in pacing inhibition.
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In a dependent patient, this would result in ventricular standstill.
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As a safety mechanism, if a V sensed event occurs in the cross talk window, a backup V stimulus is delivered (80ms) just in case of inhibition.
