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The Apparent and the Effective PR Interval, Insights for Cardiac Pacing
1Assistant Professor, Cardiologist, USEK- NDS University Hospital, Byblos, Lebanon.
Abstract:
A 75-year-old-male patient with dual chamber pacemaker presented with a bizarre EKG showing a unique spike within the QRS complex. Apparent PR interval was 160 ms and effective atrio-right ventricular delay was 210 ms due to right bundle branch block. Sensed AV delay was set at 180 ms causing pseudofusions. Insights regarding cardiac pacing are presented.
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