A challenging ECG: a case of a lengthening PR interval
David Sanders1, Leo Ungar2, Arnold H Seto3
1Department of Cardiology, Rush University Medical Center, Chicago, IL, USA.
Abstract:
A 62-year-old man presented to the emergency department with shortness of breath and chest tightness. His initial ECG appeared to have an ectopic P-wave with a lengthening PR interval consistent with second degree AV block - Mobitz Type I. But closer inspection showed a faster, independent atrial rate. The patient was diagnosed with ectopic atrial bradycardia with complete AV block and junctional escape, and was ultimately referred for pacemaker.
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