An 81-year-old male presents with a history of diabetes mellitus, chronic obstructive pulmonary disease (COPD), lung cancer, S/P radiation therapy, end stage kidney disease, and coronary artery disease with a recommendation to have coronary artery bypass graft (CABG). The patient complains of weakness and shortness of breath. He decides to spend time in a skilled nursing home facility before undergoing CABG.
An ECG is performed (Figure 1).
The correct answer is: G. A, B, C and E
The ECG shows a regular atrial rhythm with an ectopic atrial focus originating from left lower atrium (negative in lead I, II, III, aVF, and V3-v6). The QRS duration is prolonged with right bundle branch block pattern. Inferior Q waves and increased R wave anteriorly (V1-V2) are diagnostic of inferior-postero-lateral infarction. The T wave is narrow secondary to hyperkalemia (potassium serum level was 5.8 mg/dl).
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- Dittrich KL, Walls RM. Hyperkalemia: ECG manifestation and clinical considerations. J Emerg Med 1986;4:449-55.