A 60-year-old woman with hypertension, diabetes mellitus, and intermittent atrial fibrillation presents with nausea, diaphoresis, dizziness, and global weakness that has lasted 1 hour. She denies chest pain, dyspnea, syncope, vomiting, diarrhea, blood loss, and headache; there is no vertigo. Medications include acetaminophen, digoxin, diltiazem, glipizide, hydrochlorothiazide, irbesartan, metformin, pioglitazone, and warfarin.
Vital signs are normal. The patient is mildly nauseated but otherwise in no acute distress. The skin is dry, the lungs are clear, and the heartbeat is regular, without abnormal sounds. Palpation of the abdomen reveals diffuse mild tenderness without guarding or signs of peritoneal problems. There is symmetric trace pitting edema in the pretibial area. Results of a neurologic examination are normal except for an unsteady gait; however, there is no true ataxia.
Venous access is secured, and a 12-lead ECG is obtained. Meanwhile, a fingerstick glucose test shows a level of 43 mg/dL, which suggests that the patient’s symptoms are the result of a hypoglycemic episode. Her symptoms resolve after supplemental glucose is administered, but the findings on a second ECG remain unchanged.
Which of the following best explains the ECG findings?A. Acute coronary syndrome.
B. Left ventricular hypertrophy with repolarization abnormality.
C. Left bundle-branch block.
D. Digitalis effect.
E. Hypokalemia secondary to the thiazide diuretic.
F. Hypercalcemia secondary to the thiazide diuretic.
