Answer - Case of the month (Oct 2011)
Q: This patient had a severe electrolyte disorder (and no ischemia). Which electrolyte disorder?
Answer: B. Potassium levels was severely elevated: 7.5 mmol/L. Note the flattened P wave. The widened QRS and the abnormal repolarization.
Also compare ECGs 3 and 4 which were made during correction of potassium levels. ECG 3 clearly shows peaked T waves.