The underlying cause you should suspect during the 12-lead ECG test on the patient is Hypokalemia.
Hypokalemia is a medical disorder that results from low levels of potassium in the blood.
During 12-lead ECG test, hypokalemia can cause dynamic changes in T-wave morphology and prolonged QT intervals.
Thus, the underlying cause you should suspect during the 12-lead ECG test on the patient is Hypokalemia.
Learn more about Hypokalemia here: https://brainly.com/question/2207810
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