The nurse is reviewing the electrocardiogram (ECG) of a client admitted for acute pericarditis. Which ECG change does the nurse anticipate?

A. Peaked T waves: Peaked T waves are most commonly associated with hyperkalemia and are not a characteristic finding in acute pericarditis. Relying on this sign could lead to misinterpretation of the underlying cardiac condition. B. ST Elevation: Acute pericarditis typically causes diffuse, concave upward ST-segment elevations across multiple ECG leads without reciprocal ST depression. This reflects inflammation of the pericardial layers affecting the myocardial electrical activity. ST elevation in this context is a hallmark indicator of pericardial inflammation rather than myocardial infarction. C. Wide QRS complexes: Widened QRS complexes suggest bundle branch block or ventricular conduction delay, which are not typical findings in pericarditis. QRS morphology usually remains normal in pericardial inflammation unless concurrent conduction system disease exists. D. Sinus Arrhythmia: Sinus arrhythmia represents a normal variation in heart rate during the respiratory cycle. It is not specifically associated with pericardial inflammation and would not serve as a diagnostic ECG finding in acute pericarditis.