ST-Segment Elevations Secondary to Electrical Cardioversion
A 56-year-old woman with primary pulmonary hypertension presented with increasing shortness of breath and palpitations. ECG showed right bundle-branch block and slow atrial flutter with 2:1 AV block (Figure 1). In view of the patient’s hypotension and worsening renal function, she was cardioverted into normal sinus rhythm with a 360-J direct current shock. Immediately after the cardioversion, the ECG showed marked ST-segment elevations in the anterolateral leads (Figure 2). At this time, the patient was asymptomatic, and hence, a repeat ECG was performed, which showed complete resolution of the ST-segment elevations (Figure 3). Cardiac enzymes and electrolytes were normal. Transient elevation of the ST segment after electrical cardioversion has been very well reported in the literature, with an incidence as high as 16%. The mechanism of these ST-segment elevations is not clear.