Electrocardiographical case. J wave and presyncope in a middle-aged woman

A 46-year-old woman presented with three episodes of presyncope in the previous two days. Electrocardiogram (ECG) showed sinus rhythm, relatively short QT interval (QTc of 340 msec) and prominent J-waves in the inferior leads. Biochemical evaluation revealed serum calcium of 17.4 mg/dL, phosphorus of 2.3 mg/dL and alkaline phosphatase of 533 IU/ml. She was managed with saline diuresis followed by elective parathyroidectomy. ECG became normal with the disappearance of J-waves after correction of hypercalcaemia. She was asymptomatic at six months of follow-up. The presence of J-waves (Osborne waves) in hypercalcaemia has rarely been reported.