Electrocardiographic J wave as a result of hypercalcemia aggravated by thiazide diuretics in a case of primary hyperparathyroidism.

Electrocardiographically, the QT interval is shortened, ST segment is depressed, and T wave becomes negative in hypercalcemia. The use of diuretics in cases with hyperparathyroidism decreases the excretion of calcium, causes changes in bone-calcium turnover and parathyroid hormone activity, and forms hypercalcemia. A 67 year-old Turkish female patient in whom we electrocardiographically observed a J wave is presented as a hypercalcemic case with primary, hyperparathyroidism aggravated by the use of a thiazide diuretic.