Hypercalcemia due to primary hyperparathyroidism sometimes triggers the development of fatal arrhythmias. Herein, we report a patient with parathyroid cancer, who developed cardiac arrest due to a fatal arrhythmia caused by hypercalcemia, in whom parathyroid surgery was performed after resuscitation and recovery.
A 62-year-old man lost consciousness when he stood up to make tea after dinner. His daughter performed a cardiac massage for him. After the ambulance crew arrived, they conducted defibrillation, administered adrenaline, and performed the maneuvers for cardiopulmonary resuscitation.
Laboratory investigation of the patient revealed hypercalcemia (14.8 mg/dL) and a high serum level of intact parathyroid hormone (PTH; 279 pg/mL), indicative of primary hyperparathyroidism. Cervical ultrasonography revealed a solid mass measuring 20×17×15 mm with unclear boundaries in the thyroid gland. 99mTc-MIBI scintigraphy showed accumulation of 99mTc-MIBI at the same site in the late phase. Paralysis of the right vocal cord was observed. Therefore, surgery was performed under the suspicion of parathyroid cancer.
During the operation, invasion of the recurrent laryngeal nerve was observed. Right thyroidectomy and parathyroidectomy were performed. Intraoperative examination confirmed that the patient’s serum intact PTH levels had decreased, and the operation was completed. Histopathology of the resected specimen revealed the diagnosis of parathyroid cancer. The postoperative course was good, and no local recurrence or distant metastasis was observed after 2 year.
We wish to reaffirm the risk of fetal arrhythmias caused by hypercalcemia and the need to recognize that the diagnosis of parathyroid carcinoma should be based on a combination of physical, laboratory, and imaging findings.
