Endocrine Abstracts

Introduction: Hypocalcaemia is a rare and potentially reversible cause of cardiomyopathy. Restoration to normal serum calcium levels usually leads to rapid improvement of cardiac function.

Case report: A 42-year-old woman with a history of total thyroidectomy, due to large nodular goiter in 2016, and acute pos-operative hypoparathyroidism, assumed to be transient, with no supplementation since early 2017. In September 2018 she was admitted due to acute cardiac failure, bronchospasm and retrosternal discomfort. At presentation, she also referred circumoral paraesthesia’s, generalized muscular weakness and muscle spasms since the previous week. Chest radiograph showed mild cardiomegaly with signs of pulmonary congestion; prolonged QT-interval and some ST segment depression in V4-V6 on ECG; akinesia in left ventricular septum and apex with moderate-to-severe global left ventricular dysfunction on transthoracic echocardiography. Laboratory tests revealed severe hypocalcaemia (serum ionized calcium of 0.77 mmol/l; reference 1.13–1.32) with hyperphosphatemia (1.89 mmol/l; reference 0.87–1.45) and an inappropriately ‘normal’ PTH (18.9 pg/ml; reference 15–65). Treatment was immediately initiated with intravenous calcium and active vitamin D supplementation with a quick and positive clinical response. Left ventricular function was fully recovered after restoration of normal plasma calcium levels. At last clinical reassessment, she was asymptomatic with corrected total serum calcium level of 2.39 mmol/l (reference 2.10–2.65) and phosphorus level of 1.31 mmol/ (reference 0.87–1.45), under supplementation with 3 g of elemental calcium and 1 mcg of calcitriol.

Conclusion: This case report highlights the importance of considering hypocalcaemia as a potentially reversible cause of severe cardiac dysfunction. Surgical hypoparathyroidism usually occurs within few days after surgery but it can remain subclinical during several years, being only recognized later during acute exacerbation events.