• calcium level
• calcium supplementation
• dilated cardiomyopathy
• hypoparathyroidism

Hypocalcemia and its related symptoms are common manifestations in postsurgical hypoparathyroidism, but patients with hypocalcemia manifested as heart failure is rare and few cases are reported in the literature. Here we reported a 58-year-old female with hypoparathyroidism and uncontrolled hypocalcemia after thyroidectomy, presented with acute heart failure, accompanied with enlargement and reduced ejection fraction of left ventricle. She was refractory to guideline-directed medical therapy for heart failure including digitalis and diuretics. However, her symptoms resolved and cardiac function improved dramatically after normalization of serum calcium level. This rare case highlights the pivotal role of calcium in maintaining cardiac function and the importance of treating underlying reversible causes of heart failure. For patients with hypoparathyroidism, it is essential to get standard treatment to avoid development of heart failure and hypocalcemia related syndromes.

Hypoparathyroidism is a rare disease that may occur due to primary or secondary etiologies. The estimated incidence in the United States is 24–37/100000 person-years. Congestive heart failure associated with hypocalcemia due to hypoparathyroidism is an even rarer presentation.

Here, we present a 64-year-old woman with congestive heart failure following hypocalcemia. The patient was transferred to our emergency department with complaints of rapidly progressive dyspnea, shortness of breath and heaviness of the chest for 4 d. She had a history of undergoing thyroidectomy and partial tracheotomy 2 years prior due to a malignant thyroid tumor. Muscle spasms had been present 1 year ago, and cataracts were treated with intraocular lens replacement in both eyes. Most tests were within normal ranges, except serum calcium at 1.33 mmol/L (2.20–2.65 mmol/L), ionized calcium at 0.69 mmol/L (1.15–1.29 mmol/L), and parathyroid hormone at < 1.0 pg/mL (12–88 pg/mL). Echocardiography revealed an ejection fraction of 28.48%. Cardiac function was quickly reversed by restoring the serum calcium concentration. Significant improvements were noted with an ejection fraction of up to 48.50% at follow-up.

For patients with potential hypocalcemia, monitoring calcium levels and dealing with hypocalcemia in time to avoid serious complications are important.

• Hypoparathyroidism
• Congestive heart failure
• Cardiomyopathy
• Parathyroid hormone
• Calcium
• Echocardiography
• Case report

Hypocalcemia is a rare, but reversible, cause of dilated cardiomyopathy. Although cardiomyopathy may cause severe heart failure, calcium supplementation can reverse heart failure. We report here a patient with uremia and secondary hyperparathyroidism, who was complicated by persistent hypocalcemia and refractory heart failure. The cardiac failure was refractory to treatment with digitalis and diuretics, but dramatically responded to calcium therapy and restoration of normocalcemia. As a result, the patient was eventually diagnosed with hypocalcemic cardiomyopathy. To the best of our knowledge, this is the first case of this disease to be reported in a patient with uremia. Findings from our case may help clinicians to better understand hypocalcemic cardiomyopathy. Our case might also provide new insight into long-term cardiac complications and prognoses of patients undergoing parathyroidectomy due to secondary hyperparathyroidism.

• Calcium
• heart failure
• hypocalcemic cardiomyopathy
• hypoparathyroidism
• hypotension
• secondary hyperparathyroidism
• uremia

Hypocalcaemic cardiomyopathy is a rare form of dilated cardiomyopathy. The authors here present two cases in which symptomatic dilated cardiomyopathy was the result of severe hypocalcaemia. First, we report about a 26‐year‐old woman with primary hypoparathyroidism and then about a 74‐year‐old man with secondary hypoparathyroidism following a thyroidectomy. In both cases, the left ventricular systolic function improved after calcium supplementation. In the first case, a lack of compliance led to a repeated decrease of both serum calcium level and left ventricular systolic function. The authors also present a comprehensive summary of all cases of hypocalcaemic dilated cardiomyopathy that have been described in literature to date. The mean age of the affected patients was 48.3 years, of which 62% were female patients. The most common causes of hypocalcaemic cardiomyopathy are primary hypoparathyroidism (50%) and post‐thyroidectomy hypoparathyroidism (26%). In the post‐thyroidectomy subgroup, the median time for the development of hypocalcaemic cardiomyopathy is 10 years (range: 1.5 months to 36 years). Hypocalcaemic cardiomyopathy leads to heart failure with reduced ejection fraction in 87% of patients. Generally, the most common complications of hypoparathyroidism and/or hypocalcaemia are cerebral calcifications, cognitive deficit, and cataracts. Once calcium supplementation is administered, the disease has a good prognosis and, in most individuals, a significant improvement (21%) or even normalization (74%) of the left ventricular systolic function occurs.

• Calcium
• Dilated cardiomyopathy
• Heart failure
• Hypocalcaemia
• Hypoparathyroidism
• Parathormone