Myocardial Calcification due to Uncontrolled Hyperparathyroidism

Myocardial calcification: case reports and a systematic review

Aims

Myocardial calcification is an unusual condition in which excess calcium is deposited in the myocardium. Herein, we report two cases of myocardial calcification from our clinical experience. Furthermore, we conduct a systematic review to examine the clinical course and associated pathologies of myocardial calcification.

Methods and results

This systematic review was registered in PROSPERO (CRD42023463285). PubMed and Scopus were searched according to the following inclusion criteria: (i) case reports or case series describing patients with myocardial calcification; (ii) diagnosis of myocardial calcification by computed tomography (CT); (iii) adequate description of patients, including their chief complaint, medical history, evaluations, and treatments; and (iv) publication in English. Among the 75 patients, 24 had sepsis, 14 had myocarditis, and 37 had other pathologies. The mortality rate was 33% for patients with sepsis, 14% for patients with myocarditis, and 11% for patients with other pathologies. Follow-up CT findings beyond 2 years were reported in six patients, showing that the CT findings of myocardial calcification persisted but subsided over time. Autopsy was performed in seven patients, and extensive interstitial fibrosis and collection of inflammatory cells were observed in patients with myocarditis, sepsis, and ischaemic heart disease.

Conclusion

While various medical conditions can cause myocardial calcification, accompanying conditions commonly reported with myocardial calcification were sepsis and myocarditis. The CT findings of myocardial calcification tend to regress over time if the underlying disease can be treated.

A Novel Idiopathic Atrial Calcification: Pathologic Manifestations and Potential Mechanism

Background

Cardiac calcification is a type of ectopic pathologic calcification of unknown etiology and mechanisms. Once diagnosed, the location, extent and morphology of the calcified lesions, as well as their functional significance in the heart, are usually the focus of case reports. Calcification is mostly distributed in myocardium, but rarely reported in atrium. In addition, because of limited sampling and complex pathological mechanisms, the etiology underlying the formation of these calcified lesions also remains unclear.

Methods

Two cardiac calcifications were found in a patient, died of trauma-induced subarachnoid hemorrhage after slightly drinking, during a standard autopsy. The location and morphological characteristics of the calcified lesions were determined by computed tomography (CT) and CT-based 3D reconstruction. The specific histopathological characteristics of the lesions were determined by multi-staining. The concentration of free calcium and inorganic pyrophosphate (PPi) in plasma reflected the change of calcium metabolism. The expression and membranal localization of the ATP Binding Cassette Subfamily C Member 6 (ABCC6) in hepatocytes were detected by immunofluorescence. The variants of the ABCC6 were detected by Sanger sequencing and potential pathogenic variants were further identified by in silico analysis.

Results

The present study describes a patient with idiopathic calcification with two pear-shaped and irregularly hollow lesions symmetrically distributed in the patient's atrium. Massive accumulation of calcium salts was identified by multi-staining. For this patient, the plasma concentration of free calcium was higher than the control, indicating that calcium metabolism was disturbed. Furthermore, the plasma PPi of the patient was lower than the normal. By using immunofluorescence, the expression and membranal localization of ABCC6 was decreased and impaired in hepatocytes, respectively. Combined with Sanger sequencing and in silico analysis, 7 variants were identified.

Conclusions

This study described a novel patient with symmetrically distributed idiopathic atrial calcifications. Furthermore, all the results indicated that these pathologic calcifications may be secondary to reduced plasma PPi content due to ABCC6 dysfunction in hepatocytes. Moreover, these findings provided novel clues to the pathogenesis, clinical diagnosis and treatment of idiopathic atrial calcification in future.

Microwave ablation versus parathyroidectomy for severe secondary hyperparathyroidism in patients on hemodialysis: a retrospective multicenter study

BACKGROUND

Microwave ablation is effective for severe secondary hyperparathyroidism, but the difference in efficacy between microwave ablation and parathyroidectomy remains unclear. In this multicenter retrospective cohort study, we compared the long-term clinical efficacy of microwave ablation and parathyroidectomy for severe secondary hyperparathyroidism undergoing hemodialysis.

MATERIALS AND METHODS

The patients were divided into microwave ablation and parathyroidectomy groups. The primary endpoint was the proportion of patients with intact parathyroid hormone (iPTH) concentrations within the target range (100-600 pg/mL) during the efficacy assessment phase. The secondary endpoints were (i) differences in iPTH concentrations over time between the two groups, and (ii) decreases in iPTH concentrations over time in the two groups.

RESULTS

Microwave ablation was performed in 47/92 patients and parathyroidectomy in 45/92. Primary endpoint: iPTH concentrations within the target range were achieved during the efficacy assessment phase in 26/47 patients (55.3%) and in 14/45 (31.1%) patients in the microwave ablation and parathyroidectomy groups, respectively (p = .02). Secondary endpoints: (i) Mean iPTH concentrations during the efficacy assessment phase were significantly higher in the microwave ablation versus parathyroidectomy groups (649 ± 519 pg/mL versus 136 ± 228 pg/mL, respectively; p < .01). (ii) Mean decrease in iPTH concentration from baseline was 725 ± 605 pg/mL versus 1369 ± 478 pg/mL in the MWA versus parathyroidectomy groups, respectively (p < .01).

CONCLUSIONS

Ultrasound-guided percutaneous microwave ablation provides higher iPTH target-achieving rates than parathyroidectomy in patients with severe secondary hyperparathyroidism undergoing hemodialysis.