Arrhythmias in primary hyperparathyroidism evaluated by exercise test

Twenty-four hour Holter ECG in normocalcemic and hypercalcemic patients with hyperparathyroidism

PURPOSE

To investigate the occurrence of arrhythmias in patients with normocalcemic (NC) primary hyperparathyroidism (PHPT) compared to both hypercalcemic PHPT patients and control subjects by means of 24-h Holter ECG.

METHODS

Thirteen NCPHPT postmenopausal patients were enrolled and age-matched with 13 hypercalcemic PHPT patients and 13 controls. Every subject underwent basal ECG, 24-h Holter ECG and mineral metabolism biochemical evaluation.

RESULTS

PHPT patients had higher mean serum calcium levels compared to both NCPHPT and controls; there was no difference in mean serum calcium levels between NCPHPT and controls. Both NCPHPT and PHPT patients had significantly higher mean PTH levels compared with controls. There were no differences in ECG parameters between the three groups, except for QTc interval. PHPT patients had normal QTc interval values, but significantly shorter mean values compared with those of controls and NCPHPT patients. During 24-h Holter ECG recording, 100% of PHPT patients had supraventricular premature beats (SVPBs), compared to 46% of NCPHPT (p = 0.005) and to 53% of controls (p = 0.01). PHPT patients experienced ventricular premature beats (VPBs) (69.2%) vs 15% of NCPHPT patients (p = 0.01) and 23% of controls (p = 0.04). There was no difference between NCPHPT and controls subjects concerning occurrence of both VPBs and SVPBs.

CONCLUSIONS

NCPHPT patients did not experience an increased occurrence of arrhythmias compared to controls, while PHPT patients showed an increased occurrence compared to both controls and NCPHPT. Our findings are most probably related to the short QTc interval caused by hypercalcemia observed in PHPT patients, but not in NCPHPT.

Cinacalcet Reverses Short QT Interval in Familial Hypocalciuric Hypercalcemia Type 1

CONTEXT

Familial hypocalciuric hypercalcemia type 1 (FHH-1) defines an autosomal dominant disease, related to mutations in the CASR gene, with mild hypercalcemia in most cases. Cases of FHH-1 with a short QT interval have not been reported to date.

OBJECTIVE

Three family members presented with FHH-1 and short QT interval (<360 ms), a condition that could lead to cardiac arrhythmias, and the effects of cinacalcet, an allosteric modulator of the CaSR, in rectifying the abnormal sensitivity of the mutant CaSR and in correcting the short QT interval were determined.

METHODS

CASR mutational analysis was performed by next-generation sequencing and functional consequences of the identified CaSR variant (p.Ile555Thr), and effects of cinacalcet were assessed in HEK293 cells expressing wild-type and variant CaSRs. A cinacalcet test consisting of administration of 30 mg cinacalcet (8 Am) followed by hourly measurement of serum calcium, phosphate, and parathyroid hormone during 8 hours and an electrocardiogram was performed.

RESULTS

The CaSR variant (p.Ile555Thr) was confirmed in all 3 FHH-1 patients and was shown to be associated with a loss of function that was ameliorated by cinacalcet. Cinacalcet decreased parathyroid hormone by >50% within two hours, and decreases in serum calcium and increases in serum phosphate occurred within 8 hours, with rectification of the QT interval, which remained normal after 3 months of cinacalcet treatment.

CONCLUSION

Our results indicate that FHH-1 patients should be assessed for a short QT interval and a cinacalcet test used to select patients who are likely to benefit from this treatment.

Nontraditional Aspects of Sporadic Primary Hyperparathyroidism

Nontraditional aspects of primary hyperparathyroidism refer to the condition's rheumatic, gastrointestinal, cardiovascular, and neuropsychological effects. Although gastrointestinal and rheumatic symptomatology were features of classical primary hyperparathyroidism, they do not seem to be a part of the modern presentation of primary hyperparathyroidism. In contrast, neuropsychological symptoms such as altered mood and cognition, as well as cardiovascular disease, have been associated with the form of primary hyperparathyroidism seen today, but the relationship is not clearly causal. Evidence does not support reversibility after parathyroidectomy and therefore none of the nontraditional manifestations are considered sole indications for recommending surgery at this time.

Impact of parathyroidectomy on cardiovascular risk in primary hyperparathyroidism: A narrative review

AIMS

Primary hyperparathyroidism (PHPT), one of the most frequent endocrine disorders, is not only associated with bone and kidney disorders but also with increased cardiovascular risk. This cardiovascular risk is not part of the indication for surgery owing to discordant evidence of the effects of parathyroidectomy (PTX), especially in mild PHPT which is the most common presentation of PHPT. This literature review focuses on the effects of PTX on the cardiovascular risk in PHPT. The MEDLINE database was searched via the PubMed interface, selecting relevant articles published after 1990 in English.

DATA SYNTHESIS

In the most recent series, PTX appeared to have a positive impact on cardiovascular morbidity and mortality. Surgery improves arterial hypertension, markers of glucose homeostasis, vascular and cardiac remodeling and electrocardiographic impairments due to classical PHPT. However, the results of surgery on mild PHPT are conflicting.

CONCLUSIONS

PTX seems to improve cardiovascular risk in patients presenting the classical form of PHPT. This improvement is correlated with preoperative serum calcium and/or PTH level, depending on the cardiovascular risk factor. However, many aspects of this improvement are not fully understood. Future studies should assess the effects of PTX on nocturnal hypertension, cardiac morphology and functions. The results for mild PHPT are conflicting owing to the limited size of the cohorts included in studies and the lack of randomized trials. Surgery is not currently recommended for patients presenting mild PHPT based on the cardiovascular risk and more studies are needed to better understand the interest of PTX on cardiovascular outcomes.

ECHOCARDIOGRAPHIC FINDINGS IN PATIENTS WITH NORMOCALCEMIC PRIMARY HYPERPARATHYROIDISM COMPARED WITH FINDINGS IN HYPERCALCEMIC PRIMARY HYPERPARATHYROID PATIENTS AND CONTROL SUBJECTS

OBJECTIVE

There are no data regarding echocardiographic parameters in patients with normocalcemic primary hyperparathyroidism (NCPHPT). We compared the echocardiographic findings in postmenopausal women with NCPHPT with those in patients with hypercalcemic primary hyperparathyroidism (PHPT) and controls.

METHODS

Seventeen consecutive Caucasian postmenopausal women with NCPHPT were compared with 20 women with hypercalcemic PHPT and 20 controls. Obesity, diabetes, kidney failure, and previous cardiovascular diseases were considered exclusion criteria. Each patient underwent biochemical evaluation, bone mineral density scan, and echocardiographic measurements. Patients with parathyroid disorders underwent kidney ultrasound evaluation.

RESULTS

Patients with PHPT had significantly higher mean total serum calcium, ionized calcium, 24-hour urinary calcium, and parathyroid hormone and lower mean phosphorus levels compared with those in the controls (all P < .05). The only differences between patients with NCPHPT and PHPT were significantly lower mean total serum calcium, ionized calcium, and 24-hour urinary calcium and higher phosphorus levels in patients with NCPHPT (all P < .05). The only biochemical difference between patients with NCPHPT and the controls was a higher level of mean parathyroid hormone in patients with NCPHPT. There were no differences in cardiovascular risk factors between patients with NCPHPT and PHPT and the controls. Hypertension was the most frequent cardiovascular risk factor, diagnosed in 65% of patients with PHPT. This high prevalence was not statistically significant compared with that observed in patients with NCPHPT (59%) and in the controls (30%). Echocardiography parameters were not different between patients with NCPHPT and PHPT and the controls when subdivided according to the presence of hypertension (ANOVA followed by Bonferroni correction).

CONCLUSION

In a population with a low cardiovascular risk, we found no differences in cardiovascular risk factors and echocardiographic parameters between patients with NCPHPT and PHPT and the controls.

Serum parathyroid hormone levels in patients with chronic right heart failure

Parathyroid hormone (PTH) is a novel cardiovascular biomarker which is particularly useful for detection and assessment of heart failure (HF). However, previous studies examining PTH in heart failure have primarily focused on left HF; thus, the relationship between PTH and right HF remains unclear. The aim of the present study was to evaluate the serum PTH levels in patients with chronic right HF. A total of 154 patients with chronic right HF were enrolled in the present study. A binary logistic regression analysis model was used to assess the independent predictive value of PTH levels in chronic right HF. Partial correlative analysis was used to demonstrate the relevance of PTH levels on the parameters of assessment of right heart function. A multiple linear regression analysis model was used to evaluate the independent factors of PTH levels in patients with right HF. The results showed that the serum PTH levels in the right HF group were significantly higher compared with the control group. After adjusting for predictors of right HF, serum PTH levels were associated with right HF with an odds ratio of 1.066 (95% confidence interval: 1.030-1.102, P<0.001. Serum PTH levels were independently correlated with plasma N-terminal pro-B-type natriuretic peptide levels, right ventricular end-diastolic diameter and severity of lower extremity edema (all P<0.05). Therefore, based on the results of the present study, PTH may be a useful biomarker for detection and assessment of right HF.

Non classical complications of primary hyperparathyroidism

Several studies suggested that the condition of primary hyperparathyroidism (PHPT) may be associated not only with the classical bone, kidney and gastrointestinal consequences, but also with cardiovascular, neuromuscular and articular complications, impaired quality of life and increased cancer risk. However, the only cardiovascular complications associated with PHPT, which seems to improve after parathyroidectomy, is left ventricular hypertrophy, while, data regarding the reversibility of hypertension, valve calcifications and increased vascular stiffness are inconsistent. Parathyroidectomy seems to ameliorate neuropsychological, cognitive disturbances and quality of life in moderate-severe PHPT, while data in mild PHPT are less clear. At variance, the effect of parathyroidectomy on neuromuscular and articular complications is still unknown, and no studies demonstrated a reduction of cancer risk after recovery from PHPT. Overall, to date, cardiovascular and neuropsychological evaluation are not recommended solely because of PHPT, nor cardiovascular disease, muscle weakness, and neuropsychological complications are indication for parathyroidectomy.

Reduction of arrhythmias in primary hyperparathyroidism, by parathyroidectomy, evaluated with 24-h ECG monitoring

OBJECTIVE

Hypercalcemia may induce arrhythmias. There are no data on the prevalence of arrhythmias in primary hyperparathyroidism (PHPT) in daily life. Aim of the study was to investigate both the prevalence of arrhythmias in patients with PHPT compared to controls and the impact of parathyroidectomy, evaluated by 24-h electrocardiogram (ECG) monitoring.

DESIGN

This is a randomized study.

METHODS

Twenty-six postmenopausal women with PHPT and 26 controls were enrolled. PHPT patients were randomized to two groups: 13 underwent parathyroidectomy (Group A) and 13 were followed up conservatively (Group B). After 6 months, patients were studied again. Each patient underwent mineral metabolism biochemical evaluation, bone mineral density measurement, standard ECG and 24-h ECG monitoring.

RESULTS

PHPT patients showed higher calcium and parathyroid hormone compared to controls and a higher prevalence of both supraventricular (SVBPs) and ventricular premature beats (VPBs) during 24-h ECG monitoring. Groups A and B showed no differences in mean baseline biochemical values and ECG parameters. Mean value of QTc in PHPT groups was in the normal range at baseline, but significantly shorter than controls. A negative correlation was found between QTc and ionized calcium levels (r = -0.48, P < 0.05). After parathyroidectomy, Group A had a significant reduction in SVPBs and VPBs compared to baseline and restored normal QTc. Group B showed no significant changes after a 6-month period.

CONCLUSIONS

The increased prevalence of SVPBs and VPBs is significantly reduced by parathyroidectomy, and it is mainly related to the short QTc caused by hypercalcemia.

Cardiovascular manifestations of primary hyperparathyroidism: a narrative review

Data on cardiovascular disease in primary hyperparathyroidism (PHPT) are controversial; indeed, at present, cardiovascular involvement is not included among the criteria needed for parathyroidectomy. Aim of this narrative review is to analyze the available literature in an effort to better characterize cardiovascular involvement in PHPT. Due to physiological effects of both parathyroid hormone (PTH) and calcium on cardiomyocyte, cardiac conduction system, smooth vascular, endothelial and pancreatic beta cells, a number of data have been published regarding associations between symptomatic and mild PHPT with hypertension, arrhythmias, endothelial dysfunction (an early marker of atherosclerosis), glucose metabolism impairment and metabolic syndrome. However, the results, mainly derived from observational studies, are inconsistent. Furthermore, parathyroidectomy resulted in conflicting outcomes, which may be linked to several potential biases. In particular, differences in the methods utilized for excluding confounding co-existing cardiovascular risk factors together with differences in patient characteristics, with varying degrees of hypercalcemia, may have contributed to these discrepancies. The only meta-analysis carried out in PHPT patients, revealed a positive effect of parathyroidectomy on left ventricular mass index (a predictor of cardiovascular mortality) and more importantly, that the highest pre-operative PTH levels were associated with the greatest improvements. In normocalcemic PHPT, it has been demonstrated that cardiovascular risk factors are almost similar compared to hypercalcemic PHPT, thus strengthening the role of PTH in the cardiovascular involvement. Long-term longitudinal randomized trials are needed to determine the impact of parathyroidectomy on cardiovascular diseases and mortality in PHPT.

Risk Factors for Intraoperative Hypertension during Surgery for Primary Hyperparathyroidism

OBJECTIVE

To investigate the incidence and identify risk factors for the occurrence of intraoperative hypertension (IOH) during surgery for primary hyperparathyroidism (pHPT).

SUBJECTS AND METHODS

The study included 269 patients surgically treated between January 2008 and January 2012 for pHPT. IOH was defined as an increase in systolic blood pressure ≥20% compared to baseline values which lasted for 15 min. The investigated influence were demographic characteristics, surgical risk score related to physical status (based on the American Society of Anesthesiologists [ASA] classification), comorbidities, type and duration of surgery, and duration of anesthesia on IOH occurrence. The investigated factors were obtained from the patients' medical history, anesthesia charts, and the daily practice database. Logistic regression analysis was done to determine the predictors of IOH.

RESULTS

Of the 269 patients, 153 (56.9%) had IOH. Based on the univariate analysis, age, body mass index, ASA status, duration of anesthesia, and preoperative hypertension were risk factors for the occurrence of IOH. Multivariate analysis showed that independent predictors of IOH were a history of hypertension (OR = 2.080, 95% CI: 1.102-3.925, p = 0.024) and age (OR = 0.569, 95% CI: 0.360-0.901, p = 0.016).

CONCLUSION

In this study, a high percentage (56%) of the patients developed IOH during surgery for pHPT, which indicates that special attention should be paid to these patients, especially to the high-risk groups: older patients and those with a history of hypertension. Further, this study showed that advanced age and hypertension as a coexisting disease prior to parathyroid surgery were independent risk factors for the occurrence of IOH.

High prevalence of abdominal aortic calcification in patients with primary hyperparathyroidism as evaluated by Kauppila score

OBJECTIVE

The prevalence of abdominal aortic calcification (AAC) in primary hyperparathyroidism (PHPT) is unknown. We assessed both prevalence and severity of AAC in PHPT postmenopausal women.

METHODS

In this study 70 PHPT postmenopausal women and 70 age- and sex-matched controls were enrolled. Each participant underwent biochemical evaluation, lateral spine radiograph, bone mineral density (BMD) measurement (lumbar, femoral, radial sites), and kidney ultrasound. Lateral lumbar films were analyzed in the region of L1-L4 vertebrae and the Kauppila score (a semi-quantitative grading system) was used to assess the severity of AAC.

RESULTS

There were no differences regarding demographic and cardiovascular risk factors in the two groups. PHPT patients had higher prevalence of kidney stones (30% vs 7%, P=0.0008) and lower radial BMD values (0.558±0.071 vs 0.588±0.082 g/cm(2), P<0.05) compared with controls. PHPT patients showed higher prevalence of AAC (31 vs 18, P=0.03), with more severe calcifications (Kauppila score 7.35±6.1 vs 5.05±3.5, P=0.007). PHPT patients with AAC were older and had been suffering from the disease for a longer period compared with those without ACC. Moreover, PHPT patients with severe AAC had mean higher serum parathyroid hormone levels compared with patients with moderate or mild calcifications. In PHPT patients with AAC, multiple regression analysis, adjusted for age and years since diagnosis, showed that only parathyroid hormone significantly correlated with Kauppila score.

CONCLUSION

We found a higher prevalence and severity of AAC in PHPT related to parathyroid hormone effect.

Quality of life in patients with primary hyperparathyroidism

The clinical picture of primary hyperparathyroidism (PHPT) has changed over the last three decades and many asymptomatic patients are now diagnosed through the unexpected finding of high serum calcium levels. However, though not yet considered as typical features of the disease and therefore not included in the guidelines for surgery, many data are available on neuropsycological manifestations and their impact on quality of life in asymptomatic patients. PHPT patients indeed show early experience nonspecific symptoms, such as weakness, depression, sleep disturbance, memory loss and anxiety. Although the underlining mechanisms have not been still identified, the prevalence of psychiatric and cognitive deficits has been investigated in many studies, as well as the possible association with quality of life and well-being improvement after surgery. This article aims to review the current knowledge on quality of life in PHPT patients before and after surgery and the possible clinical implications of these findings.

Sporadic primary hyperparathyroidism: medical and surgical updates

This review discusses recent findings on the clinical presentation, evaluation, medical and surgical management of primary hyperparathyroidism. Medical management includes the use of cinacalcet and bisphosphonates for bone loss and correction of vitamin D deficiency. Surgical updates reviewed recent studies on the preoperative localization of the disease, specifically, sestamibi scans, 4DCT and MRI. Focused parathyroidectomy continues to be the preferred surgical approach for a select group of patients, guided by intraoperative use of PTH and new technology, such as endoscopic and robotic platforms; however, there appears to be no difference in long-term success compared to the traditional approach.

Parathyroidectomy eliminates arrhythmic risk in primary hyperparathyroidism, as evaluated by exercise test

OBJECTIVE

To investigate whether parathyroidectomy (PTx) reverses risk factors for arrhythmias related to the QT dynamic changes evaluated during bicycle ergometry exercise test (ET).

METHODS

Twenty-four postmenopausal women with primary hyperparathyroidism (PHPT) (mean age 60.08.4 years) and 30 sex- and age-matched controls underwent ET, echocardiography, and biochemical evaluation. The following stages were considered during ET: rest, peak exercise, and recovery. The patients were randomized to two groups: 12 underwent PTx (group A) and 12 were followed-up conservatively (group B). After 6 months, the patients were studied again.

RESULTS

Groups A and B showed no differences in mean baseline biochemical values, echocardiographic parameters, and QTC interval. PHPT patients showed an increased occurrence of ventricular premature beats (VPBS) during ET compared with controls (37.0 vs 6.6%, P=0.03). Serum calcium level was a predictor of VPBS (P=0.05). Mean value of QTC was in the normal range at baseline (Group A: 401±16.9; group B: 402.25±13.5 ms) but significantly lower than controls (417.8±25.1 ms, P<0.01). A negative correlation was found between QTc and calcium values (P=0.03). Physiological reduction of QTc interval from rest to peak exercise was not observed in PHPT patients before surgery. After PTx, group A had a significant reduction in VPBs compared with baseline (at baseline, 5 of 12 vs none of 12 patients after PTx, P=0.03) and a restored normal QT adaptation during ET. Group B showed no significant changes after a 6-month period.

CONCLUSIONS

PTx reduces the occurrence of VPBs and restored the QTc adaptation during ET.