Cardiovascular Involvement in Primary Hyperparathyroidism

Increased serum calcium with elevated or nonsuppressed PTH levels is the biochemical hallmark of primary hyperparathyroidism (PHPT). A large body of evidence linked both hypercalcemia and high serum levels of PTH with cardiovascular diseases, due to their actions on cardiomyocytes, endothelial, pancreatic β, and fat cells. However, controversial epidemiological data exist regarding the higher prevalence of hypertension, arrhythmias, dyslipidemia, echocardiographic, and vascular parameter impairments in PHPT patients compared to controls. Different cardiovascular risk factors related to sex, age groups, serum calcium levels, and different countries included in these studies cause conflicting results. Although current guidelines on hypercalcemic PHPT management do not suggest parathyroidectomy based on cardiovascular diseases, one meta-analysis showed improvement following parathyroidectomy for glucose metabolism and reduction of blood pressure. While structural cardiac changes such as left ventricular mass index was improved following parathyroidectomy in one but not in another meta-analysis, a more modern method that included global longitudinal strain measurement of left ventricular mass showed improvement following parathyroidectomy. An increased risk of major cerebrovascular or cardiovascular events in PHPT patients compared to controls has been reported in some but not all studies. Furthermore, meta-analyses are not always consistent in showing a higher risk of total and cardiovascular death in PHPT patients compared to the general population, as well as their reduction following parathyroidectomy. Robust randomized controlled studies are needed to definitively answer whether in patients with PHPT cardiovascular disease depend on serum calcium levels, PTH, or both, thus representing another new criterion to submit patients to surgery.