Fibroblast growth factor-23 and subclinical markers of cardiac dysfunction: The coronary artery risk development in young adults (CARDIA) study

Effect of surgical treatment on left ventricular strain in patients with primary hyperparathyroidism: A meta-analysis of echocardiographic study

AIM

Current evidence on the effects of parathyroidectomy (PTX) on myocardial deformation in patients with primary hyperparathyroidism (PHPT) is scanty and based on a few studies. The aim of this meta-analysis was to provide a comprehensive and updated information on this issue.

DATA SYNTHESIS

Following the PRISMA guidelines, systematic searches were conducted across bibliographic databases (Pub-Med, OVID, EMBASE and Cochrane library) to identify eligible studies from inception up to September 30th, 2024. Searches were limited to clinical investigations published in English reporting data on LV mechanics (i.e. global longitudinal strain, GLS) in patients with PHPT before and after PTX. The statistical difference of the echocardiographic variables of interest collected at baseline and after PTX, such as left ventricular ejection fraction (LVEF) and GLS was calculated by standardized mean difference (SMD) with 95 % confidence interval (CI) by using random-effects models. Four studies including 126 patients with PHPT undergoing PTX, in whom LV mechanics had been assessed by speckle tracking echocardiography before and after six months from surgery, were considered. Baseline pooled average LVEF values were 59.5 ± 1.7 % and corresponding values after PTX 60.3 ± 1.2 %, (SMD: 0.16 ± 0.09, CI: -0.01/0.34, p = 0.07). Baseline and after surgical procedure values for GLS were -18.9 ± 0.28 % and -20.4 + 0.28 %, (SMD: 0.55 ± 0.10, CI: 0.37/0.74, p < 0.001). Meta-regression analysis showed a significant relationship between changes in serum PTH and GLS (p = 0.004).

CONCLUSIONS

Our findings suggest that PTX impacts favourably on LV mechanics, and, more importantly, the assessment of LV changes in this setting should include GLS and no longer rely on conventional echocardiographic parameters such as LVEF.

Association of Fibroblast Growth Factor 23 and Cardiac Mechanics in the Cardiovascular Health Study

Key Points

Evaluation of cardiac mechanics through two-dimensional speckle tracking echocardiography can identify early alterations in cardiac function. In a subset of the Cardiovascular Health Study, c-terminal and intact fibroblast growth factor 23 were not independently associated with cardiac mechanic indices.

Background

Elevated levels of fibroblast growth factor 23 (FGF23) are associated with left ventricular hypertrophy and heart failure in individuals with and without kidney disease. Prior studies investigated the association of FGF23 and structural cardiac changes using conventional echocardiography, which is limited in its ability to detect early cardiac dysfunction. We investigated the relationship between FGF23 levels and cardiac dynamics using two-dimensional speckle tracking echocardiography (2D-STE), a novel imaging modality.

Methods

This was a cross-sectional analysis of data from the Cardiovascular Health Study (CHS), an ongoing prospective, population-based cohort study. The study population included 506 participants from CHS with available c-terminal FGF23 (cFGF23) and intact FGF23 (iFGF23) measurements from 1996 to 1997 and 2D-STE images from 1994 to 1995. Forty-two percent of the study population had CKD, defined as an eGFR <60 ml/min per 1.73 m2, and the mean eGFR was 63 ml/min per 1.73 m2. The primary exposures were cFGF23 and iFGF23. The primary outcomes were six 2D-STE parameters performed at the 1994–1995 study visit. Linear regression models were used to examine the independent associations of FGF23 with six cardiac 2D-STE indices adjusting for demographics, cardiovascular risk factors, markers of kidney disease severity, and inflammation.

Results

cFGF23 levels were moderately correlated with iFGF23 levels in the CHS population. In fully adjusted models, cFGF23 was associated with left atrial dysfunction, but no other cardiac imaging parameter (β estimate, −2.47; 95% confidence interval, −4.68 to −0.25; Table 2 ). iFGF23 was not associated with any of the six 2D-STE indices. Limitations include small sample size and noncurrent FGF23 measurements and 2D-STE imaging.

Conclusions

In a limited sample of individuals enrolled in the CHS with cFGF23 and iFGF23 measurements, we did not find consistent associations between FGF23 levels and 2D-STE parameters. Further investigations in a larger population with concurrent 2D-STE are needed to better understand the associations of FGF23 with early changes in cardiac mechanics.

The bone-heart axis in the pathogenesis of cardiovascular diseases: A narrative review

Cardiovascular diseases (CVDs) cause about 30% of deaths worldwide, increasing social and economic burden in our societies. Although the treatment of the canonical cardiovascular risk factors has reduced the impact of CVDs on morbidity and mortality in the past few years, they continue to represent a major health problem. The definition of the biological properties of the bone-heart axis has led to new insights in the pathogenesis of CVDs; hence, the aim of this review is to try to elucidate the role of this axis on the susceptibility to CVDs. There is evidence that the bone interacts with extra-skeletal organs, including the cardiovascular system, through its endocrine functions. Clinical and experimental data strongly indicate that the interplay between the bone and the cardiovascular system represents a future tool for the prevention, diagnosis and treatment of CVDs. The identification of these non-canonical cardiovascular risk factors could prompt pharmacological research towards new target therapy aimed at precision medicine.

FGF23 and klotho at the intersection of kidney and cardiovascular disease

Cardiovascular disease is the leading cause of death in patients with chronic kidney disease (CKD). As CKD progresses, CKD-specific risk factors, such as disordered mineral homeostasis, amplify traditional cardiovascular risk factors. Fibroblast growth factor 23 (FGF23) regulates mineral homeostasis by activating complexes of FGF receptors and transmembrane klotho co-receptors. A soluble form of klotho also acts as a 'portable' FGF23 co-receptor in tissues that do not express klotho. In progressive CKD, rising circulating FGF23 levels in combination with decreasing kidney expression of klotho results in klotho-independent effects of FGF23 on the heart that promote left ventricular hypertrophy, heart failure, atrial fibrillation and death. Emerging data suggest that soluble klotho might mitigate some of these effects via several candidate mechanisms. More research is needed to investigate FGF23 excess and klotho deficiency in specific cardiovascular complications of CKD, but the pathophysiological primacy of FGF23 excess versus klotho deficiency might never be precisely resolved, given the entangled feedback loops that they share. Therefore, randomized trials should prioritize clinical practicality over scientific certainty by targeting disordered mineral homeostasis holistically in an effort to improve cardiovascular outcomes in patients with CKD.

Zebrafish as a Model of Cardiac Pathology and Toxicity: Spotlight on Uremic Toxins

Chronic kidney disease (CKD) is an increasing health care problem. About 10% of the general population is affected by CKD, representing the sixth cause of death in the world. Cardiovascular events are the main mortality cause in CKD, with a cardiovascular risk 10 times higher in these patients than the rate observed in healthy subjects. The gradual decline of the kidney leads to the accumulation of uremic solutes with a negative effect on every organ, especially on the cardiovascular system. Mammalian models, sharing structural and functional similarities with humans, have been widely used to study cardiovascular disease mechanisms and test new therapies, but many of them are rather expensive and difficult to manipulate. Over the last few decades, zebrafish has become a powerful non-mammalian model to study alterations associated with human disease. The high conservation of gene function, low cost, small size, rapid growth, and easiness of genetic manipulation are just some of the features of this experimental model. More specifically, embryonic cardiac development and physiological responses to exposure to numerous toxin substances are similar to those observed in mammals, making zebrafish an ideal model to study cardiac development, toxicity, and cardiovascular disease.

Direct and indirect effects of fibroblast growth factor 23 on the heart

Fibroblast growth factor (FGF)23 is a bone-derived phosphotropic hormone that regulates phosphate and mineral homeostasis. Recent studies have provided evidence that a high plasma concentration of FGF23 is associated with cardiac disease, including left ventricular hypertrophy (LVH), heart failure, atrial fibrillation, and cardiac death. Experimental studies have shown that FGF23 activates fibroblast growth factor receptor 4 (FGFR4)/phospholipase Cγ/calcineurin/nuclear factor of activated T-cells signaling in cardiomyocytes and induces cardiac hypertrophy in rodents. Activation of FGFR4 by FGF23 normally requires the co-receptor α-klotho, and klotho-independent signaling occurs only under conditions characterized by extremely high FGF23 concentrations. Recent studies have demonstrated that FGF23 activates the renin-angiotensin-aldosterone system (RAAS) and induces LVH, at least in part as a result of lower vitamin D activation. Moreover, crosstalk between FGF23 and RAAS results in the induction of cardiac hypertrophy and fibrosis. In this review, we summarize the results of studies regarding the relationships between FGF23 and cardiac events, and describe the potential direct and indirect mechanisms whereby FGF23 induces LVH.

Novel Biomarkers of Kidney Disease in Advanced Heart Failure: Beyond GFR and Proteinuria

PURPOSE

Kidney disease is a common finding in patients with heart failure and can significantly impact treatment decisions and outcomes. Abnormal kidney function is currently determined in clinical practice using filtration markers in the blood to estimate glomerular filtration rate, but the manifestations of kidney disease in the setting of heart failure are much more complex than this. In this manuscript, we review novel biomarkers that may provide a more well-rounded assessment of kidney disease in patients with heart failure.

RECENT FINDINGS

Galectin-3, ST2, FGF-23, suPAR, miRNA, GDF-15, and NAG may be prognostic of kidney disease progression. L-FABP and suPAR may help predict acute kidney injury (AKI). ST2 and NAG may be helpful in diuretic resistance. Several biomarkers may be useful in determining prognosis of long-term kidney disease progression, prediction of AKI, and development of diuretic resistance. Further research into the mechanisms of kidney disease in heart failure utilizing many of these biomarkers may lead to the identification of therapeutic targets.