Association of inflammatory, lipid and mineral markers with cardiac calcification in older adults

Rethinking Mitral Annular Calcification and Its Clinical Significance: From Passive Process to Active Pathology

BACKGROUND

Mitral annulus calcification is a chronic degenerative condition affecting the fibrous base of the mitral valve. Historically viewed as an age-related phenomenon, recent studies suggest it is driven by active mechanisms involving systemic inflammation, hemodynamic stress, abnormal calcium-phosphorus metabolism, and lipid accumulation. Despite often being asymptomatic and incidentally detected, its clinical relevance stems from its strong association with increased cardiovascular disease risk, higher cardiovascular mortality, and elevated overall mortality.

METHODS

This article investigates the complexities and controversies surrounding mitral annular calcification as a potential embolic source, focusing on its diagnosis, its relationship with systemic inflammation, and its links to metabolic and chronic disorders.

RESULTS

The findings highlight that mitral annular calcification is not merely a passive marker of aging but an active indicator of atherosclerotic burden with significant implications for cardiovascular health.

CONCLUSION

Mitral annulus calcification should be recognized as an important factor in cardiovascular risk assessment, offering insight into systemic inflammatory processes and metabolic dysregulation.

Differential biomarker expression in heart failure patients with and without mitral regurgitation: Insights from BIOSTAT-CHF

BACKGROUND

Mitral regurgitation (MR) frequently coexists with heart failure (HF).

OBJECTIVES

To better understand potential pathophysiological differences between patients with HF with or without moderate-severe MR, we compared differentially expressed circulating biomarkers between these two groups.

METHODS

The Olink Proteomics® Multiplex Cardiovascular (CVD) -II, CVD-III, Immune Response and Oncology-II panels of 363 unique proteins from different pathophysiological domains were used to investigate the biomarker profiles of HF patients from index and validation cohorts of the BIOSTAT-CHF study stratified according to the presence of moderate-to-severe MR or no-mild MR.

RESULTS

The index cohort included 888 patients (46%) with moderate-to-severe MR and 1029 (54%) with no-mild MR at baseline. The validation cohort included 522 patients (33%) with moderate-to-severe MR and 1076 (66%) with no-mild MR at baseline. Compared to patients with no-mild MR, those with moderate-to-severe MR had lower body mass index, higher comorbidity burden, signs and symptoms of more severe HF, lower systolic blood pressure, and larger left atrial and ventricular dimensions, in both cohorts. NT-proBNP, CA125, fibroblast growth factor 23 (FGF23) and growth hormone 1 (GH1) were up-regulated, whereas leptin (LEP) was down-regulated in patients with moderate-severe MR versus no-mild MR, in both index and validation cohorts.

CONCLUSION

Circulating biomarkers differently expressed in HF patients with moderate-severe MR versus no-mild MR were related to congestion, lipid and mineral metabolism and oxidative stress. These findings may be of value for the development of novel treatment targets in HF patients with MR.

Traditional and novel risk factors for incident aortic stenosis in community-dwelling older adults

OBJECTIVES

Calcific aortic stenosis (AS) is the most common valvular disease in older adults, yet its risk factors remain insufficiently studied in this population. Such studies are necessary to enhance understanding of mechanisms, disease management and therapeutics.

METHODS

The Cardiovascular Health Study is a population-based investigation of older adults that completed adjudication of incident AS over long-term follow-up. We evaluated traditional cardiovascular risk factors or disease, as well as novel risk factors from lipid, inflammatory and mineral metabolism pathways, in relation to incident moderate or severe AS (including AS procedures) and clinically significant AS (severe AS, including procedures).

RESULTS

Of 5390 participants (age 72.9±5.6 years, 57.6% female, 12.5% black), 287 developed moderate or severe AS, and 175 clinically significant AS, during median follow-up of 13.1 years. After full adjustment, age (HR=1.66 per SD (95% CI=1.45, 1.91)), male sex (HR=1.41 (1.06, 1.87)), diabetes (HR=1.53 (1.10, 2.13)), coronary heart disease (CHD, HR=1.36 (1.01, 1.84)), lipoprotein-associated phospholipase-A2 (LpPLA2) activity (HR=1.21 per SD (1.07, 1.37)) and sCD14 (HR=1.16 per SD (1.01, 1.34)) were associated with incident moderate/severe AS, while black race demonstrated an inverse association (HR=0.40 (0.24, 0.65)), and creatinine-based estimated glomerular filtration rate (eGFRcr) showed a U-shaped relationship. Findings were similar for clinically significant AS, although CHD and sCD14 fell short of significance, but interleukin-(IL) 6 showed a positive association.

CONCLUSION

This comprehensive evaluation of risk factors for long-term incidence of AS identified associations for diabetes and prevalent CHD, LpPLA2 activity, sCD14 and IL-6, and eGFRcr. These factors may hold clues to biology, preventive efforts and potential therapeutics for those at highest risk.

Fetuin-A levels in association with calcific aortic valve disease: A meta-analysis

Background and aims

Calcific aortic valve disease (CAVD) is a common valvular disease, prevalent particularly within the older age groups. The potential use of biomarkers in diagnosing and assessing the severity of CAVD, in supplementation with imaging techniques, has recently gained momentum within the field of cardiovascular medicine. Therefore, a meta-analysis was performed that assessed the association between the fetuin-A levels, and the presence of CAVD.

Methods

PubMed and Cochrane were searched from inception to April 2023. Risk of bias was assessed using the Newcastle-Ottawa scale for cohort studies.

Results

This analysis includes a total of 3,280 patients with CAVD, and 7,505 patients as control, resulting in the pooling of 10,785 patients in this meta-analysis. It was observed that the circulating levels of fetuin-A were significantly lowered in patients with CAVD (SMD: -0.20; 95% CI: -0.39, -0.02; P = 0.03). Moreover, the analysis revealed that fetuin-A levels had no significant association with CAVD in patients suffering from kidney disease (SMD: 0.20; 95% CI: -0.46, 0.85; P = 0.56).

Conclusion

While initial results demonstrate the potential effectiveness, further research is essential in order to arrive at a robust conclusion regarding the use of fetuin-A as a diagnostic biomarker for calcific aortic valve disease.

High lipoprotein(a) levels and mitral valve disease: A systematic review

AIMS

The role of lipoprotein(a) [Lp(a)] as a possibly causal risk factor for atherosclerotic artery disease and aortic valve stenosis has been well established. However, the information available on the association between Lp(a) levels and mitral valve disease is limited and controversial. The main objective of the present study was to assess the association between Lp(a) levels and mitral valve disease.

DATA SYNTHESIS

This systematic review was performed according to PRISMA guidelines (PROSPERO CRD42022379044). A literature search was performed to detect studies that evaluated the association between Lp(a) levels or single-nucleotide polymorphisms (SNPs) related to high levels of Lp(a) and mitral valve disease, including mitral valve calcification and valve dysfunction. Eight studies including 1,011,520 individuals were considered eligible for this research. The studies that evaluated the association between Lp(a) levels and prevalent mitral valve calcification found predominantly positive results. Similar findings were reported in two studies that evaluated the SNPs related to high levels of Lp(a). Only two studies evaluated the association of Lp(a) and mitral valve dysfunction, showing contradictory results.

CONCLUSIONS

This research showed disparate results regarding the association between Lp(a) levels and mitral valve disease. The association between Lp(a) levels and mitral valve calcification seems more robust and is in line with the findings already demonstrated in aortic valve disease. New studies should be developed to clarify this topic.

The Associations of Aortic Valve Sclerosis, Aortic Annular Increased Reflectivity, and Mitral Annular Calcification with Subsequent Aortic Stenosis in Older Individuals: Findings from the Cardiovascular Health Study

BACKGROUND

Although aortic valve sclerosis (AVS) is well described as preceding aortic stenosis (AS), the associations of AS with antecedent mitral annular calcification (MAC) and aortic annular increased reflectivity (AAIR) have not been characterized. In a population-based prospective study, the authors evaluated whether MAC, AAIR, and AVS are associated with the risk for incident AS.

METHODS

Among participants of the Cardiovascular Health Study free of AS at the 1994-1995 visit, the presence of MAC, AAIR, AVS, and the combination of all three was evaluated in 3,041 participants. Cox proportional-hazards regression was used to assess the association between the presence of calcification and the incidence of moderate or severe AS in three nested models adjusting for factors associated with atherosclerosis and inflammation both relevant to the pathogenesis of AS.

RESULTS

Over a median follow-up period of 11.5 years (interquartile range, 6.7-17.0 years), 110 cases of incident moderate or severe AS were ascertained. Strong positive associations with incident moderate or severe AS were found for all calcification sites after adjustment for the main model covariates: AAIR (hazard ratio [HR], 2.90; 95% CI, 1.95-4.32; P < .0005), AVS (HR, 2.20; 95% CI, 1.44-3.37; P < .0005), MAC (HR, 1.67; 95% CI, 1.14-2.45; P = .008), and the combination of all three (HR, 2.50; 95% CI, 1.65-3.78; P < .0005). In a secondary analysis, the risk for AS increased with the number of sites at which calcification was present.

CONCLUSIONS

In a large cohort of community-dwelling elderly individuals, there were strong associations between each of AAIR, AVS, MAC, and the combination of the three and incident moderate or severe AS. The novel finding that AAIR had a particularly strong association with incident AS, even after adjusting for other calcification sites, suggests its value in identifying individuals at risk for AS and potential inclusion in routine assessment by transthoracic echocardiography.

High-Density Lipoprotein and Long-Term Incidence and Progression of Aortic Valve Calcification: The Multi-Ethnic Study of Atherosclerosis

BACKGROUND

Aortic valve calcification (AVC) shares pathological features with atherosclerosis. Lipoprotein components have been detected in aortic valve tissue, including HDL (high-density lipoprotein). HDL measures have inverse associations with cardiovascular disease, but relationships with long-term AVC progression are unclear. We investigated associations of HDL cholesterol, HDL-particle number and size, apoC3-defined HDL subtypes, and, secondarily, CETP (cholesteryl ester transfer protein) mass and activity, with long-term incidence and progression of AVC.

METHODS

We used linear mixed-effects models to evaluate the associations of baseline HDL indices with AVC. AVC was quantified by Agatston scoring of up to 3 serial computed tomography scans over a median of 8.9 (maximum 11.2) years of follow-up in the Multi-Ethnic Study of Atherosclerosis (n=6784).

RESULTS

After adjustment, higher concentrations of HDL-C (high-density lipoprotein cholesterol), HDL-P (HDL particles), large HDL-P, and apoC3-lacking HDL-C were significantly associated with lower incidence/progression of AVC. Neither small or medium HDL-P nor apoC3-containing HDL-C was significantly associated with AVC incidence/progression. When included together, a significant association was observed only for HDL-C, but not for HDL-P. Secondary analyses showed an inverse relationship between CETP mass, but not activity, and AVC incidence/progression. In exploratory assessments, inverse associations for HDL-C, HDL-P, large HDL-P, and apoC3-lacking HDL with AVC incidence/progression were more pronounced for older, male, and White participants. ApoC3-containing HDL-C only showed a positive association with AVC in these subgroups.

CONCLUSIONS

In a multiethnic population, HDL-C, HDL-P, large HDL-P, and apoC3-lacking HDL-C were inversely associated with long-term incidence and progression of AVC. Further investigation of HDL composition and mechanisms could be useful in understanding pathways that slow AVC.

High C-Terminal Fibroblast Growth Factor-23, Intact Parathyroid Hormone, and Interleukin-6 as Determinants of Valvular Calcification in Regular Hemodialysis Patients

Purpose

Biggest cause of death in chronic kidney disease-hemodialysis (CKD-HD) patients is cardiovascular disease (CVD). Cardiovascular disease is often associated with mineral bone disorders (MBD), especially vascular and valvular calcification. Biomarkers such as C-terminal-fibroblast growth factor-23 (FGF-23), intact parathyroid hormone (iPTH), and interleukin-6 (IL-6) were investigated. Only few studies have focused on valvular calcification in CKD-HD patients, with controversial results. The present study aimed to investigate whether high C-terminal-FGF-23, iPTH, and IL-6 can be used as determinants of valvular calcification in CKD-MBD patients undergoing regular HD.

Patients and Methods

This was an analytical cross-sectional study which involved CKD-HD patients aged 18–60 years with no history of CVD, malignancy, and diabetes mellitus. C-terminal FGF-23 was measured using enzyme-linked immunosorbent assay (ELISA) kit, iPTH using chemiluminescent immunometric method, and IL-6 using sandwich enzyme immunoassay technique. Valvular calcification on aortic and mitral valves was examined with echocardiography. Data analysis was done using Chi-squared test or Fisher’s exact test as appropriate and multivariate logistic regression analysis.

Results

Bivariate analysis with Fisher’s exact test showed significant association of prevalence ratio (PR) of C-terminal FGF-23 (PR = 1.33; p = 0.003; CI (1.017–1.748)), iPTH (PR = 1.361; p = 0.002; CI (1.02–1.816)), and IL-6 (PR = 1.2; p = 0.019; CI (1.000–1.446)) with valvular calcification. Multivariate analysis with logistic regression showed high C-terminal FGF-23 (exp (B) value of 16.44; p = 0.045; CI (1.07–252.75)), iPTH (exp (B) value of 33.312; p = 0.016; CI (1.94–571.71)), and IL-6 (exp (B) value of 21.58; p = 0.0381; CI (1.18–394.87)) were determinants of valvular calcification in CKD-MBD patients undergoing regular HD.

Conclusion

This study demonstrated that high C-terminal FGF-23, iPTH, and IL-6 were determinants of valvular calcification in CKD-MBD patients undergoing regular HD.

Hyperphosphatemia and Cardiovascular Disease

Hyperphosphatemia or even serum phosphate levels within the “normal laboratory range” are highly associated with increased cardiovascular disease risk and mortality in the general population and patients suffering from chronic kidney disease (CKD). As the kidney function declines, serum phosphate levels rise and subsequently induce the development of hypertension, vascular calcification, cardiac valvular calcification, atherosclerosis, left ventricular hypertrophy and myocardial fibrosis by distinct mechanisms. Therefore, phosphate is considered as a promising therapeutic target to improve the cardiovascular outcome in CKD patients. The current therapeutic strategies are based on dietary and pharmacological reduction of serum phosphate levels to prevent hyperphosphatemia in CKD patients. Large randomized clinical trials with hard endpoints are urgently needed to establish a causal relationship between phosphate excess and cardiovascular disease (CVD) and to determine if lowering serum phosphate constitutes an effective intervention for the prevention and treatment of CVD.

Emerging roles of fibroblasts in cardiovascular calcification

Cardiovascular calcification, a kind of ectopic mineralization in cardiovascular system, including atherosclerotic calcification, arterial medial calcification, valve calcification and the gradually recognized heart muscle calcification, is a complex pathophysiological process correlated with poor prognosis. Although several cell types such as smooth muscle cells have been proven critical in vascular calcification, the aetiology of cardiovascular calcification remains to be clarified due to the diversity of cellular origin. Fibroblasts, which possess remarkable phenotypic plasticity that allows rapid adaption to fluctuating environment cues, have been demonstrated to play important roles in calcification of vasculature, valve and heart though our knowledge of the mechanisms controlling fibroblast phenotypic switching in the calcified process is far from complete. Indeed, the lack of definitive fibroblast lineage‐tracing studies and typical expression markers of fibroblasts raise major concerns regarding the contributions of fibroblasts during all the stages of cardiovascular calcification. The goal of this review was to rigorously summarize the current knowledge regarding possible phenotypes exhibited by fibroblasts within calcified cardiovascular system and evaluate the potential therapeutic targets that may control the phenotypic transition of fibroblasts in cardiovascular calcification.

Clinical Relevance of Plasma Endogenous Tissue-Plasminogen Activator and Aortic Valve Sclerosis: Performance as a Diagnostic Biomarker

Background: Aortic valve sclerosis (AVSc), a common precursor to calcific aortic valve disease, may progress into advanced aortic stenosis with hemodynamic instability. However, plasma biomarkers of such a subclinical condition remain lacking. Since impaired fibrinolysis featuring dysregulated tissue plasminogen activator (t-PA) is involved in several cardiovascular diseases, we investigated whether endogenous t-PA was also associated with AVSc.

Methods: Plasma t-PA levels were measured in 295 consecutive patients undergoing standard echocardiography and Doppler flow imaging. Multiple logistic regression analyses were used to assess the association between t-PA and AVSc. Receiver operating characteristic curve analysis was performed for determining the diagnostic value of t-PA for AVSc. The performance of adding t-PA to clinical signatures of AVSc was evaluated. Concentration of t-PA was assessed in human sclerotic and non-sclerotic aortic valves by histology and immunohistochemistry analysis.

Results: Plasma t-PA was higher in patients with AVSc than in non-AVSc counterparts (median, 2063.10 vs. 1403.17 pg/mL, p < 0.01). C-statistics of plasma t-PA for discriminating AVSc was 0.698 (95%CI: 0.639–0.758). The performance of t-PA for identifying AVSc was better among male and non-hypertensive patients [C-statistics (95%CI): 0.712 (0.634–0.790) and 0.805 (0.693–0.916), respectively]. Combination of t-PA and clinical factors improved classification of the patients (category-free NRI: 0.452, p < 0.001; IDI: 0.020, p = 0.012). The concentration of t-PA was three times higher in sclerotic compared to non-sclerotic aortic valves.

Conclusion: Elevated circulating t-PA level confers an increased risk for AVSc. Further prospective studies with larger sample size are needed to examine if t-PA could serve as a diagnostic clinical marker for AVSc.

Lipid mass spectrometry imaging and proteomic analysis of severe aortic stenosis

Severe aortic stenosis (AS) is prevalent in adults ≥ 65 years, a significant cause of morbidity and mortality, with no medical therapy. Lipid and proteomic alterations of human AS tissue were determined using mass spectrometry imaging (MSI) and liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS) to understand histopathology, potential biomarkers of disease, and progression from non-calcified to calcified phenotype. A reproducible MSI method was developed using healthy murine aortic valves (n = 3) and subsequently applied to human AS (n = 2). Relative lipid levels were spatially mapped and associated with different microdomains. Proteomics for non-calcified and calcified microdomains were performed to ascertain differences in expression. Increased pro-osteogenic and inflammatory lysophosphatidylcholine (LPC) 16:0 and 18:0 were co-localized with calcified microdomains. Proteomics analysis identified differential patterns in calcified microdomains with high LPC and low cholesterol as compared to non-calcified microdomains with low LPC and high cholesterol. Calcified microdomains had higher levels of: apolipoproteins (Apo) B-100 (p < 0.001) and Apo A-IV (p < 0.001), complement C3 and C4-B (p < 0.001), C5 (p = 0.007), C8 beta chain (p = 0.013) and C9 (p = 0.010), antithrombotic proteins alpha-2-macroglobulin (p < 0.0001) and antithrombin III (p = 0.002), and higher anti-calcific fetuin-A (p = 0.02), while the osteoblast differentiating factor transgelin (p < 0.0001), extracellular matrix proteins versican, prolargin, and lumican ( p < 0.001) and regulator protein complement factor H (p < 0.001) were higher in non-calcified microdomains. A combined lipidomic and proteomic approach provided insight into factors potentially contributing to progression from non-calcified to calcific disease in severe AS. Additional studies of these candidates and protein networks could yield new targets for slowing progression of AS.

Calcification of Cardiac Valves in Metabolic Bone Disease: An Updated Review of Clinical Studies

Epidemiological and clinical data have suggested the existence of a relationship between cardiovascular diseases and metabolic bone disease. Several studies have demonstrated that heart valve calcification presents substantial similarities with that of bone. Literature data indicate that there are many active processes which promote osteogenesis and loss of mineralization inhibitors that lead to the deposition of extracellular matrix and proteins of bone tissue in cardiac valves. This review aimed to synthesize the available data in order to allow a better understanding of the relationship between osteoporosis or other metabolic bone diseases, such as primary hyperparathyroidism, and valvular calcification in humans. Electronic databases of Pubmed-Medline, Cochrane Library, and SCOPUS from inception to March 31, 2019 were searched. The full set of the articles potentially eligible were carefully assessed and reviewed. Finally, 23 studies were eligible and included in the systematic review. The majority of studies reported that osteoporosis and/or osteopenia were independent risk factors for valvular calcifications, even after adjusting for common cardiovascular risk factors. This suggests that this relationship is not only due to the presence of common cardiovascular risk factors but rather to underlying biological factors that connect them. Instead, regarding the association between primary hyperparathyroidism and valve calcification, conflicting data were found in the literature. To sum up, most of the literature data confirm that cardiac valve calcification processes are strongly influenced by alterations in bone metabolism. In particular, the patients with osteoporosis or primary hyperparathyroidism have an acceleration in the process of valvular calcification. Additional studies are needed to specifically address the mechanisms by which metabolic bone diseases could influence cardiac valve calcification.

Mitral Annular Calcification: Association with Atherosclerosis and Clinical Implications

PURPOSE OF REVIEW

This review summarizes the pathophysiology of mitral annular calcification (MAC) with recent findings and current strategies for diagnosis and treatment.

RECENT FINDINGS

Major factors in MAC development seem to be shear stress of the flow past the mitral valve, local inflammation, and dysregulation in regulators of mineral metabolism. MAC itself poses daunting technical challenges. Implanting a valve on top of the calcium bar might lead to paravalvular leak (PVL) that is less likely to heal. Annular decalcification allows for better valve seating and potentially better healing and less PVL. This, however, comes with the risk for catastrophic atrioventricular groove disruption. MAC can be sharply dissected with the scalpel; the annulus can be reconstructed with the autologous pericardium. Transcatheter mitral valve replacement is a promising approach in the treatment of patients who are deemed high-risk surgical candidates with severe MAC. MAC is a multifactorial disease that has some commonalities with atherosclerosis, mainly regarding lipid accumulation and calcium deposition. It is of great clinical importance, being a risk marker of cardiovascular events (including sudden death) and, with its progression, can have a negative impact on patients' lives.

Disease Activity in Mitral Annular Calcification

BACKGROUND

Mitral annular calcification (MAC) is associated with cardiovascular events and mitral valve dysfunction. However, the underlying pathophysiology remains incompletely understood. In this prospective longitudinal study, we used a multimodality approach including positron emission tomography, computed tomography, and echocardiography to investigate the pathophysiology of MAC and assess factors associated with disease activity and progression.

METHODS

A total of 104 patients (age 72±8 years, 30% women) with calcific aortic valve disease, therefore predisposed to MAC, underwent ¹⁸F-sodium fluoride (calcification activity) and ¹⁸F-Fluorodeoxyglucose (inflammation activity) positron emission tomography, computed tomography calcium scoring, and echocardiography. Sixty patients underwent repeat computed tomography and echocardiography after 2 years.

RESULTS

MAC (mitral annular calcium score >0) was present in 35 (33.7%) patients who had increased ¹⁸F-fluoride (tissue-to-background ratio, 2.32 [95% CI, 1.81-3.27] versus 1.30 [1.22-1.49]; P<0.001) and ¹⁸F-Fluorodeoxyglucose activity (tissue-to-background ratio, 1.44 [1.37-1.58] versus 1.17 [1.12-1.24]; P<0.001) compared with patients without MAC. MAC activity (¹⁸F-fluoride uptake) was closely associated with the local calcium score and ¹⁸F-Fluorodeoxyglucose uptake, as well as female sex and renal function. Similarly, MAC progression was closely associated with local factors, in particular, baseline MAC. Traditional cardiovascular risk factors and calcification activity in bone or remote atherosclerotic areas were not associated with disease activity nor progression.

CONCLUSIONS

MAC is characterized by increased local calcification activity and inflammation. Baseline MAC burden was associated with disease activity and the rate of subsequent progression. This suggests a self-perpetuating cycle of calcification and inflammation that may be the target of future therapeutic interventions.

Biomarkers of mineral metabolism and progression of aortic valve and mitral annular calcification: The Multi-Ethnic Study of Atherosclerosis

BACKGROUND AND AIMS

Previous research has implicated dysregulation of phosphate metabolism and calcium-phosphate solubilization in cardiovascular calcification, but epidemiologic studies evaluating longitudinal associations with valvular or annular calcification by computed tomography (CT), a highly sensitive imaging modality, are lacking. Our primary aim was to investigate the associations of mineral biomarkers with incidence and progression of aortic valve calcification (AVC) and mitral annular calcification (MAC).

METHODS

We evaluated the associations of serum FGF-23 (n = 6547 participants), phosphate (n = 6547), and fetuin-A (n = 2550) measured at baseline in the community-based Multi-Ethnic Study of Atherosclerosis with AVC and MAC on CT performed at baseline and at a median of 2.4 (1.6, 3.1) years later. We used linear mixed-effects models to account simultaneously for prevalence, incidence and progression of AVC and MAC.

RESULTS

After adjustment for demographic and clinical characteristics, a significant association was documented for FGF-23 with accelerated annual progression of MAC (2.83 Agatston units (AU), 95% CI = 0.49, 5.17 AU, per standard deviation (18.46 pg/mL) of FGF-23), but this was not seen for phosphate or fetuin-A. None of these biomarkers was associated with accelerated annual progression of AVC.

CONCLUSIONS

This study provides evidence relating serum FGF-23 to accelerated annual MAC progression. Whether this mineral regulator is a risk marker or is involved in pathogenesis merits further investigation.

The novel inflammatory marker GlycA and the prevalence and progression of valvular and thoracic aortic calcification: The Multi-Ethnic Study of Atherosclerosis

BACKGROUND AND AIMS

GlycA is a novel composite biomarker of systemic inflammation reflecting posttranslational glycosylation of acute phase reactants. GlycA has been associated with coronary artery calcium, cardiovascular disease (CVD) events and mortality. Vascular calcifications outside of the coronary arteries are risk markers of CVD and mortality. Whether GlycA is linked to extra-coronary calcifications (ECC) is not well established.

METHODS

We studied 6462 MESA participants free of clinical CVD who had plasma GlycA measured at baseline. ECCs [calcification in aortic valve (AVC), mitral annulus (MAC), ascending and descending thoracic aorta (ATAC, DTAC)] were ascertained at baseline and follow-up visit (median 2.3-yrs later) by cardiac CT. Poisson regression models with robust variance estimation assessed associations of GlycA with prevalent and incident ECC. Linear mixed models assessed the cross-sectional and 2-year change in ECC. Models were adjusted for demographic and lifestyle factors.

RESULTS

In cross-sectional analysis, GlycA (per SD increment) was positively associated with prevalent AVC, ATAC and DTAC with adjusted prevalence ratios (95% CI) of 1.08 (1.01-1.14), 1.18 (1.03-1.34) and 1.10 (1.06-1.14), respectively. There was also a significant association between GlycA and baseline extent of both ATAC and DTAC. Longitudinally, GlycA was positively associated with incident MAC and DTAC, with adjusted incidence ratios of 1.18 (1.03-1.37) and 1.17 (1.07-1.28), respectively. GlycA was also associated with 2-year change in MAC and DTAC extent.

CONCLUSIONS

In this diverse cohort free from clinical CVD, we found GlycA was positively associated with prevalent and incident ECC measures, in particular for progression of MAC and DTAC.

Exposure to ambient air pollution and calcification of the mitral annulus and aortic valve: the multi-ethnic study of atherosclerosis (MESA)

BACKGROUND

Long-term exposure to high ambient air pollution has been associated with coronary artery calcium (CAC), a marker of cardiovascular disease (CVD). Calcifications of left-sided heart valves are also markers of CVD risk. We investigated whether air pollution was associated with valvular calcification and its progression.

METHODS

We studied 6253 MESA participants aged 45-84 years who underwent two cardiac CT scans 2.5 years apart to quantify aortic valve calcium (AVC) and mitral annular calcium (MAC). CAC was included for the same timeframe for comparison with AVC/MAC. Ambient particulate matter <2.5 μm (PM_2.5) and oxides of nitrogen (NO_x) concentrations were predicted from residence-specific spatio-temporal models.

RESULTS

The mean age (SD) of the study sample was 62 (10) years, 39% were white, 27% black, 22% Hispanic, and 12% Chinese. The prevalence of AVC and MAC at baseline were 13% and 9% respectively, compared to 50% prevalence of CAC. The adjusted prevalence ratios of AVC and MAC for each 5 μg/m³ higher PM_2.5 was 1.19 (95% CI 0.87, 1.62) and 1.20 (0.81, 1.77) respectively, and for CAC was 1.14 (1.01, 1.27). Over 2.5 years, the mean change in Agatston units/year for each 5 μg/m³ higher PM_2.5 concentration was 0.29 (-5.05, 5.63) for AVC and 4.38 (-9.13, 17.88) for MAC, compared to 8.66 (0.61, 16.71) for CAC. We found no significant associations of NOx with AVC and MAC.

CONCLUSION

Our findings suggest a trend towards increased 2.5-year progression of MAC with exposure to outdoor PM_2.5, although this association could not be confirmed. Additional well-powered studies with longer periods of follow-up are needed to further study associations of air pollution with valvular calcium.

TRIAL REGISTRATION

Although MESA is not a clinical trial, this cohort is registered at ClinicalTrials.gov Identifier: NCT00005487; Date of registration May 25, 2000.

Relationship of bone mineral density with valvular and annular calcification in community-dwelling older people: The Cardiovascular Health Study

Associations between bone mineral density and aortic valvular, aortic annular, and mitral annular calcification were investigated in a cross-sectional analysis of a population-based cohort of 1497 older adults. Although there was no association between continuous bone mineral density and outcomes, a significant association between osteoporosis and aortic valvular calcification in men was found.

INTRODUCTION

The process of cardiac calcification bears a resemblance to skeletal bone metabolism and its regulation. Experimental studies suggest that bone mineral density (BMD) and valvular calcification may be reciprocally related, but epidemiologic data are sparse.

METHODS

We tested the hypothesis that BMD of the total hip and femoral neck measured by dual-energy X-ray absorptiometry (DXA) is inversely associated with prevalence of three echocardiographic measures of cardiac calcification in a cross-sectional analysis of 1497 older adults from the Cardiovascular Health Study. The adjusted association of BMD with aortic valve calcification (AVC), aortic annular calcification (AAC), and mitral annular calcification (MAC) was assessed with relative risk (RR) regression.

RESULTS

Mean (SD) age was 76.2 (4.8) years; 58% were women. Cardiac calcification was highly prevalent in women and men: AVC, 59.5 and 71.0%; AAC 45.1 and 46.7%; MAC 42.8 and 39.5%, respectively. After limited and full adjustment for potential confounders, no statistically significant associations were detected between continuous BMD at either site and the three measures of calcification. Assessment of WHO BMD categories revealed a significant association between osteoporosis at the total hip and AVC in men (adjusted RR compared with normal BMD = 1.24 (1.01-1.53)). In graded sensitivity analyses, there were apparent inverse associations between femoral neck BMD and AVC with stenosis in men, and femoral neck BMD and moderate/severe MAC in women, but these were not significant.

CONCLUSION

These findings support further investigation of the sex-specific relationships between low BMD and cardiac calcification, and whether processes linking the two could be targeted for therapeutic ends.

Relation of Serum Vitamin D to Risk of Mitral Annular and Aortic Valve Calcium (from the Multi-Ethnic Study of Atherosclerosis)

Serum 25-hydroxyvitamin D [25(OH)D] concentration has been identified as a possible modifiable risk factor for cardiovascular disease (CVD). We hypothesized that serum 25(OH)D concentration would be associated with calcifications of the left-sided heart valves, which are markers of CVD risk. Aortic valve calcium (AVC) and mitral annular calcium (MAC) were quantified from cardiac computed tomography scans performed on 5,530 Multi-Ethnic Study of Atherosclerosis participants at the baseline examination (2000 to 2002) and at a follow-up visit at either Examination 2 (2002 to 2004) or Examination 3 (2004 to 2005). 25(OH)D was measured from serum samples collected at the baseline examination. Using relative risk regression, we evaluated the multivariable-adjusted risk of prevalent and incident AVC and MAC in this ethnically diverse population free of clinical CVD at baseline. The mean age of participants was 62 ± 10 years; 53% were women, 40% white, 26% black, 21% Hispanic, and 12% Chinese. Prevalent AVC and MAC were observed in 12% and 9% of study sample, respectively. There were no significant associations between 25(OH)D and prevalent AVC or MAC. Over a mean follow-up of 2.5 years, 4% developed incident AVC and 5% developed incident MAC. After adjusting for demographic variables, each 10 ng/ml higher serum 25(OH)D was associated with a 15% (relative risk 0.85, 95% confidence interval 0.74 to 0.98) lower risk of incident MAC but not AVC. However, this association was no longer significant after adjusting for lifestyle and CVD risk factors. Results suggest a possible link between serum 25(OH)D and the risk for incident MAC, but future studies with longer follow-up are needed to further test this association.

Extrarenal effects of FGF23

Chronic kidney disease (CKD) is associated with an increased risk of cardiovascular mortality, infections, and impaired cognitive function. It is characterized by excessively increased levels of the phosphaturic hormone fibroblast growth factor 23 (FGF23) and a deficiency of its co-receptor Klotho. Despite the important physiological effect of FGF23 in maintaining phosphate homeostasis, there is increasing evidence that higher FGF23 levels are a risk factor for mortality and cardiovascular disease. FGF23 directly induces left ventricular hypertrophy via activation of the FGF receptor 4/calcineurin/nuclear factor of activated T cells signaling pathway. By contrast, the impact of FGF23 on endothelial function and the development of atherosclerosis are poorly understood. The results of recent experimental studies indicate that FGF23 directly impacts on hippocampal neurons and may thereby impair learning and memory function in CKD patients. Finally, it has been shown that FGF23 interferes with the immune system by directly acting on polymorphonuclear leukocytes and macrophages. In this review, we discuss recent data from clinical and experimental studies on the extrarenal effects of FGF23 with respect to the cardiovascular, central nervous, and immune systems.

Specifics of fetuin-A levels in distinct types of chronic heart failure

INTRODUCTION

Fetuin-A has been described to correlate inversely with vascular calcification both in animal models but also in patients with heart and renal disease. In this current study, we sought to investigate whether fetuin-A might be a useful marker for the discrimination of ischemic (ICM) from dilated cardiomyopathy (DCM).

METHODS

A total of 124 non-consecutive patients were included in this study, 59 patients suffered from ICM and 65 patients from DCM. Serum samples were obtained during out-patient visits and analyzed for fetuin-A by ELISA.

RESULTS

Median fetuin-A concentration in the overall cohort was significantly lower in ICM patients compared to DCM patients (62.2±16.4 μg/mL vs. 129.6±56.6 μg/mL; P<.001). A positive correlation of fetuin-A levels was found with BMI, cholesterol, LDL/HDL ratio and triglycerides and an inverse correlation with age (r=-.36; P<.001). Moreover, patients suffering from (stable) angina pectoris evidenced lower fetuin-A levels compared to non-symptomatic patients (73.1±22.7 μg/mL vs. 83.7±26.2 μg/mL; P=.047) CONCLUSIONS: Fetuin-A was shown to be a potential discriminator and biomarker for the differential diagnosis between ICM and DCM. Fetuin-A levels might also be helpful in the process of diagnostic decision-making in regards to invasive management or medical therapy.

Aortic calcification burden predicts deterioration of renal function after radical nephrectomy

Background

Radical nephrectomy for renal cell carcinoma (RCC) is a risk factor for the development of chronic kidney disease (CKD), and the possibility of postoperative deterioration of renal function must be considered before surgery. We investigated the contribution of the aortic calcification index (ACI) to the prediction of deterioration of renal function in patients undergoing radical nephrectomy.

Methods

Between January 1995 and December 2012, we performed 511 consecutive radical nephrectomies for patients with RCC. We retrospectively studied data from 109 patients who had regular postoperative follow-up of renal function for at least five years. The patients were divided into non-CKD and pre-CKD based on a preoperative estimated glomerular filtration rate (eGFR) of ≥60 mL/min/1.73 m² or <60 mL/min/1.73 m², respectively. The ACI was quantitatively measured by abdominal computed tomography before surgery. The patients in each group were stratified between low and high ACIs. Variables such as age, sex, comorbidities, and pre- and postoperative renal function were compared between patients with a low or high ACI in each group. Renal function deterioration-free interval rates were evaluated by Kaplan-Meier analysis. Factors independently associated with deterioration of renal function were determined using multivariate analysis.

Results

The median age, preoperative eGFR, and ACI in this cohort were 65 years, 68 mL/min/1.73 m², and 8.3%, respectively. Higher ACI (≥8.3%) was significantly associated with eGFR decline in both non-CKD and pre-CKD groups. Renal function deterioration-free interval rates were significantly lower in the ACI-high than ACI-low strata in both of the non-CKD and pre-CKD groups. Multivariate analysis showed that higher ACI was an independent risk factor for deterioration of renal function at 5 years after radical nephrectomy.

Conclusions

Aortic calcification burden is a potential predictor of deterioration of renal function after radical nephrectomy.

Trial registration

This study was registered as a clinical trial: UMIN000023577

Electronic supplementary material

The online version of this article (doi:10.1186/s12894-017-0202-x) contains supplementary material, which is available to authorized users.