Histopathological assessment of calcification and inflammation of calcific aortic valves from patients with and without diabetes mellitus

A high-volume study on the impact of diabetes mellitus on clinical outcomes after surgical and percutaneous cardiac interventions

BACKGROUND

Type I and type II diabetes mellitus (DM) patients have a higher prevalence of cardiovascular diseases, as well as a higher mortality risk of cardiovascular diseases and interventions. This study provides an update on the impact of DM on clinical outcomes, including mortality, complications and reinterventions, using data on percutaneous and surgical cardiac interventions in the Netherlands.

METHODS

This is a retrospective, nearby nationwide study using real-world observational data registered by the Netherlands Heart Registration (NHR) between 2015 and 2020. Patients treated for combined or isolated coronary artery disease (CAD) and aortic valve disease (AVD) were studied. Bivariate analyses and multivariate logistic regression models were used to evaluate the association between DM and clinical outcomes both unadjusted and adjusted for baseline characteristics.

RESULTS

241,360 patients underwent the following interventions; percutaneous coronary intervention(N = 177,556), coronary artery bypass grafting(N = 39,069), transcatheter aortic valve implantation(N = 11,819), aortic valve replacement(N = 8,028) and combined CABG and AVR(N = 4,888). The incidence of DM type I and II was 21.1%, 26.7%, 17.8%, 27.6% and 27% respectively. For all procedures, there are statistically significant differences between patients living with and without diabetes, adjusted for baseline characteristics, at the expense of patients with diabetes for 30-days mortality after PCI (OR = 1.68; p <.001); 120-days mortality after CABG (OR = 1.35; p <.001), AVR (OR = 1.5; p <.03) and CABG + AVR (OR = 1.42; p =.02); and 1-year mortality after CABG (OR = 1.43; p <.001), TAVI (OR = 1.21; p =.01) and PCI (OR = 1.68; p <.001).

CONCLUSION

Patients with DM remain to have unfavourable outcomes compared to nondiabetic patients which calls for a critical reappraisal of existing care pathways aimed at diabetic patients within the cardiovascular field.

Influence of diabetes mellitus on the pathological profile of aortic stenosis: a sex-based approach

BACKGROUND

Diabetes mellitus (DM) accelerates the progression of aortic stenosis (AS), but how their underlying molecular mechanisms interact is not clear. Moreover, whether DM contributes to clinically relevant sex-differences in AS is unknown. In this work we aim to characterize the sex-specific profile of major pathological mechanisms fundamental to aortic valve (AV) degeneration in AS patients with or without concomitant DM.

METHODS

283 patients with severe AS undergoing surgical valve replacement (27.6% DM, 59.4% men) were recruited. Expression of pathological markers related to AS were thoroughly assessed in AVs and valve interstitial cells (VICs) according to sex and presence of DM. Complementary in vitro experiments in VICs in the presence of high-glucose levels (25 mM) for 24, 48 and 72 h were performed.

RESULTS

Oxidative stress and metabolic dysfunction markers were increased in AVs from diabetic AS patients compared to non-diabetic patients in both sexes. However, disbalanced oxidative stress and enhanced inflammation were more predominant in AVs from male AS diabetic patients. Osteogenic markers were exclusively increased in the AVs of diabetic women. Basal characterization of VICs confirmed that oxidative stress, inflammation, calcification, and metabolic alteration profiles were increased in diabetic VICs with sex-specific differences. VICs cultured in hyperglycemic-like conditions triggered inflammatory responses in men, whereas in women rapid and higher production of pro-osteogenic molecules.

CONCLUSIONS

DM produces sex-specific pathological phenotypes in AV of AS patients. Importantly, women with diabetes are more prone to develop AV calcification. DM should be considered as a risk factor in AS especially in women.

Shared gene characteristics and molecular mechanisms of macrophages M1 polarization in calcified aortic valve disease

Background

CAVD is a common cardiovascular disease, but currently there is no drug treatment. Therefore, it is urgent to find new and effective drug therapeutic targets. Recent evidence has shown that the infiltration of M1 macrophages increased in the calcified aortic valve tissues, but the mechanism has not been fully elucidated. The purpose of this study was to explore the shared gene characteristics and molecular mechanisms of macrophages M1 polarization in CAVD, in order to provide a theoretical basis for new drugs of CAVD.

Methods

The mRNA datasets of CAVD and M1 polarization were downloaded from Gene Expression Omnibus (GEO) database. R language, String, and Cytoscape were used to analyze the functions and pathways of DEGs and feature genes. Immunohistochemical staining and Western Blot were performed to verify the selected hub genes.

Results

CCR7 and GZMB were two genes appeared together in hub genes of M1-polarized and CAVD datasets that might be involved in the process of CAVD and macrophages M1 polarization. CCR7 and CD86 were significantly increased, while CD163 was significantly decreased in the calcified aortic valve tissues. The infiltration of M1 macrophages was increased, on the contrary, the infiltration of M2 macrophages was decreased in the calcified aortic valve tissues.

Conclusion

This study reveals the shared gene characteristics and molecular mechanisms of CAVD and macrophages M1 polarization. The hub genes and pathways we found may provide new ideas for the mechanisms underlying the occurrence of M1 polarization during CAVD process.

Interactive contribution of hyperinsulinemia, hyperglycemia, and mammalian target of rapamycin signaling to valvular interstitial cell differentiation and matrix remodeling

Diabetes and its major key determinants insulin resistance and hyperglycemia are known risk factors for calcific aortic valve disease (CAVD). The processes leading to molecular and structural alterations of the aortic valve are yet not fully understood. In previous studies, we could show that valvular interstitial cells (VIC) display canonical elements of classical insulin signaling and develop insulin resistance upon hyperinsulinemia and hyperglycemia accompanied by impaired glucose metabolism. Analyses of cultured VIC and aortic valve tissue revealed extracellular matrix remodeling and degenerative processes. Since PI3K signaling through mammalian target of rapamycin (mTOR) is involved in fibrotic processes of the heart, we aim at further functional investigation of this particular Akt-downstream signaling pathway in the context of diabetes-induced CAVD. Primary cultures of VIC were treated with hyperinsulinemia and hyperglycemia. Phosphorylation of mTOR(Ser²⁴⁴⁸) was determined by Western blot analysis after acute insulin stimulus. Inhibition of mTOR phosphorylation was performed by rapamycin. Phosphorylation of mTOR complex 1 (MTORC1) downstream substrates 4E-BP1(Thr^37/46) and P70S6K(Thr³⁸⁹), and MTORC2 downstream substrate Akt(Ser⁴⁷³) as well as the PDK1-dependent phosphorylation of Akt(Thr³⁰⁸) was investigated. Markers for extracellular matrix remodeling, cell differentiation and degenerative changes were analyzed by Western blot analysis, semi-quantitative real-time PCR and colorimetric assays. Hyperinsulinemia and hyperglycemia lead to alterations of VIC activation, differentiation and matrix remodeling as well as to an abrogation of mTOR phosphorylation. Inhibition of mTOR signaling by rapamycin leads to a general downregulation of matrix molecules, but to an upregulation of α-smooth muscle actin expression and alkaline phosphatase activity. Comparison of expression patterns upon diabetic conditions and rapamycin treatment reveal a possible regulation of particular matrix components and key degeneration markers by MTORC1 downstream signaling. The present findings broaden the understanding of mitogenic signaling pathways in VIC triggered by hyperinsulinemia and hyperglycemia, supporting the quest for developing strategies of prevention and tailored treatment of CAVD in diabetic patients.

Integrated proteomic and metabolomic profile analyses of cardiac valves revealed molecular mechanisms and targets in calcific aortic valve disease

Background

This study aimed to define changes in the metabolic and protein profiles of patients with calcific aortic valve disease (CAVD).

Methods and results

We analyzed cardiac valve samples of patients with and without (control) CAVD (n = 24 per group) using untargeted metabolomics and tandem mass tag-based quantitative proteomics. Significantly different metabolites and proteins between the CAVD and control groups were screened; then, functional enrichment was analyzed. We analyzed co-expressed differential metabolites and proteins, and constructed a metabolite-protein-pathway network. The expression of key proteins was validated using western blotting. Differential analysis identified 229 metabolites in CAVD among which, 2-aminophenol, hydroxykynurenine, erythritol, carnosine, and choline were the top five. Proteomic analysis identified 549 differentially expressed proteins in CAVD, most of which were localized in the nuclear, cytoplasmic, extracellular, and plasma membranes. Levels of selenium binding protein 1 (SELENBP1) positively correlated with multiple metabolites. Adenosine triphosphate-binding cassette transporters, starch and sucrose metabolism, hypoxia-inducible factor 1 (HIF-1) signaling, and purine metabolism were key pathways in the network. Ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1), calcium²⁺/calmodulin-dependent protein kinase II delta (CAMK2D), and ATP binding cassette subfamily a member 8 (ABCA8) were identified as hub proteins in the metabolite-protein-pathway network as they interacted with ADP, glucose 6-phosphate, choline, and other proteins. Western blotting confirmed that ENPP1 was upregulated, whereas ABCA8 and CAMK2D were downregulated in CAVD samples.

Conclusion

The metabolic and protein profiles of cardiac valves from patients with CAVD significantly changed. The present findings provide a holistic view of the molecular mechanisms underlying CAVD that may lead to the development of novel diagnostic biomarkers and therapeutic targets to treat CAVD.

Role of endothelial CXCR4 in the development of aortic valve stenosis

Background

CXCL12/CXCR4 signaling is essential in cardiac development and repair, however, its contribution to aortic valve stenosis (AVS) remains unclear. In this study, we tested the role of endothelial CXCR4 on the development of AVS.

Materials and methods

We generated CXCR4 endothelial cell-specific knockout mice (EC CXCR4 KO) by crossing CXCR4^fl/fl mice with Tie2-Cre mice to study the role of endothelial cell CXCR4 in AVS. CXCR4^fl/fl mice were used as controls. Echocardiography was used to assess the aortic valve and cardiac function. Heart samples containing the aortic valve were stained using Alizarin Red for detection of calcification. Masson’s trichrome staining was used for the detection of fibrosis. The apex of the heart samples was stained with wheat germ agglutinin (WGA) to visualize ventricular hypertrophy.

Results

Compared with the control group, the deletion of CXCR4 in endothelial cells led to significantly increased aortic valve peak velocity and aortic valve peak pressure gradient, with decreased aortic valve area and ejection fraction. EC CXCR4 KO mice also developed cardiac hypertrophy as evidenced by increased diastolic and systolic left ventricle posterior wall thickness (LVPW), cardiac myocyte size, and heart weight (HW) to body weight (BW) ratio. Our data also confirmed increased microcalcifications, interstitial fibrosis, and thickened valvular leaflets of the EC CXCR4 KO mice.

Conclusion

The data collected throughout this study suggest the deletion of CXCR4 in endothelial cells is linked to the development of aortic valve stenosis and left ventricular hypertrophy. The statistically significant parameters measured indicate that endothelial cell CXCR4 plays an important role in aortic valve development and function. We have compiled compelling evidence that EC CXCR4 KO mice can be used as a novel model for AVS.

Clinical characteristics of severe aortic stenosis patients combined with diabetes mellitus after transcatheter aortic valve replacement and short-term outcome

OBJECTIVES

Type 2 diabetes (T2DM) is a common comorbidity in patients with degenerative aortic stenosis (AS).As a key item of the American Society of Thoracic Surgeons (STS) score, it has a vital impact on the clinical prognosis of traditional thoracic surgery. T2DM has an adverse effect on the morbidity and mortality of cardiovascular diseases. At the same time, studies have shown that T2DM are associated with myocardial hypertrophy and remodeling, decreased left ventricular function, and worsening heart failure symptoms in the AS patients. Transcatheter aortic valve replacement (TAVR) as an interventional method to replace the aortic valve has better safety for middle and high risk patients in surgery, but the impact of T2DM on the clinical outcome of TAVR in AS patients is not clear.By analyzing the clinical and image characteristics of patients with AS and T2DM who received TAVR treatment, so as to explore the effect of T2DM on the perioperative complications and prognosis of TAVR.

METHODS

A total of 100 consecutive patients with severe AS, who underwent TAVR treatment and were followed up for more than 1 month, were selectedin the Second Xiangya Hospital of Central South University from January 2016 to December 2020.Among them, 5 patients who were treated with TAVR due to simple severe aortic regurgitation were not included, therefore a total of 95 patients with severe aortic stenosis were enrolled in this study.The age of the patients was (72.7±4.8) years old, and there were 58 males (61.1%), and the patients with moderate or above aortic regurgitation had 30 cases (31.6%). The patients were divided into a diabetic group and a non-diabetic group according to whether they were combined with T2DM.There was no statistical difference in age, gender, body mass index (BMI), STS score, and New York Heart Association (NYHA) cardiac function classification between the 2 groups (all P>0.05). The primary end point was defined as a composite event consisting of all-cause death and stroke one month after surgery, and the secondary end point was defined as TAVR-related complications immediately after surgery and one month after surgery.The preoperative clinical data, cardiac ultrasound data, CT data, postoperative medication and the incidence of each endpoint event were compared between the 2 groups.The predictive model of adverse events was constructed by single factor and multivariate logistic regression.

RESULTS

Compared with the non-diabetic group, the diabetic group had high blood pressure and chronic renal insufficiency.There was no significant difference in preoperative ultrasound echocardiography between the 2 groups. Preoperative CT evaluation found that the anatomical structure of the aortic root in the diabetic group was smaller than that in the non-diabetic group, and there was no significant difference in the incidence of bicuspid aortic valve between the 2 groups (all P<0.05). In terms of postoperative medication, the use of statins in the diabetes group was significantly higher than that in the non-diabetic group. In the diabetes group, 6 patients (37.5%) received insulin therapy, and 9 patients (56.3%) received oral medication alone.Univariate logistic regression analysis showed that the all-cause death and stroke compound events was increased in the diabetes group in 30 days after TAVR (OR=6.86; 95% CI: 2.14 to 21.79; P<0.01). Heart disease (OR=2.80; 95% CI: 0.99 to 7.88; P<0.05) and chronic renal insufficiency (OR=3.75; 95% CI: 1.24 to 11.34; P<0.05) were also risk factors for all-cause death and stroke compound events.In a multivariate analysis, after adjusting for age, gender, BMI, comorbidities, N-terminal pro-B type natriuretic peptide (NT-proBNP), total calcification score, ejection fraction, and degree of aortic regurgitation, T2DM was still a risk factor for all-cause death and stroke compound events in 30 days after TAVR (OR=12.68; 95% CI: 1.76 to 91.41; P<0.05).

CONCLUSIONS

T2DM is a risk factor for short-term poor prognosis in patients with symptomatic severe AS after TAVR treatment. T2DM should play an important role in the future construction of the TAVR surgical risk assessment system, but the conclusions still need to be further verified by long-term follow-up of large-scale clinical studies.

Aortic valve disease in diabetes: Molecular mechanisms and novel therapies

Valve disease and particularly calcific aortic valve disease (CAVD) and diabetes (DM) are progressive diseases constituting a global health burden for all aging societies (Progress in Cardiovascular Diseases. 2014;56(6):565: Circulation Research. 2021;128(9):1344). Compared to non‐diabetic individuals (The Lancet. 2008;371(9626):1800: The American Journal of Cardiology. 1983;51(3):403: Journal of the American College of Cardiology. 2017;69(12):1523), the diabetic patients have a significantly greater propensity for cardiovascular disorders and faster degeneration of implanted bioprosthetic aortic valves. Previously, using an original experimental model, the diabetic‐hyperlipemic hamsters, we have shown that the earliest alterations induced by these conditions occur at the level of the aortic valves and, with time these changes lead to calcifications and CAVD. However, there are no pharmacological treatments available to reverse or retard the progression of aortic valve disease in diabetes, despite the significant advances in the field. Therefore, it is critical to uncover the mechanisms of valve disease progression, find biomarkers for diagnosis and new targets for therapies. This review aims at presenting an update on the basic research in CAVD in the context of diabetes. We provide an insight into the accumulated data including our results on diabetes‐induced progressive cell and molecular alterations in the aortic valve, new potential biomarkers to assess the evolution and therapy of the disease, advancement in targeted nanotherapies, tissue engineering and the potential use of circulating endothelial progenitor cells in CAVD.

Effects of Altering Mitochondrial Antioxidant Capacity on Molecular and Phenotypic Drivers of Fibrocalcific Aortic Valve Stenosis

Background: While a small number of studies suggest that oxidative stress has an influential role in fibrocalcific aortic valve disease (FCAVD), the roles of specific antioxidant enzymes in progression of this disease remain poorly understood. Here, we focused on selectively altering mitochondrial-derived oxidative stress—which has been shown to alter progression of a myriad of age-associated diseases—on the progression of molecular and phenotypic drivers of FCAVD.

Methods: We generated low-density lipoprotein receptor-deficient, Apolipoprotein B100-only mice (LA) that were either haploinsufficient for MnSOD (LA-MnSOD^+/−) or genetically overexpressing MnSOD (LA-MnSOD^Tg/0). After 6 months of Western diet feeding, mice underwent echocardiography to assess valvular and cardiac function and tissues were harvested. Quantitative-RT PCR, immunohistochemistry, and histopathology were used to measure changes in molecular pathways related to oxidative stress, calcification, and fibrosis.

Results: While reductions in MnSOD increased oxidative stress, there was not an overt phenotypic effect of MnSOD deficiency on valvular and cardiac function in LA-MnSOD^+/− mice. While markers of canonical bone morphogenetic protein signaling tended to increase in valve tissue from LA-MnSOD^+/− (e.g., p-SMAD1/5/8 and osterix), we did not observe statistically significant increases in osteogenic signaling. We did, however, observe highly significant reductions in expression of osteopontin, which were associated with significant increases in calcium burden in LA-MnSOD^+/− mice. Reciprocally, genetically increasing MnSOD did not preserve valve function in LA-MnSOD^Tg/0, but we did observe slight reductions in p-SMAD1/5/8 levels compared to their non-transgenic littermates. Interestingly, overexpression of MnSOD dramatically increased expression of osteopontin in valve tissue from LA-MnSOD^Tg/0 mice, but was not sufficient to attenuate calcium burden when compared to their LA-MnSOD^0/0 littermates.

Conclusions: Collectively, this study demonstrates that maintenance of mitochondrial antioxidant capacity is important in preventing accelerated disease progression in a mouse model of FCAVD, but that effectively altering mitochondrial antioxidant capacity as a monotherapeutic approach to slow key histopathological and molecular drivers of FCAVD remains biologically and therapeutically challenging.

Diabetes Mellitus and Its Implications in Aortic Stenosis Patients

Aortic stenosis (AS) and diabetes mellitus (DM) are both progressive diseases that if left untreated, result in significant morbidity and mortality. Several studies revealed that the prevalence of DM is substantially higher in patients with AS and, thus, the progression from mild to severe AS is greater in those patients with DM. DM and common comorbidities associated with both diseases, DM and AS, increase patient management complexity and make aortic valve replacement the only effective treatment. For that reason, a better understanding of the pathogenesis underlying both these diseases and the relationships between them is necessary to design more appropriate preventive and therapeutic approaches. In this review, we provided an overview of the main aspects of the relationship between AS and DM, including common comorbidities and risk factors. We also discuss the established treatments/therapies in patients with AS and DM.

Calcific Aortic Valve Disease-Natural History and Future Therapeutic Strategies

Calcific aortic valve disease (CAVD) is the most frequent heart valve disorder. It is characterized by an active remodeling process accompanied with valve mineralization, that results in a progressive aortic valve narrowing, significant restriction of the valvular area, and impairment of blood flow.The pathophysiology of CAVD is a multifaceted process, involving genetic factors, chronic inflammation, lipid deposition, and valve mineralization. Mineralization is strictly related to the inflammatory process in which both, innate, and adaptive immunity are involved. The underlying pathophysiological pathways that go from inflammation to calcification and, finally lead to severe stenosis, remain, however, incompletely understood. Histopathological studies are limited to patients with severe CAVD and no samples are available for longitudinal studies of disease progression. Therefore, alternative routes should be explored to investigate the pathogenesis and progression of CAVD.Recently, increasing evidence suggests that epigenetic markers such as non-coding RNAs are implicated in the landscape of phenotypical changes occurring in CAVD. Furthermore, the microbiome, an essential player in several diseases, including the cardiovascular ones, has recently been linked to the inflammation process occurring in CAVD. In the present review, we analyze and discuss the CAVD pathophysiology and future therapeutic strategies, focusing on the real and putative role of inflammation, calcification, and microbiome.

Adaptive immune cells in calcific aortic valve disease

Calcific aortic valve disease (CAVD) is highly prevalent and has no pharmaceutical treatment. Surgical replacement of the aortic valve has proved effective in advanced disease but is costly, time limited, and in many cases not optimal for elderly patients. This has driven an increasing interest in noninvasive therapies for patients with CAVD. Adaptive immune cell signaling in the aortic valve has shown potential as a target for such a therapy. Up to 15% of cells in the healthy aortic valve are hematopoietic in origin, and these cells, which include macrophages, T lymphocytes, and B lymphocytes, are increased further in calcified specimens. Additionally, cytokine signaling has been shown to play a causative role in aortic valve calcification both in vitro and in vivo. This review summarizes the physiological presence of hematopoietic cells in the valve, innate and adaptive immune cell infiltration in disease states, and the cytokine signaling pathways that play a significant role in CAVD pathophysiology and may prove to be pharmaceutical targets for this disease in the near future.

Standardization of Human Calcific Aortic Valve Disease in vitro Modeling Reveals Passage-Dependent Calcification

Aortic valvular interstitial cells (VICs) isolated from patients undergoing valve replacement are commonly used as in vitro models of calcific aortic valve disease (CAVD). Standardization of VIC calcification, however, has not been implemented, which impairs comparison of results from different studies. We hypothesized that different culture methods impact the calcification phenotype of human VICs. We sought to identify the key parameters impacting calcification in primary human VICs to standardize CAVD in vitro research. Here we report that in calcification media containing organic phosphate, termed osteogenic media (OM), primary human VICs exhibited a passage-dependent decrease in calcification potential, which was not observed in calcification media containing inorganic phosphate, termed pro-calcifying media (PM). We used Alizarin red staining to compare the calcification potential of VICs cultured in OM and PM between the first and fourth passages after cell isolation from human CAVD tissues. Human VICs showed consistent Alizarin red stain when cultured with PM in a passage-independent manner. VICs cultured in OM did not exhibit consistent calcification potential between donors in early passages and consistently lacked positive Alizarin red stain in late passages. We performed whole cell, cytoplasmic and nuclear fractionation proteomics to identify factors regulating VIC passage-dependent calcification in OM. Proteomics cluster analysis identified tissue non-specific alkaline phosphatase (TNAP) as a regulator of passage-dependent calcification in OM. We verified an association of TNAP activity with calcification potential in VICs cultured in OM, but not in PM in which VICs calcified independent of TNAP activity. This study demonstrates that media culture conditions and cell passage impact the calcification potential of primary human VICs and should be taken into consideration in cell culture models of CAVD. Our results help standardize CAVD modeling as part of a greater effort to identify disease driving mechanisms and therapeutics for this unmet medical need.

Type 2 diabetes mellitus increases long-term mortality risk after isolated surgical aortic valve replacement

BACKGROUND

Diabetes mellitus (DM) adversely affects morbidity and mortality for major atherosclerosis-related cardiovascular diseases and is associated with increased risk for the development of aortic stenosis. Clinical data regarding the impact of DM on outcomes of patients undergoing aortic valve replacement (AVR) have revealed inconsistent results. The aim of the current study was to investigate and compare the impact of type 2 DM on short-, intermediate- and long-term mortality between DM and non-DM patients who undergo isolated AVR.

METHODS

We performed an observational study in a large tertiary medical center over a 14-year period (2004-2018), which included all patients who had undergone isolated AVR surgery for the first time. Of the 1053 study patients, 346 patients (33%) had type 2 DM (DM group) and were compared with non-DM (non-DM group) patients (67%). Short-term (in-hospital), intermediate (1- and 3-years), and late (5- and 10-years) mortality were evaluated. Mean follow-up of was 69 ± 43 months.

RESULTS

Short-term (in-hospital) mortality was similar between the DM compared with the non-DM group: 3.5% and 2.5% (p = 0.517). Intermediate-term mortality (1- and 3-year) was higher in the DM group compared with the non-DM group, but did not reach statistical significance: 8.1% vs. 5.7% (p = 0.169) and 12.1% vs. 8.3% (p = 0.064) respectively. Long-term (5- and 10-year) mortality was significantly higher in the DM group, compared to the non-DM group: 19.4% vs. 12.9% (p = 0.007) and 30.3% vs. 23.5% (p = 0.020) respectively. Among the 346 DM patients, 55 (16%) were treated with insulin and 291 (84%) with oral antiglycemic medication only. Overall in-hospital mortality among insulin-treated DM patients was 7.3% compared with 2.7% among non insulin-treated DM patients (p = 0.201). Long-term mortality was higher in the subgroup of insulin-treated DM patients compared with the subgroup of non-insulin treated DM patients with an overall mortality rate of 36.4% vs. 29.2% (p = 0.039). Furthermore, predictors for late mortality included DM (HR 1.39 CI 1.03-1.86, p = 0.031) and insulin treatment (HR 1.76 CI 1.05-2.94, p = 0.033), as demonstrated after adjustment for confounders by multivariable analysis.

CONCLUSIONS

Type 2 DM is an independent predictor for long-term mortality after isolated AVR surgery.

Impact of type 2 diabetes mellitus in the utilization and in-hospital outcomes of surgical aortic valve replacement in Spain (2001-2015)

BACKGROUND

The aims of this study were to examine trends in the incidence and in-hospital outcomes of SAVR among T2DM patients from 2001 to 2015, to compare clinical variables among T2DM patients and matched non-T2DM patients hospitalized for SAVR and to identify factors associated with in-hospital mortality (IHM) among T2DM patients.

METHODS

We performed a retrospective study using the Spanish National Hospital Discharge Database, 2001-2015. We included patients who had SAVR as the procedure in their discharge report. For each T2DM patient, we selected a sex-, age-, implanted valve type- and year-matched nondiabetic patient.

RESULTS

We identified 78,223 patients who underwent SAVR (23.49% with T2DM). The prevalence of T2DM increased significantly (p < 0.001) from 16.7% in 2001-2003 to 23.5% in 2012-2015. The incidence of SAVR increased significantly from 28.99 cases in 2001 to 65.79 cases in 2015 per 100,000 individuals in the T2DM population. Using Poisson regression models, we found that the incidence of SAVR was 2.60 times higher among patients with T2DM than among those without diabetes (IRR 2.60; 95% CI 2.56-2.65). The incidence of mechanical SAVR among T2DM patients remained stable from 2001 to 2015, and bioprosthetic SAVR rose from 8.29 to 41.74 cases per 100,000 individuals in the T2DM patient population (p < 0.001). We matched 8835 and 9543 patients who underwent mechanical and bioprosthetic SAVR, respectively. IHM decreased over time in T2DM patients and non-T2DM patients (from 8.89% and 7.81% to 3.88% and 5.07%, respectively). IHM was significantly lower in T2DM patients than in nondiabetic subjects who underwent bioprosthetic SAVR (4.77% vs. 6.04%, p < 0.001), with similar results obtained for mechanical valves (7.11% and 7.77%).

CONCLUSIONS

The incidence of SAVR was higher in T2DM patients, and the incidence of bioprosthetic SAVR increased significantly among T2DM subjects. IHM decreased over time, regardless of the existence or absence of T2DM and the valve type. IHM was significantly lower in T2DM patients than in nondiabetic patients who underwent bioprosthetic SAVR.

Placental Vascular Calcification and Cardiovascular Health: It Is Time to Determine How Much of Maternal and Offspring Health Is Written in Stone

Vascular calcification is the deposition of calcium phosphate minerals in vascular tissue. Vascular calcification occurs by both active and passive processes. Extent and tissue-specific patterns of vascular calcification are predictors of cardiovascular morbidity and mortality. The placenta is a highly vascularized organ with specialized vasculature that mediates communication between two circulatory systems. At delivery the placenta often contains calcified tissue and calcification can be considered a marker of viral infection, but the mechanisms, histoanatomical specificity, and pathophysiological significance of placental calcification are poorly understood. In this review, we outline the current understanding of vascular calcification mechanisms, biomedical consequences, and therapeutic interventions in the context of histoanatomical types. We summarize available placental calcification data and clinical grading systems for placental calcification. We report on studies that have examined the association between placental calcification and acute adverse maternal and fetal outcomes. We then review the intersection between placental dysfunction and long-term cardiovascular health, including subsequent occurrence of maternal vascular calcification. Possible maternal phenotypes and trigger mechanisms that may predispose for calcification and cardiovascular disease are discussed. We go on to highlight the potential diagnostic value of placental calcification. Finally, we suggest avenues of research to evaluate placental calcification as a research model for investigating the relationship between placental dysfunction and cardiovascular health, as well as a biomarker for placental dysfunction, adverse clinical outcomes, and increased risk of subsequent maternal and offspring cardiovascular events.

Increased Calcific Aortic Valve Disease in response to a diabetogenic, procalcific diet in the LDLr-/-ApoB100/100 mouse model

OBJECTIVE

Calcific aortic valve disease (CAVD) is a major cause of aortic stenosis (AS) and cardiac insufficiency. Patients with type II diabetes mellitus (T2DM) are at heightened risk for CAVD, and their valves have greater calcification than nondiabetic valves. No drugs to prevent or treat CAVD exist, and animal models that might help identify therapeutic targets are sorely lacking. To develop an animal model mimicking the structural and functional features of CAVD in people with T2DM, we tested a diabetogenic, procalcific diet and its effect on the incidence and severity of CAVD and AS in the, LDLr-/-ApoB100/100 mouse model.

RESULTS

LDLr-/-ApoB100/100 mice fed a customized diabetogenic, procalcific diet (DB diet) developed hyperglycemia, hyperlipidemia, increased atherosclerosis, and obesity when compared with normal chow fed LDLr-/-ApoB100/100 mice, indicating the development of T2DM and metabolic syndrome. Transthoracic echocardiography revealed that LDLr-/-ApoB100/100 mice fed the DB diet had 77% incidence of hemodynamically significant AS, and developed thickened aortic valve leaflets and calcification in both valve leaflets and hinge regions. In comparison, normal chow (NC) fed LDLr-/-ApoB100/100 mice had 38% incidence of AS, thinner valve leaflets and very little valve and hinge calcification. Further, the DB diet fed mice with AS showed significantly impaired cardiac function as determined by reduced ejection fraction and fractional shortening. In vitro mineralization experiments demonstrated that elevated glucose in culture medium enhanced valve interstitial cell (VIC) matrix calcium deposition.

CONCLUSIONS

By manipulating the diet we developed a new model of CAVD in T2DM, hyperlipidemic LDLr-/-ApoB100/100 that shows several important functional, and structural features similar to CAVD found in people with T2DM and atherosclerosis including AS, cardiac dysfunction, and inflamed and calcified thickened valve cusps. Importantly, the high AS incidence of this diabetic model may be useful for mechanistic and translational studies aimed at development of novel treatments for CAVD.

Advances in Pathophysiology of Calcific Aortic Valve Disease Propose Novel Molecular Therapeutic Targets

Calcific Aortic Valve Disease (CAVD) is the most common heart valve disease and its incidence is expected to rise with aging population. No medical treatment so far has shown slowing progression of CAVD progression. Surgery remains to this day the only way to treat it. Effective drug therapy can only be achieved through a better insight into the pathogenic mechanisms underlying CAVD. The cellular and molecular events leading to leaflets calcification are complex. Upon endothelium cell damage, oxidized LDLs trigger a proinflammatory response disrupting healthy cross-talk between valve endothelial and interstitial cells. Therefore, valve interstitial cells transform into osteoblasts and mineralize the leaflets. Studies have investigated signaling pathways driving and connecting lipid metabolism, inflammation and osteogenesis. This review draws a summary of the recent advances and discusses their exploitation as promising therapeutic targets to treat CAVD and reduce valve replacement.