Association of inflammation, myocardial fibrosis and cardiac remodelling in patients with mild aortic stenosis as assessed by biomarkers and echocardiography

Valvular heart disease and cardiomyopathy: reappraisal of their interplay

Cardiomyopathies and valvular heart diseases are typically considered distinct diagnostic categories with dedicated guidelines for their management. However, the interplay between these conditions is increasingly being recognized and they frequently coexist, as in the paradigmatic examples of dilated cardiomyopathy and hypertrophic cardiomyopathy, which are often complicated by the occurrence of mitral regurgitation. Moreover, cardiomyopathies and valvular heart diseases can have a shared aetiology because several genetic or acquired diseases can affect both the cardiac valves and the myocardium. In addition, the association between cardiomyopathies and valvular heart diseases has important prognostic and therapeutic implications. Therefore, a better understanding of their shared pathophysiological mechanisms, as well as of the prevalence and predisposing factors to their association, might lead to a different approach in the risk stratification and management of these diseases. In this Review, we discuss the different scenarios in which valvular heart diseases and cardiomyopathies coexist, highlighting the need for an improved classification and clustering of these diseases with potential repercussions in the clinical management and, particularly, personalized therapeutic approaches.

Novel Biomarkers and Advanced Cardiac Imaging in Aortic Stenosis: Old and New

Currently, the symptomatic status and left ventricular ejection fraction (LVEF) play a crucial role in aortic stenosis (AS) assessment. However, the symptoms are often subjective, and LVEF is not a sensitive marker of left ventricle (LV) decompensation. Over the past years, the cardiac structure and function research on AS has increased due to advanced imaging modalities and potential therapies. New imaging parameters emerged as predictors of disease progression in AS. LV global longitudinal strain has proved useful for risk stratification in asymptomatic severe AS patients with preserved LVEF. The assessment of myocardial fibrosis by cardiac magnetic resonance is the most studied application and offers prognostic information on AS. Moreover, the usage of biomarkers in AS as objective measures of LV decompensation has recently gained more interest. The present review focuses on the transition from compensatory LV hypertrophy (H) to LV dysfunction and the biomarkers associated with myocardial wall stress, fibrosis, and myocyte death. Moreover, we discuss the potential impact of non-invasive imaging parameters for optimizing the timing of aortic valve replacement and provide insight into novel biomarkers for possible prognostic use in AS. However, data from randomized clinical trials are necessary to define their utility in daily practice.

Transcatheter Aortic Valve Implantation in Cardiac Amyloidosis and Aortic Stenosis

Aortic stenosis (AS) and cardiac amyloidosis (CA) occur concomitantly in a significant number of patients and portend a higher risk of all-cause mortality. Previous studies have investigated outcomes in patients with concomitant CA/AS who underwent transcatheter aortic valve implantation (TAVI) versus medical therapy alone, but no evidence-based consensus regarding the ideal management of these patients has been established. Medline, Scopus, and Cochrane Central Register of Controlled Trials were systematically searched to identify relevant studies. Methodologic bias was assessed using the modified Newcastle-Ottawa scale for observational studies. A total of 4 observational studies comprising 83 patients were included. Of these, 45 patients (54%) underwent TAVI, whereas 38 (46%) were managed conservatively. Of the 3 studies that included baseline characteristics by treatment group, 30% were women. The risk of all-cause mortality was found to be significantly lower in patients who underwent TAVI than those treated with conservative medical therapy alone (odds ratio 0.24, 95% confidence interval 0.08 to 0.73). In conclusion, this meta-analysis suggests a lower risk of all-cause mortality in patients with CA with AS who underwent TAVI than those managed with medical therapy alone.

Pathogenesis and Molecular Immune Mechanism of Calcified Aortic Valve Disease

Calcified aortic valve disease (CAVD) was previously regarded as a passive process associated with valve degeneration and calcium deposition. However, recent studies have shown that the occurrence of CAVD is an active process involving complex changes such as endothelial injury, chronic inflammation, matrix remodeling, and neovascularization. CAVD is the ectopic accumulation of calcium nodules on the surface of the aortic valve, which leads to aortic valve thickening, functional stenosis, and ultimately hemodynamic disorders. CAVD has become an important cause of death from cardiovascular disease. The discovery of therapeutic targets to delay or block the progression of CAVD and the clinical application of transcatheter aortic valve implantation (TAVI) provide new ideas for the prevention and treatment of CAVD. This article summarizes the pathogenesis of CAVD and provides insight into the future directions of CAVD diagnosis and treatment.

Transthyretin cardiac amyloidosis in patients after TAVR: clinical and echocardiographic findings and long term survival

Aims

The aim of this study was to examine the prevalence of amyloid transthyretin (ATTR) cardiac amyloidosis in patients 1–2 years after trans‐catheter aortic valve replacement (TAVR) and to assess their clinical and echocardiographic outcome and long‐term survival.

Methods and results

We enrolled 88 patients, mean age 81 years, 534 (390–711) days after TAVR. Patients underwent a Tc99m‐PYP scintigraphy for the diagnosis of ATTR cardiac amyloidosis. Eleven (12.5%) participants were diagnosed with ATTR cardiac amyloidosis. Eighty eight per cent of patients without amyloidosis were in New York Heart Association Classes 1–2 after TAVR, compared with 64% patients with ATTR cardiac amyloidosis (P = 0.022). There were no differences in left ventricular (LV) ejection fraction (P = 0.69) between patients with and without ATTR cardiac amyloidosis at enrolment. The LV mass index and pulmonary artery pressure were significantly higher in patients with ATTR cardiac amyloidosis (P = 0.046 and P = 0.002, respectively). Global longitudinal strain and myocardial work efficiency were significantly lower in patients with ATTR cardiac amyloidosis (P = 0.031 and P = 0.048, respectively). We assessed changes in echocardiographic data, from the time of TAVR to enrolment, and as expected, there was a significant decrease in aortic valve gradient in both groups. There was a significant reduction in LV mass and LV mass index and improvement in basal segment LV strain in the ATTR cardiac amyloidosis negative group (P = 0.045, P = 0.046 and 0.023, respectively). However, in the ATTR cardiac amyloidosis group the change in LV mass and LV mass index and LV basal strain values was not significant (P = 0.24, P = 0.13 and P = 0.35, respectively). The were no significant changes in other echocardiographic parameters in both groups. The patients were followed for 1150 (1086–1221) days after enrolment. Twenty seven patients had at least one cardiac hospitalization during of follow up, of them seven were with ATTR cardiac amyloidosis and 20 patients without amyloidosis (P = 0.017). Eighteen patients (20%) died during follow up; 12 (14%) patients died due to cardiac causes. There was no difference in all‐cause and cardiac mortality between patients with and without ATTR cardiac amyloidosis (P = 0.6 and P = 0.53, respectively).

Conclusions

The long‐term survival after TAVR is not significantly affected by the presence of ATTR cardiac amyloidosis. However, the clinical course of these patients and the LV hemodynamic improvement is less favourable. This hypothesis‐generating study suggests screening for ATTR cardiac amyloidosis in patients who underwent TAVR and have limited clinical or echocardiographic improvement, because they may potentially improve with new therapies for ATTR cardiac amyolidosis.

Early Progression of Aortic Stenosis Associated With Iatrogenic Variant Transthyretin Amyloidosis After Domino Liver Transplantation

We report a 65-year-old man who underwent aortic valve replacement because of severe aortic stenosis associated with de novo iatrogenic variant transthyretin amyloidosis derived from a liver graft extracted from a patient with hereditary transthyretin amyloidosis 9 years after the domino liver transplantation. (Level of Difficulty: Advanced.).

Serum Matrix Metalloproteinases and Left Atrial Remodeling-The Hoorn Study

Extracellular matrix protein turnover may play an important role in left atrial (LA) remodelling. The aim is to investigate the associations between matrix metalloproteinase (MMPs), tissue inhibitor of metalloproteinase (TIMP-1) and LA volume index (LAVI) and if these associations are independent of TIMP-1 levels. Participants from The Hoorn Study, a population-based cohort study (n = 674), underwent echocardiography. Serum MMPs (i.e., MMP-1, MMP-2, MMP-3, MMP-9, and MMP-10) and TIMP-1 levels were measured with ELISA. Multiple linear regression analyses were used. MMP-1 levels were not associated with LAVI. Higher MMP-2 levels were associated with larger LAVI (regression coefficient per SD increase in MMP (95% CI); 0.03 (0.01; 0.05). Higher MMP-3 and MMP-9 levels were associated with smaller LAVI; −0.04 (−0.07; −0.01) and −0.04 (−0.06; −0.02) respectively. Only in women were higher MMP-10 levels associated with larger LAVI; 0.04 (0.00; 0.07, p-interaction 0.04). Additionally, only in women were higher TIMP-1 levels associated with smaller LAVI; −0.05 (−0.09; −0.01, p-interaction 0.03). The associations between MMPs and LAVI were independent of TIMP-1 levels. In conclusion, serum MMPs are associated with LAVI, independent of CVD risk factors and TIMP-1 levels. In addition, these associations differ according to sex and within MMP subgroups. This shows that the role of MMPs in LA remodelling is complex.

Circulating and tissue matricellular RNA and protein expression in calcific aortic valve disease

Aortic valve sclerosis is a highly prevalent, poorly characterized asymptomatic manifestation of calcific aortic valve disease and may represent a therapeutic target for disease mitigation. Human aortic valve cusps and blood were obtained from 333 patients undergoing cardiac surgery (n = 236 for severe aortic stenosis, n = 35 for asymptomatic aortic valve sclerosis, n = 62 for no valvular disease), and a multiplex assay was used to evaluate protein expression across the spectrum of calcific aortic valve disease. A subset of six valvular tissue samples (n = 3 for asymptomatic aortic valve sclerosis, n = 3 for severe aortic stenosis) was used to create RNA sequencing profiles, which were subsequently organized into clinically relevant gene modules. RNA sequencing identified 182 protein-encoding, differentially expressed genes in aortic valve sclerosis vs. aortic stenosis; 85% and 89% of expressed genes overlapped in aortic stenosis and aortic valve sclerosis, respectively, which decreased to 55% and 84% when we targeted highly expressed genes. Bioinformatic analyses identified six differentially expressed genes encoding key extracellular matrix regulators: TBHS2, SPARC, COL1A2, COL1A1, SPP1, and CTGF. Differential expression of key circulating biomarkers of extracellular matrix reorganization was observed in control vs. aortic valve sclerosis (osteopontin), control vs. aortic stenosis (osteoprotegerin), and aortic valve sclerosis vs. aortic stenosis groups (MMP-2), which corresponded to valvular mRNA expression. We demonstrate distinct mRNA and protein expression underlying aortic valve sclerosis and aortic stenosis. We anticipate that extracellular matrix regulators can serve as circulating biomarkers of early calcific aortic valve disease and as novel targets for early disease mitigation, pending prospective clinical investigations.

Less fibrosis in elderly subjects supplemented with selenium and coenzyme Q10-A mechanism behind reduced cardiovascular mortality?

BACKGROUND

In an intervention study where 221 healthy elderly persons received selenium and coenzyme Q10 as a dietary supplement, and 222 received placebo for 4 years we observed improved cardiac function and reduced cardiovascular mortality. As fibrosis is central in the aging process, we investigated the effect of the intervention on biomarkers of fibrogenic activity in a subanalysis of this intervention study.

MATERIAL AND METHODS

In the present subanalysis 122 actively treated individuals and 101 controls, the effect of the treatment on eight biomarkers of fibrogenic activity were assessed. These biomarkers were: Cathepsin S, Endostatin, Galectin 3, Growth Differentiation Factor-15 (GDF-15), Matrix Metalloproteinases 1 and 9, Tissue Inhibitor of Metalloproteinases 1 (TIMP 1) and Suppression of Tumorigenicity 2 (ST-2). Blood concentrations of these biomarkers after 6 and 42 months were analyzed by the use of T-tests, repeated measures of variance, and factor analyses.

RESULTS

Compared with placebo, in those receiving supplementation with selenium and coenzyme Q10, all biomarkers except ST2 showed significant decreased concentrations in blood. The changes in concentrations, that is, effects sizes as given by partial eta² caused by the intervention were considered small to medium.

CONCLUSION

The significantly decreased biomarker concentrations in those on active treatment with selenium and coenzyme Q10 compared with those on placebo after 36 months of intervention presumably reflect less fibrogenic activity as a result of the intervention. These observations might indicate that reduced fibrosis precedes the reported improvement in cardiac function, thereby explaining some of the positive clinical effects caused by the intervention. © 2017 BioFactors, 44(2):137-147, 2018.

Intermedin 1-53 Inhibits Myocardial Fibrosis in Rats by Down-Regulating Transforming Growth Factor-β

BACKGROUND Myocardial fibrosis is the result of persistent anoxia and ischemic myocardial fibers caused by coronary atherosclerotic stenosis, which lead to heart failure, threatening the patient's life. This study aimed to explore the regulatory role of intermedin 1-53 (IMD1-53) in cardiac fibrosis using neonatal rat cardiac fibroblasts and a myocardial infarction (MI) rat model both in vitro and in vivo. MATERIAL AND METHODS The Western blot method was used to detect the protein expression of collagen I and collagen III in myocardial fibroblasts. The SYBR Green I real-time quantitative polymerase chain reaction (PCR) assay was used to detect the mRNA expression of collagen type I and III, IMD1-53 calcitonin receptor-like receptor (CRLR), transforming growth factor-β (TGF-β), and matrix metalloproteinase-2 (MMP-2). Masson staining was used to detect the area changes of myocardial fibrosis in MI rats. RESULTS Results in vivo showed that IMD1-53 reduced the scar area on the heart of MI rats and inhibited the expression of collagen type I and III both in mRNA and protein. Results of an in vitro study showed that IMD1-53 inhibited the transformation of cardiomyocytes into myofibroblasts caused by angiotensin II (Ang II). The further mechanism study showed that IMD1-53 inhibited the expression of TGF-β and the phosphorylation of smad3, which further up-regulated the expression of MMP-2. CONCLUSIONS IMD1-53 is an effective anti-fibrosis hormone that inhibits cardiac fibrosis formation after MI by down-regulating the expression of TGF-β and the phosphorylation of smad3, blocking fibrous signal pathways, and up-regulating the expression of MMP-2, thereby demonstrating its role in regression of myocardial fibrosis.

Cardioprotective effects of rutin via alteration in TNF-α, CRP, and BNP levels coupled with antioxidant effect in STZ-induced diabetic rats

Diabetic cardiomyopathy (DCM) is a dreadful complication of diabetes responsible for 80 % mortality in diabetic patients, but unfortunately its pharmacotherapy is still incomplete. Rutin is a naturally occurring flavonoid having a long history of use in nutritional supplements for its action against oxidative stress, inflammation, and hyperglycemia, the key players involved in the progression of DCM, but remains unexplored for its role in DCM. This study was conducted to address this lacuna. It was performed in 4-week-old Streptozotocin-induced (45 mg/kg) diabetic rats for a period of 24 weeks to mimic the cardiotoxic effect of chronic hyperglycemia in diabetic patient's heart and to investigate the effect of rutin (50 mg/kg/day) in ameliorating these effects. Heart of the diabetic rats showed altered ECG parameters, reduced total antioxidant capacity, increased inflammatory assault, and degenerative changes. Interestingly, rutin treatment significantly ameliorated these changes with decrease in blood glucose level (p > 0.001), % HbA1c (p > 0.001) and reduced expression of TNF-α (p < 0.001), CRP (p < 0.001), and BNP (p < 0.01) compared to diabetic control rats. In addition, rutin provided significant protection against diabetes associated oxidative stress (p < 0.05), prevented degenerative changes in heart, and improved ECG parameters compared to diabetic control rats. The heart-to-body weight ratio was significantly reduced in rutin treatment group compared to diabetic control rats (p < 0.001). In conclusion, this study implicates that oxidative stress and inflammation are the central players involved in the progression of DCM and rutin ameliorates DCM through its antioxidant and anti-inflammatory actions on heart.