Why is aortic sclerosis associated with adverse clinical outcomes?

Mechanistic insights into fasting-induced autophagy in the aging heart

Autophagy is a prosurvival mechanism for the clearance of accumulated abnormal proteins, damaged organelles, and excessive lipids within mammalian cells. A growing body of data indicates that autophagy is reduced in aging cells. This reduction leads to various diseases, such as myocardial hypertrophy, infarction, and atherosclerosis. Recent studies in animal models of an aging heart showed that fasting-induced autophagy improved cardiac function and longevity. This improvement is related to autophagic clearance of damaged cellular components via either bulk or selective autophagy (such as mitophagy). In this editorial, we summarize the mechanisms of autophagy in normal and aging hearts. In addition, the protective effect of fasting-induced autophagy in cardiac aging has been highlighted.

Whole-Blood Transcriptome Unveils Altered Immune Response in Acute Myocardial Infarction Patients With Aortic Valve Sclerosis

BACKGROUND

Aortic valve sclerosis (AVSc) presents similar pathogenetic mechanisms to coronary artery disease and is associated with short- and long-term mortality in patients with coronary artery disease. Evidence of AVSc-specific pathophysiological traits in acute myocardial infarction (AMI) is currently lacking. Thus, we aimed to identify a blood-based transcriptional signature that could differentiate AVSc from no-AVSc patients during AMI.

METHODS

Whole-blood transcriptome of AVSc (n=44) and no-AVSc (n=66) patients with AMI was assessed by RNA sequencing on hospital admission. Feature selection, differential expression, and enrichment analyses were performed to identify gene expression patterns discriminating AVSc from no-AVSc and infer functional associations. Multivariable Cox regression analysis was used to estimate the hazard ratios of cardiovascular events in AVSc versus no-AVSc patients.

RESULTS

This cross-sectional study identified a panel of 100 informative genes capable of distinguishing AVSc from no-AVSc patients with 94% accuracy. Further analysis revealed significant mean differences in 143 genes, of which 30 genes withstood correction for age and previous AMI or coronary interventions. Functional inference unveiled a significant association between AVSc and key biological processes, including acute inflammatory responses, type I IFN (interferon) response, platelet activation, and hemostasis. Notably, patients with AMI with AVSc exhibited a significantly higher incidence of adverse cardiovascular events during a 10-year follow-up period, with a full adjusted hazard ratio of 2.4 (95% CI, 1.3-4.5).

CONCLUSIONS

Our findings shed light on the molecular mechanisms underlying AVSc and provide potential prognostic insights for patients with AMI with AVSc. During AMI, patients with AVSc showed increased type I IFN (interferon) response and earlier adverse cardiovascular outcomes. Novel pharmacological therapies aiming at limiting type I IFN response during or immediately after AMI might improve poor cardiovascular outcomes of patients with AMI with AVSc.

Aortic Valve Sclerosis in High-Risk Coronary Artery Disease Patients

Background: Current knowledge regarding the relationship between aortic valve sclerosis (AVSc), cardiovascular risk factors, and mortality in patients with known coronary artery disease (CAD) is still unclear. The present study aimed at investigating the prevalence of AVSc as well as its association with long-term all-cause mortality in high-risk CAD patients that has never been explored in large cohorts thus far.

Methods and Results: In this retrospective and observational cohort study we enrolled high-risk CAD patients, hospitalized at Centro Cardiologico Monzino (CCM), Milan, Italy, between January 2006 and December 2016. The morphology and function of the aortic valve were assessed from the recorded echocardiographic images to evaluate the presence of AVSc, defined as a non-uniform thickening of the aortic leaflets with no consequences on hemodynamics. Data on 5-year all-cause mortality was retrieved from a Regional database. Of the 5,489 patients initially screened, 4,938 (mean age 67 ± 11 years, 3,954 [80%] men) were enrolled in the study. In the overall population, AVSc was detected in 2,138 (43%) patients. Multivariable LASSO regression revealed that age, female gender, diabetes mellitus, previous MI, and left ventricular ejection fraction were independently associated with AVSc. All-cause mortality (adjusted hazard ratio: 1.29, 95%CI: 1.05–1.58) was significantly higher in AVSc than in non-AVSc patients.

Conclusions: AVSc is frequently detected in high-risk CAD patients and is associated with long-term mortality. Our findings corroborate the hypothesis that AVSc is an underestimated marker of systemic cardiovascular risk. Thus, AVSc detection may be used to improve long-term risk stratification of high-risk CAD patients.

All-cause and cardiovascular mortality in patients undergoing hemodialysis with aortic sclerosis and mild-to-moderate aortic stenosis: A cohort study

BACKGROUND AND AIMS

Mild-to-moderate aortic stenosis (AS) and aortic sclerosis, a precursor of AS, are associated with mortality in the general population; however, their association in patients undergoing hemodialysis with higher morbidity of AS is unknown. Thus, we investigated the mortality of aortic sclerosis and mild-to-moderate AS in patients undergoing hemodialysis.

METHODS

This was a retrospective multicenter cohort study of consecutive patients undergoing hemodialysis at nine dialysis facilities who underwent screening echocardiography between January 2008 and December 2019. We investigated the mortality of patients with aortic sclerosis or mild-to-moderate AS using multivariable Cox proportional hazards regression.

RESULTS

Among 1,878 patients undergoing hemodialysis, those with normal aortic valves, aortic sclerosis, mild AS, moderate AS, severe AS, and prosthetic aortic valves were 844 (45%), 793 (42%), 161 (8.6%), 38 (2.0%), 11 (0.6%), and 31 (1.7%), respectively. After excluding patients with severe AS and prosthetic aortic valves, we performed comparative analysis on 1,836 patients (mean age, 67 years; 66% male). In a median follow-up of 3.6 years, crude death rates (per 100 person-years) were 5.2, 10.6, and 13.0 in patients with normal aortic valves, aortic sclerosis, and mild-to-moderate AS, respectively. Compared with normal aortic valves, both aortic sclerosis and mild-to-moderate AS were associated with all-cause and cardiovascular death: adjusted hazard ratios (95% confidence intervals) were 1.36 (1.13-1.65) and 1.36 (1.02-1.80) for all-cause death; and 1.52 (1.06-2.17) and 1.74 (1.04-2.92) for cardiovascular death, respectively.

CONCLUSIONS

Aortic sclerosis and mild-to-moderate AS were independent risk factors for all-cause and cardiovascular death in patients undergoing hemodialysis.

TOR Signaling Pathway in Cardiac Aging and Heart Failure

Mechanistic Target of Rapamycin (mTOR) signaling is a key regulator of cellular metabolism, integrating nutrient sensing with cell growth. Over the past two decades, studies on the mTOR pathway have revealed that mTOR complex 1 controls life span, health span, and aging by modulating key cellular processes such as protein synthesis, autophagy, and mitochondrial function, mainly through its downstream substrates. Thus, the mTOR pathway regulates both physiological and pathological processes in the heart from embryonic cardiovascular development to maintenance of cardiac homeostasis in postnatal life. In this regard, the dysregulation of mTOR signaling has been linked to many age-related pathologies, including heart failure and age-related cardiac dysfunction. In this review, we highlight recent advances of the impact of mTOR complex 1 pathway and its regulators on aging and, more specifically, cardiac aging and heart failure.

The Role of Oxidative Stress in Cardiovascular Aging and Cardiovascular Diseases

Aging can be seen as process characterized by accumulation of oxidative stress induced damage. Oxidative stress derives from different endogenous and exogenous processes, all of which ultimately lead to progressive loss in tissue and organ structure and functions. The oxidative stress theory of aging expresses itself in age-related diseases. Aging is in fact a primary risk factor for many diseases and in particular for cardiovascular diseases and its derived morbidity and mortality. Here we highlight the role of oxidative stress in age-related cardiovascular aging and diseases. We take into consideration the molecular mechanisms, the structural and functional alterations, and the diseases accompanied to the cardiovascular aging process.

Non-coding RNAs and Cardiac Aging

Aging is an important risk factor for cardiovascular diseases. Aging increasing the morbidity and mortality in cardiovascular disease patients. With the society is aging rapidly in the world, medical burden of aging-related cardiovascular diseases increasing drastically. Hence, it is urgent to explore the underlying mechanism and treatment of cardiac aging. Noncoding RNAs (ncRNAs, including microRNAs, long noncoding RNAs and circular RNAs) have been reported to be involved in many pathological processes, including cell proliferation, cell death differentiation, hypertrophy and aging in wide variety of cells and tissues. In this chapter, we will summarize the physiology and molecular mechanisms of cardiac aging. Then, the recent research advances of ncRNAs in cardiac aging will be provided. The lessons learned from ncRNAs and cardiac aging studies would bring new insights into the regulatory mechanisms ncRNAs as well as treatment of aging-related cardiovascular diseases.

Association of Aortic Valve Sclerosis and Clinical Factors in Patients With Acute Myocardial Infarction

BACKGROUND

Since aortic valve sclerosis (AVS) and coronary artery disease (CAD) share similar cardiovascular risk factors, we hypothesized that the clinical profile of patients with acute myocardial infarction (AMI) would be worse in the presence of AVS. The aim of this study was to investigate the association between AVS and clinical factors in patients with AMI.

METHODS

Three hundred and fifteen patients with AMI were consecutively enrolled in the study. Echocardiography was used to assess the aortic valve morphology and left ventricular function. The extent and severity of CAD were assessed by Gensini score and the number of obstructed vessels. The patients were divided into 2 groups according to presence or absence of AVS.

RESULTS

The overall number of patients with AVS was 132 (41.9%). Patients with AVS were older (69.5 ± 11 vs. 59.5 ± 12 years, P < 0.00001). They also had a higher prevalence of hypertension (61% vs. 45%, P = 0.006), prior CAD (33% vs. 23%, P = 0.041), prior AMI (20% vs. 11%, P = 0.019) and a higher percentage were female (32% vs. 19%, P = 0.007) compared with AMI patients without AVS. There was no significant difference between the 2 groups with respect to the Gensini score (P = 0.372). Prior AMI was associated with AVS on age-adjusted logistic regression analyses. A multivariate analysis showed an independent association between the AVS and prior AMI and age (P < 0.0000001, P = 0.022, respectively).

CONCLUSIONS

Our results showed that the presence of AVS is associated with AMI recurrence.

Aortic valve sclerosis is associated with the extent of coronaryartery disease in stable coronary artery disease

BACKGROUND/AIM

Aortic valve sclerosis (AVS) is characterized by lipid deposition and calcific infiltration on the edge of aortic leaflets without significant restriction of motion. The SYNTAX Score (SS) is an important method for evaluating coronary artery disease (CAD). Many studies showed that there is an important relation between the SS and undesired cardiac outcomes. In our study, we investigated the correlation between the SS and AVS by including both ACS and stable CAD cases.

MATERIALS AND METHODS

We enrolled 543 patients with CAD who underwent coronary angiography into this cross-sectional study between September 2013 and September 2014.

RESULTS

The study population was divided into two groups according to SS values above and below 22. Diabetes mellitus (DM) incidence was greater in the group with high SS values (26.3% vs. 19.2%, P = 0.052.). Left ventricular ejection fraction (LVEF) and glomerular filtration rate were lower. Low-density lipoprotein cholesterol and triglyceride levels were lower while platelet counts were higher. In multivariate analysis, for the stable coronary artery group AVS existence, platelet count, LVEF value, and chronic obstructive pulmonary disease were found as independent predictors.

CONCLUSION

Our study results demonstrated that AVS is significantly associated with the complexity of CAD, especially in patients with stable CAD. This study provides new information regarding the role of AVS in CAD complexity.

Aortic valve sclerosis as a marker of atherosclerosis: Novel insights from hepatic steatosis

BACKGROUND

Nowadays, aortic valve sclerosis (AVSc) might be considered an atherosclerosis-like process due to significant association with age, male gender and some major features of metabolic syndrome. Nonalcoholic fatty liver disease (NAFLD) has been recognized as a clinical expression of the metabolic syndrome and as a predictor of cardiovascular events. We aim, with this meta-analysis, to evaluate the correlation between NAFLD and AVSc; this finding might suggest new insights and interactions among NAFLD, AVSc and the atherosclerotic process.

METHODS AND RESULTS

A detailed search was conducted according to Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines to identify all studies providing data about the association between AVSc and NAFLD. 3 studies enrolling a total of 1172 patients with NAFLD and 1467 controls without NAFLD were included in the meta-analysis. The prevalence of AVSc was 41.3% (95% CI: 32.0%, 51.4%) in NAFLD patients and 24.6% (18.4%, 32.0%) in subjects without NAFLD with a corresponding OR of 2.28 (95% CI: 1.21, 4.28, p=0.01, I(2): 77.6%, p=0.011). A meta-regression analysis showed that age, prevalence of male gender, hypertension, body mass index, and dyslipidemia were directly and significantly associated with the difference in the prevalence of AVSc between patients with NAFLD and those without.

CONCLUSIONS

In conclusion, our meta-analysis shows a significant association between NAFLD and AVSc. However, further evidence is needed to validate these findings and find out if there is a real link or just a mere association.

The effect of aortic wall and aortic leaflet stiffening on coronary hemodynamic: a fluid-structure interaction study

Pathologies of the aortic valve such as aortic sclerosis are thought to impact coronary blood flow. Recent clinical investigations have observed simultaneous structural and hemodynamic variations in the aortic valve and coronary arteries due to regional pathologies of the aortic valve. The goal of the present study is to elucidate this observed and yet unexplained phenomenon, in which a local pathology in the aortic valve region could potentially lead to the initiation or progression of coronary artery disease. Results revealed a considerable impact on the coronary flow, velocity profile, and consequently shear stress due to an increase in the aortic wall or aortic leaflet stiffness and thickness which concur with clinical observations. The cutoff value of 0.75 for fractional flow reserve was reached when the values of leaflet thickness and aortic wall stiffness were approximately twice and three times their normal value, respectively. Variations observed in coronary velocity profiles as well as wall shear stress suggest a possible link for the initiation of coronary artery disease.

Real-time imaging required for optimal echocardiographic assessment of aortic valve calcification

Introduction

Aortic valve calcification (AVC), even without haemodynamic significance, may be prognostically import as an expression of generalized atherosclerosis, but techniques for echocardiographic assessment are essentially unexplored.

Methods

Two-dimensional (2D) echocardiographic recordings (Philips IE33) of the aortic valve in short-axis and long-axis views were performed in 185 consecutive patients within 1 week before surgery for aortic stenosis (n = 109, AS), aortic regurgitation (n = 61, AR), their combination (n = 8) or dilation of the ascending aorta (n = 7). The grey scale mean (GSMn) of the aortic valve in an end-diastolic short-axis still frame was measured. The same frame was scored visually 1–5 as indicating that the aortic valve was normal, thick, or had mild, moderate or severe calcification. The visual echodensity of each leaflet was determined real time applying the same 5-grade scoring system for each leaflet, and the average for the whole valve was calculated. Finally, a similar calcification score for the whole valve based on inspection and palpation by the surgeon was noted.

Results

Visual assessment of real-time images using the proposed scoring system showed better correlation with the surgical evaluation of the degree of valve calcification (r = 0·83, P<0·001) compared to evaluation of stop frames by visual assessment (r = 0·66, P<0·001) or the GSMn score (r = 0·64, P<0·001). High inter- and intra-observer correlations were observed for real-time visual score (both intraclass correlation coefficient = 0·93).

Conclusion

Real-time evaluation of the level of AVC is superior to using stop frames assessed either visually or by dedicated computer grey scale measurement software.

Cardiac aging: from molecular mechanisms to significance in human health and disease

Cardiovascular diseases (CVDs) are the major causes of death in the western world. The incidence of cardiovascular disease as well as the rate of cardiovascular mortality and morbidity increase exponentially in the elderly population, suggesting that age per se is a major risk factor of CVDs. The physiologic changes of human cardiac aging mainly include left ventricular hypertrophy, diastolic dysfunction, valvular degeneration, increased cardiac fibrosis, increased prevalence of atrial fibrillation, and decreased maximal exercise capacity. Many of these changes are closely recapitulated in animal models commonly used in an aging study, including rodents, flies, and monkeys. The application of genetically modified aged mice has provided direct evidence of several critical molecular mechanisms involved in cardiac aging, such as mitochondrial oxidative stress, insulin/insulin-like growth factor/PI3K pathway, adrenergic and renin angiotensin II signaling, and nutrient signaling pathways. This article also reviews the central role of mitochondrial oxidative stress in CVDs and the plausible mechanisms underlying the progression toward heart failure in the susceptible aging hearts. Finally, the understanding of the molecular mechanisms of cardiac aging may support the potential clinical application of several "anti-aging" strategies that treat CVDs and improve healthy cardiac aging.

Aortic valve sclerosis and clinical outcomes: moving toward a definition

The presence of aortic valve sclerosis has been suggested as a marker of increased cardiovascular risk, including increased mortality. However, it remains unclear whether aortic valve sclerosis is independently associated with risk or merely a marker of coexistent cardiovascular risk factors. Aortic valve sclerosis is usually diagnosed on transthoracic echocardiography, the most widely used imaging modality in observational and natural history studies of aortic valve disease. Defining aortic valve sclerosis has remained challenging due to the variable and qualitative nature of its description by ultrasound techniques. Importantly, artifacts common to ultrasound imaging and awareness of demographic and clinical history information may bias the diagnosis of aortic valve sclerosis. Because clinicians may alter treatment recommendations or follow-up based on echocardiographic reporting of aortic valve sclerosis, highlighting pitfalls of the subjective nature by which aortic valve sclerosis is identified and establishing diagnostic criteria are necessary. This review describes the diagnostic criteria for aortic valve sclerosis used in outcome studies, summarizes the epidemiological findings reporting the relationship between aortic valve sclerosis and clinical outcome, and proposes a definition of aortic valve sclerosis based on the literature.

Relationship between platelet indices and aortic valve sclerosis

OBJECTIVE

Aortic valve sclerosis (AVS) is a progressive disease that is characterized by aortic valve thickening without causing significant narrowing and in which pathology resembles atherosclerotic coronary heart disease. We aimed to evaluate the relationship between AVS and platelet indices including mean platelet volume (MPV), platelet distribution weight (PDW), and platelet count.

METHOD

Two hundred ten patients who were evaluated in the echocardiography unit due to various reasons between January and October 2008 were consecutively included in the study. The patients were divided into 2 groups according to presence or absence of AVS. The patient group consisted of 150 patients (76 females and 74 males; mean age, 64.5 + or - 11.5 years). Patients without AVS (24 females and 36 males; mean age, 49.8 + or - 15.7 years) were assigned as control group. The MPV, PDW, and platelet count were measured.

RESULTS

The MPV (9.56 + or - 1.3 fL vs 9.15 + or - 1.0 fL, P = .022) and PDW (16.9 + or - 2.3% vs 14.9 +/- 2.3, P = .001) were significantly higher in patients with AVS (+) compared to the AVS (-) group. No significant difference was demonstrated between the groups in terms of white blood cell and platelet counts (P > .05). When the AVS (+) group was compared to the AVS (-) group, a significant difference was found in respect of hypertension, diabetes mellitus, and smoking status.

CONCLUSION

Platelet production indices including MPV and PDW were increased in patients with AVS. The complex interrelationship between increased platelet production indices and AVS and value of antithrombotic therapies in patients with AVS need to be evaluated in further studies.

Stage-related effect of statin treatment on the progression of aortic valve sclerosis and stenosis

It has been suggested that statins could slow the progression of aortic stenosis (AS), but this hypothesis is still debated and has not been validated in large series of patients by long-term follow-up studies. Moreover, information about the role of statins in patients with different degrees of severity of AS is scarce. From our 1988 to 2007 echocardiographic database, we retrospectively identified all asymptomatic patients with aortic valve sclerosis (abnormal irregular thickening of the aortic valve with a peak aortic velocity [Vmax] > or =1.5 and <2 m/s), mild AS (Vmax > or =2 and <3 m/s), and moderate AS (Vmax > or =3 and <4 m/s), age > or =50 years, and with > or =2 echocardiographic studies > or =2 years apart. Exclusion criteria were moderate/severe aortic regurgitation, bicuspid aortic valve, rheumatic valve disease, and ejection fraction <40%. The final study population consisted of 1,046 patients (mean age 70 +/- 8 years, 587 men); 309 were treated with statins. Mean follow-up duration was 5.6 +/- 3.2 years (range 2 to 19). Progression of AS was slower in patients receiving statins compared with untreated patients in aortic sclerosis (0.04 +/- 0.09 vs 0.07 +/- 0.10 m/s/year, p = 0.01) and mild AS (0.09 +/- 0.15 vs 0.15 +/- 0.15 m/s/year, p = 0.001), but not in moderate AS (0.21 +/- 0.18 vs 0.22 +/- 0.15 m/s/year, p = 0.70). In multivariate analysis only statin therapy, initial Vmax, and dialysis were independently related to progression of aortic valve disease. In conclusion, in a large series of patients with long-term follow-up, statins were effective in slowing the progression of aortic valve disease in aortic sclerosis and mild AS, but not in moderate AS. These results suggest that statin therapy should be taken into consideration in the early stages of this common disease.

Aortic valve sclerosis: is it a cardiovascular risk factor or a cardiac disease marker?

BACKGROUND

Aortic valve sclerosis, without stenosis, has been associated with an increased cardiovascular mortality and morbidity due to myocardial infarction. However, it is unclear whether it is a cardiovascular risk factor or a cardiac disease marker. The goal of our study is to evaluate the difference in the prevalence of cardiovascular disease and risk factors among patients with or without aortic sclerosis.

METHODS

This observational study compared a group of 142 consecutive subjects with aortic valve sclerosis, assigned as group S, with a group of 101 subjects without aortic sclerosis, assigned as group C. Patients with bicuspid aortic valves and those with antegrade Doppler velocity across aortic valve leaflets exceeding 2.0 m/sec were excluded.

RESULTS

Mean ages of groups S and C were 71 +/- 8, and 68.8 +/- 6 years, respectively (P value = not significant). The prevalence of smoking, diabetes, hypercholesterolemia, hypertension, pulse pressure, left ventricular diastolic dysfunction, atrial fibrillation, and stroke was not significantly different between the two groups. However, there was a significantly higher prevalence of left ventricular hypertrophy (P = 0.05), ventricular arrhythmias (P = 0.02), myocardial infarction (P = 0.04), and systolic heart failure (P = 0.04) in aortic sclerosis group.

CONCLUSIONS

Aortic sclerosis is associated with a higher prevalence of left ventricular hypertrophy, ventricular arrhythmias, myocardial infarction, and systolic heart failure, while the prevalence of cardiovascular risk factors is not different between aortic sclerosis patients and controls. Hence, aortic sclerosis represents a cardiac disease marker useful for early identification of high-risk patients beyond cardiovascular risk factors rate.

Aortic valve sclerosis is associated with preclinical cardiovascular disease in hypertensive adults: the Hypertension Genetic Epidemiology Network study

RATIONALE

Aortic valve sclerosis (AVS) has been associated with atherosclerosis and increased all-cause and cardiovascular death. However, whether AVS is associated with preclinical cardiovascular disease among adults at high risk because of hypertension has not been determined in a population-based sample.

METHODS AND RESULTS

Clinical and echocardiographic parameters were measured in 1624 hypertensive participants (54 +/- 11 years, 65% women, 63% black, 17% diabetic, 19% smokers) without significant valvular or cardiovascular diseases in the population-based Hypertension Genetic Epidemiology Network study. The 152 participants with AVS (9.4%), compared with participants without AVS, were older, more often white, male, treated for hypertension or hypercholesteromia (all P < 0.05) and had longer duration and worse hypertension, but did not differ in diabetes status, smoking or fenfluramine use. Adjusting for age, gender and race, the AVS group had higher total cholesterol/high-density lipoprotein-cholesterol (P < 0.05). Controlling for age, gender, race and other clinical covariates, AVS was independently associated with higher septal, posterior and relative wall thicknesses, isovolumic relaxation time and left atrial diameter, and with mild aortic regurgitation and mitral annular calcification (all P < 0.05).

CONCLUSIONS

In a population-based sample of hypertensive adults, AVS was prevalent (9.4%) and associated with a proatherogenic clinical profile and abnormal left ventricular geometry and filling, increased left atrial size and mitral annular calcification, which may contribute to the adverse prognosis associated with AVS.