Higher ambulatory blood pressure is associated with aortic valve calcification in the elderly: a population-based study

Effect of Blood Pressure Levels on Sinus Hemodynamics in Relation to Calcification After Bioprosthetic Aortic Valve Replacement

Coexisting hypertension and aortic stenosis are common. Some studies showed that elevated blood pressures may be associated with progression of calcific aortic valve disease (CAVD) while others showed no correlation. Flow dynamics in the sinuses of Valsalva are considered key factors in the progression of CAVD. While the relationship between hemodynamics and CAVD is not yet fully understood, it has been demonstrated that they are tightly correlated. This study aims to investigate the effect of changing systolic and diastolic blood pressures (SBP and DBP, respectively) on sinus hemodynamics in relation to potential initiation or progression of CAVD after aortic valve replacement (AVR). Evolut R, SAPIEN 3 and Magna valves were deployed in an aortic root under pulsatile conditions. Using particle image velocimetry, the hemodynamics in the sinus were assessed. The velocity, vorticity, circulation ( Γ ) and shear stress were calculated. This study shows that under elevated SBP and DBP, velocity, vorticity, and shear stress nearby the leaflets increased. Additionally, larger fluctuations of Γ and area under the curve throughout the cardiac cycle were observed. Elevated blood pressures are associated with higher velocity, vorticity, and shear stress near the leaflets which may initiate or accelerate pro-calcific changes in the prosthetic leaflets leading to bioprosthetic valve degeneration.

Factors associated with the progression of aortic valve calcification in older adults

BACKGROUND

Aortic valve calcification (AVC) is a common valvular abnormality that predisposes to stenosis; AVC progression and factors associated with it remain unclear. We investigated the association of clinical factors and serum biomarkers with AVC progression in a population-based cohort of older adults.

METHODS

Participants enrolled in both the Cardiovascular Abnormalities and Brain Lesion study (CABL; years 2005-2010) and the Subclinical Atrial Fibrillation And Risk of Ischemic Stroke study (SAFARIS;2014-2019) represent the study cohort. AVC was defined as bright dense echoes >1 mm in size on ≥1 cusps; each cusp was graded on a scale of 0 (normal) to 3 (severe calcification) at baseline and follow up. Serum biomarkers were measured at the time of follow-up assessment.

RESULTS

373 participants (mean 68.1 ± 7.6 years of age, 146 M/ 227F) were included. 139 (37%) had AVC progression;93 (25%) had mild progression (1 grade), and 46 (12%) had moderate-severe progression (≥2 grades). The only significant clinical predictor of any progression was the use of anti-hypertensive medication which was associated with older age, higher BMI and more frequent hypertension, diabetes and hyperlipidemia. In multivariable analysis including biomarkers, transforming growth factor beta 1 (TGF-β1) was significantly associated with both all and moderate-severe AVC progression.

CONCLUSIONS

A significant number of elderly subjects with AVC show progression of their valve disease; individual vascular risk factors are not associated with AVC progression, although a combined effect may exist. Higher levels of TGF-β1 are observed in individuals with AVC progression.

Sex-specific correlates of valvular and arterial calcification burden in patients with moderate aortic stenosis

INTRODUCTION

There are significant sex differences in the prevalence and severity of cardiac calcifying processes. Women harbour more severe mitral annular calcification (MAC), while men exhibit worse aortic valve (AVC) and coronary artery (CAC) calcification. To better understand these differences, we investigated the correlates of cardiac calcification according to sex.

METHODS

We conducted a cross-sectional study of 406 patients with ≥mild aortic stenosis (AS) defined by an aortic valve area ≤1.5 cm², a peak aortic jet velocity >2.0 m/s, or a mean transvalvular gradient >15 mm Hg. Doppler-echocardiography and non-contrast multidetector CT were performed concomitantly to assess AS and cardiac calcifications.

RESULTS

Mean age was 71±11 years and 33% were women. The AS haemodynamics were not significantly different between sexes (all p>0.50), with a mean indexed aortic valve area of 0.59±0.21 cm²/m², peak aortic jet velocity of 2.78 (2.37-3.68) m/s, and mean gradient of 17.9 (12.8-31.3) mm Hg for the whole cohort. Compared with men, women harboured lower AVC (480 (222-1191) vs 1003 (484-2329) Agatston unit, AU; p<0.0001) and CAC (366 (50-914) vs 618 (167-1357) AU; p=0.007), but more severe MAC (60 (1-887) vs 48 (0-351) AU; p=0.08) and ascending aorta calcification (227 (43-863) vs 142 (7-493) AU; p=0.03). After comprehensive adjustment, sex remained an independent predictor of each cardiac calcification subtype (all p<0.02) except for the ascending aorta (p=0.32). In multivariable analysis, certain variables, like age or bicuspid aortic valve, were associated with the calcification scores in both sexes. Sex-specific predictors of calcification burden were absence of angiotensin receptor blockers (β=-0.26; p=0.007) and renal impairment (β=0.26; p=0.003) for AVC, and bisphosphonates (β=0.20; p=0.05) for CAC in women; coronary artery disease (β=0.25; p=0.001) for AVC, and angiotensin receptor blockers (β=0.19; p=0.02) and calcium/vitamin D (β=0.15; p=0.02) for MAC in men.

CONCLUSION

In AS, factors associated with cardiac valvular and arterial calcification differ between sexes, suggesting an important contributory role of sex in the pathophysiology of these calcifying processes.

Global burden of calcific aortic valve disease and attributable risk factors from 1990 to 2019

Background

Calcific aortic valve disease (CAVD) was highly prevalent among developed countries and caused numerous deaths. Based on the Global Burden of Disease 2019, this study was designed to present comprehensive epidemiological information, attributable risks, and relevant factors.

Methods

All data were available online via the Global Health Data Exchange (GHDx). In this study, we analyzed the global incidence, prevalence, deaths, and disability-adjusted life years (DALYs) of CAVD across different regions from 1990 to 2019. We applied the estimated annual percentage changes (EAPCs) to evaluate the change trends and their attributable risks. In addition, we explored several relevant factors.

Results

From 1990 to 2019, the incidence cases, prevalence cases, CAVD-related deaths, and DALYs of CAVD gradually increased globally. However, the age-standardized death rate (ASDR) was relatively stable, and the age-standardized DALYs rate gradually declined during the past 30 years. Males and elderly individuals were more likely to suffer from CAVD. High systolic blood pressure (SBP) was the predominant attributable risk of disease burden that presented a global downward trend (death: EAPC = -0.68, 95% CI -0.77~-0.59, P < 0.001; DALYs: EAPC = -0.99, 95% CI -1.09 to -0.89, P < 0.001). Alcohol consumption (R = 0.79, P < 0.001), smoking prevalence (R = 0.75, P < 0.001), and calcium (R = 0.72, P < 0.001) showed a positive correlation with the age-standardized incidence rate (ASIR), whereas classic monsoon region (R = -0.68, P < 0.001) and mean temperature (R = -0.7, P < 0.001) showed a negative correlation with age-standardized incidence rate (ASIR). Besides, medical and healthcare resources presented a positive correlation with ASIR. Meanwhile, similar relationships were found in age-standardized prevalence rate (ASPR), ASDR, and age-standardized DALY rate (ASDALYR).

Conclusion

CAVD displays widely varied spatial distribution around the world, of which high SDI regions have the highest burdens. Age is a powerful factor and hypertension a predominant attributable risk factor. Moreover, controlling blood pressure, avoiding smoking, reducing alcohol consumption, and so on, could effectively reduce the burden of CAVD.

Aortic valve sclerosis and subclinical LV dysfunction in the general population with normal LV geometry

AIMS

Aortic valve sclerosis (AVS) without hemodynamically significant obstruction is related to cardiovascular morbidity and mortality independent of left ventricular (LV) hypertrophy, although the underlying mechanisms remain unknown. This study investigated the prevalence of AVS and its association with subclinical LV systolic and diastolic dysfunction in individuals with normal LV geometry free of cardiovascular disease.

METHODS

We examined 962 participants with normal LV geometry and free from significant AV stenosis who underwent standard and speckle-tracking echocardiography. AVS was categorized into 4 groups as follows: no AVS, AV thickening, calcification on one leaflet and calcification on ≥2 leaflets.

RESULTS

Among the 962 participants, 767 (79.7%) individuals were classified as no AVS, 74 (7.7%) as AV thickening, 87 (9.0%) as calcification on one leaflet, and 34 (3.5%) as calcification on ≥2 leaflets. The prevalence of subclinical LV diastolic dysfunction (E/e' ratio ≥13) and systolic dysfunction (LV global longitudinal strain (GLS) > -17.0% for men and > -18.0% for women) were greater in AVS groups than those in no AVS group. Subclinical LV diastolic impairment was evident from AV thickening and systolic dysfunction was observed at AV calcification. Multivariable logistic regression analysis demonstrated that AV thickening as well as calcification were independently associated with subclinical LV diastolic impairment (all p < 0.05), while only AV calcification on ≥2 leaflets conferred significant increased risk of impaired LVGLS.

CONCLUSIONS

AVS was observed in approximately 20% individuals without cardiac disease and was associated with subclinical LV diastolic and systolic function even in the absence of LV morphological change.

Association of serum levels of calcium, phosphate, and vitamin D with risk of developing aortic stenosis: the UK Biobank cohort

AIMS

This study was aimed to investigate the associations of serum calcium, phosphate, and vitamin D levels with the risk of developing aortic stenosis (AS).

METHODS AND RESULTS

We included 296 415 participants who were free of prior diagnosis of any valvular heart disease from the UK Biobank. Serum levels of phosphate, calcium, and vitamin D were measured. Incidental AS was determined by the records of hospital data. Cox regression was used to examine the association of serum mineral levels with incidental AS after adjustment for potential confounders. The mean age was 56.4 years (SD 8.14) and 53.3% of participants were women. During an average follow-up of 8.1 years, 1232 individuals developed AS. After adjustment, each 0.5-unit increase in serum phosphate level was associated with a 50% increase of AS risk (hazard ratio 1.50, 95% confidence interval 1.26-1.80). We observed no association of serum calcium and vitamin D levels with AS.

CONCLUSION

Increased serum phosphate level, but not calcium or vitamin D, was associated with a higher risk of incident AS, this association did not differed substantially between patients with and without decreased kidney function. This finding implied that phosphate may be a potential interventional target for AS.

Association of ambulatory blood pressure with aortic valve and coronary artery calcification

OBJECTIVE

We aimed to investigate the effect of ambulatory blood pressure (BP) on aortic valve calcification (AVC) and coronary artery calcification (CAC), which are subclinical atherosclerotic diseases.

METHODS

In this population-based, cross-sectional study, we assessed office BP, mean ambulatory BP (24-h, awake, and asleep), and variability of ambulatory BP, as determined by the coefficient of variation (awake and asleep). AVC and CAC were quantified using an Agatston score (>0) based on computed tomography scanning. We calculated relative risks (RRs) and 95% confidence intervals (CIs) with a 1-standard deviation increment in each BP index for the presence of AVC and CAC using a multivariate-adjusted Poisson regression with robust error variance.

RESULTS

Of 483 participants (mean age: 66.8 years), 154 (31.9%) and 310 (64.2%) had AVC and CAC, respectively. The presence of AVC was associated with office systolic BP (SBP; RR, 1.15; 95% CI, 1.03-1.28), awake diastolic BP (DBP) variability (RR, 1.12; 95% CI, 1.01-1.25), and asleep SBP variability (RR, 1.14; 95% CI, 1.03-1.27). The presence of CAC was associated with office SBP (RR, 1.08; 95% CI, 1.01-1.15), mean 24-h SBP (RR, 1.10; 95% CI, 1.04-1.16), mean awake SBP (RR, 1.11; 95% CI, 1.04-1.17), mean asleep SBP (RR, 1.07; 95% CI, 1.01-1.13), and asleep SBP variability (RR, 1.07; 95% CI, 1.01-1.13).

CONCLUSION

These findings highlight the association of ambulatory BP indices with both AVC and CAC, but with different effects on their presences.

Cumulative incidence and predictors of acquired aortic stenosis in a large population of men followed for up to 43 years

Background

Acquired aortic stenosis (AS) increases with age and has high mortality without intervention. Factors predicting its development are unclear, although atherosclerotic factors are assumed to be involved. Our aim in this study is to estimate the lifetime cumulative incidence and predictors of AS in middle-aged men.

Methods

We included a random sample of men (n = 9998) born 1915–1925 in Gothenburg, Sweden. From them, 7,494 were examined and followed until a diagnosis of AS or death (maximum follow-up time 42.8 years). We identified AS diagnosis from the Swedish National Patient Registry and deaths from the Swedish Cause of Death Registry by using International Classification of Disease (ICD) diagnostic criteria. To study time-dependent relationships between AS and risk factors with death as the competing risk, we divided the cohort into three overlapping follow-up groups: 25–43, 30–43 and 35–43 years. We used age-adjusted Cox proportional hazards model to identify predictors of AS.

Results

The lifelong cumulative incidence of AS was 3.2%. At baseline, participants in the third group had a healthier lifestyle, lower body mass index (BMI), blood pressure, and serum cholesterol levels. Higher BMI, obesity, cholesterol, hypertension, atrial fibrillation, smoking and heredity for stroke were associated with AS. With BMI of 20–22.5 as a reference, hazard ratios of being diagnosed with AS for men with a baseline BMI of 25–27.5 kg/m², 27.5–30 kg/m² and > 30 kg/m² were 1.99 (95% CI 1.12–3.55), 2.98 (95% CI 1.65–5.40) and 3.55 (95% CI 1.84–6.87), respectively.

Conclusions

The lifetime cumulative incidence of AS in middle-aged male population was 3.2%. Multiple atherosclerotic risk factors, particularly high BMI might be associated with a higher risk of developing AS.

Towards Personalized Therapy of Aortic Stenosis

Calcific aortic stenosis (CAS) is the most common cause of acquired valvular heart disease in adults with no available pharmacological treatment to inhibit the disease progression to date. This review provides an up-to-date overview of current knowledge of molecular mechanisms underlying CAS pathobiology and the related treatment pathways. Particular attention is paid to current randomized trials investigating medical treatment of CAS, including strategies based on lipid-lowering and antihypertensive therapies, phosphate and calcium metabolism, and novel therapeutic targets such as valvular oxidative stress, coagulation proteins, matrix metalloproteinases, and accumulation of advanced glycation end products.

Low Relative Valve Load is Associated With Paradoxical Low-Flow Aortic Stenosis Despite Preserved Left Ventricular Ejection Fraction and Adverse Clinical Outcomes

BACKGROUND

Paradoxical low-flow (LF) severe aortic stenosis (AS) despite preserved left ventricular (LV) ejection fraction (LVEF) has been shown to be distinct from normal-flow (NF) AS, with a poorer prognosis. Relative valve load (RVL) is a novel echocardiographic haemodynamic index based on the ratio of transaortic mean pressure gradient to the global valvulo-arterial impedance (Zva) in order to estimate the contribution of the valvular afterload to the global LV load. We aimed to determine the usefulness of RVL in LF AS versus NF AS.

METHOD

A total of 450 consecutive patients with medically managed severe AS (aortic valve area <1.0 cm²) with preserved LVEF (>50%) were studied. Patients were divided into LF (stroke volume index <35 mL/m²) or NF, and high RVL or low RVL. Baseline clinical and echocardiographic profiles, as well as clinical outcomes, were compared.

RESULTS

There were 149 (33.1%) patients with LF. Despite higher global impedance in LF (Zva 6.3±2.4 vs 3.9±0.9 mmHg/mL/m²; p<0.001) compared with NF, the RVL in LF AS was significantly lower (5.4±2.7 vs 9.8±5.1 mL/m²; p<0.001). On multivariable analysis, low RVL (≤7.51) remained independently associated with poor clinical outcomes on Cox regression (hazard ratio, 1.31; 95% confidence interval, 1.03-1.68), with 53.2% sensitivity and 70.3% specificity. This was comparable to other prognostic indices in AS. Kaplan-Meier curves demonstrated that low RVL was associated with increased mortality.

CONCLUSIONS

Increased systemic arterial afterload may be important in the pathophysiology of LF AS. Low RVL was an independent predictor of poor clinical outcomes in medically managed severe AS. There may be a greater role in the attenuation of systemic arterial afterload in AS to improve outcomes.

Hypertension in aortic stenosis: a focused review and recommendations for clinical practice

: In patients with aortic stenosis, the presence of hypertension negatively affects the hemodynamic severity of the stenosis, and worsens adverse left ventricular remodeling. It accelerates the progression of the stenosis and is associated with worse prognosis. Proper management of hypertension is thus crucial but there are concerns about the safety and efficacy of antihypertensive medications as well as uncertainty about optimal blood pressure (BP) targets and their impact on left ventricular mass regression and survival benefits. In the present review, we discuss these issues based on the evidence available in the current literature. Focus is first directed on the consequences of a persistently elevated BP before and after surgical aortic valve replacement or transcatheter valve implantation, and the clinical significance of an abnormal BP response during exercise in patients with significant aortic stenosis. Available data on use of antihypertensive drugs are then critically addressed, the conclusion being that calcium channel blockers may be associated with lower survival, and that diuretics may have disadvantages in patients with left ventricular hypertrophy and smaller left ventricular cavity dimensions, β-blockers may be well tolerated and a better choice for patients with concomitant coronary artery disease and arrhythmias. Renin--angiotensin system blockers improve survival given either before or after valve intervention. Emphasis is placed on the fact that evidence is not derived from randomized trials but only from observational studies. Finally, we discuss the optimal SBP level to reach in patients with aortic stenosis. Again, randomized trials are not available but observational evidence suggests that values between 130 and 139 mmHg systolic and 70-90 mmHg diastolic might represent the best option, and lower BP targets should probably be avoided.

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.

ZSF1 rat as animal model for HFpEF: Development of reduced diastolic function and skeletal muscle dysfunction

AIMS

The prevalence of heart failure with preserved ejection fraction (HFpEF) is still increasing, and so far, no pharmaceutical treatment has proven to be effective. A key obstacle for testing new pharmaceutical substances is the availability of suitable animal models for HFpEF, which realistically reflect the clinical picture. The aim of the present study was to characterize the development of HFpEF and skeletal muscle (SM) dysfunction in ZSF1 rats over time.

METHODS AND RESULTS

Echocardiography and functional analyses of the SM were performed in 6-, 10-, 15-, 20-, and 32-week-old ZSF1-lean and ZSF1-obese. Furthermore, myocardial and SM tissue was collected for molecular and histological analyses. HFpEF markers were evident as early as 10 weeks of age. Diastolic dysfunction, confirmed by a significant increase in E/e', was detectable at 10 weeks. Increased left ventricular mRNA expression of collagen and BNP was detected in ZSF1-obese animals as early as 15 and 20 weeks, respectively. The loss of muscle force was measurable in the extensor digitorum longus starting at 15 weeks, whereas the soleus muscle function was impaired at Week 32. In addition, at Week 20, markers for aortic valve sclerosis were increased.

CONCLUSIONS

Our measurements confirmed the appearance of HFpEF in ZSF1-obese rats as early as 10 weeks of age, most likely as a result of the pre-existing co-morbidities. In addition, SM function was reduced after the manifestation of HFpEF. In conclusion, the ZSF1 rat may serve as a suitable animal model to study pharmaceutical strategies for the treatment of HFpEF.

Simultaneous influence of sex and age on blood pressure difference between supine and sitting body positions

OBJECTIVES

Doctors' offices and outpatient departments typically measure blood pressure (BP) with the patient in a sitting position, whereas inpatient departments also use the supine position. As sex and age influence the autonomic function associated with BP regulation our study compared BP measurements in supine and sitting positions for men and women of different ages.

METHODS

We included 91 men and 118 women (≥18 years) without severe diseases. Hypertension was not an exclusion criterion because it is common in older persons. Mean left brachial BP and heart rate were determined by a digital sphygmomanometer in supine position as well as in sitting position before and after hand force measurement.

RESULTS

In a supine position women had slightly lower diastolic BP values than men. After sitting up, the diastolic BP increased in nearly all subjects. This increase was greater in women older than 50 years than for aged-matched men. In contrast to diastolic BP the systolic BP increased after sitting up in only two thirds of the subjects. Especially in women younger than 50 years the systolic BP often did not increase but decreased in response to postural change. The pulse pressure was mostly reduced after sitting up. This reduction was more pronounced in women than men independent of age and physical effort (i.e. hand force measurement). The sitting position also caused an increased heart rate, which was independent of sex and age.

CONCLUSION

Postural changes in the systolic and diastolic BP simultaneously depend on sex and age that needs to be considered for BP measurements in supine and sitting body positions.

Aortic Stenosis, Aortic Regurgitation and Arterial Hypertension

BACKGROUND

Hypertension (HT) is an important risk factor for cardiovascular disease and might precipitate pathology of the aortic valve.

OBJECTIVE

To investigate the association of HT with aortic dysfunction (including both aortic regurgitation and stenosis) and the impact of antihypertensive treatment on the natural course of underlying aortic disease.

METHODS

We performed a systematic review of the literature for all relevant articles assessing the correlation between HT and phenotype of aortic disease.

RESULTS

Co-existence of HT with aortic stenosis and aortic regurgitation is highly prevalent in hypertensive patients and predicts a worse prognosis. Certain antihypertensive agents may improve haemodynamic parameters (aortic jet velocity, aortic regurgitation volume) and remodeling of the left ventricle, but there is no strong evidence of benefit regarding clinical outcomes. Renin-angiotensin system inhibitors, among other vasodilators, are well-tolerated in aortic stenosis.

CONCLUSION

Several lines of evidence support a detrimental association between HT and aortic valve disease. Therefore, HT should be promptly treated in aortic valvulopathy. Despite conventional wisdom, specific vasodilators can be used with caution in aortic stenosis.

Management of patients with combined arterial hypertension and aortic valve stenosis: a consensus document from the Council on Hypertension and Council on Valvular Heart Disease of the European Society of Cardiology, the European Association of Cardiovascular Imaging (EACVI), and the European Association of Percutaneous Cardiovascular Interventions (EAPCI)

Aortic valve stenosis (AS) is the third most common cardiovascular disease. The prevalence of both AS and arterial hypertension increases with age, and the conditions therefore often co-exist. Co-existence of AS and arterial hypertension is associated with higher global left ventricular (LV) pressure overload, more abnormal LV geometry and function, and more adverse cardiovascular outcome. Arterial hypertension may also influence grading of AS, leading to underestimation of the true AS severity. Current guidelines suggest re-assessing patients once arterial hypertension is controlled. Management of arterial hypertension in AS has historically been associated with prudence and concerns, mainly related to potential adverse consequences of drug-induced peripheral vasodilatation combined with reduced stroke volume due to the fixed LV outflow obstruction. Current evidence suggests that patients should be treated with antihypertensive drugs blocking the renin-angiotensin-aldosterone system, adding further drug classes when required, to achieve similar target blood pressure (BP) values as in hypertensive patients without AS. The introduction of transcatheter aortic valve implantation has revolutionized the management of patients with AS, but requires proper BP management during and following valve replacement. The purpose of this document is to review the recent evidence and provide practical expert advice on management of hypertension in patients with AS.

Biomarkers Associated with Aortic Stenosis and Structural Bioprosthesis Dysfunction

Prediction of patients at risk of aortic valve stenosis (AS), AS progression rate, and aortic bioprosthesis dysfunction are of major importance for clinical management and/or prevention. Many imaging modalities may be used; however, they may not be conclusive or available for all patients. Circulating biomarkers are easily available and may be related to a disease or process such as aortic valve calcification or associated with a risk factor of the disease. This article reviews current blood biomarkers associated with aortic valve stenosis/calcification and bioprosthesis dysfunction.

Antihypertensive Treatment in Severe Aortic Stenosis

Previously, antihypertensive treatment in severe aortic stenosis was considered a relative contraindication. However, recent studies have shown that antihypertensive treatment may be safe and even beneficial in terms of reducing the progression of left ventricular pressure overload and even retarding the progression of valvular aortic stenosis. To date, no randomized clinical trials have been performed and no definite treatment guideline exist for the proper antihypertensive regimens. Antihypertensive treatment with β-blockers has generally been avoided in patients with severe aortic stenosis (AS) due to the concerns for inducing left ventricular dysfunction and hemodynamic compromise in the presence of severe outflow tract obstruction. Although it remains unclear whether antihypertensive treatment with a β-blocker is associated with increased risk of cardiovascular events in patients with AS, recent studies have shown that the use of β-blockers may be safe and may even be beneficial. Renin-angiotensin system (RAS) are upregulated in AS and have been shown to be involved in valve calcification and progression in both experimental models and in human trials. As such, theoretically, RAS inhibition would have benefit in retarding the progression of valvular stenosis as well as have benefit in left ventricle remodeling. Recent clinical studies are indeed showing that use of RAS inhibition may be beneficial in patients with AS. Future clinical trials to establish the ideal target blood pressure and antihypertensive regimens in severe AS is essential.

Medical Treatment of Aortic Stenosis

Untreated, severe, symptomatic aortic stenosis is associated with a dismal prognosis. The only treatment shown to improve survival is aortic valve replacement; however, before symptoms occur, aortic stenosis is preceded by a silent, latent phase characterized by a slow progression at the molecular, cellular, and tissue levels. In theory, specific medical therapy should halt aortic stenosis progression, reduce its hemodynamic repercussions on left ventricular function and remodeling, and improve clinical outcomes. In the present report, we performed a systematic review of studies focusing on the medical treatment of patients with aortic stenosis. Lipid-lowering therapy, antihypertensive drugs, and anticalcific therapy have been the main drug classes studied in this setting and are reviewed in depth. A critical appraisal of the preclinical and clinical evidence is provided, and future research avenues are presented.

Shear-Sensitive Genes in Aortic Valve Endothelium

SIGNIFICANCE

Currently, calcific aortic valve disease (CAVD) is only treatable through surgical intervention because the specific mechanisms leading to the disease remain unclear. In this review, we explore the forces and structure of the valve, as well as the mechanosensors and downstream signaling in the valve endothelium known to contribute to inflammation and valve dysfunction.

RECENT ADVANCES

While the valvular structure enables adaptation to dynamic hemodynamic forces, these are impaired during CAVD, resulting in pathological systemic changes. Mechanosensing mechanisms-proteins, sugars, and membrane structures-at the surface of the valve endothelial cell relay mechanical signals to the nucleus. As a result, a large number of mechanosensitive genes are transcribed to alter cellular phenotype and, ultimately, induce inflammation and CAVD. Transforming growth factor-β signaling and Wnt/β-catenin have been widely studied in this context. Importantly, NADPH oxidase and reactive oxygen species/reactive nitrogen species signaling has increasingly been recognized to play a key role in the cellular response to mechanical stimuli. In addition, a number of valvular microRNAs are mechanosensitive and may regulate the progression of CAVD.

CRITICAL ISSUES

While numerous pathways have been described in the pathology of CAVD, no treatment options are available to avoid surgery for advanced stenosis and calcification of the aortic valve. More work must be focused on this issue to lead to successful therapies for the disease.

FUTURE DIRECTIONS

Ultimately, a more complete understanding of the mechanisms within the aortic valve endothelium will lead us to future therapies important for treatment of CAVD without the risks involved with valve replacement or repair. Antioxid. Redox Signal. 25, 401-414.

Systolic hypertension and progression of aortic valve calcification in patients with aortic stenosis: results from the PROGRESSA study

AIMS

Hypertension is highly prevalent in patients with aortic stenosis (AS) and is associated with worse outcomes. The current prospective study assessed the impact of systolic hypertension (SHPT) on the progression of aortic valve calcification (AVC) measured by multidetector computed tomography (MDCT) in patients with AS.

METHODS AND RESULTS

The present analysis includes the first series of 101 patients with AS prospectively recruited in the PROGRESSA study. Patients underwent comprehensive Doppler echocardiography and MDCT exams at baseline and after 2-year follow-up. AVC and coronary artery calcification (CAC) were measured using the Agatston method. Patients with SHPT at baseline (i.e. systolic blood pressure ≥140 mmHg; n = 37, 37%) had faster 2-year AVC progression compared with those without SHPT (i.e. systolic blood pressure <140 mmHg) (AVC median [25th percentile-75th percentile]: +370 [126-824] vs. +157 [58-303] AU; P = 0.007, respectively). Similar results were obtained with the analysis of AVC progression divided by the cross-sectional area of the aortic annulus (AVC_density: +96 [34-218] vs. +45 [14-82] AU/cm², P = 0.01, respectively). In multivariable analysis, SHPT remained significantly associated with faster progression of AVC or AVC_density (all P = 0.001). There was no significant difference between groups with respect to progression of CAC (+39 [3-199] vs. +41 [0-156] AU, P = 0.88).

CONCLUSION

This prospective study shows for the first time that SHPT is associated with faster AVC progression but not with CAC progression in AS patients. These findings provide further support for the elaboration of randomized clinical trials to assess the efficacy of antihypertensive medication to slow the stenosis progression in patients with AS.

Arterial wave reflection and aortic valve calcification in an elderly community-based cohort

BACKGROUND

Aortic valve calcification (AVC) without stenosis is common in the elderly, is associated with cardiovascular morbidity and mortality, and may progress to aortic valve stenosis. Arterial stiffness and pulse-wave reflection are important components of proximal aortic hemodynamics, but their relationship with AVC is not established.

METHODS

To investigate the relationship of arterial wave reflection and stiffness with AVC, pulse wave analysis and AVC evaluation by echocardiography were performed in 867 participants from the Cardiovascular Abnormalities and Brain Lesions study. Participants were divided into four categories on the basis of the severity and extent of AVC: (1) none or mild focal AVC, (2) mild diffuse AVC, (3) moderate to severe focal AVC, and (4) moderate to severe diffuse AVC. Central blood pressures and pulse pressure, total arterial compliance, augmentation index, and time to wave reflection were assessed using applanation tonometry.

RESULTS

Indicators of arterial stiffness and wave reflection were significantly associated with AVC severity, except for central systolic and diastolic pressures and time to reflection. After adjustment for pertinent covariates (age, sex, race/ethnicity, and estimated glomerular filtration rate), only augmentation pressure (P = .02) and augmentation index (P = .002) were associated with the severity of AVC. Multivariate logistic regression analysis revealed that augmentation pressure (odds ratio per mm Hg, 1.14; 95% confidence interval, 1.02-1.27; P = .02) and augmentation index (odds ratio per percentage point, 1.07; 95% confidence interval, 1.01-1.13; P = .02) were associated with an increased risk for moderate to severe diffuse AVC, even when central blood pressure value was included in the same model.

CONCLUSIONS

Arterial wave reflection is associated with AVC severity, independent of blood pressure values. Increased contribution of wave reflection to central blood pressure could be involved in the process leading to AVC.