Impact of hypertension and renin-angiotensin system inhibitors in aortic stenosis

Angiotensin II receptor blockers are associated with reduced valvular fibrosis in females with aortic stenosis

BACKGROUND

Angiotensin receptor blockers (ARBs) may slow down the progression of aortic stenosis (AS), through their antifibrotic effect. Females present more valvular fibrosis than males, thus ARBs may have more effect in females. Our aim was to assess the impact of ARBs on the remodeling of the aortic valve in males and females.

METHODS

We included patients who had an aortic valve replacement± coronary bypass grafting between 2006-2013. Patients with missing echocardiographic or histologic data were excluded. Warren-Yong and fibrosis scores of the explanted valves were performed. Patients were divided into four phenotypes according to their Warren-Yong and fibrosis scores: Mild calcification/fibrosis group, Severe calcification/fibrosis group, Predominant fibrosis group, Predominant calcification group.

RESULTS

Among the 1,321 included patients, the vast majority (89%) has severe AS. Patients in the predominant fibrosis group, as compared to the predominant calcium group, were more often females (39 vs 31%, p=0.008), bicuspid valves (44 vs 34%, p=0.002) and they less often used ARBs (25 vs 30%, p=0.046). Female sex was independently associated with being in the predominant fibrosis group (OR 1.45 [95% CI 1.08-1.95], p=0.01), with a significant interaction between female sex and ARBs. Females taking ARBs compared to females not taking ARBs had significantly lower fibrosis score (p<0.001). This difference was not seen in males.

CONCLUSION

In this large series of patients with moderate-severe AS, among females there was a negative association between intake of ARBs and valvular fibrosis. Thus, the possible effects of ARBs may be sex-specific, with a larger therapeutic role in females.

Independent association of aortic stenosis with many known cardiovascular risk factors and many inflammatory diseases

BACKGROUND

Aortic valve stenosis is associated with age, rheumatic fever and bicuspid aortic valve, but its association with other co-morbidities, such as inflammatory disease and race/ethnicity, is less known.

AIM

To investigate any association between aortic stenosis and many co-morbidities.

METHODS

We used the large Nationwide Inpatient Sample database to evaluate any association between aortic stenosis and risk factors. We performed univariate and multivariable analyses, adjusting for co-morbid conditions.

RESULTS

Data were extracted from the first available database that used the International Classification of Diseases, Tenth Revision codes specifically coding for aortic stenosis alone, spanning from 2016 to 2020 (n=112,982,565). A total of 2,322,649 patients had aortic stenosis; the remaining 110,659,916 served as controls. We found a strong and independent significant association between aortic stenosis and coronary artery disease (odds ratio [OR]: 2.11, 95% confidence interval [CI]: 2.09-2.13), smoking (OR: 1.08, 95% CI: 1.07-1.08), diabetes mellitus (OR: 1.15, 95% CI: 1.14-1.16), hypertension (OR: 1.41, 95% CI: 1.4-1.42), hyperlipidaemia (OR: 1.31, 95% CI: 1.3-1.32), renal disease (OR: 1.3, 95% CI: 1.29-1.31), chronic obstructive pulmonary disease (OR: 1.05, 95% CI: 1.04-1.05), obesity (OR: 1.3, 95% CI: 1.29-1.32), white race/ethnicity (OR: 1.47, 95% CI: 1.42-1.52), rheumatoid arthritis (OR: 1.13, 95% CI: 1.11-1.15), scleroderma (OR: 1.93, 95% CI: 1.79-2.09), systemic connective tissue disease (OR: 1.24, 95% CI: 1.2-1.27), polyarteritis nodosa (OR: 1.5, CI: 1.24-1.81) and Raynaud's syndrome (OR: 1.16, 95% CI: 1.09-1.24) (all P<0.001), in addition to known factors, such as age, male sex and bicuspid aortic valve.

CONCLUSION

Using a very large database, we found many new associations with aortic valve stenosis, including race/ethnicity, renal disease, several inflammatory diseases, chronic obstructive pulmonary disease and obesity, in addition to many other known cardiovascular risk factors.

Renin-angiotensin system inhibitors reduce cardiovascular mortality in hypertensive patients with severe aortic stenosis undergoing transcatheter aortic valve implantation: insights from the EffecTAVI registry

Objectives

Arterial hypertension is associated with the triggering of the renin-angiotensin system, leading to left ventricle fibrosis and worse cardiovascular outcomes. In this study, patients with comorbid arterial hypertension and severe aortic stenosis (AS) undergoing transcatheter aortic valve implantation (TAVI) were selected from the EffecTAVI registry to evaluate the impact of angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin II receptor blockers (ARBs) on cardiovascular mortality.

Methods

We enrolled 327 patients undergoing TAVI from the EffecTAVI registry. Using Kaplan-Meier event rates and study-stratified multivariable Cox proportional hazards regression models, we evaluated 2-year clinical outcomes according to the ACEI/ARB therapy status at enrollment.

Results

Among the included patients, 222 (67.9%) were on ACEIs/ARBs at baseline, whereas 105 (32.1%) were not. Treatment with ACEIs/ARBs was significantly associated with a 2-year decrease in the rate of cardiovascular mortality (HR = 0.44, 95% CI: 0.23-0.81, p = 0.009). This association remained stable after both multivariable adjustment and propensity score matching.

Conclusion

In a cohort of hypertensive patients with severe AS who were selected from the EffecTAVI registry, ACEI/ARB treatment at baseline was found to be independently associated with a lower risk of 2-year cardiovascular mortality, suggesting a potential benefit of this treatment. More trials are needed to validate this finding and to understand the full benefit of this treatment.

Calcific aortic valve disease: mechanisms, prevention and treatment

Calcific aortic valve disease (CAVD) is the most common disorder affecting heart valves and is characterized by thickening, fibrosis and mineralization of the aortic valve leaflets. Analyses of surgically explanted aortic valve leaflets have shown that dystrophic mineralization and osteogenic transition of valve interstitial cells co-occur with neovascularization, microhaemorrhage and abnormal production of extracellular matrix. Age and congenital bicuspid aortic valve morphology are important and unalterable risk factors for CAVD, whereas additional risk is conferred by elevated blood pressure and plasma lipoprotein(a) levels and the presence of obesity and diabetes mellitus, which are modifiable factors. Genetic and molecular studies have identified that the NOTCH, WNT-β-catenin and myocardin signalling pathways are involved in the control and commitment of valvular cells to a fibrocalcific lineage. Complex interactions between valve endothelial and interstitial cells and immune cells promote the remodelling of aortic valve leaflets and the development of CAVD. Although no medical therapy is effective for reducing or preventing the progression of CAVD, studies have started to identify actionable targets.

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.

The clinical outcomes of reni-angiotensin system inhibitors for patients after transcatheter aortic valve replacement: A systematic review and meta-analysis

Aims

The objective of our systematic reviews and meta-analysis is to evaluate the clinical outcomes of RAS inhibitors for patients after TAVR.

Methods and results

We performed a comprehensive search for Embase, Pubmed, and Cochrane databases from inception to May 1, 2022. The analysis of all outcomes was performed using the random-effects model. In total, 7 articles with a total of 32,585 patients (RAS inhibitor, N = 14,871; Controls, N = 17,714) were included in our study. There was a significantly lower rates of all-cause mortality (RR = 0.76, 95%Cl = 0.68 to 0.86, P &lt; 0.01), cardiovascular death (RR = 0.66, 95%Cl = 0.59–0.74, P &lt; 0.01) and HF readmission (RR = 0.87, 95%Cl = 0.80–0.94, P &lt; 0.01) in patients with RAS inhibitors compared with controls. Patients with RAS inhibitors also had lower rates of all-cause mortality (RR = 0.82, 95%Cl = 0.76–0.89, P &lt; 0.01) and cardiovascular death (RR = 0.73, 95%Cl, 0.62–0.85, P &lt; 0.01) after propensity matching.

Conclusions

In conclusion, our systematic reviews and meta-analysis demonstrated that RAS inhibitors could improve the clinical outcomes for patients after TAVR. Further large and high-quality trials should be conducted to support the use of RAS inhibitors for patients after TAVR.

The mechanistic pathways of oxidative stress in aortic stenosis and clinical implications

Despite the elucidation of the pathways behind the development of aortic stenosis (AS), there remains no effective medical treatment to slow or reverse its progress. Instead, the gold standard of care in severe or symptomatic AS is replacement of the aortic valve. Oxidative stress is implicated, both directly as well as indirectly, in lipid infiltration, inflammation and fibro-calcification, all of which are key processes underlying the pathophysiology of degenerative AS. This culminates in the breakdown of the extracellular matrix, differentiation of the valvular interstitial cells into an osteogenic phenotype, and finally, calcium deposition as well as thickening of the aortic valve. Oxidative stress is thus a promising and potential therapeutic target for the treatment of AS. Several studies focusing on the mitigation of oxidative stress in the context of AS have shown some success in animal and in vitro models, however similar benefits have yet to be seen in clinical trials. Statin therapy, once thought to be the key to the treatment of AS, has yielded disappointing results, however newer lipid lowering therapies may hold some promise. Other potential therapies, such as manipulation of microRNAs, blockade of the renin-angiotensin-aldosterone system and the use of dipeptidylpeptidase-4 inhibitors will also be reviewed.

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.

Calcium-Dependent Cytosolic Phospholipase A2α as Key Factor in Calcification of Subdermally Implanted Aortic Valve Leaflets

Calcium-dependent cytosolic phospholipase A2α (cPLA2α) had been previously found to be overexpressed by aortic valve interstitial cells (AVICs) subjected to in vitro calcific induction. Here, cPLA2α expression was immunohistochemically assayed in porcine aortic valve leaflets (iAVLs) that had undergone accelerated calcification subsequent to 2- to 28-day-long implantation in rat subcutis. A time-dependent increase in cPLA2α-positive AVICs paralleled mineralization progression depending on dramatic cell membrane degeneration with the release of hydroxyapatite-nucleating acidic lipid material, as revealed by immunogold particles decorating organelle membranes in 2d-iAVLs, as well as membrane-derived lipid byproducts in 7d- to 28d-iAVLs. Additional positivity was detected for (i) pro-inflammatory IL-6, mostly exhibited by rat peri-implant cells surrounding 14d- and 28d-iAVLs; (ii) calcium-binding osteopontin, with time-dependent increase and no ossification occurrence; (iii) anti-calcific fetuin-A, mostly restricted to blood plasma within vessels irrorating the connective envelopes of 28d-iAVLs; (iv) early apoptosis marker annexin-V, limited to sporadic AVICs in all iAVLs. No positivity was found for either apoptosis executioner cleaved caspase-3 or autophagy marker MAP1. In conclusion, cPLA2α appears to be a factor characterizing AVL calcification concurrently with a distinct still uncoded cell death form also in an animal model, as well as a putative target for the prevention and treatment of calcific valve diseases.

Evaluating Medical Therapy for Calcific Aortic Stenosis: JACC State-of-the-Art Review

Despite numerous promising therapeutic targets, there are no proven medical treatments for calcific aortic stenosis (AS). Multiple stakeholders need to come together and several scientific, operational, and trial design challenges must be addressed to capitalize on the recent and emerging mechanistic insights into this prevalent heart valve disease. This review briefly discusses the pathobiology and most promising pharmacologic targets, screening, diagnosis and progression of AS, identification of subgroups that should be targeted in clinical trials, and the need to elicit the patient voice earlier rather than later in clinical trial design and implementation. Potential trial end points and tools for assessment and approaches to implementation and design of clinical trials are reviewed. The efficiencies and advantages offered by a clinical trial network and platform trial approach are highlighted. The objective is to provide practical guidance that will facilitate a series of trials to identify effective medical therapies for AS resulting in expansion of therapeutic options to complement mechanical solutions for late-stage disease.

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.

Arterial Hypertension in Aortic Valve Stenosis: A Critical Update

Aortic stenosis (AS) is a very common valve disease and is associated with high mortality once it becomes symptomatic. Arterial hypertension (HT) has a high prevalence among patients with AS leading to worse left ventricle remodeling and faster degeneration of the valve. HT also interferes with the assessment of the severity of AS, leading to an underestimation of the real degree of stenosis. Treatment of HT in AS has not historically been pursued due to the fear of excess reduction in afterload without a possibility of increasing stroke volume due to the fixed aortic valve, but most recent evidence shows that several drugs are safe and effective in reducing BP in patients with HT and AS. RAAS inhibitors and beta-blockers provide benefit in selected populations based on their profile of pharmacokinetics and pharmacodynamics. Different drugs, on the other hand, have proved to be unsafe, such as calcium channel blockers, or simply not easy enough to handle to be recommended in clinical practice, such as PDE5i, MRA or sodium nitroprusside. The present review highlights all available studies on HT and AS to guide antihypertensive treatment.

Calcific aortic valve disease: from molecular and cellular mechanisms to medical therapy

Calcific aortic valve disease (CAVD) is a highly prevalent condition that comprises a disease continuum, ranging from microscopic changes to profound fibro-calcific leaflet remodelling, culminating in aortic stenosis, heart failure, and ultimately premature death. Traditional risk factors, such as hypercholesterolaemia and (systolic) hypertension, are shared among atherosclerotic cardiovascular disease and CAVD, yet the molecular and cellular mechanisms differ markedly. Statin-induced low-density lipoprotein cholesterol lowering, a remedy highly effective for secondary prevention of atherosclerotic cardiovascular disease, consistently failed to impact CAVD progression or to improve patient outcomes. However, recently completed phase II trials provide hope that pharmaceutical tactics directed at other targets implicated in CAVD pathogenesis offer an avenue to alter the course of the disease non-invasively. Herein, we delineate key players of CAVD pathobiology, outline mechanisms that entail compromised endothelial barrier function, and promote lipid homing, immune-cell infiltration, and deranged phospho-calcium metabolism that collectively perpetuate a pro-inflammatory/pro-osteogenic milieu in which valvular interstitial cells increasingly adopt myofibro-/osteoblast-like properties, thereby fostering fibro-calcific leaflet remodelling and eventually resulting in left ventricular outflow obstruction. We provide a glimpse into the most promising targets on the horizon, including lipoprotein(a), mineral-binding matrix Gla protein, soluble guanylate cyclase, dipeptidyl peptidase-4 as well as candidates involved in regulating phospho-calcium metabolism and valvular angiotensin II synthesis and ultimately discuss their potential for a future therapy of this insidious disease.

Cardiologic Long-Term Follow-Up of Patients Treated With Chest Radiotherapy: When and How?

Introduction: Radiotherapy may cause valvular (VHD), pericardial, coronary artery disease (CAD), left ventricular dysfunction (LVD), arrhythmias. The risk of radiation induced heart disease (RIHD) increases over time. The current guidelines suggest a screening for RIHD every 5 years in the long-term survivors who had been treated by chest RT.

Methods: We reviewed the clinical and instrumental data of 106 patients diagnosed with RIHD. In one group (Group A: 69 patients) RIHD was diagnosed in an asymptomatic phase through a screening with ECG, echocardiogram and stress test. A second group (37 patients) was seen when RIHD was symptomatic. We compared the characteristics of the two groups at the time of RT, of RIHD detection and at last follow-up.

Results: Overall, 64 patients (60%) had CAD (associated to other RIHD in 18); 39 (36.7%) had LVD (isolated in 20); 24 (22.6%) had VHD (isolated in 10 cases). The interval between the last negative test and the diagnosis of moderate or severe RIHD was <5 years in 26 patients, and <4 years in 18. In group A, 63% of the patients with CAD had silent ischemia. The two groups did not differ with regard to type of tumor, cardiovascular risk factors, use of anthracycline-based chemotherapy, age at RT treatment, radiation dose and interval between RT and toxicity detection. The mean time from RT and RIHD was 16 years in group A and 15 in group B. Interventional therapy at RIHD diagnosis was more frequent in group B (54 vs. 30%, p < 0.05). At last follow-up, 27 patients had died (12 of cancer, 9 of cardiac causes, 6 of other causes); mean ejection fraction was 60% in group A and 50% in group B (p < 0.01). Patients with ejection fraction ≤ 50% were 14.5% in group A and 40% in group B (p < 0.01).

Conclusions: Clinically relevant RIHD become evident at a mean interval of 16 years after RT. The most frequent clinical manifestations are CAD and LVD. RIHD diagnosis in asymptomatic patients may preserve their cardiac function with timely interventions. We suggest -after 10 years from radiotherapy- a screening every 2–3 years.

Aortic Valve Calcification Score in Patients with Arterial Hypertension Environmentally Exposed to Tobacco Smoke

The objective of our study was to determine the relationship between exposure to environmental tobacco smoke (ETS) and the value of the aortic valve calcification score (AVCS) in people suffering from arterial hypertension (AH). 107 non-smokers with AH (mean age 67.16 ± 8.48 years) were qualified for the study. The degree of exposure to ETS was assessed using the Second-hand Smoke Exposure Scale (SHSES) questionnaire. Study group was divided depending on ETS exposure: A—no exposure, B—low, C—medium and D—high. AVCS was measured based on the aortic valve plane multiplanar reconstruction from the non-contrast phase of the cardiac computed tomography. The Agatston algorithm was used, in which calcifications were considered changes with a density exceeding 130 HU. The mean AVCS value in the study group of patients was 213.59 ± 304.86. The AVCS was significantly lower in subgroup A than in subgroups C and D. In subgroup A, the lack of aortic valve calcification (AVCS = 0) was observed significantly more frequently than in subgroups C and D. There was a positive correlation between the number of SHSES points and the AVCS value (r = 0.37, p < 0.05). Based on the ROC curve, the SHSES value was determined as the optimal cut-off point for the prediction of AVCS = 0, amounting to 3 points. The accuracy of SHSES < 3 as the predictor of AVCS = 0 was set at 62.18%. Hypertensive patients have an unfavourable relationship between the amount of exposure to ETS, determined on the SHSES scale, and the AVCS value.

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.

Impact of renin-angiotensin system inhibitors on clinical outcomes in patients with severe aortic stenosis undergoing transcatheter aortic valve replacement: an analysis of from the PARTNER 2 trial and registries

AIMS

Left ventricular pressure overload is associated with activation of the cardiac renin-angiotensin system, which may contribute to myocardial fibrosis and worse clinical outcomes. We sought to assess the association between treatment with angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin II receptor blockers (ARBs) at baseline and clinical outcomes in patients with symptomatic, severe aortic stenosis (AS) undergoing transcatheter aortic valve replacement (TAVR) in the PARTNER 2 trial and registries.

METHODS AND RESULTS

A total of 3979 intermediate, high, or prohibitive risk patients who underwent TAVR in the PARTNER 2 trial and registries (excluding the valve in valve registry) were included in the study. Clinical outcomes at 2 years were compared according to baseline ACEI/ARB treatment status using Kaplan-Meier event rates and study-stratified multivariable Cox proportional hazards regression models. Sensitivity analysis was conducted using propensity score matching. Of 3979 patients who were included in the current analysis, 1736 (43.6%) were treated and 2243 (56.4%) were not treated with ACEI/ARB at baseline. Treatment with ACEI/ARB was associated with lower 2-year all-cause mortality (18.6% vs. 27.5%, P < 0.0001), cardiovascular mortality (12.3% vs. 17.9%, P < 0.0001), and non-cardiovascular mortality (7.2% vs. 11.7%, P < 0.0001). Angiotensin-converting enzyme inhibitor/ARB treatment at baseline remained independently associated with a lower hazard of 2-year all-cause and cardiovascular mortality after multivariable adjustment, and propensity score matching.

CONCLUSION

In a large cohort of patients with severe symptomatic AS from the PARTNER 2 trial and registries, ACEI/ARB treatment at baseline was independently associated with a lower risk of 2-year all-cause and cardiovascular mortality.

Inflammatory and Biomechanical Drivers of Endothelial-Interstitial Interactions in Calcific Aortic Valve Disease

Calcific aortic valve disease is dramatically increasing in global burden, yet no therapy exists outside of prosthetic replacement. The increasing proportion of younger and more active patients mandates alternative therapies. Studies suggest a window of opportunity for biologically based diagnostics and therapeutics to alleviate or delay calcific aortic valve disease progression. Advancement, however, has been hampered by limited understanding of the complex mechanisms driving calcific aortic valve disease initiation and progression towards clinically relevant interventions.

Safety and efficacy of angiotensin-converting enzyme inhibitors in aortic stenosis: A protocol for systematic review and meta-analysis

BACKGROUND

Although there are many studies showing potential benefit in aortic stenosis (AS) patients taking angiotensin-converting enzyme inhibitors (ACEI), but these studies are subject to significant selection and other biases, making the results challenging to interpret. Furthermore, the evidence on the use of ACEI in AS patients has not been reviewed systematically; we thus conducted this protocol assess the clinical effectiveness and safety of ACEI for patients with AS.

METHODS

The following search terms will be used in PUBMED, Scopus, EMBASE, and Cochrane Library databases on May, 2021, as the search algorithm: (angiotensin-converting enzyme inhibitors) OR (ACEI) AND (aortic stenosis) OR (AS). Two searchers will independently draft and carry out the search strategy, and the third member will further complete it. The studies on cohort study focusing on assessing the efficacy of ACEI on AS patients will be included in our meta-analysis. At least one of the following outcomes should have been measured: left ventricular mass, exercise tolerance, B-type natriuretic peptide, adverse event, functional outcomes, and aortic valve area. All outcomes are pooled on random-effect model. A P value of <.05 is considered to be statistically significant.

RESULTS

The results of this research will be delivered in a peer-reviewed journal.

CONCLUSION

Depending on the previous studies, we assumed that ACEI could possibly improve the clinical symptoms and outcomes of symptomatic AS.

SYSTEMATIC REVIEW REGISTRATION NUMBER

10.17605/OSF.IO/G9KPT.

Calcified Aortic Valve Disease in Patients With Familial Hypercholesterolemia

Familial hypercholesterolemia (FH) is a rare autosomal gene deficiency disease with increased low-density lipoprotein cholesterol, xanthoma, and premature coronary heart disease. Calcified aortic valve disease (CAVD) is prevalent in FH patients, resulting in adverse events and heavy health care burden. Aortic valve calcification is currently considered an active biological process, which shares several common risk factors with atherosclerosis, including aging, hypertension, dyslipidemia, and so on. Unfortunately, the pathogenesis and therapy of CAVD in FH are still controversial. There is no pharmacological intervention recommended to delay the development of CAVD in FH, and the only effective treatment for severe CAVD is aortic valve replacement. In this review, we summarize the detailed description of the pathophysiology, molecular mechanism, risk factors, and treatment of CAVD in FH patients.

Current Evidence and Future Perspectives on Pharmacological Treatment of Calcific Aortic Valve Stenosis

Calcific aortic valve stenosis (CAVS), the most common heart valve disease, is characterized by the slow progressive fibro-calcific remodeling of the valve leaflets, leading to progressive obstruction to the blood flow. CAVS is an increasing health care burden and the development of an effective medical treatment is a major medical need. To date, no effective pharmacological therapies have proven to halt or delay its progression to the severe symptomatic stage and aortic valve replacement represents the only available option to improve clinical outcomes and to increase survival. In the present report, the current knowledge and latest advances in the medical management of patients with CAVS are summarized, placing emphasis on lipid-lowering agents, vasoactive drugs, and anti-calcific treatments. In addition, novel potential therapeutic targets recently identified and currently under investigation are reported.

Antihypertensive therapies in moderate or severe aortic stenosis: a systematic review and meta-analysis

BACKGROUND

Hypertension confers a poor prognosis in moderate or severe aortic stenosis (AS), however, antihypertensive therapy (AHT) is often not prescribed due to the perceived deleterious effects of vasodilation and negative inotropes.

OBJECTIVE

To assess the efficacy and safety outcomes of AHT in adults with moderate or severe AS.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

The Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE and grey literature were searched without language restrictions up to 9 September 2019.

STUDY ELIGIBILITY CRITERIA, APPRAISAL AND SYNTHESIS METHODS

Two independent reviewers performed screening, data extraction and risk of bias assessments from a systematic search of observational studies and randomised controlled trials comparing AHT with a placebo or no AHT in adults with moderate or severe AS for any parameter of efficacy and safety outcomes. Conflicts were resolved by the third reviewer. Meta-analysis with pooled effect sizes using random-effects model, were estimated in R.

MAIN OUTCOME MEASURES

Mortality, Left Ventricular (LV) Mass Index, systolic blood pressure, diastolic blood pressure and LV ejection fraction RESULTS: From 3025 publications, 31 studies (26 500 patients) were included in the qualitative synthesis and 24 studies in the meta-analysis. AHT was not associated with mortality when all studies were pooled, but heterogeneity was substantial across studies. The effect size of AHT differed according to drug class. Renin-angiotensin-aldosterone system inhibitors (RAASi) were associated with reduced risk of mortality (Pooled HR 0.58, 95% CI 0.43 to 0.80, p=0.006), The differences in changes of haemodynamic or echocardiographic parameters from baseline with and without AHT did not reach statistical significance.

CONCLUSION

AHT appears safe, is well tolerated. RAASi were associated with clinical benefit in patients with moderate or severe AS.

Renin-Angiotensin System Blockade in Aortic Stenosis: Implications Before and After Aortic Valve Replacement

Aortic stenosis (AS) is a common valvular heart disease in the aging population that is characterized by a variable period of asymptomatic phase before development of symptoms and severe AS. Mortality and morbidity is substantial even after aortic valve replacement, in part related to persistent left ventricular hypertrophy, diastolic dysfunction, and heart failure. Renin-angiotensin system (RAS) blockade therapy is associated with modulation of adverse left ventricular remodeling, reduction in myocardial hypertrophy, and fibrosis, resulting in clinical improvements in patients with congestive heart failure There are emerging data to suggest benefit of RAS blockade in patients with AS before and after AVR with regard to potentially slower progression of aortic valve calcification, left ventricular mass and survival benefit in favor of RAS blockade group before AVR, and also survival benefit in patients after AVR. We review the available data to understand the role of RAS blockade before AVR and in patients undergoing surgical AVR and transcatheter AVR. There are significant survival advantages of RAS inhibition in patients with AS undergoing surgical AVR or transcatheter AVR. On the basis of existing literature, adequately powered randomized trials are needed to evaluate the role of RAS inhibition in patients with AS.

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.

Age, Sex, and Valve Phenotype Differences in Fibro-Calcific Remodeling of Calcified Aortic Valve

Background

In calcific aortic valve disease on tricuspid aortic valves (TAVs), men have higher aortic valve calcification and less fibrosis than women. However, little is known in bicuspid aortic valves (BAV). We thus aimed to investigate the impact of age, sex, and valve phenotype (TAVs versus BAVs) on fibro‐calcific remodeling in calcific aortic valve disease.

Methods and Results

We included 2 cohorts: 411 patients who underwent multidetector computed tomography (37% women) for aortic valve calcification density assessment and 138 explanted aortic valves (histological cohort; 50% women). The cohorts were divided in younger (<60 years old) or older patients with BAV (≥60 years old), and TAV patients. In each group, women and men were matched. Women presented less aortic valve calcification density than men in each group of the multidetector computed tomography cohort (all P≤0.01). Moreover, in women, younger patients with BAV had the lowest aortic valve calcification density (both P=0.02). In multivariate analysis, aortic valve calcification density correlated with age (β estimate±standard error: 6.5±1.8; P=0.0004) and male sex (109.2±18.4; P<0.0001), and there was a trend with TAVs (41.5±23.0; P=0.07). Women presented a higher collagen content than men (77.8±10.8 versus 69.9±12.9%; P<0.001) in the entire cohort. In women, younger patients with BAV had denser connective tissue than TAV and older patients with BAV (both P≤0.05), while no difference was observed between men.

Conclusions

In calcific aortic valve disease, women had less calcification and more fibrotic remodeling than men, regardless of the phenotype of the valve or age of the patient. Moreover, younger women with BAVs had less valve calcification. Thus, mineralization/fibrosis of the aortic valve is likely to have sex/age‐specific mechanisms and be influenced by the valve morphology.

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.

Urea level is an independent predictor of mortality in patients with severe aortic valve stenosis

Introduction

Severe aortic stenosis (AS) is the most common valvular heart disease in the western world. Various factors are related to severe AS prognosis, including chronic kidney disease. The aim of this study was to evaluate the prognostic value of urea level in patients with severe AS.

Methods

We prospectively enrolled 142 patients (79.1±9.4 years, 88 women) with severe AS (mean valve area 0.67± 0.17 cm²). Clinical assessment, blood tests and echocardiography were performed at enrollment and follow up. The patient population was divided into low and high urea level groups, according to the median urea level at enrollment (72 patients, mean urea 35.5±6.2 mg/dL and 70 patients, mean urea 61.1±17.8 mg/dL, respectively). Hundred and twelve patients (79%) underwent aortic valve intervention. The primary endpoint was all-cause and cardiovascular mortality.

Outcomes

During follow-up of 37±19.5 months, 56 (37.1%) patients died, 39 due to cardiovascular causes. In univariate analysis, age, urea level, creatinine, New York Heart Association (NYHA) class and aortic valve intervention were associated with all-cause mortality. However, in multivariate analysis only aortic valve intervention and blood urea were independent predictors of all-cause mortality (HR 0.494; 95% CI 0.226–0.918, P = 0.026 and HR 1.015; 95% CI 1.003–1.029, P = 0.046 respectively). Urea level, NYHA class and age were also significant predictors of cardiovascular mortality. Whereas, in multivariate analysis, only urea level predicted cardiovascular mortality in these patients (HR 1.017; CI 1.003–1.031 P = 0.019).

Conclusions

Blood urea, a generally readily available and routinely determined marker of renal function, is an independent prognostic factor in patients with severe AS.

Durability of transcatheter aortic valve implantation: A translational review

Until recently, transcatheter aortic valve implantation was restricted to high-risk and inoperable patients. The updated 2017 European Society of Cardiology Guidelines has widened the indication to include intermediate-risk patients, based on two recently published trials (PARTNER 2 and SURTAVI). Moreover, two other recent trials (PARTNER 3 and EVOLUT LOW RISK) have demonstrated similar results with transcatheter aortic valve implantation in low-risk patients. Thus, extension of transcatheter aortic valve implantation to younger patients, who are currently treated by surgical aortic valve replacement, raises the crucial question of bioprosthesis durability. In this translational review, we propose to produce a state-of-the-art overview of the durability of transcatheter aortic valve implantation by integrating knowledge of the basic science of bioprosthesis degeneration (pathophysiology and biomarkers). After summarising the new definition of structural valve deterioration, we will present what is known about the pathophysiology of aortic stenosis and bioprosthesis degeneration. Next, we will consider how to identify a population at risk of early degeneration, and how basic science with the help of biomarkers could identify and predict structural valve deterioration. Finally, we will present data on the differences in durability of transcatheter aortic valve implantation compared with surgical aortic valve replacement.

[The renin-angiotensin-aldosterone system as a potential target for therapy in patients with calcific aortic stenosis: a literature review]

Calcific aortic valve stenosis (CAVS) is a serious socio-economic problem in developed countries because this disease is the most common indication for aortic valve replacement. Currently, there are no methods for non-invasive treatment of CAVS. Nevertheless, it is assumed that effective drug therapy for CAVS can be developed on the basis of modulators of the renin-angiotensin-aldosterone system (RAAS), which is involved in the pathogenesis of this disease. The purpose of this paper is to compile and analyze current information on the role of RAAS in the CAVS pathophysiology. Recent data on the effectiveness of RAAS inhibition are reviewed.

Development of calcific aortic valve disease: Do we know enough for new clinical trials?

Calcific aortic valve disease (CAVD), previously thought to represent a passive degeneration of the valvular extracellular matrix (VECM), is now regarded as an intricate multistage disorder with sequential yet intertangled and interacting underlying processes. Endothelial dysfunction and injury, initiated by disturbed blood flow and metabolic disorders, lead to the deposition of low-density lipoprotein cholesterol in the VECM further provoking macrophage infiltration, oxidative stress, and release of pro-inflammatory cytokines. Such changes in the valvular homeostasis induce differentiation of normally quiescent valvular interstitial cells (VICs) into synthetically active myofibroblasts producing excessive quantities of the VECM and proteins responsible for its remodeling. As a result of constantly ongoing degradation and re-deposition, VECM becomes disorganised and rigid, additionally potentiating myofibroblastic differentiation of VICs and worsening adaptation of the valve to the blood flow. Moreover, disrupted and excessively vascularised VECM is susceptible to the dystrophic calcification caused by calcium and phosphate precipitating on damaged collagen fibers and concurrently accompanied by osteogenic differentiation of VICs. Being combined, passive calcification and biomineralisation synergistically induce ossification of the aortic valve ultimately resulting in its mechanical incompetence requiring surgical replacement. Unfortunately, multiple attempts have failed to find an efficient conservative treatment of CAVD; however, therapeutic regimens and clinical settings have also been far from the optimal. In this review, we focused on interactions and transitions between aforementioned mechanisms demarcating ascending stages of CAVD, suggesting a predisposing condition (bicuspid aortic valve) and drug combination (lipid-lowering drugs combined with angiotensin II antagonists and cytokine inhibitors) for the further testing in both preclinical and clinical trials.

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.

Risk factors for valvular calcification

PURPOSE OF REVIEW

Recent literature is examined to identify established and emerging risk factors for valvular calcification, specifically calcific aortic valve disease and mitral annular calcification.

RECENT FINDINGS

Strong evidence implicates older age, male sex, cigarette smoking, elevated blood pressure, dyslipidaemia, adiposity, and mineral metabolism as risk factors for calcific aortic valve disease. Emerging evidence suggests family history and lipoprotein(a) are additional risk factors. Recently, large-scale genome-wide analyses have identified robust associations for LPA, PALMD, and TEX41 with aortic stenosis. Factors predisposing to mitral annular calcification are less well characterized. Older age, cigarette smoking, increased BMI, kidney dysfunction, and elevated triglycerides are associated with greater risk of mitral annular calcification, but conflicting evidence exists for sex and C-reactive protein.

SUMMARY

Established and emerging risk factors for calcific aortic valve disease, including some that overlap with atherosclerosis, may represent targets for pharmacological intervention. Mitral annular calcification is comparatively less well understood though some atherosclerosis risk factors do appear to increase risk.

The Role of Imaging in Measuring Disease Progression and Assessing Novel Therapies in Aortic Stenosis

Aortic stenosis represents a growing health care burden in high-income countries. Currently, the only definitive treatment is surgical or transcatheter valve intervention at the end stages of disease. As the understanding of the underlying pathophysiology evolves, many promising therapies are being investigated. These seek to both slow disease progression in the valve and delay the transition from hypertrophy to heart failure in the myocardium, with the ultimate aim of avoiding the need for valve replacement in the elderly patients afflicted by this condition. Noninvasive imaging has played a pivotal role in enhancing our understanding of the complex pathophysiology underlying aortic stenosis, as well as disease progression in both the valve and myocardium. In this review, the authors discuss the means by which contemporary imaging may be used to assess disease progression and how these approaches may be utilized, both in clinical practice and research trials exploring the clinical efficacy of novel therapies.

The Genetic Regulation of Aortic Valve Development and Calcific Disease

Heart valves are dynamic, highly organized structures required for unidirectional blood flow through the heart. Over an average lifetime, the valve leaflets or cusps open and close over a billion times, however in over 5 million Americans, leaflet function fails due to biomechanical insufficiency in response to wear-and-tear or pathological stimulus. Calcific aortic valve disease (CAVD) is the most common valve pathology and leads to stiffening of the cusp and narrowing of the aortic orifice leading to stenosis and insufficiency. At the cellular level, CAVD is characterized by valve endothelial cell dysfunction and osteoblast-like differentiation of valve interstitial cells. These processes are associated with dysregulation of several molecular pathways important for valve development including Notch, Sox9, Tgfβ, Bmp, Wnt, as well as additional epigenetic regulators. In this review, we discuss the multifactorial mechanisms that contribute to CAVD pathogenesis and the potential of targeting these for the development of novel, alternative therapeutics beyond surgical intervention.

Comparison of Lipoprotein(a)-Levels in Patients ≥70 Years of Age With Versus Without Aortic Valve Stenosis

Although lipoprotein(a) (Lp[a]) is linked with aortic valve calcification and clinical aortic valve stenosis (AVS) in middle-aged cohorts, patients aged ≥70 years represent a majority of patients with AVS, in which mechanisms leading to AVS may differ. We sought to determine whether Lp(a) distinguishes patients ≥70 years with and without AVS. We matched 484 patients ≥70 years with AVS, scheduled for transcatheter aortic valve implantation with 484 patients without AVS by age group and gender. Lp(a) levels were compared in patients with and without AVS and stratified by presence and absence of clinical coronary artery disease (CAD) manifestation. A total of 968 patients (mean age 80 ± 5 years, 48% women) were included. When comparing patients with and without AVS, no difference in Lp(a) was observed (AVS: 17 [8; 56] mg/dl, no AVS: 18.5 [8.5; 57] mg/dl, p = 0.56). In contrast, patients with clinical CAD manifestation had higher Lp(a) levels than those without clinical CAD manifestation (coronary artery disease: 19 [9; 60] mg/dl, no coronary artery disease 15 [7; 44] mg/dl, p = 0.0006). In regression analysis, no significant association of Lp(a) with AVS was observed in unadjusted (OR [95% CI]: 0.98 [0.91 to 1.06], p = 0.59) and risk factor-adjusted models (0.98 [0.90 to 1.06], p = 0.57). However, Lp(a) was independently associated with clinical CAD manifestation (unadjusted: 1.14 [1.04 to 1.24], p = 0.003, risk factor adjusted: 1.17 [1.07 to 1.27], p = 0.0006). In conclusion, in a large cohort of patients ≥70 years, Lp(a) was associated with clinical CAD manifesation, but not with AVS. Our results suggest that in patients over 70 years, the development of AVS is not influenced by Lp(a).

[The Old-Age Heart]

The Old-Age Heart Abstract. Knowledge of cardiovascular changes in old age and their therapeutic options is important. Old age can lead to hypertrophy of the left ventricle, diastolic dysfunction, heart valve changes and pulmonary hypertension. Patients often develop arterial hypertension. Valvular changes are common in people over 100 years of age (aortic stenosis and mitral insufficiency). The risk of coronary heart disease is 35 % for men and 24 % for women. In old age, sinus node dysfunction and atrial fibrillation are common. 25 % of all strokes are cardiac embolisms in atrial fibrillation. Cardiac interventions in the elderly are increasingly frequent and include coronary catheter revascularization or valve interventions (percutaneous aortic valve replacement or MitraClip). Optimal therapy in old age includes not only cardiovascular interventions also include drugs and a lifestyle modification and mainly serves to improve the quality of life.

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.

Relation Between Renin-Angiotensin System Blockers and Survival Following Isolated Aortic Valve Replacement for Aortic Stenosis

Renin-angiotensin system blockers (RASb) improve cardiac remodeling, but their clinical utility after surgical aortic valve replacement (SAVR) for aortic stenosis (AS) is unclear. We aimed to assess the impact of RASb on short- and long-term survival following isolated SAVR for severe AS. From January 2005 to January 2014, 508 consecutive patients had isolated SAVR for severe AS. Patients with RASb (n = 286; 53%) were more often female (p = 0.039), hypertensive (p < 0.0001), and diabetic (p = 0.004), with higher body mass index (p < 0.0001) and EuroSCORE II (p = 0.025), and lower mean aortic pressure gradient (p = 0.011). The 30-day mortality was similar in both groups (RASb: 3% vs no RASb: 5.8%, p = 0.13), but lower under angiotensin receptor blockers (ARB) than angiotensin-converting enzyme inhibitors (ACEi; 0.7% vs 5.6%, p = 0.017). Patients under RASb had a better 8-year survival than those without RASb (83 ± 3% vs 52 ± 5%, p < 0.0001), confirmed in a propensity score-matched pairs analysis (82 ± 4% vs 50 ± 7%, p < 0.0001). Regarding different types of RASb, patients under ARB had lower mortality than those under ACEi (87 ± 3% vs 79 ± 4%, p = 0.028). In multivariate analysis, the use of RASb was associated with improved survival (hazard ratio = 0.31, 95% confidence interval 0.20 to 0.47, p < 0.0001), with lower mortality under ARB than under ACEi (hazard ratio = 0.39, 95% confidence interval 0.18 to 0.85, p = 0.018). In this observational study, the use of RASb was associated with improved long-term outcome after isolated SAVR for severe AS. A randomized clinical trial is mandatory.

Effect of Losartan on Mitral Valve Changes After Myocardial Infarction

BACKGROUND

After myocardial infarction (MI), mitral valve (MV) tethering stimulates adaptive leaflet growth, but counterproductive leaflet thickening and fibrosis augment mitral regurgitation (MR), doubling heart failure and mortality. MV fibrosis post-MI is associated with excessive endothelial-to-mesenchymal transition (EMT), driven by transforming growth factor (TGF)-β overexpression. In vitro, losartan-mediated TGF-β inhibition reduces EMT of MV endothelial cells.

OBJECTIVES

This study tested the hypothesis that profibrotic MV changes post-MI are therapeutically accessible, specifically by losartan-mediated TGF-β inhibition.

METHODS

The study assessed 17 sheep, including 6 sham-operated control animals and 11 with apical MI and papillary muscle retraction short of producing MR; 6 of the 11 were treated with daily losartan, and 5 were untreated, with flexible epicardial mesh comparably limiting left ventricular (LV) remodeling. LV volumes, tethering, and MV area were quantified by using three-dimensional echocardiography at baseline and at 60 ± 6 days, and excised leaflets were analyzed by histopathology and flow cytometry.

RESULTS

Post-MI LV dilation and tethering were comparable in the losartan-treated and untreated LV constraint sheep. Telemetered sensors (n = 6) showed no significant losartan-induced changes in arterial pressure. Losartan strongly reduced leaflet thickness (0.9 ± 0.2 mm vs. 1.6 ± 0.2 mm; p < 0.05; 0.4 ± 0.1 mm sham animals), TGF-β, and downstream phosphorylated extracellular-signal-regulated kinase and EMT (27.2 ± 12.0% vs. 51.6 ± 11.7% α-smooth muscle actin-positive endothelial cells, p < 0.05; 7.2 ± 3.5% sham animals), cellular proliferation, collagen deposition, endothelial cell activation (vascular cell adhesion molecule-1 expression), neovascularization, and cells positive for cluster of differentiation (CD) 45, a hematopoietic marker associated with post-MI valve fibrosis. Leaflet area increased comparably (17%) in constrained and losartan-treated sheep.

CONCLUSIONS

Profibrotic changes of tethered MV leaflets post-MI can be modulated by losartan without eliminating adaptive growth. Understanding the cellular and molecular mechanisms could provide new opportunities to reduce ischemic MR.