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

Associations between central and brachial blood pressure in patients with hypertension and aortovascular disease: Implications for clinical practice

Central blood pressure (CBP) measurements, compared to brachial blood pressure (bBP), offer a superior predictive accuracy for aortovascular disease outcomes. This emphasises the distinctiveness of central hemodynamic metrics such as CBP, measuring the pressure directly exerted from the cardiac muscle to the major arteries, and provides a more direct assessment of cardiovascular workload than bBP, which measures the pressure against peripheral artery walls. This review synthesises findings evaluating the correlation between CBP and key aortovascular disease markers. Thoracic aortic aneurysm (TAA) growth is a crucial aspect of aortovascular assessment. CBP more accurately correlates with arterial stiffness (AS), the growth of TAA, and cardiovascular diseases, offering a more dependable prediction of aortovascular diseases, adverse cardiovascular events (CVE) and organ damage compared to bBP. The incorporation of CBP into routine clinical practice could enhance aortovascular assessments and therapeutic strategies when compared to bBP, particularly through a deeper understanding of aortic wave dynamics, which could fundamentally alter aortovascular diagnostics and treatment. In conclusion, integrating CBP into aortovascular and cardiovascular risk management is encouraged. Further research is necessary to substantiate these aspects and explore the operative implications of CBP in clinical settings.

Aortic valve neocuspidization and bioprosthetic valves: Evaluating turbulence haemodynamics

Aortic valve disease is often treated with bioprosthetic valves. An alternative treatment is aortic valve neocuspidization which is a relatively new reparative procedure whereby the three aortic cusps are replaced with patient pericardium or bovine tissues. Recent research indicates that aortic blood flow is disturbed, and turbulence effects have yet to be evaluated in either bioprosthetic or aortic valve neocuspidization valve types in patient-specific settings. The aim of this study is to better understand turbulence production in the aorta and evaluate its effects on laminar and turbulent wall shear stress. Four patients with aortic valve disease were treated with either bioprosthetic valves (n=2) or aortic valve neocuspidization valvular repair (n=2). Aortic geometries were segmented from magnetic resonance images (MRI), and 4D flow MRI was used to derive physiological inlet and outlet boundary conditions. Pulsatile large-eddy simulations were performed to capture the full range of laminar, transitional and turbulence characteristics in the aorta. Turbulence was produced in all aortas with highest levels occurring during systolic deceleration. In the ascending aorta, turbulence production is attributed to a combination of valvular skew, valvular eccentricity, and ascending aortic dilation. In the proximal descending thoracic aorta, turbulence production is dependent on the type of arch-descending aorta connection (e.g., a narrowing or sharp bend) which induces flow separation. Laminar and turbulent wall shear stresses are of similar magnitude throughout late systolic deceleration and diastole, although turbulent wall shear stress magnitudes exceed laminar wall shear stresses between 27.3% and 61.1% of the cardiac cycle. This emphasises the significance of including turbulent wall shear stress to improve our comprehension of progressive arterial wall diseases. The findings of this study recommend that aortic valve treatments should prioritise minimising valvular eccentricity and skew in order to mitigate turbulence generation.

Effects of intensive blood pressure control on left ventricular hypertrophy in aortic valve disease

BACKGROUND

Hypertension adds to the pressure overload on the left ventricle (LV) in combination with aortic valve (AV) disease, but the optimal blood pressure (BP) targets for patients with AV disease remain unclear. We tried to investigate whether intensive BP control reduces LV hypertrophy in asymptomatic patients with aortic stenosis (AS) or aortic regurgitation (AR).

METHODS

A total of 128 hypertensive patients with mild to moderate AS (n = 93) or AR (n = 35) were randomly assigned to intensive therapy, targeting a systolic BP <130 mm Hg, or standard therapy, targeting a systolic BP <140 mm Hg. The primary end point was the change in LV mass from baseline to the 24-month follow-up. Secondary end points included changes in severity of AV disease, LV volumes, ejection fraction and global longitudinal strain (GLS).

RESULTS

The treatment groups were generally well balanced regarding the baseline characteristics. The mean (±SD) age of the patients was 68 ± 8 years and 48% were men. The mean BP was 145 ± 12/81 ± 10 mm Hg at baseline. Medication at baseline was similar between the 2 groups. The 2 treatment strategies resulted in a rapid and sustained difference in systolic BP (P < .05). At 24-month, the mean systolic BP was 129 ± 12 mm Hg in the intensive therapy group and 135 ± 14 mm Hg in the standard therapy group. No patient died or underwent AV surgery during follow-up in either of the groups. LV mass was changed from 189.5 ± 41.3 to 185.6 ± 41.5 g in the intensive therapy group (P = .19) and from 183.8 ± 38.3 to 194.0 ± 46.4 g in the standard therapy group (P < .01). The primary end point of change in LV mass was significantly different between the intensive therapy and the standard therapy group (-3.9 ± 20.2 g vs 10.3 ± 20.4 g; P = .0007). The increase in LV mass index was also significantly greater in the standard therapy group (P = .01). No significant differences in secondary end points (changes in severity of AV disease, LV volumes, ejection fraction and GLS) were observed between the treatment groups.

CONCLUSIONS

Among hypertensive patients with AV disease, intensive hypertensive therapy resulted in a significant reduction in LV hypertrophy, although progression of AV disease was similar between the treatment groups.

CLINICAL TRIAL REGISTRATION

http://ClinicalTrials.gov (Number NCT03666351).

Aortic stenosis: a review on acquired pathogenesis and ominous combination with diabetes mellitus

BACKGROUND

Aortic stenosis (AS) is a progressive disease, with no pharmacological treatment. The prevalence of diabetes mellitus (DM) among AS patients is higher than in the general population. DM significantly increases the risk of AS development and progression from mild to severe. The interplay between AS and DM's mechanism is not entirely known yet.

MAIN BODY

The increased accumulation of advanced glycation end products (AGEs) was linked to increased valvular oxidative stress, inflammation, expression of coagulation factors, and signs of calcification, according to an analysis of aortic stenotic valves. It is interesting to note that in diabetic AS patients, valvular inflammation did not correlate with serum glucose levels but rather only with long-term glycemic management markers like glycated haemoglobin and fructosamine. Transcatheter aortic valve replacement, which has been shown to be safer than surgical aortic valve replacement, is advantageous for AS patients who also have concurrent diabetes. Additionally, novel anti-diabetic medications have been proposed to lower the risk of AS development in DM patients, including sodium-glucose cotransporter-2 inhibitors and glucagon-like peptide-1 receptor agonist that target reduction of AGEs-mediated oxidative stress.

CONCLUSIONS

There are little data on the effects of hyperglycemia on valvular calcification, but understanding the interactions between them is essential to develop a successful treatment strategy to stop or at least slow the progression of AS in DM patients. There is a link among AS and DM and that DM negatively impacts the quality of life and longevity of AS patients. The sole successful treatment, despite ongoing efforts to find new therapeutic modalities, involves aortic valve replacement. More research is required to find methods that can slow the advancement of these conditions, enhancing the prognosis and course of people with AS and DM.

Clinical significance and prognostic value of ST segment depression on ECG during exercise treadmill test in asymptomatic patients with moderate or severe aortic stenosis

Objectives. In patients with asymptomatic moderate or severe aortic stenosis (AS), exercise testing is used for evaluating the need for aortic valve intervention. Expert opinions about the clinical significance and prognostic value of ST segment depression on electrocardiography (ECG) during exercise testing in AS is conflicting and there are no large studies exploring this issue. We aimed to explore the association of ST segment depression >5 mm during exercise treadmill test (ETT) with all-cause mortality, aortic valve replacement (AVR) or cardiac-related hospitalization. Design. We performed a retrospective analysis of prospectively collected data of a total of 315 patients (mean age 65 ± 12 years, 67% men) with asymptomatic moderate (n = 209; 66%) or severe (n = 106; 34%) AS. All patients underwent clinical evaluation, echocardiography and ETT. Results. During a mean follow-up of 34.9 ± 34.6 months, 29 (9%) patients died and 235 (74%) underwent AVR. The prevalence of ST segment depression (>5 mm) was 13% (n = 41) in the total study population and was comparable in patients with revealed symptoms (17.6%, n = 16) versus without revealed symptoms (11.3%, n = 25; p = .132). ST segment depression on ETT was strongly associated with aortic valve area. In univariate Cox regression analysis, ST segment depression was not associated with cardiac related hospitalizations (HR 1.65; 95% CI 0.89-3.10, p = .113), all-cause mortality (HR 1.37; 95% CI 0.47-3.98, p = .564) or AVR (HR 1.30; 95% CI 0.89-1.91, p = .170). Conclusion. In patients with moderate or severe AS, ST segment depression during ETT is non-specific, carries no prognostic risk and should be used with caution in the clinical interpretation of exercise test.

Acute Heart Failure in an Almost-Centenarian Patient With Symptomatic Severe Aortic Stenosis Treated With Ivabradine

We report the case of a 99-year-old woman with acute chest pain caused by myocardial ischemia due to severe aortic stenosis (AS) and severe anemia. Red blood cells were transfused; however, this increased the preload and worsened pulmonary congestion. Treatment with drugs and non-invasive positive pressure ventilation could not sufficiently improve the pulmonary congestion. Ivabradine was administered to control the resting heart rate, following which the pulmonary congestion significantly improved. Ivabradine is a promising drug for acute heart failure of patients with AS by improving cardiac output by prolonging the left ventricular diastolic filling time without a negative inotropic effect.

Systemic blood pressure in severe aortic stenosis: Haemodynamic correlates and long-term prognostic impact

AIMS

Blood pressure (BP) targets in patients with aortic stenosis (AS) are controversial. This study sought to describe the haemodynamic profile and the clinical outcome of severe AS patients with low versus high central meaarterial pressure (MAP).

METHODS AND RESULTS

Patients with severe AS (n = 477) underwent right and left heart catheterization prior to aortic valve replacement (AVR). The population was divided into MAP quartiles. The mean systolic BP, diastolic BP, and MAP in the entire population were 149 ± 25, 68 ± 11, and 98 ± 14 mmHg. Patients in the lowest MAP quartile had the lowest left ventricular ejection fraction (LVEF), systemic vascular resistance, and valvulo-arterial impedance, whereas there were no significant differences in mean right atrial pressure, mean pulmonary artery wedge pressure, pulmonary vascular resistance, and stroke volume index across MAP quartiles. However, left ventricular stroke work index (LVSWI) was lowest in patients in the lowest and highest in those in the highest MAP quartile. After a median (interquartile range) post-AVR follow-up of 3.7 (2.6-5.2) years, mortality was highest in patients in the lowest MAP quartile [hazard ratio 3.08 (95% confidence interval 1.21-7.83); P = 0.02 for lowest versus highest quartile]. In the multivariate analysis, lower MAP [hazard ratio 0.78 (95% confidence interval 0.62-0.99) per 10 mmHg increase; P = 0.04], higher mean right atrial pressure and lower LVEF were independent predictors of death.

CONCLUSIONS

In severe AS patients, lower MAP reflects lower systemic vascular resistance and valvulo-arterial impedance, which may help to preserve stroke volume and filling pressures despite reduced left ventricular performance, and lower MAP is a predictor of higher long-term post-AVR mortality.

Exercise Testing in Aortic Stenosis: Safety, Tolerability, Clinical Benefits and Prognostic Value

Background: Routine exercise testing in asymptomatic patients with valvular heart disease (VHD) better classifies the hemodynamic severity of valve stenosis or regurgitation, and describes the symptomatic status and functional capacity of the patient. This is crucial for planned surveillance and optimal timing of surgery, particularly for aortic stenosis (AS), because once symptoms occur, there is a sharp increase in the risk of sudden death unless valve intervention is performed. Purpose: To conduct a focused clinical review on the benefits of exercise testing in patients with AS. Methods: The electronic database PubMed was systematically searched for relevant retrospective and prospective cohort studies reporting on the safety, feasibility and tolerability of exercise testing in VHD, with a special focus on AS. Results and conclusions: In patients with significant AS, exercise testing is safe, feasible and reveals symptoms in a significant proportion of patients. In addition, serial testing has incremental prognostic value over a baseline test alone. Exercise testing in patients with AS is underused and should be performed routinely to refine the hemodynamic severity of AS.

Left atrial volume index predicts adverse events in asymptomatic moderate or severe aortic stenosis

OBJECTIVE

In aortic stenosis (AS), chronic pressure overload on left ventricle (LV) leads to LV hypertrophy, impaired relaxation, increased chamber stiffness, fibrosis and left atrial (LA) dilatation. An enlarged LA may be a marker of longstanding diastolic dysfunction (DD) and more advanced disease in AS. We aimed to assess the impact of LA volume index (LAVI) on events in patients with moderate or severe AS.

METHODS

A total of 324 patients (mean age 69 ± 13 years, 61% men) were included. LA volume was measured by biplane Simpson's method using apical four- and two-chamber views and indexed to body surface area. An increased LAVI was defined as > 34 ml/m² .

RESULTS

The mean EF was 64 ± 8%, LAVI 35 ± 14 ml/m² and flow rate 244 ± 70 ml/s. The number of total events was 275 (85%): 243 (75%) aortic valve replacement and 32 (10%) deaths. Mean follow-up 23.7 ± 23.8 months (median 15.2 months). An increased LAVI (45% [n = 145]) was associated with adverse events (HR 1.86; 95% CI 1.24-2.82, p = 0.003) independent of age, smoking, diabetes, atrial fibrillation, LV ejection fraction, LV mass, aortic valve area, and low flow rate (<200 ml/s). In the same multivariate model, when increased LAVI was replaced by E/e' ratio ≥14 cm, no association was found between E/e' ratio ≥14 cm and adverse events (HR 1.18; 95% CI .78-1.78, p = 0.430).

CONCLUSION

LAVI was an independent predictor of adverse events in patients with moderate or severe AS and preserved ejection fraction. Including LAVI in the risk assessment of AS patients may further improve risk stratification.

Diabetes Mellitus and Its Implications in Aortic Stenosis Patients

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

Ageing, hypertension and aortic valve stenosis - Understanding the series circuit using cardiac magnetic resonance and applanation tonometry

BACKGROUND

Aortic stenosis (AS) is no longer considered to be a disease of fixed left ventricular (LV) afterload, but rather, functions as a series circuit, with important contributions from both the valve and vasculature. Patients with AS are typically elderly, with hypertension and a markedly remodelled aorta. The arterial component is sizeable, and yet, quantifying this to-date has been difficult to determine. We compared measurement of aortic pressure, flow and global LV load using a cardiac magnetic resonance (CMR)/applanation tonometry (AT) technique to uncouple ventriculo-arterial (VA) interactions.

METHODS

20 healthy elderly patients and 20 with AS underwent a CMR/AT protocol. CMR provided LV volume and aortic flow simultaneously with AT pressure acquisition. Aortic pressure was derived by transformation of the AT waveform. Systemic vascular resistance (SVR) and global LV load were determined as the relationship of pressure to flow in the frequency domain. Values from both cohorts were compared.

RESULTS

AS patients were older (p ​< ​0.01) albeit with no significant difference in brachial or central aortic pressure. SVR (14228 vs 19906 ​dyne ​s.cm-3; p ​= ​0.02) and load (740 vs 946 ​dyne ​s.cm-3; p ​= ​0.02) were higher in patients with AS, whilst aortic peak flow velocity was lower (38 vs 58 ​cm/s; p ​< ​0.01).

CONCLUSIONS

Quantification of aortic pressure, flow velocity and global LV load using a simultaneous CMR/AT technique is able to demonstrate the progressive effects of hypertension and aortic stiffening with advanced age and valvular stenosis. This technique may help to better identify future patients at risk of VA coupling mismatch after correction of AS.

Echocardiographic assessment of aortic stenosis: a practical guideline from the British Society of Echocardiography

The guideline provides a practical step-by-step guide in order to facilitate high-quality echocardiographic studies of patients with aortic stenosis. In addition, it addresses commonly encountered yet challenging clinical scenarios and covers the use of advanced echocardiographic techniques, including TOE and Dobutamine stress echocardiography in the assessment of aortic stenosis.

The advantages, pitfalls and limitations of guideline-directed medical therapy in patients with valvular heart disease

Heart failure is an inevitable end-stage consequence of significant valvular heart disease (VHD) that is left untreated and increasingly encountered in an ageing society. Recent advances in transcatheter procedures and improved outcomes after valve surgery mean that intervention can (and should) be considered in all patients - even the elderly and those with multiple comorbidities - at earlier stages of the natural history of primary VHD, before the onset of irreversible left ventricular dysfunction (and frequently before the onset of symptoms). All patients with known VHD should be monitored carefully in the setting of a heart valve clinic and those who meet guideline criteria for surgical or transcatheter intervention referred for intervention without delay. High quality evidence for the use of medical therapy in VHD is limited and achieving target doses in an elderly and comorbid population frequently challenging. Furthermore, determining whether the valve or ventricle is the principal disease driver is crucial (although the distinction is not always binary, and often unclear). Guideline-directed medical therapy remains the mainstay of treatment for secondary mitral regurgitation - although up to 50% of patients may fail to respond and should be considered for cardiac resynchronization, transcatheter or surgical valve intervention. Early and definitive management strategies are essential and should be overseen by a specialist Heart Team that includes a Heart Failure specialist. In this article, we provide an evidence-based summary of approaches to the medical treatment of VHD and clinical guidance for the best management of patients in situations where high quality evidence is lacking.

The electrocardiogram: Still a useful marker for LV fibrosis in aortic stenosis

Left ventricular (LV) strain on the electrocardiogram (ECG) (down-sloping, convex ST-segment depression with asymmetric T-wave inversion in leads V5 and V6) reflects fibrosis as a result of subendocardial ischemia. It is associated with a significantly increased risk of cardiovascular events independent of the presence of LV hypertrophy on the echocardiogram or cardiac magnetic resonance (CMR) scan. Ongoing studies of early aortic valve replacement in asymptomatic patients with severe aortic stenosis are using ECG changes as a marker of possible fibrosis shown by midwall late gadolinium enhancement on CMR. However, until these studies report, it is still reasonable to respond to LV strain on the ECG by tightening control of systemic hypertension and consider intervention in cases where indications are otherwise in borderline.

Impact of transcatheter aortic valve implantation on left ventricular function recovery, mass regression and outcome in patients with aortic stenosis: protocol of the TAVI-NOR prospective study

INTRODUCTION

Transcatheter aortic valve implantation (TAVI) is a widely used treatment option as an alternative to surgical aortic valve replacement in patients with severe aortic stenosis (AS) at high or intermediate surgical risk. TAVI improves symptoms, induces reverse left ventricular (LV) remodelling and increases overall survival. However, a careful patient selection is essential to achieve better outcome. Evidence on LV functional recovery and LV mass regression after TAVI based on contemporary registry data is scarce. The impact of TAVI on the arterial vasculature is also less explored.

METHOD AND ANALYSES

This is a study of 600 consecutive patients with AS who underwent a TAVI at Haukeland University Hospital, Bergen, Norway. Demographics, clinical data, arterial haemodynamics and echocardiographic parameters were prospectively collected. In the present paper, we describe the design, major scientific objectives and echocardiography imaging protocol of the TAVI-NOR (TAVI in western NORway) study. The main objectives are: To explore the impact of TAVI on cardiac structure and function in patients with severe AS, identify the echocardiographic predictors of reverse LV remodelling, assess survival benefits according to baseline risk profile, evaluate long-term therapeutic success as reflected by reduction in valvular-arterial impedance and to investigate the impact of various types of blood pressure response immediately after TAVI on clinical outcome.

ETHICS AND DISSEMINATION

The study was approved by the Regional Committees for Medical and Health Research Ethics (REK vest, ref. number 33814) and the Institutional Data Protection Services. Patients' consent was waived. The study findings will be disseminated via peer-reviewed publications and presentation in national and international scientific meetings and conferences.

TRAIL REGISTRATION NUMBER

The study was registered in the international database: ClinicalTrials.gov, Identifier: NCT04417829.

Predicting psychological factors affecting regular physical activity in hypertensive patients: Application of health action process approach model

Aim

The aim of this study was to determine the factors affecting the behaviour of regular physical activity in patients with hypertension using the health action process approach (HAPA) model.

Design

This cross-sectional study was conducted on 176 hypertension patients, in Astaneh-e-Ashrafiyeh, Guilan, Iran, 2018-2019.

Methods

Data collection tools included demographic characteristics, medical history, the short form of International Physical Activity Questionnaire (IPAQ) and scales related to the HAPA model. The data were analysed using chi-square, independent t test, one-way ANOVA, Pearson's correlation coefficient and path analysis on AMOS, version 23.0.

Results

Action self-efficacy (β = 0.59), outcome expectancy (β = 0.20) and risk perception (β = 0.18) had a statistically significant effect on intention. Moreover, the path coefficient between intention (β = 0.35) and coping self-efficacy (β = 0.29) with physical activity was statistically significant. The results revealed that HAPA constructs were able to describe 45% of the variance in intention and 31% of the variance in physical activity behaviour.

Conclusion

The HAPA model is a useful framework for describing the factors affecting physical activity in hypertension patients.

The clinical significance of the incorporation of tissue Doppler imaging into low-dose Dobutamine stress echocardiography in patients with aortic stenosis prior to Transcatheter aortic valve implantation

Background

Low-dose dobutamine stress echocardiography (DSE) is indicated in patients with low flow (stroke volume index [SVi] < 35 ml/m²) low gradient (mean pressure gradient < 40 mmHg) and left ventricular ejection fraction (LVEF) < 50% aortic stenosis (AS) to assess LV contractile reserve (> 20% increase in SVi) and severity grade of AS. Severe AS is defined by a mean pressure gradient of 40 mmHg occurring at any time during the test when aortic valve area remains < 1.0 cm².

Case presentation

This case report highlights the utility of mitral annular systolic velocity (S′) by tissue Doppler imaging and peak LV outflow tract (LVOT) velocity as markers of LV intrinsic contractile function during DSE in a patient with low flow low gradient AS and reduced EF prior to transcatheter aortic valve implantation (TAVI).

Conclusions

Mitral annular S′ and peak LVOT velocities are reliable markers of LV intrinsic contractile function and should be incorporated into routine low-dose DSE.

Sex differences in aortic stenosis: from pathophysiology to treatment

Introduction: In aortic stenosis (AS), there are clear sex differences in clinical presentation, left ventricular (LV) response to pressure overload, and pathophysiology of valvular calcification. These differences may affect outcome following valve intervention.Area covered: This review aims to discuss sex differences in clinical presentation, pathophysiology of aortic valve calcification, LV remodeling in view of historic and recent echocardiographic and cardiac magnetic resonance imaging studies, and outcome after valve intervention. In addition, it will also provide some brief insights on the exercise physiology in women and men with AS.Expert commentary: Women at presentation are often older, have higher prevalence of hypertension and diastolic dysfunction, while men are younger, and more often have a bicuspid aortic valve and higher atherosclerotic disease burden. Men have more valve calcification than women for a given severity of AS and develop different patterns of LV remodeling and myocardial fibrosis. Although women tend to walk shorter on treadmill and achieve lower metabolic equivalents, they achieve similar peak heart rates and blood pressure, and the frequency of revealed symptoms during exercise test is comparable in both sexes. Men are more likely to undergo a surgical AVR with better outcome, while women have generally better outcome after TAVI.