The Impact of Hypertension and Hypertension-Related Left Ventricle Hypertrophy on Right Ventricle Function

Ethnicity differences in geometric remodelling and myocardial composition in hypertension unveiled by cardiovascular magnetic resonance

AIMS

Hypertensive patients of African ancestry (Afr-a) have higher incidences of heart failure and worse clinical outcomes than hypertensive patients of European ancestry (Eu-a), yet the underlying mechanisms remain misunderstood. This study investigated right (RV) and left (LV) ventricular remodelling alongside myocardial tissue derangements between Afr-a and Eu-a hypertensives.

METHODS AND RESULTS

63 Afr-a and 47 Eu-a hypertensives underwent multi-parametric cardiovascular magnetic resonance. Biventricular volumes, mass, function, mass/end-diastolic volume (M/V) ratios, T2 and pre-/post-contrast T1 relaxation times, synthetic extracellular volume, and myocardial fibrosis (MF) were measured. 3D shape modelling was implemented to delineate ventricular geometry. LV and RV mass (indexed to body-surface-area) and M/V ratio were significantly greater in Afr-a than Eu-a hypertensives (67.1 ± 21.7 vs. 58.3 ± 16.7 g/m2, 12.6 ± 3.48 vs. 10.7 ± 2.71 g/m2, 0.79 ± 0.21 vs. 0.70 ± 0.14 g/mL, and 0.16 ± 0.04 vs. 0.13 ± 0.03 g/mL, respectively; P < 0.03). Afr-a patients showed greater basal interventricular septum thickness than Eu-a patients, influencing LV hypertrophy and RV cavity changes. This biventricular remodelling was associated with prolonged T2 relaxation time (47.0 ± 2.2 vs. 45.7 ± 2.2 ms, P = 0.005) and higher prevalence (23% vs. 4%, P = 0.001) and extent of MF [2.3 (0.6-14.3) vs. 1.6 (0.9-2.5) % LV mass, P = 0.008] in Afr-a patients. Multivariable linear regression showed that modifiable cardiovascular risk factors and greater end-diastolic volume, but not ethnicity, were independently associated with greater LV mass.

CONCLUSION

Afr-a hypertensives had distinctive biventricular remodelling, including increased RV mass, septal thickening and myocardial tissue abnormalities compared with Eu-a hypertensives. From this study, modifiable cardiovascular risk factors and ventricular geometry, but not ethnicity, were independently associated with greater LV myocardial mass.

Impact of T2DM on right ventricular systolic dysfunction and interventricular interactions in patients with essential hypertension: evaluation using CMR tissue tracking

Background

Previous studies reported that there was right ventricular (RV) systolic dysfunction in patients with hypertension. The aim of this study was to evaluate the impact of type 2 diabetes mellitus (T2DM) on RV systolic dysfunction and interventricular interactions using cardiac magnetic resonance feature tracking (CMR-FT) in patients with essential hypertension.

Methods and methods

Eighty-five hypertensive patients without T2DM [HTN(T2DM −)], 58 patients with T2DM [HTN(T2DM +)] and 49 normal controls were included in this study. The biventricular global radial, circumferential and longitudinal peak strains (GRS, GCS, GLS, respectively) and RV regional strains at the basal-, mid- and apical-cavity, were calculated with CMR-FT and compared among controls and different patient groups. Backward stepwise multivariable linear regression analyses were used to determine the effects of T2DM and left ventricular (LV) strains on RV strains.

Results

The biventricular GLS and RV apical longitudinal strain deteriorated significantly from controls, through HTN(T2DM-), to HTN(T2DM +) groups. RV middle longitudinal strain in patient groups were significantly reduced, and LV GRS and GCS and RV basal longitudinal strain were decreased in HTN(T2DM +) but preserved in HTN(T2DM-) group. Multivariable regression analyses adjusted for covariates demonstrated that T2DM was independently associated with LV strains (LV GRS: β = − 4.278, p = 0.004, model R2 = 0.285; GCS: β = 1.498, p = 0.006, model R2 = 0.363; GLS: β = 1.133, p = 0.007, model R2 = 0.372) and RV GLS (β = 1.454, p = 0.003, model R2 = 0.142) in hypertension. When T2DM and LV GLS were included in the multiple regression analysis, both T2DM and LV GLS (β = 0.977 and 0.362, p = 0.039 and < 0.001, model R2 = 0.224) were independently associated with RV GLS.

Conclusions

T2DM exacerbates RV systolic dysfunction in patients with hypertension, which may be associated with superimposed LV dysfunction by coexisting T2DM and suggests adverse interventricular interactions.

Strain Imaging for the Early Detection of Cardiac Remodeling and Dysfunction in Primary Aldosteronism

Speckle tracking echocardiography is a novel technique to quantify cardiac function and deformation. It has been applied in a series of cardiovascular diseases for the evaluation of early cardiac impairment. We recently used this technique to investigate cardiac structure and function in patients with primary aldosteronism. Cardiac damage usually occurs earlier in patients with primary aldosteronism than those with primary hypertension, probably because aldosterone hypersecretion is more commonly observed in the former than the latter patients. In this article, we will review the imaging studies, especially with speckle tracking echocardiography, for the detection of early cardiac dysfunction in primary aldosteronism as a disease model.

Role of strain echocardiography in patients with hypertension

Hypertension is a well-recognized risk factor for the development of cardiovascular disease, and the early detection of cardiac changes from hypertension can allow reversing these. Hypertensive heart diseases (HHD) refer to the complex and diverse change of the cardiac structure and function secondary to hypertension. Although conventional echocardiography is the most common imaging modality in detecting HHD, it cannot detect subtle changes of cardiac structure in subclinical states. Because strain echocardiography is another echocardiographic modality can detect subclinical myocardial dysfunction by measuring intrinsic myocardial deformation, it became more and more popular in clinical and research fields. In this review article, we described the basic concept of strain echocardiography and summarized several clinical studies showing its clinical utilities in the detection of HHD.

Cardiac Remodeling According to the Nocturnal Fall of Blood Pressure in Hypertensive Subjects: The Whole Assessment of Cardiac Abnormalities in Non-Dipper Subjects with Arterial Hypertension (Wacanda) Study

Objective: Several epidemiological studies suggest that the preservation of the physiological circadian rhythm of blood pressure or its disruption affects the extent of the organ damage developed by the patient. If we classify the circadian rhythm of blood pressure into four nocturnal profiles, significant differences emerge in terms of organ damage burden and prognosis: reverse dippers have the worst prognosis while dippers and mild dippers fall into an intermediate risk range. The risk profile of extreme dippers is still debated, and the available data are very conflicting and inconclusive. Starting from this gap of knowledge, we aimed to evaluate, retrospectively, in a cohort of hypertensive subjects, the degree of cardiac involvement in relation to the different nocturnal blood pressure profiles. Methods: We retrospectively evaluated 900 patients with essential hypertension, of whom 510 met our study criteria. We graded the 510 patients in relation to the percentage of reduction in mean systolic blood pressure (SBP) at night-time compared with day-time, considering this as a continuous variable, and then compared the extreme quintiles with each other and with the middle quintile (considered as reference). Results: Patients with less (or no) reduction in nocturnal SBP (reverse dipper) showed a higher level of organ damage and comorbidities. With regard to echocardiographic indexes, patients with maximum nocturnal pressure reduction (extreme dipper) showed a lower level of remodeling and/or impairment of E/e’ ratio, Right Atrium Area, Basal Right Ventricular Diameter, Inferior Vena Cava Average Diameter, and Tricuspidal Anular Plane Systolic Excursion compared also with hypertensive patients with a physiological nocturnal pressure reduction, even after correction for the main confounders. Conclusions: These data suggest that extreme dippers may constitute the subgroup of hypertensive patients with the lowest 24-h pressure load and, therefore, less cardiac remodeling.

Contemporary narrative review on left atrial strain mechanics in echocardiography: cardiomyopathy, valvular heart disease and beyond

Left atrial (LA) strain mechanics refer to the measurement of LA myocardial deformation expressed as a percentage, and have been gathering interest over the last decade with expanding research supporting their utility in multiple cardiovascular disorders. Measured through advanced dynamic imaging techniques which include tissue Doppler imaging (TDI) and two-dimensional (2D) speckle tracking echocardiography (STE), LA strain mechanics are affected by left ventricular diastolic dysfunction prior to the onset of functional and structural changes in the left ventricle (LV). There is a need for practising cardiologists to become more familiar with the clinical utility of LA strain mechanics. In this article, we begin by reviewing the physiologic function of the LA, using this as a basis for understanding LA strain mechanics. The focus of this review article is to provide a contemporary update on the utility of LA strain mechanics in a range of cardiovascular disorders, including atrial fibrillation (AF), hypertrophic cardiomyopathy (HCM), valvular pathologies, coronary artery disease (CAD) as well as systemic diseases, such as hypertension (HTN), obesity and diabetes mellitus (DM). This article also highlights the current limitations in more widespread clinical applications of LA strain mechanics, as well as outlining the future perspectives on the clinical applications of LA strain mechanics.

Pathophysiology of Hypertensive Heart Disease: Beyond Left Ventricular Hypertrophy

PURPOSE OF REVIEW

Given that the life expectancy and the burden of hypertension are projected to increase over the next decade, hypertensive heart disease (HHD) may be expected to play an even more central role in the pathophysiology of cardiovascular disease (CVD). A broader understanding of the features and underlying mechanisms that constitute HHD therefore is of paramount importance.

RECENT FINDINGS

HHD is a condition that arises as a result of elevated blood pressure and constitutes a key underlying mechanism for cardiovascular morbidity and mortality. Historically, studies investigating HHD have primarily focused on left ventricular (LV) hypertrophy (LVH), but it is increasingly apparent that HHD encompasses a range of target-organ damage beyond LVH, including other cardiovascular structural and functional adaptations that may occur separately or concomitantly. HHD is characterized by micro- and macroscopic myocardial alterations, structural phenotypic adaptations, and functional changes that include cardiac fibrosis, and the remodeling of the atria and ventricles and the arterial system. In this review, we summarize the structural and functional alterations in the cardiac and vascular system that constitute HHD and underscore their underlying pathophysiology.

Elevated 1-h post-load plasma glucose is associated with right ventricular morphofunctional parameters in hypertensive patients

PURPOSE

Emerging data demonstrate that type 2 diabetes mellitus (T2DM) is associated with right ventricular (RV) dysfunction. A cutoff point of 155 mg/dL for the 1-hour (h) post-load plasma glucose, during oral glucose tolerance test (OGTT), identifies patients with normal glucose tolerance (NGT) at high risk to develop T2DM and cardiovascular (CV) disease. We investigated if 1-h post-load glucose may affect RV geometry and function in a group of never-treated hypertensive individuals.

METHODS

We enrolled 446 Caucasian newly diagnosed hypertensive outpatients. All patients underwent an OGTT and a standard echocardiography. The tricuspid annular plane systolic excursion (TAPSE) and the RV fractional area change (RVFAC) were measured together with systolic pulmonary arterial pressure (s-PAP) and pulmonary vascular resistances (PVR). Insulin sensitivity was evaluated using the Matsuda index.

RESULTS

Among all partecipants, 296 had NGT, 100 impaired glucose tolerance (IGT), and 50 T2DM. Considering the cutoff point of 155 mg/dl for 1-h glucose, NGT subjects were stratified into two groups: NGT < 155 (n = 207), NGT ≥ 155 (n = 89). Subjects NGT ≥ 155 presented a worse metabolic and inflammatory profile than NGT < 155. RV functional parameters (TAPSE, RVFAC, TAPSE/s-PAP, and TAPSE/PVR) were significantly reduced in NGT ≥ 155 subjects compared with NGT < 155 patients. On the contrary, s-PAP and PVR were significantly higher. At multiple regression analysis, 1-h glucose was the strongest predictor of TAPSE in NGT ≥ 155, IGT, and T2DM.

CONCLUSIONS

The presence of RV impairment in hypertensive NGT ≥ 155 subjects further complicates their CV burden and it may, at least in part, justify the worse clinical outcome in this setting of patients.

Right ventricular dysfunction in arterial hypertension: still terra incognita?

The effects of systemic hypertension on left ventricular function have been well described, as has been the response of the resulting alterations to antihypertensive treatment. However, hypertension effects on the right ventricle (RV) have not been sufficiently investigated; only in recent years, with the development of new imaging modalities, has its importance become widely recognized. Indeed, evidence from clinical trials suggestive of RV functional and structural impairment early in the course of arterial hypertension continues to accumulate. Newer imaging techniques, especially speckle-tracking-derived myocardial deformation imaging, have provided new insights into the effect of systemic hypertension on this previously neglected cardiac chamber. Two- and three-dimensional echocardiography, along with cardiac magnetic resonance imaging, forms the cornerstone of RV structural and functional assessment. This article provides an overview of the effect of longstanding hypertension on RV structure and function, the respective underlying mechanisms, and the potential therapeutic implications. It summarizes the available options for RV structural and functional assessment, and evaluates the existing evidence with respect to RV alterations in hypertensive disease, aiming to assess the current limits of scientific knowledge about a heart chamber that has only recently become the focus of greater interest.

Right ventricular involvement in transthyretin amyloidosis

BACKGROUND

The extent of right ventricular (RV) involvement in transthyretin amyloidosis (ATTR) is unknown.

OBJECTIVES

This study sought to establish the degree of RV involvement in ATTR amyloidosis, and compare findings with RV involvement in hypertrophic cardiomyopathy (HCM).

METHODS

Forty-two patients with ATTR amyloidosis and echocardiographic evidence of cardiac amyloidosis (cardiac ATTR), 19 ATTR patients with normal left ventricular (LV) wall thickness (non-cardiac ATTR), 25 patients with diagnosed HCM and 30 healthy controls were included in this study. Echocardiographic measurements for conventional parameters, as well as RV global and segmental strain, were recorded.

RESULTS

When comparing RV structure and function between cardiac ATTR amyloidosis and HCM patients, only segmental strain differed between the two groups. In cardiac ATTR amyloidosis, we found an RV apex-to-base strain gradient with highest deformation in the apex. This pattern was reversed in patients with HCM.

CONCLUSIONS

RV involvement is common in cardiac ATTR patients. The present study also detected an RV apical sparing pattern in patients with ATTR cardiomyopathy, similar to what has previously been described for the left ventricle in these patients. This pattern was not seen in HCM patients. Further studies are needed to assess the clinical importance of these findings.

Right heart remodeling induced by arterial hypertension: Could strain assessment be helpful?

Left ventricular structural and functional changes in patients with arterial hypertension are well established. However, the influence of arterial hypertension on right ventricular (RV) remodeling is still being investigated. The introduction of strain analysis provided an insight into RV function and mechanics. Previous research has demonstrated the predictive value of RV longitudinal strain in patients with various cardiovascular conditions, such as pulmonary hypertension, heart failure, congenital heart diseases, and valvular disease. Nowadays, we are aware of the fact that conventional echocardiographic methods usually do not provide necessary information about RV dysfunction in patients with arterial hypertension, which is why the evaluation of new parameters that could detect RV subtle changes in hypertension is essential. The present review article is an overview of the main principles of RV deformation and a summary of the current knowledge and clinical significance of RV strain in patients with arterial hypertension.

Estrogen receptor beta signals to inhibition of cardiac fibrosis

Cardiac fibrosis evolves from the cardiac hypertrophic state. In this respect, estrogen and estrogen receptor beta (ERβ) inhibit the effects of cardiac hypertrophic peptides that also stimulate fibrosis. Here we determine details of the anti-fibrotic functions of ERβ. In acutely isolated rat cardiac fibroblasts. E2 or a specific ERβ agonist (βLGND2) blocked angiotensin II (AngII) signaling to fibrosis. This resulted from ERβ activating protein kinase A and AMP kinase, inhibiting both AngII de-phosphorylation of RhoA and the resulting stimulation of Rho kinase. Inhibition of Rho kinase from ERβ signaling resulted in marked decrease of TGFβ expression, connective tissue growth factor production and function, matrix metalloproteinases 2 and 9 expression and activity, and the conversion of fibroblasts to myofibroblasts. Production of collagens I and III were also significantly decreased. Several important aspects were corroborated in-vivo from βLGND2-treated mice that underwent AngII-induced cardiac hypertrophy. Thus, ERβ in cardiac fibroblasts prevents key aspects of cardiac fibrosis development.

Relationship between right ventricular remodeling and heart rate variability in arterial hypertension

OBJECTIVE

We aimed at evaluating right ventricular remodeling (structure, function, and mechanics) and heart rate variability (HRV), as well as their interaction, in untreated hypertensive patients.

METHOD

This cross-sectional study involved 55 untreated hypertensive patients and 40 patients with no risk factors, similar by sex and age. All the patients underwent a 24-h Holter monitoring and comprehensive two-dimensional and three-dimensional echocardiography assessment (2DE and 3DE).

RESULTS

All time and frequency domain HRV variables were reduced in the hypertensive patients. Right ventricular systolic and diastolic function, as well as right ventricular longitudinal strain, was significantly impaired in the hypertensive patients. Parameters that indicate comprehensive right ventricular remodeling (right ventricular wall thickness, tricuspid E/e' ratio, 2DE right ventricular longitudinal strain, and 3D right ventricular ejection fraction) correlated with the parameters of cardiac sympathovagal balance (SD of all normal RR intervals, root mean square of the difference between the coupling intervals of adjacent RR intervals, 24-h low-frequency domain, 24-h high-frequency domain, and 24-h total power). Of note, right ventricular diastolic function, right ventricular longitudinal function, and 3DE right ventricular ejection fraction were associated with cardiac autonomic nervous function, independently of age, BMI, blood pressure, and left ventricular hypertrophy.

CONCLUSIONS

Right ventricular structure, systolic and diastolic function, as well as right ventricular longitudinal deformation, are significantly impaired in untreated hypertensive patients. HRV variables are also decreased in hypertensive population. 2DE and 3DE parameters resembling right ventricular remodeling are independently associated with cardiac autonomic nervous system markers in the whole study population.

The proposed role of plasma NT pro-brain natriuretic peptide in assessing cardiac remodelling in hypertensive African subjects

AIM

Although plasma NT-proBNP differentiates hypertension (HT) with or without left ventricular hypertrophy (LVH) from hypertensive heart failure (HHF), most of the published data are based on studies in Western populations. Also, most previous studies did not consider left ventricular (LV) diastolic function and right ventricular (RV) function. We therefore examined the relation between NT-proBNP on LV and RV remodelling in an African hypertensive cohort.

METHODS

Subjects were subdivided into three groups after echocardiography: hypertensives without LVH (HT) (n = 83); hypertensives with LVH (HT + LVH) (n = 50); and those with hypertensive heart failure (HHF) (n = 77).

RESULTS

Subjects with HHF had significantly higher NT-proBNP levels compared to the HT + LVH group (p < 0.0002). NT-proBNP correlated positively with right atrial area, an indirect measure of RV function.

CONCLUSIONS

NT-proBNP is proposed as a useful biomarker in differentiating hypertension with or without LVH from hypertensive heart failure in black hypertensive subjects.

Echocardiographic Assessment of the Right Ventricle, from the Conventional Approach to Speckle Tracking and Three-Dimensional Imaging, and Insights into the "Right Way" to Explore the Forgotten Chamber

BACKGROUND

The right ventricle (RV) has an essential function in cardiovascular physiology and pathology. Currently, it is gaining an increasing interest given its recognized role in many cardiovascular conditions. However, echocardiographic assessment of the RV in daily practice is frequently based on qualitative estimation, and it has been regarded as a neglected chamber.

OBJECTIVE

We sought to review and discuss the appropriate approach and latest methods of assessment of the RV by echocardiography.

METHODS

A MEDLINE/Pubmed search was performed, and 55 relevant articles were selected; articles addressing right ventricular assessment by echocardiography, along with the latest recommendations, have been reviewed and discussed.

RESULTS

A RV diameter >42 mm at the base and >35 mm at the mid-cavitary level indicates right ventricular dilatation; a longitudinal myocardial velocity (S') <9.5 mm/s, a tricuspid annular plane systolic excursion <17 mm, and a fractional area change <35% are indices of right ventricular systolic dysfunction. A right ventricular ejection fraction of >45% and an absolute value of global longitudinal strain of >21% reflect normal systolic function. The significance of dp/dt, the right myocardial performance index and isovolumic myocardial acceleration, is also discussed along with the parameters of right ventricular diastolic function. The use of novel echocardiographic approaches, such as three-dimensional echo and speckle tracking imaging, allows practitioners to overcome the challenges encountered with conventional echocardiography.

CONCLUSION

Accurate assessment of the RV by echocardiography yields early detection of cardiac diseases, enhances risk stratification, and allows timely initiation of appropriate therapy.

Comparison of subclinical left and right ventricular systolic dysfunction in non-dipper and dipper hypertensives: impact of isovolumic acceleration

Abstract Objectives: To evaluate subclinical left ventricular and right ventricular systolic impairment in dipper and non-dipper hypertensives by using isovolumic acceleration.

METHODS

About 45 normotensive healthy volunteers (20 men, mean age 43 ± 9 years), 45 dipper (27 men, mean age 45 ± 9 years) and 45 non-dipper (25 men, 47 ± 7 years) hypertensives were enrolled. Isovolumic acceleration was measured by dividing the peak myocardial isovolumic contraction velocity by isovolumic acceleration time.

RESULTS

Non-dippers indicated lower left ventricular (2.2 ± 0.4 m/s(2) versus 2.8 ± 1.0 m/s(2), p < 0.01) and right ventricular isovolumic acceleration values (2.8 ± 0.8 m/s(2) versus 3.5 ± 1.0 m/s(2), p = 0.012) compared with dippers. Left ventricular mass index (p = 0.001), interventricular septal thickness (p = 0.002) and myocardial performance index (p < 0.001) were negatively correlated with left ventricular isovolumic acceleration. Left ventricular septal thickness (p = 0.002), mass index (p = 0.001) and right ventricular myocardial performance index (p < 0.001) were negatively correlated with right ventricular isovolumic acceleration.

CONCLUSION

The present study demonstrates that non-dipper hypertensives have increased left and right ventricular subclinical systolic dysfunction compared with dippers. Isovolumic acceleration is the only echocardiographic parameter in predicting this subtle impairment.

Right ventricular hypertrophy in systemic hypertension: an updated review of clinical studies

AIM

Experimental and clinical evidence supports the view that right ventricular hypertrophy (RVH) may parallel left ventricular hypertrophy in systemic hypertension; a comprehensive analysis of this issue, however, is lacking. Thus, we analyzed the literature in order to provide an updated information on the right ventricular structural changes associated to systemic hypertension.

DESIGN

A literature search using the key words 'right ventricle' 'right ventricular hypertrophy', 'biventricular hypertrophy' 'right and left ventricular hypertrophy'. 'hypertension', 'echocardiography' was performed in order to identify relevant articles. Full articles published in English language in the last three decades reporting studies in adult hypertensive individuals were considered.

RESULTS

A total of 13 studies, including 1290 untreated (45%) and treated hypertensive patients and 259 normotensive controls, were considered. Overall, in hypertensive individuals right ventricular wall was thicker than in normotensive counterparts (standardized difference 1.3 mm, P < 0.001). RVH prevalence consistently varied among studies (17.0-80.0%) with an average of 28.6% in the pooled population. This was also the case for LVH prevalence rates (9.0-100%) with an average value of 30.6%.

CONCLUSION

Clinical studies consistently indicate that RVH is a common cardiac phenotype in systemic hypertension. As this finding is based on a limited number of cross-sectional studies including small population samples, further investigations are needed to determine the clinical utility and prognostic value of this phenotype in clinical practice.

Carotid atherosclerosis and right ventricular diastolic dysfunction in a sample of hypertensive Nigerian patients

AIM

To determine the association of carotid atherosclerosis and right ventricular diastolic dysfunction (DD) among treated hypertensive Nigerian patients.

METHODS

This was a single center cross-sectional study performed at the Cardiology Clinic of LAUTECH Teaching Hospital, Ogbomoso, Nigeria between January and December 2012. The study included 122 hypertensive Nigerians (mean age, 57.3±14.7 years, 36.9% women). Patients' clinical, demographic, and echocardiographic parameters were obtained. Diastolic dysfunction was assessed with the trans-tricuspid Doppler flow.

RESULTS

Patients with DD were significantly older than those with normal diastolic function. Mean and maximum carotid intima media thickness measurements were significantly higher among patients with right ventricular DD than in those with normal diastolic function. Mean systolic blood pressure (148.3±31.9 vs 128.0±2.8 mm Hg, P=0.049) and interventricular septal thickness in diastole (12.8±2.3 vs 11.6±2.8 mm, P=0.048) were significantly higher and tricuspid annular pulmonary systolic excursion (33.6±4.9 vs 23.0±4.2 mm, P=0.035) was significantly lower in patients with right ventricular DD than in those with normal diastolic function. Carotid intima media thickness measurements were correlated with early trans-tricuspid Doppler flow and early transtricuspid diastolic flow/late right atrial transtricupsid diastolic flow ratio.

CONCLUSION

Right ventricular DD in hypertensive patients was significantly correlated with increased carotid atherosclerosis. Carotid intima media thickness measurements may therefore be a surrogate marker for DD in hypertensive subjects.

Metabolic syndrome and right ventricle: an updated review

The cluster of metabolic and hemodynamic abnormalities which characterize the metabolic syndrome (MS) is responsible for subclinical cardiac and extra-cardiac damage such as left ventricular hypertrophy, diastolic dysfunction, carotid atherosclerosis and microalbuminuria. The development of different non-invasive imaging methods enabled a detail investigation of right ventricular structure and function, and revealed that right ventricular remodeling followed changes in the left ventricular structure and function in patients with arterial hypertension, diabetes or obesity. Previous investigations also reported that the coexistence of two components of the MS induced more significant cardiac remodeling than the presence of only one MS risk-factor. The relationship between different components of the MS (increased blood pressure, abdominal obesity, increased fasting glucose level and dyslipidemia) and right ventricular remodeling could be explained by several hemodynamic and non-hemodynamic mechanisms. However, the association between right ventricular remodeling and the MS has not been sufficiently investigated so far. The aim of this article was to review recent articles focusing on the association between metabolic syndrome components and the metabolic syndrome itself with impairments in right ventricular structure and function assessed by different imaging techniques.

Circadian blood pressure pattern and right ventricular and right atrial mechanics: A two- and three-dimensional echocardiographic study

The purpose of this investigation was to evaluate right ventricular (RV) and right atrial (RA) function and mechanics in untreated hypertensive patients with different blood pressure (BP) patterns by using two-dimensional (2DE) speckle tracking analyses and three-dimensional echocardiography (3DE). This cross-sectional study included 174 recently diagnosed hypertensive patients. All patients underwent a 24-hour ambulatory BP monitoring and complete 2DE and 3DE examination, including 2DE speckle tracking analysis. Our results showed that 2DE RV global longitudinal strain was significantly lower in the non-dippers. Similar results were obtained for 2DE RV systolic and early diastolic strain rate. The RA longitudinal strain, as well as RA systolic and early diastolic strain rate, was decreased in non-dippers. Our results revealed that 3DE RV end-diastolic and end-systolic volumes were increased, whereas 3DE RV ejection fraction was reduced in non-dipper hypertensive patients. Similar results were obtained for RA volumes and RA ejection fraction estimated by 2DE. Independent predictors of 3DE RV ejection fraction, 2DE RV and RA global longitudinal strain were left ventricular mass index and RV wall thickness. An additional independent predictor of the RV longitudinal strain was 3DE RV ejection fraction, and for RA longitudinal strain, an additional independent predictor was tricuspid E/é ratio. Two-DE speckle tracking evaluation and 3DE examination revealed that the RV and RA function and mechanics were more deteriorated in the non-dipper patients than in dipper untreated hypertensive patients.

Cardiovascular modeling in pulmonary arterial hypertension: focus on mechanisms and treatment of right heart failure using the CircAdapt model

In recent years, increased understanding of cardiovascular system dynamics has led to the development of mathematical models of the heart and circulation. Models that enable realistic simulation of ventricular mechanics and interactions under a range of conditions have the potential to provide an ideal method with which to investigate the effects of pulmonary arterial hypertension and its treatment on cardiac mechanics and hemodynamics. Such mathematical models have the potential to contribute to a personalized, patient-specific treatment approach and allow more objective diagnostic decision-making, patient monitoring, and assessment of treatment outcome. This review discusses the development of mathematical models of the heart and circulation, with particular reference to the closed-loop CircAdapt model, and how the model performs under both normal and pathophysiological (pulmonary hypertensive) conditions.

Cardiac remodeling in rats with renal failure shows interventricular differences

Chronic renal failure (CRF) is associated with an increased incidence of cardiovascular diseases. Intensive research revealed a number of alterations in the heart during CRF; however, possible interventricular differences in CRF-induced cardiac remodeling have so far not been addressed. CRF was induced by two-stage surgical 5/6 nephrectomy (NX) in male Wistar rats. Cellular hypertrophy was quantified using immunohistological morphometric analysis. Contraction force and membrane potential were recorded in left and right ventricle papillary muscles with an isometric force transducer and high-resistance glass microelectrodes. Hypertrophy was present in the left ventricle (LV) of NX animals, but not in the right ventricle (RV) of NX animals, as documented by both ventricle/body weight ratios and cellular morphometric analysis of the cross-sectional area of myocytes. The contraction force was reduced in the LV of NX animals but increased in the RV of NX animals compared with sham-operated rats. Rest potentiation of contraction force was relatively more pronounced in the LV of NX rats. Fifty percent substitution of extracellular sodium with lithium significantly increased the contraction force only in the LV of NX animals. Action potential durations were shortened in both ventricles of CRF animals. Cardiac structural and contractile remodeling in CRF shows significant interventricular differences. CRF induces hypertrophy of the LV but not of the RV. LV hypertrophy was associated with a reduction of contraction force, whereas in the RV, the contraction force was enhanced. Partial recovery of contractile function of the LV by rest potentiation or lithium substitution indicates a role of the Na(+)/Ca(2+) exchanger in this phenomenon.

Estrogen receptor-beta prevents cardiac fibrosis

Development of cardiac fibrosis portends the transition and deterioration from hypertrophy to dilation and heart failure. Here we examined how estrogen blocks this important development. Angiotensin II (AngII) and endothelin-1 induce cardiac hypertrophy and fibrosis in humans. and we find that these agents directly stimulate the transition of the cardiac fibroblast to a myofibroblast. AngII and endothelin-1 stimulated TGFβ1 synthesis in the fibroblast, an inducer of fibrosis that signaled via c-jun kinase to Sma- and Mad-related protein 3 phosphorylation and nuclear translocation in myofibroblasts. As a result, mesenchymal proteins fibronectin and vimentin were produced, as were collagens I and III, the major forms found in fibrotic hearts. 17β-Estradiol (E2) or dipropylnitrile, an estrogen receptor (ER)β agonist, comparably blocked all these events, reversed by estrogen receptor (ER)β small interfering RNA. E2 and dipropylnitrile signaling through cAMP and protein kinase A prevented myofibroblast formation and blocked activation of c-jun kinase and important events of fibrosis. In the hearts of ovariectomized female mice, cardiac hypertrophy and fibrosis were induced by AngII infusion and prevented by E2 administration to wild type but not ERβ knockout rodents. Our results establish the cardiac fibroblast as an important target for hypertrophic/fibrosis-inducing peptides the actions of which were mitigated by E2/ERβ acting in these stromal cells.

Effect of systemic hypertension on right ventricular morphology and function: an echocardiographic study

BACKGROUND

Hypertension is an important cardiovascular risk factor worldwide. It is associated with left ventricular hypertrophy (LVH). Both diastolic and systolic dysfunction may occur in hypertensive heart disease. The ventricles are structurally and functionally interdependent on each other. This was an echocardiographic study intended to describe the impact of left ventricular pressure overload and hypertrophy due to hypertension on right ventricular morphology and function.

METHODS

One hundred subjects with systemic hypertension and 50 age- and gender-matched normotensive control subjects were used for this study. Two-dimensional (2-D), M-mode and Doppler echocardiographic studies were done to evaluate the structure and function of both ventricles. Data analysis was done using the SPSS 16.0 (Chicago, Ill). Statistical significance was taken as p < 0.05.

RESULTS

Age and gender were comparable between the two groups. Hypertensive subjects had significantly increased left ventricular end-diastolic dimensions, posterior wall thickness, interventricular septal thickness, left atrial dimensions and left ventricular mass and index. The mitral valve E/A ratio was reduced among hypertensive subjects when compared to normal controls (1.15 ± 0.75 vs 1.44 ± 0.31, respectively; p < 0.05). A similar pattern was found in the tricuspid E/A ratio (1.14 ± 0.36 vs 1.29 ± 0.30, respectively; p < 0.05). Hypertensive subjects also had reduced right ventricular internal dimensions (20.7 ± 8.0 vs 23.1 ± 3.1 mm, respectively; p < 0.001) but similar peak pulmonary systolic velocity. The mitral e/a ratio correlated well with the tricuspid e/a ratio.

CONCLUSION

Systemic hypertension is associated with right ventricular morphological and functional abnormalities. Right ventricular diastolic dysfunction may be an early clue to hypertensive heart disease.

Relation of cardiovascular risk factors to right ventricular structure and function as determined by magnetic resonance imaging (results from the multi-ethnic study of atherosclerosis)

The effect of cardiovascular risk factors on the left ventricle is well known but their effect on right ventricle has not been studied using advanced imaging techniques. The purpose of the present study was to determine the relation between the cardiovascular risk factors and right ventricular (RV) structure and function and its interaction with the left ventricle. Cardiac magnetic resonance images from 4,204 participants free of clinical cardiovascular disease in the Multi-Ethnic Study of Atherosclerosis were analyzed. Multivariate linear regression models were used to study the cross-sectional association between individual RV parameters and risk factors. All RV parameters, except for ejection fraction, decreased with age (p <0.0001). The RV mass was positively associated with systolic blood pressure (+0.4 g, p <0.0001) and high-density lipoprotein cholesterol (+0.2 g, p <0.0001). It was inversely related with diastolic blood pressure (-0.3 g, p <0.0001) and total cholesterol (-0.2 g, p <0.01). The RV end-diastolic volume was positively associated with systolic blood pressure (+1.6 ml, p <0.01) and high-density lipoprotein cholesterol (+1.8 ml, p <0.0001). It was inversely related with diastolic blood pressure (-2.2 ml, p <0.01), total cholesterol (-1.4 ml, p <0.0001), current smoking (-2.7 ml, p <0.05), and diabetes mellitus (-3.1 ml, p <0.01). The RV ejection fraction was positively associated with systolic blood pressure (+1.0%, p <0.0001), high-density lipoprotein cholesterol (+0.4%, p <0.0001) and inversely with diastolic blood pressure (-0.7%, p <0.0001). In conclusion, the mass and volumes of the right ventricle decrease with age. Cardiovascular risk factors, especially blood pressure and high-density lipoprotein cholesterol, are associated with subclinical changes in the RV mass and volume.

Assessment of right ventricular systolic function using tricuspid annular-plane systolic excursion in Nigerians with systemic hypertension

AIM

Right ventricular (RV) systolic function in patients with hypertensive heart disease (HHD) is not well characterised. The primary aim of this study was to assess the systolic function of the right ventricle in patients with HHD using tricuspid annular-plane systolic excursion (TAPSE).

METHODS

The study was cross-sectional in design and carried out in Kano, Nigeria. Patients were recruited if they had HHD on echocardiography and were at least 15 years of age. Patients with other cardiac pathologies such as ischaemic and valvular heart diseases were excluded. Patients were considered to have abnormal RV systolic function if they had reduced values of TAPSE ( < 15 mm). A p-value of < 0.05 was considered statistically significant.

RESULTS

A total of 186 patients were serially recruited over seven months. Of these, 131 (70.4%) had normal RV systolic function (group 1) and 55 patients (29.6%) had abnormal function (group 2). Group 2 patients were older (p = 0.002) and had a higher prevalence of peripheral oedema (p = 0.002), moderate to severe dyspnoea, higher heart rate and lower left ventricular ejection fraction (p < 0.001). Atrial arrhythmias were also more prevalent among group 2 patients (p < 0.05). The best correlate to TAPSE was the septal mitral annularplane systolic excursion (r = +0.541, p < 0.001). Several variables such as age predicted the presence of reduced TAPSE.

CONCLUSION

The study found that almost one-third of patients with HHD in Kano had RV systolic dysfunction as defined by reduced TAPSE, and these patients had a greater prevalence of factors associated with morbidity and mortality.

Right ventricular dysfunction in early systemic hypertension: a tissue Doppler imaging study in patients with high-normal and mildly increased arterial blood pressure

PURPOSE

To analyze the relationship between increasing systemic blood pressure (BP) and right ventricular (RV) function.

SUBJECTS AND METHODS

Ninety-eight never-treated, nonobese patients with BP values varying from the optimal to the mild hypertensive range. Peak early diastolic (Em) and systolic (Sm) velocities were recorded at the tricuspid and mitral annuli by tissue Doppler imaging (TDI); global RV and left ventricular (LV) structure and function by conventional echo-Doppler sonography; insulin sensitivity by homeostasis model assessment (HOMA) index. Data were analyzed by 24-h systolic BP (cut-offs 117 and 130 mmHg), thus partitioning an optimal BP from an intermediate high-normal and an upper mildly increased BP stratum.

RESULTS

Em decreased in the mid-third and decelerated further in association with reduced Sm in the upper BP tertile; both correlated negatively to septal thickness and positively to homologous TDI-derived LV indices. RV and LV indices of global ventricular function, estimated pulmonary pressure, HOMA did not differ by systemic BP.

CONCLUSION

RV diastolic and systolic function deteriorates in response to slightly increased systemic BP. The process paralleled homologous changes at the LV side and was driven by interventricular septum remodeling, perhaps as a reflection of its role in RV function and biventricular interdependence. Insulin sensitivity seemed to play no relevant role.

Prevalence and clinical correlates of right ventricular hypertrophy in essential hypertension

AIM

Right ventricular hypertrophy (RVH) has been reported to be a component of cardiac damage in systemic hypertension; this evidence, however, is based on small studies and major determinants of biventricular hypertrophy are still undefined. Thus, the prevalence and clinical correlates of RVH have been investigated in essential hypertension.

METHODS

A total of 330 untreated and treated uncomplicated essential hypertensives consecutively attending a hospital out-patient hypertension clinic were considered for the analysis. All individuals underwent a quantitative echocardiographic examination as well as extensive clinical and laboratory investigations. RVH was defined by an anterior RV wall thickness equal or higher than 3.1/3.0 mm/m2 in men and women, respectively, and left ventricular hypertrophy (LVH) by LV mass index equal or higher than 51/47g/m2.7 in men and women, respectively.

RESULTS

Overall, 114 (34.5%) patients fulfilled the criteria for LVH and 111 (33.6%) for RVH; normal cardiac morphology was observed in 164 patients (49.6%), isolated RVH in 52 (15.7%), isolated LVH in 55 (16.6%) and bi-ventricular hypertrophy in 59 (17.8%). In a logistic regression analysis, modifiable risk factors such as abdominal obesity (OR 3.41, CI 1.73-6.74, P = 0.0004), LV mid-wall fractional shortening (OR 2.48, CI 1.26-4.85, P = 0.008), fasting blood glucose (OR 2.47, CI 1.25-4.89, P = 0.009) and systolic blood pressure (OR 2.39, CI 1.19-4.82, P = 0.014) were the major independent correlates of biventricular hypertrophy.

CONCLUSION

RVH is commonly found in systemic hypertension and is associated with LVH (i.e., biventricular hypertrophy) in approximately one-fifth of the patients seen in a specialist setting. The clinical correlates of biventricular hypertrophy suggest that this phenotype is associated with a profile of very high cardiovascular risk.