Recent Advances in Imaging of Hypertensive Heart Disease

Imaging of Cardiac Fibrosis: How Far Have We Moved From Extracellular to Cellular?

Cardiovascular disease is the leading cause of morbidity and mortality worldwide. Myocardial fibrosis plays an important role in adverse outcomes such as heart failure and arrhythmias. As the pathological response and degree of scarring, and therefore clinical presentation varies from patient to patient, early detection of fibrosis is crucial for identifying the appropriate treatment approach and forecasting the progression of a disease along with the likelihood of disease-related mortality. Current imaging modalities provides information about either decreased function or extracellular signs of fibrosis. Targeting activated fibroblasts represents a burgeoning approach that could offer insights prior to observable functional alterations, presenting a promising focus for potential anti-fibrotic therapeutic interventions at cellular level. In this article, we provide an overview of imaging cardiac fibrosis and discuss the role of different advanced imaging modalities with the focus on novel non-invasive imaging of activated fibroblasts.

Left ventricular hypertrophy: hypertensive or hypertrophic cardiomyopathy? What a dilemma! A case report

In the presence of the left ventricle hypertrophy (LVH), the differential diagnosis with hypertrophic cardiomyopathy (HCM) or some phenocopy must be always considered, which can be easily suspected when the hypertrophy is markedly asymmetric. However, when the hypertrophy is homogeneous, especially if the patient has concomitant hypertension, it may be a challenge to distinguish between hypertensive and HCM, although some clinical features may help us to suspect it. In addition, patients with HCM may present with exertional angina due to microcirculation involvement in the setting of the hypertrophy itself or dynamic obstruction in the left ventricular outflow tract, but in some cases, the presence of concomitant coronary artery disease must be suspected as the cause of angina, especially if the patient has an intermediate or high-risk probability of having ischemic heart disease. We present the case of a 46-year-old Afro-American man with poorly controlled hypertension who was found to have severe LVH, and who presented with symptoms of exertional angina during follow-up. We will review the clinical features that can help us in the differential diagnosis in this context.

Radiotherapy-induced diffuse myocardial fibrosis in early-stage breast cancer patients - multimodality imaging study with six-year follow-up

BACKGROUND

Breast radiotherapy (RT) induces diffuse myocardial changes, which may increase the incidence of heart failure with preserved ejection fraction. This study aimed to evaluate the early signs of diffuse fibrosis after RT and their evolution during a six-year follow-up.

METHODS

Thirty patients with early-stage left-sided breast cancer were studied with echocardiography and electrocardiography (ECG) at baseline, after RT, and at three-year and six-year follow-up visits. Echocardiography analysis included an off-line analysis of integrated backscatter (IBS). ECG was analysed for fragmented QRS (fQRS). In addition, cardiac magnetic resonance (CMR) imaging was performed at the six-year control. The left ventricle 16-segment model was used in cardiac imaging, and respective local radiation doses were analysed.

RESULTS

Regional myocardial reflectivity in inferoseptal segments increased by 2.02 (4.53) dB (p = 0.026) and the percentage of leads with fQRS increased from 9.2 to 16.4% (p = 0.002) during the follow-up. In CMR imaging, abnormal extracellular volume (ECV) and T1 mapping values were found with anteroseptal and apical localization in a median of 3.5 (1.00-5.75) and 3 (1.25-4.00) segments, respectively. A higher left ventricle radiation dose was associated with an increased likelihood of having changes simultaneously in CMR and echocardiography (OR 1.26, 95% Cl. 1.00-1.59, p = 0.047).

CONCLUSIONS

After radiotherapy, progressive changes in markers of diffuse myocardial fibrosis were observed in a multimodal manner in ECG and echocardiography. Changes in echocardiography and abnormal values in CMR were localized in the septal and apical regions, and multiple changes were associated with higher radiation doses.

Hypertensive Heart Disease-The Imaging Perspective

Hypertensive heart disease (HHD) develops in response to the chronic exposure of the left ventricle and left atrium to elevated systemic blood pressure. Left ventricular structural changes include hypertrophy and interstitial fibrosis that in turn lead to functional changes including diastolic dysfunction and impaired left atrial and LV mechanical function. Ultimately, these changes can lead to heart failure with a preserved (HFpEF) or reduced (HFrEF) ejection fraction. This review will outline the clinical evaluation of a patient with hypertension and/or suspected HHD, with a particular emphasis on the role and recent advances of multimodality imaging in both diagnosis and differential diagnosis.

Hypertensive Heart Disease: A Narrative Review Series-Part 1: Pathophysiology and Microstructural Changes

Sustained hypertension causes structural, functional, and neurohumoral abnormalities in the heart, a disease commonly termed hypertensive heart disease (HHD). Modern concepts of HHD, including processes of remodeling leading to the development of various LVH patterns, HF patterns accompanied by micro- and macrovasculopathies, and heart rhythm and conduction disturbances, are missing in the available definitions, despite copious studies being devoted to the roles of myocardial and vascular fibrosis, and neurohumoral and sympathetic regulation, in HHD development and progression. No comprehensive and generally accepted universal definition and classification of HHD is available to date, implementing diagnostic criteria that incorporate all the possible changes and adaptions to the heart. The aim of this review series is to summarize the relevant literature and data, leading to a proposal of a definition and classification of HHD. This first article reviews the processes of initial myocardial remodeling, and myocardial and vascular fibrosis, occurring in HHD. We discuss important pathophysiological and microstructural changes, the different patterns of fibrosis, and the biomarkers and imaging used to detect fibrosis in HHD. Furthermore, we review the possible methods of targeting myocardial fibrosis in HHD, and highlight areas for further research.

Evaluation of left ventricular blood flow kinetic energy in patients with hypertension by four-dimensional flow cardiovascular magnetic resonance imaging: a preliminary study

OBJECTIVES

To evaluate the intra-cavity left ventricular (LV) blood flow kinetic energy (KE) parameters using four-dimensional (4D) flow cardiovascular magnetic resonance (CMR) in patients with hypertension (HTN).

METHODS

Forty-two HTN patients and twenty age-/gender-matched healthy controls who underwent CMR including cines, pre-/post-T1 mapping, and whole-heart 4D flow imaging were retrospectively evaluated. HTN patients were further divided into two subgroups: with preserved ejection fraction (HTN-pEF) and with reduced ejection fraction (HTN-rEF). KE parameters were indexed to LV end-diastolic volume (EDV) to obtain averaged LV, minimal, systolic, diastolic, peak E-wave, peak A-wave, E-wave, and A-wave KEi_EDV, as well as the proportion of in-plane LV KE (%), the time difference (TD). These parameters were compared between the HTN group and healthy controls, also between two subgroups. The correlation of LV blood flow KE parameters with LV function and extracellular volume fraction (ECV) were analyzed in the HTN group using multivariate regression analysis.

RESULTS

Peak E-wave KEi_EDV in the HTN group was significantly lower (p = 0.01), while in-plane KE and TD were significantly higher (all p < 0.01) than those in healthy controls. Compared to the HTN-pEF subgroup, the proportion of in-plane KE and TD was significantly increased in the HTN-rEF subgroup (all p < 0.01). Only the proportion of in-plane KE demonstrated an independent correlation with ECV (β* = 0.59, p < 0.01).

CONCLUSIONS

The decreased peak E-wave KEi_EDV and the increased proportion of in-plane KE, TD reflected the alterations of LV blood flow in HTN patients, and the proportion of in-plane KE was independently associated with ECV.

KEY POINTS

• 4D flow CMR demonstrated that the peak E-wave KEi_EDV was decreased, while the in-plane KE and time difference (TD) were increased in hypertensive (HTN) patients. • The proportion of in-plane KE and TD was further increased in HTN patients with reduced ejection fraction than in HTN patients with preserved ejection fraction, and the proportion of in-plane KE was independently associated with extracellular volume fraction in HTN patients. • 4D flow CMR intra-cavity blood flow KE parameters might reveal the LV hemodynamic status in preclinical HTN patients.

Cardiac Magnetic Resonance in Hypertensive Heart Disease: Time for a New Chapter

Hypertension is one of the most important cardiovascular risk factors, associated with significant morbidity and mortality. Chronic high blood pressure leads to various structural and functional changes in the myocardium. Different sophisticated imaging methods are developed to properly estimate the severity of the disease and to prevent possible complications. Cardiac magnetic resonance can provide a comprehensive assessment of patients with hypertensive heart disease, including accurate and reproducible measurement of left and right ventricle volumes and function, tissue characterization, and scar quantification. It is important in the proper evaluation of different left ventricle hypertrophy patterns to estimate the presence and severity of myocardial fibrosis, as well as to give more information about the benefits of different therapeutic modalities. Hypertensive heart disease often manifests as a subclinical condition, giving exceptional value to cardiac magnetic resonance as an imaging modality capable to detect subtle changes. In this article, we are giving a comprehensive review of all the possibilities of cardiac magnetic resonance in patients with hypertensive heart disease.

Subclinical HMOD in Hypertension: Left Ventricular Diastolic Dysfunction

Arterial hypertension represents an important risk factor for the development of cardiac, vascular and renal events, predisposing to heart failure, acute coronary syndromes, peripheral artery disease, stroke, and chronic renal disease. Arterial hypertension leads to the development of subclinical hypertension mediated organ damage (HMOD) which has prognostic relevance and may influence the choice of treatment options. Alterations of cardiac structure and function represent the more widely assessed form of HMOD. This manuscript will focus on the diagnostic opportunities, prognostic significance and treatment of diastolic dysfunction alterations.

Advanced imaging tools for evaluating cardiac morphological and functional impairment in hypertensive disease

Arterial hypertension represents a systemic burden, and it is responsible of various morphological, functional and tissue modifications affecting the heart and the cardiovascular system. Advanced imaging techniques, such as speckle tracking and three-dimensional echocardiography, cardiac magnetic resonance, computed tomography and PET-computed tomography, are able to identify cardiovascular injury at different stages of arterial hypertension, from subclinical alterations and overt organ damage to possible complications related to pressure overload, thus giving a precious contribution for guiding timely and appropriate management and therapy, in order to improve diagnostic accuracy and prevent disease progression. The present review focuses on the peculiarity of different advanced imaging tools to provide information about different and multiple morphological and functional aspects involved in hypertensive cardiovascular injury. This evaluation emphasizes the usefulness of the emerging multiimaging approach for a comprehensive overview of arterial hypertension induced cardiovascular damage.

Cardiac Magnetic Resonance Radiomics Reveal Differential Impact of Sex, Age, and Vascular Risk Factors on Cardiac Structure and Myocardial Tissue

Background: Cardiovascular magnetic resonance (CMR) radiomics analysis provides multiple quantifiers of ventricular shape and myocardial texture, which may be used for detailed cardiovascular phenotyping. Objectives: We studied variation in CMR radiomics phenotypes by age and sex in healthy UK Biobank participants. Then, we examined independent associations of classical vascular risk factors (VRFs: smoking, diabetes, hypertension, high cholesterol) with CMR radiomics features, considering potential sex and age differential relationships. Design: Image acquisition was with 1.5 Tesla scanners (MAGNETOM Aera, Siemens). Three regions of interest were segmented from short axis stack images using an automated pipeline: right ventricle, left ventricle, myocardium. We extracted 237 radiomics features from each study using Pyradiomics. In a healthy subset of participants (n = 14,902) without cardiovascular disease or VRFs, we estimated independent associations of age and sex with each radiomics feature using linear regression models adjusted for body size. We then created a sample comprising individuals with at least one VRF matched to an equal number of healthy participants (n = 27,400). We linearly modelled each radiomics feature against age, sex, body size, and all the VRFs. Bonferroni adjustment for multiple testing was applied to all p-values. To aid interpretation, we organised the results into six feature clusters. Results: Amongst the healthy subset, men had larger ventricles with dimmer and less texturally complex myocardium than women. Increasing age was associated with smaller ventricles and greater variation in myocardial intensities. Broadly, all the VRFs were associated with dimmer, less varied signal intensities, greater uniformity of local intensity levels, and greater relative presence of low signal intensity areas within the myocardium. Diabetes and high cholesterol were also associated with smaller ventricular size, this association was of greater magnitude in men than women. The pattern of alteration of radiomics features with the VRFs was broadly consistent in men and women. However, the associations between intensity based radiomics features with both diabetes and hypertension were more prominent in women than men. Conclusions: We demonstrate novel independent associations of sex, age, and major VRFs with CMR radiomics phenotypes. Further studies into the nature and clinical significance of these phenotypes are needed.

Study on the correlation between Left Ventricular Hypertrophy and Coronary Artery disease in the very elderly patients with hypertension

Objective:

To investigate the relationship between left ventricular hypertrophy (LVH) and coronary artery disease in the very elderly (over 80 years old) patients with hypertension.

Methods:

One hundred twenty cases of very elderly patients with hypertension admitted to our hospital from March 2018 to December 2020 were selected and divided into two groups: the LVH group and the non-LVH group, all of whom were older aged over 80 years, including 62 patients in the LVH group and 58 patients in the non-LVH group. All patients underwent cardiac color Doppler ultrasound examination, 24-hour dynamic ECG examination, and coronary angiography or coronary CTA examination. The clinical data of the two groups were analyzed statistically.

Results:

There were significant differences in the number of diseased vessels, degree of coronary stenosis and vascular calcification between the two groups (P<0.05). Moreover, the results of risk factors for the degree of coronary artery disease in the two groups showed that the history of diabetes, 2hPG and LVH were independent risk factors for the three-vessel disease, while the history of LVH, FPG and alcohol intake were independent risk factors for diffuse lesions, but there was no statistical difference in the correlation between them and the degree of coronary stenosis.

Conclusion:

LVH is an independent risk factor for coronary artery stenosis and calcification in the very elderly patients with hypertension, but there is no statistical difference in the correlation between LVH and the degree of coronary stenosis.

Relationships between left ventricular mass and QRS duration in diverse types of left ventricular hypertrophy

AIMS

Hypertrophic cardiomyopathy (HCM) may be associated with very narrow QRS, while left ventricular hypertrophy (LVH) may increase QRS duration. We investigated the relationships between QRS duration and LV mass (LVM) in subtypes of abnormal LV wall thickness.

METHODS AND RESULTS

Automated measurement of LVM on MRI was correlated to automated measurement of QRS duration on ECG in HCM, left ventricular non compaction (LVNC), left ventricular hypertrophy (LVH), and controls with healthy hearts. Uni and multivariate analyses were performed between groups including explanatory variables expected to influence LVM and QRS duration. The relationships between QRS duration and LVM were further studied within each group. Two hundred and twenty-one HCM, 28 LVNC, 16 LVH, and 40 controls were retrospectively included. Mean QRS duration was 92 ms for HCM, 104 for LVNC, 110 for LVH, and 92 for controls (P < 0.01). Mean LVM was 100, 90, 108, and 68 g/m2 (P < 0.01). QRS duration, LVM, hypertension, maximal wall thickness, and late gadolinium enhancement were significantly linked to HCM in multivariate analysis (w/wo bundle branch block). An independent negative correlation was found between LVM and QRS duration in the HCM group, while the relationship was reverse in LVNC, LVH, and controls.

CONCLUSION

QRS duration increases with LVM in LVNC, LVH, or in healthy hearts, while reverse relationship is present in HCM. These relationships were independent from other parameters. These results warrant additional investigations for refining diagnosis criteria for HCM in the future.

Is there a latent left ventricular dysfunction in hypertensive patients with preserved ejection fraction?

INTRODUCTION

Early detection of left ventricular (LV) dysfunction may represent a clinical finding that would justify aggressive treatment aimed to reduce cardiovascular morbidity and mortality.

AIM

To evaluate longitudinal contractility in patients with essential hypertension and preserved LV ejection fraction (EF), in an attempt to detect latent impairment of LV systolic function.

METHODS

Prospective case-control study carried out on 121 (67 male/54 female) hypertensive patients (HTN group) with preserved EF and without any symptoms of heart failure and 39 age- and gender-matched healthy subjects as a control group. Conventional echocardiographic study, as well as 2D Longitudinal strain imaging by 2D-speckle tracking echocardiography (2D-STE), were performed.

RESULTS

Mean age of patients was 60,48 ± 10.5 years old. The LV end-diastolic diameter and LVEF were comparable between the two groups. Hypertensive patients had greater septal thickness, left ventricular mass, and maximum left atrium volume (p respectively at 0.02; 0.04; and 0.01). Only 20 patients (16.5%) had left ventricular hypertrophy (LVH). The architecture of LV was normal in 57.8 % (n=70) patients. A statistically significant difference between the two groups was found for all diastolic function parameters except Em /Ea ratio and DTEm. In comparison with normal controls, GLS was significantly attenuated in patients with HTN (-17.69 ± 4.06 % versus -22.70 ± 5.02% in controls (p=0.000) and 67 (55.4%) hypertensive patients had a GLS<-20% (in absolute value). The decrease of GLS was more marked in the hypertensive group with left ventricular hypertrophy.

CONCLUSION

The results of our study confirmed that GLS is a sensitive biomarker of subclinical myocardial dysfunction in hypertensive patients, this suggests that identifying patients at higher risk for heart failure and earlier inter¬vention may be beneficial.

Therapeutic Targeting of Interleukin-11 Signalling Reduces Pressure Overload-Induced Cardiac Fibrosis in Mice

There are currently no specific treatments for cardiac fibrosis. We tested the efficacy of a neutralising anti-IL11 antibody (X203) to reduce cardiac fibrosis in two preclinical models: transverse aortic constriction (TAC) and chronic angiotensin II infusion (AngII). In the first model, male C57BL/6J mice were subjected to TAC for 2 weeks. In the second model, mice received continuous angiotensin II for 4 weeks via subcutaneous pump. In both models, mice received either 20 mg/kg of X203 or isotype-control antibody twice-weekly, starting 24 h after surgery. Cardiac fibrosis and extracellular matrix gene expression were assessed by RT-qPCR, Western blot, histology and collagen (hydroxyproline) assays. In both models, X203 significantly reduced pro-fibrotic gene expression and myocardial fibrosis (TAC: 51% reduction in total collagen, P < 0.001, 39% in perivascular fibrosis, P < 0.001; AngII: 17% reduction in total collagen, P = 0.04, 83% in perivascular fibrosis, P < 0.001). Pharmacological targeting of IL11 reduces cardiac fibrosis in preclinical models. Figa Graphical Abstract.

Association of Hypertensive Intracerebral Hemorrhage with Left Ventricular Hypertrophy on Transthoracic Echocardiography

INTRODUCTION

Arterial hypertension is the most frequent cause for spontaneous intracerebral hemorrhage (sICH) and may also cause left ventricular hypertrophy (LVH). We sought to analyze whether hypertensive sICH etiology is associated with LVH.

METHODS

We analyzed consecutive patients with sICH who were admitted to our tertiary stroke center during a four-year period and underwent transthoracic echocardiography (TTE) as part of the diagnostic work-up. We defined hypertensive sICH as typical localization of hemorrhage in patients with arterial hypertension and no other identified sICH etiology. We defined an increased end-diastolic interventricular septal wall thickness of ≥11 mm on TTE as a surrogate parameter for LVH.

RESULTS

Among 395 patients with sICH, 260 patients (65.8%) received TTE as part of their diagnostic work-up. The median age was 71 years (interquartile range (IQR) 17), 160 patients (61.5%) were male, the median baseline National Institute of Health Stroke Scale (NIHSS) score was 8 (IQR 13). Of these, 159 (61.2%) patients had a hypertensive sICH and 156 patients (60%) had LVH. In univariable (113/159 (71.1%) vs. 43/101 (42.6%); odds ratio (OR) 3.31; 95% confidence interval (CI_95%) 1.97-5.62); and multivariable (adjusted OR 2.95; CI_95% 1.29-6.74) analysis, hypertensive sICH was associated with LVH.

CONCLUSIONS

In patients with sICH, LVH is associated with hypertensive bleeding etiology. Performing TTE is meaningful for diagnosis of comorbidities and clarification of bleeding etiology in these patients. Future studies should include long-term outcome parameters and assess left ventricular mass as main indicator for LVH.

Sporadic inclusion body myositis: no specific cardiac involvement in cardiac magnetic resonance tomography

Objective

To investigate cardiac involvement in patients with sporadic inclusion body myositis (IBM) by cardiac magnetic resonance tomography (CMR).

Methods

A case series of 20 patients with IBM underwent basic cardiac assessment and CMR including functional imaging, native and contrast-enhanced T1-weighted, and late gadolinium enhancement (LGE) imaging.

Results

All IBM patients reported no cardiac symptoms. Echocardiography was normal in 16/17 IBM patients. In CMR, IBM patients had normal ejection fractions (mean LVEF 63 ± 7%) and ventricular mass. They had reduced left (mean 55 versus 88 ml) and right ventricular stroke volumes (mean 54 versus 86 ml) and increased early myocardial enhancement (pathological T1 Ratio in 44% versus 5%), as compared to age- and gender-matched controls. Since arterial hypertension was more often observed in IBM patients, hypertensive heart disease can also be causative for these changes. Late gadolinium enhancement did not differ statistically from healthy controls. There was no apparent association between elevated biomarkers, echocardiography and CMR.

Conclusion

CMR revealed subtle changes in cardiac geometry and tissue characterization in IBM patients when compared to a gender- and age-matched control group. Findings in CMR indicated a higher extent of diffuse myocardial fibrosis as well as smaller left ventricular stroke volumes. These alterations may be due to a higher prevalence of arterial hypertension in the IBM cohort.