Therapeutic approaches to diastolic dysfunction

Early Left Ventricular Diastolic Dysfunction and Abnormal Left Ventricular-left Atrial Coupling in Asymptomatic Patients With Hypertension: A Cardiovascular Magnetic Resonance Feature Tracking Study

PURPOSE

Hypertension (HTN) patients suffer from increased risk of left ventricular (LV) diastolic dysfunction and LV hypertrophy (LVH). Evaluation of early LV diastolic function requires accurate noninvasive diagnostic tools. The aim of this study was to evaluate whether cardiovascular magnetic resonance feature-tracking (CMR-FT) could detect early LV dysfunction and evaluate LV-left atrium (LA) correlation in HTN patients.

MATERIALS AND METHODS

In all, 89 HTN patients and 38 age-matched and sex-matched controls were retrospectively enrolled and underwent CMR examination. HTN patients were divided into LVH (n=38) and non-LVH (n=51) groups. All LV deformation parameters were analyzed in radial, circumferential, and longitudinal directions, including peak strain, peak systolic strain rate and peak diastolic strain rate (PDSR), LA strain and strain rate (SR), including LA reservoir function (εs, SRs), conduit function (εe, SRe), and booster pump function (εa, SRa).

RESULTS

Compared with controls, the LV PDSR in radial, circumferential, and longitudinal directions and the LA reservoir and conduit function were significantly impaired in HTN patients regardless of LVH (all P<0.05). LV longitudinal and radial PDSR were correlated with LA reservoir and conduit function (all P<0.01). Among all LV and LA impaired deformation parameters, the longitudinal PDSR (in LV) and εe (in LA) were the most sensitive parameter for the discrimination between non-LVH and healthy volunteers, with an area under the curve of 0.70 (specificity 79%, sensitivity 55%) and 0.76 (specificity 95%, sensitivity 49%), respectively. The area under the curve reached 0.81 (specificity 82%, sensitivity 75%) combined with the longitudinal PDSR and εe.

CONCLUSION

CMR-FT could detect early LV diastolic dysfunction in HTN patients, which might be associated with LA reservoir and conduit dysfunction.

Evaluation of Left Ventricular Systolic Function and Mass in Primary Hypertensive Patients by Echocardiography

Hypertension is an independent risk factor for cardiovascular diseases. The accurate evaluation of cardiovascular risk is of paramount importance in the management of hypertensive patients. Conventional echocardiographic methods have provided the assessment of left ventricular systolic function and mass for many years. Tissue Doppler imaging, 3-dimensional echocardiography, and speckle tracking echocardiography are newer echocardiographic modalities for the left ventricular systolic function and mass quantification. The major emphasis of this review is to evaluate the left ventricular systolic function and mass by conventional and newly developed echocardiographic in hypertensive patients.

Diastolic Dysfunction and Hypertension

Left ventricular (LV) diastolic dysfunction (LVDD) is characterized by alterations in LV diastolic filling, and is a strong predictor of cardiovascular events and heart failure. Hypertension is the most important risk factor for LVDD in the community and promotes LVDD through several mechanisms, including hemodynamic overload and myocardial ischemia. Associated factors such as age, ethnicity, dietary sodium, obesity, diabetes mellitus, and chronic kidney disease also contribute to LVDD in hypertensive individuals. Blood pressure lowering using antihypertensive medications can improve LVDD; however, it remains unclear whether this improvement in LV diastolic function can improve cardiovascular outcomes.

Recommendations on the Use of Echocardiography in Adult Hypertension: A Report from the European Association of Cardiovascular Imaging (EACVI) and the American Society of Echocardiography (ASE)

Hypertension remains a major contributor to the global burden of disease. The measurement of blood pressure continues to have pitfalls related to both physiological aspects and acute variation. As the left ventricle (LV) remains one of the main target organs of hypertension, and echocardiographic measures of structure and function carry prognostic information in this setting, the development of a consensus position on the use of echocardiography in this setting is important. Recent developments in the assessment of LV hypertrophy and LV systolic and diastolic function have prompted the preparation of this document. The focus of this work is on the cardiovascular responses to hypertension rather than the diagnosis of secondary hypertension. Sections address the pathophysiology of the cardiac and vascular responses to hypertension, measurement of LV mass, geometry, and function, as well as effects of treatment.

Increased extracellular volume and altered mechanics are associated with LVH in hypertensive heart disease, not hypertension alone

OBJECTIVES

The goal of this study was to assess the relationship among extracellular volume (ECV), native T1, and systolic strain in hypertensive patients with left ventricular hypertrophy (HTN LVH), hypertensive patients without LVH (HTN non-LVH), and normotensive controls.

BACKGROUND

Diffuse myocardial fibrosis in HTN LVH patients, as reflected by increased ECV and native T1, may be an underlying mechanism contributing to increased cardiovascular risk compared with HTN non-LVH subjects and controls. Furthermore, increased diffuse fibrosis in HTN LVH subjects may be associated with reduced peak systolic and early diastolic strain rate compared with the other 2 groups.

METHODS

T1 mapping was performed in 20 HTN LVH (mean age, 55 ± 11 years), 23 HTN non-LVH (mean age, 61 ± 12 years), and 22 control subjects (mean age, 54 ± 7 years) on a Siemens 1.5-T Avanto (Siemens Healthcare, Erlangen, Germany) using a previously validated modified look-locker inversion-recovery pulse sequence. T1 was measured pre-contrast and 10, 15, and 20 min after injection of 0.15 mmol/kg gadopentetate dimeglumine, and the mean ECV and native T1 were determined for each subject. Measurement of circumferential strain parameters were performed using cine displacement encoding with stimulated echoes.

RESULTS

HTN LVH subjects had higher native T1 compared with controls (p < 0.05). HTN LVH subjects had higher ECV compared with HTN non-LVH subjects and controls (p < 0.05). Peak systolic circumferential strain and early diastolic strain rates were reduced in HTN LVH subjects compared with HTN non-LVH subjects and controls (p < 0.05). Increased levels of ECV and native T1 were associated with reduced peak systolic and early diastolic circumferential strain rate across all subjects.

CONCLUSIONS

HTN LVH patients had higher ECV, longer native T1 and associated reduction in peak systolic circumferential strain, and early diastolic strain rate compared with HTN non-LVH and control subjects. Measurement of ECV and native T1 provide a noninvasive assessment of diffuse fibrosis in hypertensive heart disease.

Imaging in hypertensive heart disease

Hypertensive heart disease is the target organ response to arterial hypertension. Left ventricular hypertrophy represents an important predictor for cardiovascular events. Myocardial fibrosis, a common end point in hypertensive heart disease, has been linked to the development of left ventricular hypertrophy and diastolic dysfunction. Echocardiography is clinically useful in the detection of left ventricular hypertrophy and the assessment of diastolic function. Although echocardiography is more widely available, cardiac magnetic resonance has been demonstrated to be more reproducible for the estimation of left ventricular mass. Future developments in cardiac magnetic resonance techniques may facilitate the quantification of diffuse fibrosis that occurs in hypertensive heart disease. Thus, advances in cardiac imaging provide comprehensive, noninvasive tools for imaging left ventricular hypertrophy, diastolic dysfunction, myocardial fibrosis and ischemia observed in hypertensive heart disease. The objective of this article is to summarize the state-of-the-art and the future of multimodality imaging of hypertensive heart disease.