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.

Salt-induced effects on microvascular function: A critical factor in hypertension mediated organ damage.

Salt has been linked very closely to the occurrence and complications of arterial hypertension. A large percentage of patients with essential hypertension are salt-sensitive; that is, their blood pressure increases with increased salt intake and decreases with its reduction. For this reason, emphasis is placed on reducing salt intake to better regulate blood pressure. In day-to-day clinical practice this is viewed as mandatory for hypertensive patients who are judged to be salt-sensitive. Previous studies have highlighted the negative effect of high-salt diets on macrovascular function, which also affects blood pressure levels by increasing peripheral resistances. More recent studies provide a better overview of the pathophysiology of microvascular disorders and show that they are largely due to the overconsumption of salt. Microvascular lesions, which have a major impact on the functioning of vital organs, are often not well recognized in clinical practice and are not paid sufficient attention. In general, the damage caused by hypertension to the microvascular network is likely to be overlooked, while reversion of the damage is only rarely considered as a therapeutic target by the treating physician. The purpose of this review is to summarize the impact and the harmful consequences of increased salt consumption in the microvascular network, their significance and pathophysiology, and at the same time to place some emphasis on their treatment and reversion, mainly through diet.

MicroRNAs in Peripheral Mononuclear Cells as Potential Biomarkers in Hypertensive Patients With Heart Failure With Preserved Ejection Fraction.

BACKGROUND: MicroRNAs (miRs) regulate gene expression and play an important role in ventricular and vascular remodeling. However, there are limited data regarding their role in heart failure with preserved ejection fraction (HFpEF). The aim of this study was to assess gene expression of miR-1, miR-133a, miR-21, miR-208b, miR-499, and miR-26b in peripheral blood mononuclear cells (PBMCs) in hypertensive patients with HFpEF and to evaluate their association with their exercise capacity. METHODS: We included 56 hypertensive patients with HFpEF (age 67.29 ± 7.75 years). Forty-two hypertensive patients without HFpEF (age 66.83 ± 7.17 years) served as controls. All subjects underwent a cardiopulmonary exercise test (CPXT). PBMCs were isolated and levels of miRs were determined by quantitative real-time reverse transcription polymerase chain reaction. RESULTS: For hypertensive patients with HFpEF, higher expression levels in PBMCs were found only for miR-26b (7.6 ± 7.3 vs. 4.0 ± 3.6, P = 0.002), miR-208b (28.8 ± 35.3 vs. 7.5 ± 13.3, P < 0.001), and miR-499 (14.2 ± 22.4 versus 3.5 ± 2.9, P = 0.001). The strongest correlations with CPXT parameters were found for miR-208b levels, which had a positive correlation with maximal oxygen uptake (peakVO2) (r = 0.671, P < 0.001), exercise duration (r = 0.445, P = 0.001), and minute ventilation-carbon dioxide production relationship (VE/VCO2) (r = 0.437, P = 0.001) in the HFpEF group. CONCLUSIONS: miR-26b, miR-208b, and miR-499 show a distinct in profile in hypertensive patients with HFpEF that is related with functional capacity. Further studies are needed to assess the role of miRs as prognostic tools or as therapeutic targets in those patients.

Low Levels of MicroRNA-21 Are a Marker of Reduced Arterial Stiffness in Well-Controlled Hypertension.

MicroRNAs (miRNAs) play a crucial role in myocardial and vascular remodeling and have emerged as potential diagnostic and prognostic biomarkers or as therapeutic targets. The authors aimed to investigate the expression profile of selected miRNAs in the peripheral blood of patients with well-controlled essential hypertension in relation to arterial stiffness. Expression levels of miRNAs miRNA-1, miRNA-133a, miRNA-26b, miRNA-208b, miRNA-499, and miRNA-21 in peripheral blood mononuclear cells were quantified by real-time reverse transcription polymerase chain reaction. Carotid-femoral pulse wave velocity (cfPWV) and carotid radial pulse wave velocity (crPWV) were evaluated at baseline and after 1 year of effective antihypertensive therapy. A total of 95 patients (50 men, mean age 62±9 years) with well-controlled essential hypertension were included in the analysis. Only miRNA-21 was independently correlated with changes in both cfPWV and crPWV, independently of blood pressure levels (r=-0.56 and r=-0.46, respectively; P<.001 for both). Low levels of miRNA-21 are strongly associated with an improvement in arterial stiffness in patients with well-controlled essential hypertension, independently of their blood pressure levels. These data highlight the significance of miRNA-21 in vascular remodeling and its role as a potential prognostic marker and future therapeutic target.