Effect of Masked, White-Coat, and Sustained Hypertension on Coronary Flow Reserve and Peripheral Endothelial Functions

A study of endothelial and platelet microvesicles across different hypertension phenotypes

Rather than being mere biomarkers reflecting generalized vascular injury, endothelial- (EMVs) and platelet-derived (PMVs) microvesicles have emerged as potent regulators of intercellular communication with significant biologic effects in vascular homeostasis and several pathophysiological responses including inflammation and thrombosis. So far, studies in hypertension are scarce, whereas no studies exist in masked hypertension (MH). We measured EMVs and PMVs in untreated, newly diagnosed hypertensives (HTs) and MHs compared to normotensive controls (NTs), and associated them with various cardiovascular risk factors. Sustained hypertension (SHT) and MH were defined according to standard blood pressure (BP) criteria. All HTs were free of cardiovascular disease and medications. Microvesicles' quantitation and detection were performed by flow cytometry by using cell-specific antibodies and corresponding isotypes (anti-CD105 and anti-CD144 for EMVs, anti-CD42a for PMVs, and Annexin V-fluorescein isothiocyanate for all microvesicles). In this study, we included 59 HTs (44 SHTs and 15 MHs) and 27 NTs. HTs had significantly elevated EMVs (p = 0.004), but not PMVs compared to NTs. MHs had significantly elevated EMVs compared to NTs (p = 0.012) but not compared to SHTs. Furthermore, EMVs significantly correlated with ambulatory (r = 0.214-0.284), central BP (r = 0.247-0.262), and total vascular resistance (r = 0.327-0.361). EMVs are increased not only in SHTs but also in MHs, a hypertension phenotype with a cardiovascular risk close to SHT. EMVs have emerged as active contributors to thromboinflammation and vascular damage and may explain, in part, the adverse cardiovascular profile of SHTs and MHs.

Risk of Target Organ Damage in Patients with Masked Hypertension versus Sustained Hypertension: A Meta-analysis

Objective: To compare the risk of target organ damage in masked hypertension (MH) and sustained hypertension (SH).Methods: A systematic review and meta-analysis was performed. A search of PubMed, Embase, and the Cochrane Library of relevant case-control studies was performed from inception to December 2019, and articles on MH and SH selected according to the inclusion criteria were analyzed. The primary end point was target organ damage in the heart. The secondary end points were target organ damage in the kidneys and blood vessels.Results: Seventeen studies that met the screening criteria were included in the meta-analysis. Compared with the SH group, in the MH group carotid intima-media thickness (IMT) and E/A ratio were significantly greater and the prevalence of left ventricular remodeling and the pulse wave velocity were significantly lower. Other indicators in the heart, kidneys, and blood vessels were not statistically different between the two groups. IMT: P=0.01, E/A ratio: P=0.01, prevalence of left ventricular remodeling: P=0.02, pulse wave velocity: P=0.01.Conclusion: Our study has shown that MH may have almost the same degree of target organ damage as SH, so clinicians may need to consider target organ damage.

Cardiovascular Alterations and Management of Patients With White Coat Hypertension: A Meta-Analysis

A large and growing body of literature has focused on the association between "white coat hypertension" (WCH) and the underlying target organ damage. The evidence suggests that WCH is may not an entirely benign phenomenon. However, whether patients with WCH should receive antihypertensive drugs is unresolved. Therefore, we performed a meta-analysis to fully determine the ability of WCH to alter cardiovascular structure and to determine whether patients with WCH could benefit from drug intervention. Medline, EMBASE, and the Cochrane Library were searched from inception through 21 Oct 2019. A total of 25 studies (8,100 individuals) were included. In participants with WCH, values of aortic pulse wave velocity, augmentation index, intima-media thickness, interventricular septum thickness, left ventricular posterior wall thickness, and left ventricular mass index were lower than those with sustained hypertension, but greater than those in the normotensive group. Of note, antihypertensive drug therapy did not reduce the risk of cardiovascular events in patients with WCH. WCH is accompanied by alterations of cardiovascular structure; however, the benefits from antihypertensive therapy are limited.

White-coat hypertension, as defined by ambulatory blood pressure monitoring, and subclinical cardiac organ damage: a meta-analysis

AIM

: The clinical and prognostic relevance of white-coat hypertension (WCH) has not been fully elucidated; in particular, the association of this blood pressure phenotype with suclinical organ damage remains unclear. We performed a systematic meta-analysis in order to provide a comprehensive information on cardiac structural and functional changes in WCH, as defined by ambulatory blood pressure monitoring.

DESIGN

Studies were identified by the following search terms: 'white-coat hypertension', 'isolated clinic hypertension', 'cardiac organ damage', 'target organ damage', 'left ventricle', 'left ventricular hypertrophy', 'cardiac hypertrophy', 'ventricular dysfunction', and 'echocardiography'.

RESULTS

A total of 7382 untreated adult patients (2493 normotensive, 1705 WCH, and 3184 hypertensive individuals) included in 25 studies were considered. Left ventricular mass index was higher in WCH than in normotensive patients [standardized difference in mean (SDM) 0.50, P < 0.01]; mitral E/A ratio was lower (SDM -0.27, P < 0.01) and left atrium larger (SDM 0.29, P < 0.05) in WCH than in the normotensive counterparts. Hypertensive patients showed a greater left ventricular mass index (SDM 0.42, P < 0.01), reduced E/A (SDM -0.15, P < 0.01), and larger left atrium diameter (SDM 0.27, P < 0.01) than WCH patients.

CONCLUSIONS

Our meta-analysis shows that alterations in cardiac structure and function in WCH patients, as defined by ambulatory blood pressure monitoring, are intermediate between sustained hypertensive patients and normotensive controls. The study supports the view that WCH should not be further considered a fully benign entity.

Influence of White-Coat Hypertension on Left Ventricular Deformation 2- and 3-Dimensional Speckle Tracking Study

We sought to compare left ventricular deformation in subjects with white-coat hypertension to normotensive and sustained hypertensive patients. This cross-sectional study included 139 untreated subjects who underwent 24-hour ambulatory blood pressure monitoring and completed 2- and 3-dimensional examination. Two-dimensional left ventricular multilayer strain analysis was also performed. White-coat hypertension was diagnosed if clinical blood pressure was elevated and 24-hour blood pressure was normal. Our results showed that left ventricular longitudinal and circumferential strains gradually decreased from normotensive controls across subjects with white-coat hypertension to sustained hypertensive group. Two- and 3-dimensional left ventricular radial strain, as well as 3-dimensional area strain, was not different between groups. Two-dimensional left ventricular longitudinal and circumferential strains of subendocardial and mid-myocardial layers gradually decreased from normotensive control to sustained hypertensive group. Longitudinal and circumferential strains of subepicardial layer did not differ between the observed groups. We concluded that white-coat hypertension significantly affects left ventricular deformation assessed by 2-dimensional traditional strain, multilayer strain, and 3-dimensional strain.

Untreated Masked Hypertension and Subclinical Cardiac Damage: A Systematic Review and Meta-analysis

AIM

Data on the association of masked hypertension (MH) (i.e., normal office and elevated out-of-office blood pressure (BP)) with cardiac damage are scanty. We performed a meta-analysis in order to provide a comprehensive information on subclinical cardiac alterations in subjects with MH.

DESIGN

Studies were identified by the following search terms: "masked hypertension," "white coat normotension," "isolated ambulatory hypertension," "left ventricular mass," "left ventricular hypertrophy," "cardiac damage," and "echocardiography." Full articles published in English language providing data on left ventricular (LV) mass and/or prevalence of LV hypertrophy in MH, as assessed by ambulatory BP monitoring, were considered.

RESULTS

Overall, 4,884 untreated subjects (2,467 normotensive, 776 MH, and 1,641 sustained hypertensive individuals) of both genders included in 12 studies were analyzed. LV mass index showed a progressive increase from normotensive (79.2 ± 0.35 g/m(2)) to MH (91.6 ± 4.0 g/m(2)) (standard difference in means (SDM): 0.50 ± 0.11, confidence interval (CI): 0.28-0.73, P < 0.01) and to hypertensive subjects (102.9 ± 3.3g/m(2)) (SDM: 0.22 ± 0.07, CI: 0.09-0.35, P < 0.01). After assessing data for publication bias, the difference between groups was still significant.

CONCLUSIONS

Our findings support an association between MH and increased risk of LV structural alterations compared to true normotensive individuals. Due to the worse cardiovascular prognosis associated with subclinical cardiac damage, subjects with MH should be carefully screened in order to detect hypertensive organ damage and provide appropriate therapeutic interventions.