Masked Hypertension and Left Atrial Dysfunction: A Hidden Association

Hypertensive Heart Disease: A Narrative Review Series-Part 2: Macrostructural and Functional Abnormalities

Hypertensive heart disease (HHD) remains a major global public health concern despite the implementation of new approaches for the management of hypertensive patients. The pathological changes occurring during HHD are complex and involve the development of structural and functional cardiac abnormalities. HHD describes a broad spectrum ranging from uncontrolled hypertension and asymptomatic left ventricular hypertrophy (LVH), either a concentric or an eccentric pattern, to the final development of clinical heart failure. Pressure-overload-induced LVH is recognised as the most important predictor of heart failure and sudden death and is associated with an increased risk of cardiac arrhythmias. Cardiac arrhythmias are considered to be one of the most important comorbidities affecting hypertensive patients. This is the second part of a three-part set of review articles. Here, we focus on the macrostructural and functional abnormalities associated with chronic high pressure, their involvement in HHD pathophysiology, and their role in the progression and prognosis of HHD.

Effects of Nondipping Blood Pressure Changes: A Nephrologist Prospect

Blood pressure (BP) variations depend on various internal, environmental, and behavioral factors. BP fluctuations occur both in normotensive and hypertensive people. Although it fluctuates over the 24-hr day and night, the morning BP increases after waking up and declines throughout sleep. It is typical for BP to decrease by 10% to 20%, while sleeping, known as dipping BP. However, if there is no decrease in nighttime mean systolic BP or a drop of less than 10 mmHg, it is called nondipping BP. Conversely, reverse dipping BP means an increase in mean systolic BP instead of a drop during the night. Reverse dipping is observed in hypertension (HTN), diabetes mellitus (DM), chronic kidney disease (CKD), and obstructive sleep apnea (OSA) syndrome. The introduction of ambulatory BP monitoring (ABPM) led to the emergence of identifying normal and elevated BP patterns. Non-dipping BP increases the risk of cardiovascular system (CVS) complications such as left ventricular hypertrophy, proteinuria, glomerular filtration rate (GFR) reduction, and CKD progression. A loss or blunting of the normal BP profile is recognized as a deleterious variant, and restoring abnormal BP patterns has been reported to significantly impact end-organ damage, morbidity, and mortality. In this non-systematic clinically-oriented, comprehensive review, we aim to update the BP variables and the pathophysiology of nondipping BP and point out the areas which need more investigation from a nephrology perspective because the nondipping BP increases the risk of proteinuria, GFR reduction, and CKD progression. A literature search of PubMed, Google, EMBASE, and Google Scholar was conducted. Checks of selected papers and relevant reviews complemented the electronic search. With improved BP measurement methods, the physiology of BP profile variations is readily detectable during the day and night. A nondipping BP profile is a distinct BP pattern that may have significant end-organ damage effects and therapeutic importance for nephrologists. The pathophysiology of the nondipping BP variant must be clarified to prevent complications, and further investigations are required. Furthermore, there is debate about the best BP index to utilize: systolic BP, diastolic BP, mean arterial pressure, or a mixture of all. All these areas are important and need new research projects.

The prevalence of masked hypertension in patients with lone atrial fibrillation: a cross sectional analytical study

Atrial fibrillation (AF) is prevalent in individuals with essential hypertension (HTN). Masked hypertension occurs in up to 15% of the general population and is associated with adverse clinical outcome. The aim of the current study was to evaluate the prevalence of masked hypertension in apparently normotensive individuals with lone AF. A cross sectional analytical study performed at the Rabin Medical Center included all patients > 18 years who visited the emergency department (ED) in the years 2018-2021 with idiopathic AF, had normal blood pressure (BP) values during their ED visit and did not have a history of hypertension or current use of anti-hypertensives. Ambulatory blood pressure monitoring (ABPM) was performed in all eligible patients within 30 days from ED visit. Data collected included information from the ED visit and data extracted from the monitoring device. A total of 1258 patients were screened for eligibility, of which 40 were included in the analysis. The average age was 53.4 ± 16 years, 28 patients (70%) were males. Overall, 18 individuals (46%) had abnormal BP values according to the 2017 ACC/AHA guidelines for the diagnosis of hypertension. Of these, 12 had abnormal 24-h BP average (≥ 125/75 mmHg), one had isolated daytime abnormal average (≥ 130/80 mmHg) and 11 had isolated night time abnormal average (≥ 110/65 mmHg). Masked hypertension is prevalent in patients with lone AF without a diagnosis of HTN and performing ABPM in such individuals should be strongly considered.

Unmasking left ventricular systolic dysfunction in masked hypertension: looking at myocardial strain. A review and meta-analysis

BACKGROUND AND AIM

A growing body of evidence supports the view that masked hypertension (MH) (i.e. normal office and elevated out-of-office BP) is a blood pressure (BP) phenotype associated with increased risk of subclinical organ damage, cardiovascular disease and death as compared to true normotension. Whether left ventricular (LV) systolic function is impaired in individuals with MH is still a poorly defined topic. Therefore, we aimed to provide a new piece of information on LV systolic dysfunction in the untreated MH setting, focusing on speckle tracking echocardiography (STE) studies investigating LV global longitudinal strain (GLS), a more sensitive index of systolic function than conventional LV ejection fraction (LVEF).

METHODS

A computerized search was performed using Pub-Med, OVID, EMBASE and Cochrane library databases from inception until June 30, 2022. Full articles reporting data on LV GLS in MH, as assessed by ambulatory BP monitoring (ABPM), and normotensive controls were considered suitable for the purposes of review and meta-analysis.

RESULTS

A total of 329 untreated individuals with MH and 376 normotensive controls were included in six studies. While pooled average LVEF was not different between groups [64.5 ± 1.5 and 64.5 ± 1.3%, respectively, standard means difference (SMD): -0.002 ± 0.08, confidence interval (CI): 0.15/-0.15, P = 0.98), LV GLS was worse in MH patients than in normotensive counterparts (-18.5 ± 0.70 vs. -20.0 ± 0.34%, SMD: 0.68 ± 0.28, CI: 0.12/1.24, P < 0.01).

CONCLUSIONS

Our findings suggest that early changes in LV systolic function not detectable by conventional echocardiography in the MH setting can be unmasked by STE and that its implementation of STE in current practice may improve the detection of subclinical organ damage of adverse prognostic significance.

Left Ventricular Measurements and Strain in Pediatric Patients Evaluated for Systemic Hypertension and the Effect of Adequate Anti-hypertensive Treatment

Pediatric hypertension (HTN) is an epidemic that is associated with HTN in adulthood and adverse cardiovascular outcomes. We hypothesized that children with HTN would have left ventricular (LV) hypertrophy and abnormal LV global longitudinal strain (GLS) on echocardiogram and that these values would differ by weight, race, and HTN treatment. Data were collected from first visits to the HTN Program from 12/2011 to 9/2018, excluding patients with cardiac disease or heart transplantation. LV measurements including LV mass index (LVMI), LV GLS, and diastolic indices were compared between groups. Multivariable logistic regression was used to identify risk factors for an abnormal LVMI. There were 212 patients with an interquartile age range of 13-18 years. On univariate analysis, LVMI was higher in hypertensive, obese, and African American patients. LV strain was less negative in obese and African American patients. Adequately treated patients with HTN had a higher LVMI and a higher E/e' ratio compared to patients with no HTN. On multivariate analysis, only obesity was associated with an LVMI ≥ 95th percentile (OR 2.9, 95% CI 1.4, 5.8). LVMI is higher in hypertensive, obese, and African American patients; however, in the multivariate analysis, obesity was the only independent risk factor for an abnormal LVMI. LVMI was still higher in those adequately treated for HTN compared to patients without HTN, possibly due to concomitant obesity. Future studies should focus on subclinical changes in LV performance seen in obese and hypertensive patients and the impact on long-term health.

Association of Anemia and Blood Pressure With Novel Markers of Diastolic Function in Pediatric Sickle Cell Disease

Diastolic dysfunction is a known cause of mortality in adults with sickle cell disease (SCD). Left atrial function (LAf) and strain (LAS) are novel echocardiographic parameters to assess early diastolic dysfunction, which have not been assessed in pediatric SCD. Through a retrospective single-center study, we describe echocardiographic parameters of diastology in children with SCD and evaluate their relationship with clinical variables including anemia and blood pressure. Baseline clinical data, 24-hour ambulatory blood pressure monitoring data and echocardiography results were collected. LAf and LAS were measured using volumetric data and speckle-tracking echocardiography, respectively. Sixty-seven children with SCD (13.5±7 y, 47% male, 7% hypertensive) with a mean hemoglobin of 8.8±1.3 g/dL, LAf of 61±8% (n=53) and LAS of 46.3±7.4% (n=28) were included. LAS was significantly associated with hemoglobin (ρ=0.43, P=0.022) but not with maximal left atrial (LA) volume (ρ=-0.05, P=0.79) or any blood pressure parameters. On multivariate analysis, LAS decreased by 3.2% (1.3, 5.1) and LA volume increased by 1.6 mL/m2 (3.1, 0.08) for every 1 g/dL decrease in hemoglobin. Thus, severity of baseline anemia in pediatric SCD correlates with diastolic function as measured by LAS, independent of LA dilation.

Which is responsible for target organ damage in masked hypertension? Is it an increase in blood pressure or a disruption of the circadian rhythm?

OBJECTIVE

Masked hypertension (MH) and non-dipping pattern are conditions associated with target organ damage and cardiovascular risk, which are frequently observed together. We aimed to show the relationship between the target organ damage observed in MH and the deterioration in the dipping pattern.

METHODS

Patients who underwent ambulatory blood pressure monitoring (ABPM) and office blood pressure (BP) <140/90 mmHg were retrospectively screened. In ABPM data, those with daytime BP ≥135/85 mmHg and night BP ≥120/70 mmHg were included in the MH group, while the others were included in the normotensive group. The patients were grouped as dipper, non-dipper and reverse-dipper according to ABPM results. Left ventricular mass index (LVMI), glomerular filtration rate (GFR) and serum creatinine levels were used to determine target organ damage.

RESULTS

289 patients [mean age 46.6 ± 12.4 years, 136 (47.1%) males], 154 (53.3%) of whom had MH were included in our study. GFR value was found to be significantly lower, serum creatinine levels and LVMI were significantly higher in patients with MH compared to normotensives (p < .05, for all). When the subgroups were examined, it was found that this difference was associated with the disruption in the dipping pattern. In patients with MH, dipping pattern disruption without change in systolic BP was independently associated with an increase in LVMI (p < .05, for both).

CONCLUSION

Target organ damage seen in MH may be due to the deterioration of the dipping pattern.

Left ventricular hypertrophy in athletes: How to differentiate between hypertensive heart disease and athlete’s heart

Athlete’s heart is typically accompanied by a remodelling of the cardiac chambers induced by exercise. However, although competitive athletes are commonly considered healthy, they can be affected by cardiac disorders characterised by an increase in left ventricular mass and wall thickness, such as hypertension. Unfortunately, training-induced increase in left ventricular mass, wall thickness, and atrial and ventricular dilatation observed in competitive athletes may mimic the pathological remodelling of pathological hypertrophy. As a consequence, distinguishing between athlete’s heart and hypertension can sometimes be challenging. The present review aimed to focus on the differential diagnosis between hypertensive heart disease and athlete’s heart, providing clinical information useful to distinguish between physiological and pathological remodelling.

Predictors and Consequences of Pediatric Hypertension: Have Advanced Echocardiography and Vascular Testing Arrived?

PURPOSE OF REVIEW

Pediatric hypertension is relatively common and associated with future adult hypertension. Elevated blood pressure in youth predicts future adult cardiovascular disease and blood pressure control can prevent progression of pediatric kidney disease. However, pediatric blood pressure is highly variable within a given child and among children in a population.

RECENT FINDINGS

Therefore, modalities to index aggregate and cumulative blood pressure status are of potential benefit in identifying youth in danger of progression from a risk factor of subclinical phenotypic alteration to clinically apparent event. In this review, we advocate for the health risk stratification roles of echocardiographically assessed cardiac remodeling, arterial stiffness assessment, and assessment by ultrasound of arterial thickening in children and adolescents with hypertension.

Clinical and prognostic significance of a reverse dipping pattern on ambulatory monitoring: An updated review

Reverse or inverted dipping (ie, the phenomenon characterized by higher nighttime compared with daytime blood pressure values) is an alteration of circadian blood pressure rhythm frequently documented in hypertension, type 2 diabetes mellitus, chronic kidney disease, and sleep apnea syndrome, and generally regarded as a harmful condition. Available literature on the clinical and prognostic implications of reverse dipping is scanty. The present article will review a number of relevant issues concerning reverse dipping, in particular: (1) its possible mechanisms; (2) prevalence and clinical correlates, (3) concomitant cardiac and extracardiac subclinical organ damage; (4) association with acute and chronic cardiovascular diseases; (5) prognostic value in predicting cardiovascular events and mortality; and (6) therapeutic interventions aimed at reverting this abnormal circadian blood pressure rhythm.