Gender-specific brachial artery blood pressure-independent relationship between pulse wave velocity and left ventricular mass index in a group of African ancestry

Pharmacological treatment of hypertension guided by peripheral or central blood pressure: a comparison between the two strategies

Background

Arterial hypertension treatment guided by central blood pressures (CPB) rather than peripheral blood pressures (PBP) measurement has the potential to show greater effectiveness in preventing or even regressing stiffness and target organ damage (TOD).

Objective

This study aimed to compare the parameters of CBP and PBP measurements, arterial stiffness, TOD and renal profile in patients with anti-hypertensive treatment guided by CBP or PBP targets.

Methods

A randomized clinical trial was conducted in central group (CG) and peripheral group (PG). Patients were randomized, evaluated every 3 months for BP and antihypertensive adjustments during a one-year follow up. The procedures in V1 and V5: anthropometric assessment; CBP/PBP measurements, carotid ultrasound; echocardiography; laboratory tests. Paired and unpaired t-tests and the χ2 were used (significance level: 5%).

Results

The study evaluated 59 participants (30CG/29PG). The augmentation index (AIx) was higher in the CG (27.3% vs. 20.3%, p = 0.041). Intergroup analysis has found central diastolic BP lower in the CG (78.9 vs. 84.3 mmHg, p = 0.024) and the Alx difference between groups ceased to exist after a one-year follow-up. Intragroup comparisons, after intervention, showed a lower frequency of changed PWV (p < 0.001) and LVMI (p = 0.018) in the CG. The PG showed a higher frequency of changed PWV (p < 0.001) and LVMI (p = 0.003).

Conclusion

The intervention guided by central BP reduced the central diastolic BP and AIx compared to the PG. There was a reduction in the frequency of changed PWV and LVMI in the CG.

Value of estimated pulse wave velocity to identify left ventricular hypertrophy prevalence: insights from a general population

Background

Aortic stiffness shares a similar profile of risk factors with left ventricular hypertrophy (LVH) and can also lead to LVH by itself. Published data have demonstrated the correlation between aortic stiffness and LVH. Recent data have revealed estimated pulse wave velocity (ePWV) to be a simple and cost-effective marker of the severity of aortic stiffness. Our analysis aimed to explore the association between ePWV and LVH prevalence, and to investigate the incremental value of ePWV for the identification of LVH prevalence.

Methods

The present analysis based on a cross-sectional survey which included 11,597 participants from rural areas of southeastern China between Sep 2020 and Feb 2021. ePWV was formulated based on mean blood pressure and age according to a published algorithm.

Results

The prevalence of LVH was 14.56%. With the adjustment of age, sex, education, income and physical activity level, current drinking and smoking status, BMI, waist circumference, serum creatinine, total cholesterol, high density cholesterol, mean blood pressure, fasting plasma glucose, anti-hypertensive therapy, anti-diabetic therapy, lipid-lowering therapy, and cardiovascular disease history, every standard deviation increment of ePWV associated with a 2.993 times risk of LVH prevalence. When dividing ePWV into quartiles, the top quartile had a 4.520 times risk of LVH prevalence when compared with the bottom quartile. Furthermore, smooth spline analysis displayed that the association was linear in the whole range of ePWV (p for non-linearity = 0.073). Additionally, subgroup analysis revealed the association was robust to sex, obesity and diabetes, and younger people and hypertensive population were more vulnerable to the increase of ePWV than their corresponding counterparts. Finally, ROC analysis showed a significant advancement when introducing ePWV into established risk factors (0.787 vs. 0.810, p for comparison < 0.001), and reclassification analysis also confirmed significant improvement from ePWV to identify LVH prevalence (category-free net reclassification analysis = 0.421, p < 0.001; integrated discrimination index = 0.023, p < 0.001).

Conclusion

Our analysis demonstrated a linear association between ePWV and LVH prevalence. Furthermore, our results suggest younger people and hypertensive population are more likely to have LVH prevalence with the increase of ePWV. More importantly, our findings implicate the incremental value of ePWV to optimize the identification of LVH prevalence in a general Chinese population.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-022-02541-9.

Renal physiology of glucose handling and therapeutic implications

The rationale for using sodium-glucose cotransporter 2 (SGLT2) inhibitors in patients with type 2 diabetes (T2D) has evolved over the last decade. Due to the effects on glucosuria and body weight loss, SGLT2 inhibitors were originally approved for glycemic control in T2D. Since glucosuria is attenuated in chronic kidney disease (CKD) Stages 3–5, initial regulatory approval for SGLT2 inhibitor use was limited to patients with T2D and preserved estimated glomerular filtration rate. Over time, however, it has become increasingly apparent that these therapies have a variety of important pharmacodynamic and clinical effects beyond glycemic lowering, including antihypertensive and antialbuminuric properties, and the ability to reduce glomerular hypertension. Importantly, these sodium-related effects are preserved across CKD stages, despite attenuated glycemic effects, which are lost at CKD Stage 4. With the completion of cardiovascular (CV) outcome safety trials—EMPA-REG OUTCOME, CANVAS Program and DECLARE TIMI-58—in addition to reductions in CV events, SGLT2 inhibition consistently reduces hard renal endpoints. Importantly, these CV and renal effects are independent of glycemic control. Subsequent data from the recent CREDENCE trial—the first dedicated renal protection trial with SGLT-2 inhibition—demonstrated renal and CV benefits in albuminuric T2D patients, pivotal results that have expanded the clinical importance of these therapies. Ongoing trials will ultimately determine whether SGLT2 inhibition will have a role in renal protection in other clinical settings, including nondiabetic CKD and type 1 diabetes.

Elevated exercise blood pressure in middle-aged women is associated with altered left ventricular and vascular stiffness

Women are at higher risk for developing heart failure with preserved ejection fraction (HFpEF). We examined the utility of peak exercise blood pressure (BP) in identifying preclinical features of HFpEF, namely vascular and cardiac stiffness in middle-aged women. We studied 47 healthy, nonobese middle-aged women (53 ± 5 yr). Oxygen uptake (V̇o₂) and BP were assessed at rest and maximal treadmill exercise. Resting cardiac function and stiffness were assessed by echocardiography and invasive measurement (right heart catheterization) of left ventricular (LV) filling pressure under varying preloads. LV stiffness was calculated by curve fit of the diastolic portion of the pressure-volume curve. Aortic pulse-wave velocity was measured by arterial tonometry. Body fat was measured using dual-energy X-ray absorptiometry. Subjects in the highest exercise BP tertile had peak systolic BP of 201 ± 11 compared with 142 ± 19 mmHg in the lowest tertile (P < 0.001). Higher exercise BP was associated with increased age, percentage body fat, smaller LV size, slower LV relaxation, and increased LV and vascular stiffness. After adjustment, LV and arterial stiffness remained significantly associated with peak exercise BP. There was a trend toward increased body fat and slowed LV relaxation (both P < 0.07). In otherwise healthy middle-aged women, elevated exercise BP was independently associated with increased vascular stiffness and a smaller, stiffer LV, functional and structural risk factors characteristic for stages A and B HFpEF.NEW & NOTEWORTHY Women are at increased risk for heart failure with preserved ejection fraction (HFpEF) largely due to higher prevalence of arterial and cardiac stiffening. We were able to identify several subclinical markers of early (stages A and B) HFpEF pathophysiology largely on the basis of exercise blood pressure (BP) response in otherwise healthy middle-aged women. Exercise BP response may be an inexpensive screening tool to identify women at highest risk for developing future HFpEF.

Arterial stiffness and hypertension status in Afro-Caribbean men

OBJECTIVE

African ancestry individuals are at high risk for hypertensive cardiovascular disease (CVD) and could benefit from early detection of arterial stiffening. We tested the association between the 2017 ACC/AHA hypertension categorizations, which include new blood pressure (BP) cutoffs and a definition for elevated BP, and arterial stiffness in 772 Afro-Caribbean men aged 50+ years (mean 64 years).

METHODS

Arterial stiffness was assessed by brachial-ankle pulse-wave velocity (PWV) using a waveform analyzer. Hypertension groups were based on the 2017 ACC/AHA guidelines and by pharmacologic control status. Multiple linear/logistic regression was used to determine the association of PWV with BP and hypertension.

RESULTS

Mean (SD) PWV was 1609 (298) cm/s and was independently correlated with age, SBP, pulse, diabetes, height, and alcohol intake (all P < 0.02). After adjusting for these, in men aged at least 65 years, those with stage 1 or uncontrolled stage 2 hypertension had significantly greater PWV than all other groups (all P < 0.05). Men with controlled hypertension had similar PWV to those with elevated BP (P = 0.7); however, this was significantly greater than men with normal BP (all P < 0.05). Patterns were similar, but with smaller effect sizes, in men aged less than 65 years (all P < 0.05 except controlled hypertension versus elevated or normal BP were not significant).

CONCLUSION

In these high-risk Afro-Caribbeans: stage 1 hypertension is associated with increased PWV, which supports the new guidelines; and, pharmacologic control appears to partially protect men from increased PWV. Longitudinal studies are needed to determine optimal PWV and timing of antihypertensive treatment for preventing future CVD.

IMPACT OF BLOOD PRESSURE COMPONENTS ON LEFT VENTRICULAR HYPERTROPHY REMODELING

SUMMARY – According to present findings, the impact of particular arterial pressure components on the occurrence of left ventricular hypertrophy (LVH) differs. We sought to determine which individual component of arterial pressure has the greatest impact on the LVH geometric pattern/degree. The study included 192 patients (87 men), aged 43-80 (median 68) years with hypertension and LVH. Patients were classified into three groups according to type of hypertrophy (concentric, eccentric and asymmetric) and into three subgroups according to the degree of hypertrophy (mild, moderate and severe). All patients had their blood pressure measured, and they underwent electrocardiography and echocardiography. Antihypertensive drugs and the duration of previous treatments were taken into consideration. Pulse pressure was significantly higher in patients with concentric LVH than in those with eccentric and asymmetric LVH (p=0.029), the values of which did not differ statistically. It rose with LVH degree (not significantly, p=0.217). There were no significant differences in systolic pressure among study groups (p=0.177). We concluded that pulse pressure had the greatest impact on the left ventricular geometry, particularly of the concentric type.

The risk of hypertension and cardiovascular disease in women with uterine fibroids

Women with fibroids have a notably high hypertension risk. However, adjusted data regarding other cardiovascular disease (CVD) risk factors are scarce. In this cross-sectional study, CVD risk factors, hemodynamic parameters, and asymptomatic organ damage were analyzed between women with uterine fibroids and controls in a multi-ethnic population. In total, 104 women with self-reported fibroids and 624 controls were included. Women with fibroids had significantly higher odds to have hypertension (OR 3.4; 95% CI 2.2-5.2), diabetes (1.7; 1.0-2.9), and hypercholesterolemia (1.8; 1.1-3.2). After adjustment for confounders, only the odds ratio for hypertension was significant (1.8; 1.1-3.1). Asymptomatic organ damage occurred significantly more often in women with fibroids (66.7%; 95% CI 55.8%-77.6% vs 42.9%; 38.0-47.8 in controls), especially in the younger age group (respectively 48.5%; 31.1%-65.9% vs 22.1%; 17.0-27.2). In this study, women with fibroids had a remarkably high hypertension risk compared to controls, with more asymptomatic organ damage, in particular young women.

Accuracy of non-invasive blood pressure measurements in obese patients

This article describes an evidence-based literature review, comparing upper arm and forearm blood pressure measurements using non-invasive devices on obese patients. The focus on blood pressure monitoring was in response to regularly witnessing inappropriately applied blood pressure cuffs on obese patient's upper arms in practice. An inaccurately obtained blood pressure measurement can result in the misdiagnosis and treatment of hypertension. As the prevalence of obesity grows worldwide, healthcare settings need to ensure they have the necessary equipment and trained staff to accurately measure obese patients' blood pressure. The aim of this review was to identify whether a forearm measurement provided a suitable alternative to upper arm measurements. The article discusses the development and execution of a search strategy, as well as the critical appraisal of a selected article. The results of the review demonstrated that forearm blood pressure measurements in obese patients do not replace upper arm blood pressure measurements taken with an appropriate cuff. It is recommended that further research is undertaken in order to identify suitable alternatives for obtaining an accurate non-invasive blood pressure measurement in obese patients.

Association of Blood Pressure Variability Ratio With Glomerular Filtration Rate Independent of Blood Pressure and Pulse Wave Velocity

BACKGROUND

Blood pressure variability ratio (BPVR)(derived from within-subject SD of 24-hour ambulatory blood pressure [BP]) predicts all-cause mortality independent of BP and has a similar prognostic ability to ambulatory arterial stiffness (AASI). Whether BPVR, and AASI, offer prognostic information beyond measurements of arterial stiffness at a given pressure, as indexed by pulse wave velocity (PWV), is not known.

METHODS

We assessed whether BPVR and AASI were associated with indices of subclinical organ damage (TOD) [estimated glomerular filtration rate (eGFR), left ventricular mass index, early-to-late transmitral velocity (E/A), carotid intima-media thickness (IMT)] independent of BP, and whether BPVR-TOD and AASI-TOD relations were independent of PWV (applanation tonometry) in 772 randomly selected participants from an urban, developing community. AASI was derived from 24-hour diastolic BP vs. systolic BP standard linear regression.

RESULTS

On bivariate analyses, BPVR, AASI, and PWV were correlated with all indices of TOD (P < 0.0005). However, after adjustments for potential confounders including age and 24-hour mean BP, BPVR, and PWV (P < 0.005 to P < 0.0001), but not AASI (P > 0.25), were independently associated with eGFR, but not other indices of TOD. Importantly, the BPVR-eGFR relation was independent of BP variability (P < 0.005) and PWV (P < 0.001).

CONCLUSIONS

BPVR was negatively associated with eGFR independent of mean BP, BP variability, and PWV. Therefore, in the prediction of cardiovascular risk, measurements of arterial stiffening (BPVR) may provide information beyond the impact of arterial stiffness.

Carotid and aortic stiffness in essential hypertension and their relation with target organ damage: the CATOD study

OBJECTIVE

The objective of the study is to investigate in the hypertensive population the possible differential association between increased aortic and/or carotid stiffness and organ damage in multiple districts, such as the kidney, the vessels, and the heart.

METHODS

In 314 essential hypertensive patients, carotid-femoral pulse wave velocity (cfPWV, by applanation tonometry) and carotid stiffness (from ultrasound images analysis), together with left ventricular hypertrophy, carotid intima-media thickness, urinary albumin-creatinin ratio, and glomerular filtration rate were measured. Increased cfPWV and carotid stiffness were defined according to either international reference values or the 90th percentile of a local control group (110 age and sex-matched healthy individuals).

RESULTS

When considering the 90th percentile of a local control group, increased cfPWV was associated with reduced glomerular filtration rate, either when carotid stiffness was increased [odds ratio (OR) 13.27 (confidence limits (CL) 95% 3.86-45.58)] or not [OR 7.39 (CL95% 2.25-24.28)], whereas increased carotid stiffness was associated with left ventricular hypertrophy, either when cfPWV was increased [OR 2.86 (CL95% 1.15-7.09)] or not [OR 2.81 (CL95% 1.13-6.97)]. No association between increased cfPWV or carotid stiffness and target organ damage was found when cutoffs obtained by international reference values were used. The concomitance of both increased cfPWV and carotid stiffness did not have an additive effect on organ damage.

CONCLUSION

Aortic and carotid stiffness are differentially associated with target organ damage in hypertensive patients. Regional arterial stiffness as assessed by cfPWV is associated with renal organ damage and local carotid stiffness with cardiac organ damage.

Contributions of aortic pulse wave velocity and backward wave pressure to variations in left ventricular mass are independent of each other

Aortic pulse wave velocity (PWV) and backward waves, as determined from wave separation analysis, predict cardiovascular events beyond brachial blood pressure. However, the extent to which these aortic hemodynamic variables contribute independent of each other is uncertain. In 749 randomly selected participants of African ancestry, we therefore assessed the extent to which relationships between aortic PWV or backward wave pressures (Pb) (and hence central aortic pulse pressure [PPc]) and left ventricular mass index (LVMI) occur independent of each other. Aortic PWV, PPc, forward wave pressure (Pf), and Pb were determined using radial applanation tonometry and SphygmoCor software and LVMI using echocardiography; 44.5% of participants had an increased left ventricular mass indexed to height^1.7. With adjustments for age, brachial systolic blood pressure or PP, and additional confounders, PPc and Pb, but not Pf, were independently related to LVMI and left ventricular hypertrophy (LVH) in both men and women. However, PWV was independently associated with LVMI in women (partial r = 0.16, P < .001), but not in men (partial r = 0.03), and PWV was independently associated with LVH in women (P < .05), but not in men (P = .07). With PWV and Pb included in the same multivariate regression models, PWV (partial r = 0.14, P < .005) and Pb (partial r = 0.10, P < .05) contributed to a similar extent to variations in LVMI in women. In addition, with PWV and Pb included in the same multivariate regression models, PWV (P < .05) and Pb (P < .02) contributed to LVH in women. In conclusion, aortic PWV and Pb (and hence pulse pressure) although both associated with LVMI and LVH produce effects which are independent of each other.

Prevalence of arterial stiffness and the risk of myocardial diastolic dysfunction in women

The present study reports markers of vascular function among a general female population and shows that left ventricular diastolic dysfunction (LVDD) is significantly associated with pathological PWV (⩾9.7 m/s), a waist circumference >80 cm and age.

The present study determines the prevalence of vascular dysfunction and arterial stiffness (ASt) in a female urban population by measuring the brachial augmentation index (AIx) and aortic pulse wave velocity (PWV). The study tests the hypothesis that the measurement of AIx and PWV is useful in addition to that of traditional cardiovascular risk factors when assessing the risk for left ventricular diastolic dysfunction (LVDD). This cross-sectional study recruited 965 women aged 25–75 years from 12 districts of Berlin. The ASt indices, brachial AIx, aortic PWV and the central blood pressure were measured by an oscillometric method. A randomly selected subgroup (n=343) was examined by echocardiography. Trans-mitral inflow E/A ratio and diastolic mitral annulus velocity (é) were assessed. Questionnaires, medical history and blood sampling were used for the evaluation of individual risk factors. Normal vascular function was found in 55% of the women included. The prevalence of women with pathological AIx only (AIx ⩾ −10%, PWV normal) was 21.5%, whereas 17.9% were affected by increased AIx and PWV (AIx ⩾ −10%, PWV ⩾9.7 m/s), and 6% with only pathological PWV values. The prevalence of LVDD was 31.7%. LVDD was significantly associated with pathological PWV ⩾ 9.7 m/s [OR: 1.27, 95%CI: 1.02–1.57], age [OR: 4.17, 95%CI: 2.87–6.07] and a waist circumference >80 cm [OR: 3.61, 95%CI: 1.85–7.04] in multiple regression analysis. The high prevalence of markers for vascular dysfunction and ASt in a general female population and their importance as a mediator of diastolic dysfunction should encourage implementation of aortic PWV measurement to improve cardiovascular-risk assessment in particular to identify subclinical myocardial diastolic dysfunction.

Cardio-ankle vascular index and subclinical heart disease

The relationship between arterial stiffness, measured as pulse wave velocity (PWV), and the left ventricle is confounded by the effects of blood pressure. We evaluated the relationship between carotid-femoral PWV and cardio-ankle vascular index (CAVI), a less pressure-dependent measurement of the stiffness constant (β) of the aorta and the iliac, femoral and tibial arteries, and obtained prognostically relevant measurements of left ventricular structure and systolic function. CAVI, carotid-femoral PWV and echocardiographic left ventricular mass and systolic function were determined in 133 subjects with either hypertension or high-normal blood pressure (33% treated; 56 ± 16 years, blood pressure 145/89 ± 21/12 mm Hg). Carotid-femoral PWV exhibited a direct relationship with systolic and diastolic blood pressure (r = 0.33/0.26, P < 0.001/0.014), whereas CAVI demonstrated no such relationship (r = 0.12/-0.05, both P > 0.1). Both CAVI and PWV correlated significantly with left ventricular mass index (r = 0.31, P<0.001; r = 0.21, P = 0.014). Subjects with inappropriately high left ventricular masses for a given cardiac workload (n = 44) had higher CAVI values (9.1 ± 2.0 vs. 7.9 ± 1.6, P < 0.001), but not higher PWV values (8.5 ± 2.5 vs. 8.7 ± 2.4, P>0.1). In a multivariate regression model, CAVI was independently associated with inappropriate left ventricular mass (β = 0.40, P < 0.001), along with body mass index. CAVI also demonstrated a negative relationship with left ventricular midwall fractional shortening (r = -0.41, P = 0.001) that was independent of age, sex, blood pressure and left ventricular mass in a multivariate analysis. In conclusion, a high CAVI is associated with inappropriately high left ventricular mass and low midwall systolic function. As a marker of arterial diastolic-to-systolic stiffening, CAVI may have a relationship with left ventricular structure and function that is independent of blood pressure levels.

Gender, clamped hyperglycemia and arterial stiffness in patients with uncomplicated type 1 diabetes mellitus

BACKGROUND

Diabetes mellitus (DM) reduces female gender-mediated protection against the development of renal disease possibly through effects on hyperglycemia. Women with DM also exhibit increased arterial stiffness, which may promote renal disease progression. The mechanisms responsible for increased arterial stiffness in women and the possible role of acute changes in ambient glycemia remain unknown.

METHODS

Blood pressure, augmentation index (AIx), pulse wave velocity (PWV) and circulating mediators of the renin angiotensin system and nitric oxide (cGMP) were measured in men (n = 22) and women (n = 19) with uncomplicated type 1 DM under clamped euglycemic and hyperglycemic conditions.

RESULTS

At baseline, men exhibited higher levels of angiotensin II (p = 0.030) and lower cGMP levels (p = 0.004), higher systolic blood pressure (124 ± 2 versus 109 ± 2 mmHg, p < 0.0001) and pulse pressure (42 ± 2 versus 58 ± 2 beats per minute, p < 0.0001). For arterial stiffness, radial (-8.0 ± 2.6% versus +5.4 ± 3.7%, p < 0.0001) and carotid AIx (-4.7 ± 2.9 versus +12.5 ± 3.0, p < 0.0001) were lower in men versus women. In contrast, carotid-femoral PWV was similar in men and women (5.20 ± 0.30 versus 5.13 ± 0.17, respectively, p = 0.853). In response to clamped hyperglycemia, systolic blood pressure increased in women (109 ± 2 to 112 ± 2 mmHg, p = 0.005) but not men. Serum aldosterone increased and cGMP declined in women but not in men. Clamped hyperglycemia did not influence arterial stiffness in either group and radial and carotid AIx remained higher in women.

CONCLUSIONS

Arterial stiffness is higher in women with type 1 DM. This effect is not dependent on the effects of clamped hyperglycemia or neurohormonal activation.

Cardiac structure and function in relation to central blood pressure components in Chinese

BACKGROUND

Data are limited with regard to the association of central blood pressure (BP) components with cardiac structure and function.

METHODS

Our study was conducted in the framework of cardiovascular health examinations for the current and retired employees of a factory and their family members. We measured central BP by SphygmoCor and cardiac structure and function by echocardiography.

RESULTS

The 826 participants (mean age 43.0 years) included 285 (34.5%) women and 184 (22.3%) hypertensive patients, of whom 78 (42.4%) took antihypertensive drugs. After adjustment for age, sex, body weight, body height, antihypertensive treatment, current smoking and alcohol intake, left atrial volume and left ventricular mass were significantly associated with brachial and central BP components (r = 0.09-0.21, P ≤ 0.01), whereas left ventricular diastolic dysfunction, evaluated by E/A ratio and deceleration time of E wave (DTE), was only significantly associated with brachial and central SBP (r = 0.14-0.18, P < 0.001). However, these correlation coefficients were quantitatively but nonsignificantly different between brachial and central BP (P ≥ 0.06). In regression models with similar adjustments, with 1-SD increase in central SBP (16.7 mmHg), E/A ratio significantly decreased by 5.5 ± 1.2% and DTE significantly increased by 4.66 ± 1.22 ms (P < 0.001). Sensitivity analyses in men and women separately and after exclusion of patients on antihypertensive medication were confirmatory.

CONCLUSION

Cardiac structure was significantly and comparably associated with central BP components, but left ventricular diastolic dysfunction was only significantly associated with central SBP.

Correlation of pulse wave velocity with left ventricular mass in patients with hypertension once blood pressure has been normalized

Vascular stiffness has been proposed as a simple method to assess arterial loading conditions of the heart which induce left ventricular hypertrophy (LVH). There is some controversy as to whether the relationship of vascular stiffness to LVH is independent of blood pressure, and which measurement of arterial stiffness, augmentation index (AI) or pulse wave velocity (PWV) is best. Carotid pulse wave contor and pulse wave velocity of patients (n=20) with hypertension whose blood pressure (BP) was under control (<140/90 mmHg) with antihypertensive drug treatment medications, and without valvular heart disease, were measured. Left ventricular mass, calculated from 2D echocardiogram, was adjusted for body size using two different methods: body surface area and height. There was a significant (P<0.05) linear correlation between LV mass index and pulse wave velocity. This was not explained by BP level or lower LV mass in women, as there was no significant difference in PWV according to gender (1140.1+67.8 vs 1110.6+57.7 cm/s). In contrast to PWV, there was no significant correlation between LV mass and AI. In summary, these data suggest that aortic vascular stiffness is an indicator of LV mass even when blood pressure is controlled to less than 140/90 mmHg in hypertensive patients. The data further suggest that PWV is a better proxy or surrogate marker for LV mass than AI and the measurement of PWV may be useful as a rapid and less expensive assessment of the presence of LVH in this patient population.

Global cardiovascular risk profiles of untreated hypertensives in an urban, developing community in Africa

Introduction

Blood pressure (BP) control in people of African descent is poor, largely because of a lack of treatment. Although the requirements for immediate initiation of antihypertensive drug therapy are defined by global cardiovascular risk, the global cardiovascular risk profiles of untreated hypertensives at a community level are uncertain.

Aim

To identify the distribution of global cardiovascular risk profiles of untreated hypertensives in an urban, developing community of African descent in South Africa.

Methods

As part of the African Programme on Genes in Hypertension, we assessed nurse-derived clinic BP (the mean of five standardised BP values obtained according to guidelines), current antihypertensive therapy, and total cardiovascular risk in 1 029 participants older than 16 years of age from randomly selected nuclear families from the South West Township of Gauteng (SOWETO).

Results

Approximately 46% of participants had systolic/diastolic BP values ≥ 140/90 mmHg and ~23% of participants were hypertensives not receiving antihypertensive medication. Approximately 12% of untreated hypertensives had a high added risk and ~18% a very high added risk (6.7% of the total sample). In untreated hypertensives, in contrast to the absence of severe hypertension and diabetes mellitus in those with lower risk profiles, a high cardiovascular risk profile in this group was characterised by severe hypertension in ~52% and diabetes mellitus in ~33%. Based on a high added risk carrying at least a 20% chance and a very high added risk at least a 30% chance of a cardiovascular event in 10 years, this translates into 1 740 events per 100 000 of the population within 10 years, events that could be prevented through antihypertensive drug therapy.

Conclusions

In an urban, developing community of African ancestry, a significant proportion (6.7%) of people may have untreated hypertension and a global cardiovascular risk profile that suggests a need for antihypertensive drug therapy. Cardiovascular risk in this group is driven largely by the presence of severe hypertension or diabetes mellitus.

Aortic elastic properties in nonalcoholic fatty liver disease

BACKGROUND

Recent studies have shown that patients with nonalcoholic fatty liver disease (NAFLD) have an increased risk of developing cardiovascular disease. Aortic stiffness, an early marker of arteriosclerosis, is associated with cardiovascular mortality. In this study, the aortic elastic properties of nondiabetic, normotensive NAFLD patients were evaluated.

METHODS

Thirty-five patients with NAFLD and 30 age-matched and sex-matched healthy controls were enrolled. Aortic distensibility, aortic strain, aortic stiffness index (ASI), left ventricular mass index (LVMI), homeostasis model assessment of insulin resistance (HOMA-IR) and fasting lipid parameters were assessed in both the groups.

RESULTS

ASI was higher in NAFLD patients (7.1+/-2.0) than in the control group (3.8+/-1.0) (P<0.01). Aortic distensibility and aortic strain were also significantly decreased in NAFLD patients as compared with the control group (2.9+/-0.7 cm/dyn vs. 6.3+/-2.4 cm/dyn, P<0.0001 and 7.1+/-1.7 vs. 14.5+/-4.0, P<0.0001, respectively). Although ASI was significantly correlated with age, HOMA-IR, waist circumference, body mass index and LVMI, a stepwise multiple linear regression analysis showed that HOMA-IR and LVMI were the only variables associated with ASI index [(standardized beta coefficient= 0.41, P=0.004, overall R=0.17) and (standardized beta coefficient=0.31, P=0.02, overall R=0.10), respectively].

CONCLUSION

Our data suggest that aortic elasticity is significantly impaired and is also associated with insulin resistance and LVMI in NAFLD patients, which may contribute to the relationship between NAFLD and the increased risk of cardiovascular disease among these patients.

Contribution of central and general adiposity to abnormal left ventricular diastolic function in a community sample with a high prevalence of obesity

The relative independent contribution of excess adiposity, as indexed by measures of central, general, or peripheral adiposity, toward abnormal cardiac diastolic chamber function at a community level is unclear. In 377 randomly selected participants >16 years old from a community sample with a high prevalence of excess adiposity ( approximately 25% overweight and approximately 43% obese), we assessed the independent contribution of the indexes of adiposity to the variation in early-to-late (atrial) transmitral velocity (E/A). After adjustments for a number of confounders, including age, gender, pulse rate, conventional diastolic (or systolic) blood pressure, antihypertensive treatment, left ventricular mass index, and the presence of diabetes mellitus or a hemoglobin A1c level >6.1%; waist circumference was an independent predictor of a reduced E/A (p = 0.0038). Body mass index (p = 0.07), waist-to-hip ratio (p = 0.23), and skinfold thickness (p = 0.37) were not independently associated with E/A, whereas waist circumference was independently associated with E/A, even after adjustments for other adiposity indexes, including body mass index (p <0.05 to 0.005). In contrast to the effects on diastolic function, the waist circumference did not correlate with the left ventricular ejection fraction (p = 0.23). The independent relation between the waist circumference and E/A (standardized beta coefficient -0.14 +/- 0.05, p = 0.0038) was second only to age (standardized beta coefficient -0.57 +/- 0.05, p <0.0001) and similar to blood pressure (standardized beta coefficient -0.11 +/- 0.04, p = 0.0075) in the magnitude of the independent effect on E/A. The inclusion of the relative wall thickness rather than the left ventricular mass index in the regression equation produced similar outcomes. The exclusion of the left ventricular mass index and relative wall thickness from the regression equations or the inclusion of carotid-femoral pulse wave velocity or 24-hour blood pressure as confounders failed to modify the relation between waist circumference and E/A. In conclusion, the waist circumference was second only to age in the impact on an independent association with E/A in a population sample with a high prevalence of excess adiposity. This effect was not accounted for by left ventricular hypertrophy or remodeling, the 24-hour blood pressure, or arterial stiffness.