Cardio-ankle vascular index is independently associated with the severity of coronary atherosclerosis and left ventricular function in patients with ischemic heart disease

Identifying the high-benefit population for weight management-based cardiovascular disease prevention in Japan

Background

Cardiovascular-disease (CVD) is the leading cause of death, and the association between obesity and CVD is particularly significant among women. Given the evidence highlighting the significance of weight-gain velosity, we aimed to elucidate its influence on cardio-ankle vascular index (CAVI), a reliable surrogate marker of CVD, and identify the high-benefit population where this influence is most pronounced.

Methods

This multicenter retrospective study used electronic data from annual health checkups for workers in Japan. Individuals who voluntarily measured CAVI in 2019 were included, and weight-gain velosity was defined as the mean BMI gain from 2015 to 2019. Our primary outcome was the relationship between weight-gain velosity and CAVI.

Results

Among 459 individuals, 53 had CAVI ≥ 9. Random forest analysis revealed that age was the most important factor, followed by lipid metabolism, weight-gain velosity, and glucose metabolism, with sex being the least important. Non-linear regression analysis of the effect of age on CAVI ≥ 9 showed the effect was pronounced after age 60, and the trend was greater in women. Among individuals aged 60 or younger, the aOR of weight-gain velosity for CAVI ≥ 9 was significantly positive (aOR 11.95, 95 %CI 1.13-126.27), while it was not significant for those older than 60. The relationship between weight-gain velosity and CAVI provides a new perspective on CVD risk factors. The effects of age, especially after 60, and weight-gain velosity in early- to middle-adulthood on arterial stiffness are emphasized.

Conclusions

These findings underscore the importance of weight management under age 60, especially in women.

Impact of sleep-disordered breathing on overnight changes in arterial stiffness in patients with acute heart failure

Overnight increases in arterial stiffness associated with sleep-disordered breathing may adversely affect patients with acute heart failure. Thus, we investigated overnight changes in arterial stiffness and their association with sleep-disordered breathing in patients hospitalized for acute heart failure. Consecutive patients with acute heart failure were enrolled. All participants underwent overnight full polysomnography following the initial improvement of acute signs and symptoms of acute heart failure. The arterial stiffness parameter, cardio-ankle vascular index (CAVI), was assessed before and after polysomnography. Overall, 60 patients (86.7% men) were analyzed. CAVI significantly increased overnight (from 8.4 ± 1.6 at night to 9.1 ± 1.7 in the morning, P < 0.001) in addition to systolic and diastolic blood pressure (from 114.1 mmHg to 121.6 mmHg, P < 0.001; and from 70.1 mmHg to 78.2 mmHg, P < 0.001, respectively). Overnight increase in CAVI (ΔCAVI ≥ 0) was observed in 42 patients (70%). The ΔCAVI ≥ 0 group was likely to have moderate-to-severe sleep-disordered breathing (i.e., apnea-hypopnea index ≥15, 55.6% vs 80.9%, P = 0.047) and greater obstructive respiratory events (29.4% vs 58.5%, P = 0.041). In multivariable analysis, moderate-to-severe sleep-disordered breathing and greater obstructive respiratory events were independently correlated with an overnight increase in CAVI (P = 0.033 and P = 0.042, respectively). In patients hospitalized for acute heart failure, arterial stiffness, as assessed by CAVI, significantly increased overnight. Moderate-to-severe sleep-disordered breathing and obstructive respiratory events may play an important role in the overnight increase in cardio-ankle vascular index.

The Prevention of the New Onset of Heart Failure in Hypertensive Patients

In 2014, Japan was estimated to have approximately 27 million patients with hypertension (HT), and the ultimate goal of treatment is to prevent complications of HT, including heart failure (HF). The major structural changes in the heart that cause HF are left ventricular (LV) hypertrophy (LVH) and the resulting LV diastolic dysfunction. However, in patients with HT with well-controlled blood pressure (BP), whether they are in HF stage A (only HT) or B (with organic heart disease) is often unclear. It has been reported that strict BP control suppresses LVH, and the improvement of LVH leads to the suppression of cardiovascular complications. Thus, detecting HF stage B HT and providing appropriate treatment lead to the suppression of HF onset. This review focuses on the detection and treatment of organic heart disease in HT.

Vascular function: a key player in hypertension

The major functions of the arterial system are to "efficiently deliver blood to the peripheral organs and maintain vascular homeostasis". Both the endothelial and medial layer contribute to the three major functions, namely, conversion of pulsatile to steady blood flow, appropriate distribution of blood flow to the target organs, and vascular protection and homeostasis. Vascular dysfunction contributes to the development of cardiovascular diseases through a combination of several mechanisms, including impaired coronary perfusion, cardiac systolic/diastolic dysfunction, microvascular damage, and abnormal hemodynamics in the arterial tree. The representative marker of endothelial function is flow-mediated vasodilatation and that of the medial layer function is pulse wave velocity, and that of the blood supply function of the arterial tree is the ankle-brachial pressure index. In hypertension, vascular dysfunction could also lead to the development of isolated systolic hypertension, isolated diastolic hypertension, and systolic/diastolic hypertension. Vascular dysfunction is involved in a vicious cycle with abnormal blood pressure variability. Furthermore, a vicious cycle may also exist between vascular dysfunction and hypertension. While the significances of vascular function tests to predict future cardiovascular events has been established in cases of hypertension, their usefulness in assessing the effectiveness of management of the vascular functions in hypertension on the cardiovascular outcomes has not yet been fully clarified. Thus, vascular dysfunction plays crucial roles in the pathophysiology of hypertension, and further research is warranted to establish strategies to improve vascular dysfunction in cases of hypertension. Vascular functions in the pathophysiology of hypertension. Vascular dysfunction and elevation of blood pressure are components of a vicious cycle even from their early stages, which including abnormal blood pressure variabilities. This vicious cycle is associated with hypertensive organ damage and also adverse cardiovascular outcomes. Strategies to break this vicious cycle have not yet been fully established.

Serum Malondialdehyde-Oxidized Low-Density Lipoprotein Level Is Associated with Arterial Stiffness by Cardio-Ankle Vascular Index in Coronary Artery Bypass Graft Patients

A high malondialdehyde-oxidized low-density lipoprotein (MDA-oxLDL) level is associated with atherosclerotic cardiovascular diseases and major adverse cardiovascular events. A higher cardio-ankle vascular index (CAVI) is independently associated with an increased risk of cardiovascular events, cardiovascular mortality, myocardial infarction, and stroke in patients with cardiovascular risk. Thus, this study aimed to evaluate the relationship between serum MDA-oxLDL levels and CAVI in patients with triple-vessel coronary artery disease who underwent coronary artery bypass graft (CABG) surgery. Fasting blood samples and baseline characteristics were obtained from 88 patients who had undergone CABG. A commercialized enzyme-linked immunosorbent assay was used to measure MDA-oxLDL levels. An automatic pulse wave analyzer was used to measure CAVI values, and each side of CAVI values of ≥9 was designated as arterial stiffness. In total, 47 participants were assigned to the arterial stiffness group. More patients had diabetes mellitus, were older, and had higher serum MDA-oxLDL levels in the arterial stiffness group than in the control group. A multivariate logistic regression analysis disclosed that MDA-oxLDL and diabetes mellitus were independent predictors of arterial stiffness. Moreover, according to the Spearman's correlation analysis, the serum MDA-oxLDL level was positively associated with both left and right CAVI. Serum MDA-oxLDL levels were positively associated with arterial stiffness in patients who had undergone CABG.

Are Non-Invasive Modalities for the Assessment of Atherosclerosis Useful for Heart Failure Predictions?

Heart failure (HF) is becoming an increasingly common issue worldwide and is associated with significant morbidity and mortality, making its prevention an important clinical goal. The criteria evaluated using non-invasive modalities such as coronary artery calcification, the ankle-brachial index, and carotid intima-media thickness have been proven to be effective in determining the relative risk of atherosclerotic cardiovascular disease. Notably, risk assessments using these modalities have been proven to be superior to the traditional risk predictors of cardiovascular disease. However, the ability to assess HF risk has not yet been well-established. In this review, we describe the clinical significance of such non-invasive modalities of atherosclerosis assessments and examine their ability to assess HF risk. The predictive value could be influenced by the left ventricular ejection fraction. Specifically, when the ejection fraction is reduced, its predictive value increases because this condition is potentially a result of coronary artery disease. In contrast, using these measures to predict HF with a preserved ejection fraction may be difficult because it is a heterogeneous condition. To overcome this issue, further research, especially on HF with a preserved ejection fraction, is required.

The constricting effect of reduced coronary artery compliance on the left ventricle is an important cause of reduced diastolic function in patients with coronary heart disease

Background

Previous studies of left ventricular diastolic function (LVDF) have focused on the decrease in active and passive diastolic function due to ischemic factors but have not investigated if the decrease in compliance of the coronary arteries that bypass the surface of the heart and travel between the myocardium could cause a constricting effect on the ventricular wall like that caused by myocardial fibrosis.

Methods and Results

581 patients diagnosed with coronary heart disease (CHD) were divided into A group (patients are the control group), B group (patients with less than 50% coronary artery stenosis), C group (patients with coronary artery stenosis between 50 and 75%), D group (patients with coronary artery stenosis greater than 75%) according to the degree of coronary stenosis. The diastolic function of the ventricle is reflected by applying the relaxation time constant T value, which refers to the time between peak dp/dt and end-diastolic pressure in the left ventricle. It was concluded that there was a statistical difference in Gensini scores between patients in groups B, C and D (P < 0.001). And multiple linear regression analysis showed that T was correlated with Gensini score and C-dp/dtmax (R = 0.711, P < 0.001). Grouping according to the site of stent implantation and the number of stents implanted, it was found out that the changes in T values before and after left anterior descending artery (LAD) stent implantation were greater than left circumflex artery (LCX) and right coronary artery (RCA) (P < 0.001). And multiple linear regression revealed a correlation between T values and stent length, ventricular stiffness, and C-dp/dtmax (P = 0.001).

Conclusions

The decrease in compliance of the coronary arteries bypassing the surface of the heart and travelling between the myocardium would cause a constricting effect on the ventricular wall like that caused by myocardial fibrosis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-022-02809-0.

Influence of the cardio-ankle vascular index on chronic-phase left ventricular dysfunction after ST-segment elevation myocardial infarction

OBJECTIVE

This study aimed to investigate the possible influence of arterial stiffness assessed by the cardio-ankle vascular index (CAVI) on chronic-phase left ventricular dysfunction in patients with ST-segment elevation myocardial infarction (STEMI).

METHODS

A total of 208 consecutive patients with first STEMI (age, 64 ± 11 years; 86% men) who underwent reperfusion therapy within 12 h of onset were enrolled. We analysed arterial stiffness by measuring CAVI in a stable phase after admission and performed two-dimensional echocardiography at baseline and 7 months' follow-up. Subsequently, we assessed left ventricular global longitudinal strain (LV-GLS) to evaluate left ventricular function. A total of 158 (75.9%) patients underwent baseline cardiac magnetic resonance (CMR). We estimated left ventricular infarct size by measuring peak levels of creatine kinase-myocardial band (CK-MB), and CMR-late gadolinium enhancement (LGE).

RESULTS

On the basis of the median CAVI value, the patients were allocated into high CAVI (CAVI ≥ 8.575) and low CAVI (CAVI < 8.575) groups. The groups showed no statistically significant differences in LV-GLS at baseline (-13.5% ± 3.1 vs. -13.9% ± 2.7%, P  = 0.324). However, LV-GLS was significantly worse in the high CAVI group than in the low-CAVI group at 7 months (-14.0% ± 2.9 vs. -15.6% ± 3.0%, P  < 0.001). Stratified by CAVI and peak CK-MB or LGE, the four groups showed significant differences in LV-GLS at 7 months after STEMI (both P  < 0.001). Multivariate linear regression analysis with the forced inclusion model showed that CAVI was an independent predictor of LV-GLS at 7 months ( P  = 0.015).

CONCLUSION

CAVI early after STEMI onset was significantly associated with chronic-phase LV-GLS. In addition, combining CAVI with CK-MB or LGE improves its predictive ability for evaluation of chronic-phase LV-GLS. Thus, the arterial stiffness assessment by CAVI was an important factor related to chronic-phase left ventricular dysfunction after the first STEMI.

Heart-Ankle Pulse Wave Velocity Is Superior to Brachial-Ankle Pulse Wave Velocity in Detecting Aldosterone-Induced Arterial Stiffness

Primary aldosteronism (PA) is associated with higher arterial stiffness compared to essential hypertension (EH). However, few studies have compared different pulse wave velocity (PWV) parameters to detect aldosterone-induced arterial stiffness. In this study, we aimed to compare the sensitivity in detecting aldosterone-induced arterial stiffness between brachial-ankle PWV (baPWV) and heart-ankle PWV (haPWV). We prospectively enrolled 1006 PA patients and 983 EH patients. Detailed medical history, basic biochemistry data and two PWV measurements (baPWV and haPWV) were collected in both groups. We performed analysis on the original cohort and two propensity score matching (PSM) models (model 1 adjusted for age and sex; model 2 adjusted for age, sex, systolic and diastolic blood pressure). The DeLong test was used to compare areas under receiver operating characteristic curves (AUCs) between baPWV and haPWV to predict PA. In all models, the PA patients had significantly higher baPWV compared to the EH patients. The AUC of haPWV was greater than that of baPWV. In conclusion, haPWV seems to be a better PWV parameter than baPWV in detecting aldosterone-induced arterial stiffness.

Arterial stiffness in health and disease: The role of cardio-ankle vascular index

Arterial stiffness increases with age, as well as in various pathological states, including obesity, diabetes mellitus, smoking, and dyslipidemia, and it has important consequences for cardiovascular health. Arterial stiffness plays a central role in hemodynamic dysfunction characterized by excess pulsatility; specifically, it leads to heart failure, cerebrovascular disease, and renal failure. Among measures of arterial stiffness, carotid-femoral pulse wave velocity is considered as the reference standard; however, it has not been incorporated into routine clinical practice. Cardio-ankle vascular index (CAVI), which is a marker of arterial stiffness measured from the origin of the aorta to the ankle, was developed in 2004. CAVI is based on stiffness parameter β, which is theoretically independent of blood pressure at the time of measurement. CAVI applies stiffness parameter β to arterial segments between the heart and ankle. The measurement of CAVI is simple and well-standardized, and its reproducibility and accuracy are acceptable. Several studies have demonstrated that CAVI is high in patients with various atherosclerotic risk factors, and treatment of cardiovascular risk factors and lifestyle modifications improve CAVI. Several prospective studies have investigated the association between CAVI and future cardiovascular events in the general population and in patients with cardiovascular risk factors. A cut-off value of 9.0 is proposed for predicting patients at a high risk of cardiovascular events. From this review, it is clear that CAVI may be useful in the prevention of cardiovascular disease.

Cardio-ankle vascular index is associated with coronary plaque composition assessed with iMAP-intravascular ultrasound in patients with coronary artery disease

BACKGROUND

The cardio-ankle vascular index (CAVI) is an indicator of arterial stiffness and has been reported to be associated with the severity of coronary artery disease and cardiovascular events. However, whether CAVI can predict the composition of coronary plaques remains unclear.

METHODS

We enrolled 208 patients who underwent percutaneous coronary intervention (PCI) for culprit lesions evaluated with iMAP-intravascular ultrasound (IVUS), a radiofrequency imaging system for characterizing tissues. iMAP-IVUS classified the culprit plaque composition as fibrotic, lipidic, necrotic, or calcified, and the respective absolute volumes [fibrotic volume (FV), lipidic volume (LV), necrotic volume NV, and calcified volume] and their ratios (%) within the total plaque volume were calculated. A plaque with a median %NV of ≥ 33.2% was defined as a larger NV (LNV) plaque. We measured CAVI and divided the patients into two groups according to CAVI ≥8 (high CAVI, n = 164) or <8 (low CAVI, n = 44).

RESULTS

Culprit plaques had significantly greater absolute NV (p = 0.016), %NV (p = 0.01), and smaller %FV (p = 0.02) in patients with high CAVI than in those with low CAVI. Patients with high CAVI had a higher prevalence of LNV plaques in culprit lesions than those with low CAVI (54% vs. 34%, p = 0.026). CAVI correlated significantly and positively with absolute NV, LV, and negatively with %FV. In logistic regression analysis after adjustment for the classic coronary risk factors and possible variables associated with vulnerable plaques, high CAVI had an independent and significant association with the presence of LNV plaques (OR, 3.37; 95% CI, 1.45-7.79; p = 0.0032).

CONCLUSIONS

A high CAVI is associated with the composition of coronary culprit plaques, particularly increased amount of necrotic tissue, in patients with coronary artery disease undergoing PCI .

[Cardio-ankle vascular index (CAVI) in diagnostics, risk and severity evaluation of magistral vessels lesion in patients with cardio-vascular diseases and type 2 diabetes]

Assesment of arterial stiffness the substantional prognostic factor for evaluating complications of cardiovascular diseases (CVD) in patients with atherosclerosis, hypertension and type 2 diabetes, may be performed using different parameters, including cardio-ankle vascular index (CAVI). The main purpose of this review is to analyze data from studies where CAVI is used to test the arterial wall stiffness in magistral vessels. CAVI measurement is non-invasive and performed by portable devices which makes it comfortable for ambulatory use in patients who come for a check-up and also in those who already are hospitalized. It does not require any special knowledge from investigator and the test lasts a couple of minutes long. CAVI does not depend on blood pressure changes and is more specific in structural changes of arterial wall assessment than brachial-ankle pulse wave velocity (baPWV). CAVI shows considerable correlation with markers of CVD like atherosclerotic plaques in vessels, diastolic disfunction of left ventricle and angina pectoris. CAVI may be used for early monitoring and assessing the lesions of target organs in patients with atherosclerosis, chronic hypertension and type 2 diabetes. Establishing CAVI as a standart parameter in assessing patients who are at risk of CVD can help to improve complications prevention, reduce mortality and prolong their lifespan.

Assessment of cardio-ankle vascular index in patients with abdominal aortic aneurysm: An observational study

OBJECTIVES

Arterial stiffness is associated with major adverse cardiovascular events. The aim of this study is to investigate arterial stiffness by cardio-ankle vascular index (CAVI) in patients with abdominal aortic aneurysm (AAA).

METHODS

This observational and cross-sectional study involved 59 subjects with AAA and 32 healthy subjects. All subjects underwent ultrasonography examination. CAVI was measured by VaSera-1000 CAVI instrument.

RESULTS

Mean abdominal aortic diameter of AAA patients and controls were 43.88 ± 9.28 mm and 20.43 ± 3.14 mm, consecutively. Baseline clinical characteristics of the patients and controls were similar for age, presence of hypertension, diabetes, dyslipidemia, coronary artery disease and smoking. Left ventricle ejection fraction and Left ventricle mass index (LVMI) were similar between groups. CAVI was significantly higher in patients with AAA than controls (9.74 ± 1.50 vs. 7.60 ± 1.07, p < 0.001). CAVI was positively correlated with AAA diameter (r = 0.461, p < 0.001) and negatively correlated with left ventricle ejection fraction (r= -0.254, p = 0.015). CAVI >8.3 had a sensitivity 89.8% and a specificity of 78.1% for predicting the presence of AAA in ROC analysis (area under curve = 0.897, 95%CI = 0.816-0.951, p < 0.001).

CONCLUSION

CAVI is increased in patients with AAA. Increased arterial stiffness may be a mechanical link between AAA, coronary artery disease and peripheral artery disease or a common mechanism effects the arterial stiffness, coronary artery disease, peripheral artery disease and AAA. Therefore, CAVI may be used as a valuable marker for risk stratification for the development of AAA in susceptible patients.

Short-term impact of aged garlic extract on endothelial function in diabetes: A randomized, double-blind, placebo-controlled trial

Impaired endothelial function portends an increased risk of cardiovascular disease. Vascular oxidative stress and systemic inflammation play a critical role in the pathogenesis and progression of vascular disease. Aged garlic extract (AGE) may improve impaired vascular endothelial function, while decreasing the progression of atherosclerotic plaque. We hypothesized that AGE may improve endothelial function, and in this study, we examined this hypothesis to determine whether this can be achieved over a period of 3 months, measured by the cardio-ankle vascular index (CAVI), by reducing intracellular oxidant stress and stimulating nitric oxide generation in endothelial cells. We conducted a double-blinded placebo controlled, randomized clinical trial to investigate the effects of AGE on CAVI in subjects with type 2 diabetes mellitus. A total of 65 individuals (38 men and 27 women) with a mean age of 58.8±11.1 years were enrolled and randomized to the AGE or placebo group in a double-blind placebo controlled trial. An ANOVA model with treatment as the main effect was used to compare changes in CAVI from baseline to follow-up between groups. The primary objective of this study was reduction in CAVI over a 3-month period. In the AGE group, CAVI was reduced on average by 0.71±1.27 vs. a mean reduction of 0.13±0.94 in the placebo group (P=0.04). On the whole, this study demonstrates that AGE has a positive impact on endothelial function in patients with T2DM and may play a role in the primary prevention of cardiovascular disease.

Disease activity is associated with LV dysfunction in rheumatoid arthritis patients without clinical cardiovascular disease

OBJECTIVES

The cross-sectional study aimed to assess left ventricular systolic function using global longitudinal strain (GLS) by speckle-tracking echocardiography (STE) and arterial stiffness using cardio-ankle vascular index (CAVI) in Thai adults with rheumatoid arthritis (RA) and no clinical evidence of cardiovascular disease (CVD).

METHODS

Confirmed RA patients were selected from a list of outpatient attendees if they were 18 years (y) without clinical, ECG and echocardiographic evidence of CVD, diabetes mellitus, chronic kidney disease, and excess alcoholic intake. Controls were matched with age and sex to a list of healthy individuals with normal echocardiograms. All underwent STE and CAVI.

RESULTS

60 RA patients (females = 55) were analysed. Mean standard deviation of patient and control ages were 50 ± 10.2 and 51 ± 9.9 y, respectively, and mean duration of RA was 9.0 ± 6.8 y. Mean DAS28-CRP and DAS28-ESR were 2.9 ± 0.9 and 3.4 ± 0.9, respectively. There was no between-group differences in left ventricular ejection fraction (LVEF), LV sizes, LVMI, LV diastolic function and CAVI were within normal limits but all GLSs values was significantly lower in patients vs. controls: 17.6 ± 3.4 vs 20.4 ± 2.2 (p = 0.03). Multivariate regression analysis demonstrated significant correlations between GLSs and RA duration (p = 0.02), and GLSs and DAS28-CRP (p = 0.041).

CONCLUSIONS

Patients with RA and no clinical CV disease have reduced LV systolic function as shown by lower GLSs. It is common and associated with disease activity and RA disease duration. 2D speckle-tracking GLSs is robust in detecting this subclinical LV systolic dysfunction.

Marker Of Sepsis Severity Is Associated With The Variation In Cardio-Ankle Vascular Index (CAVI) During Sepsis Treatment

Introduction

The main pathophysiology of sepsis is considered to be circulation crisis with an imbalance of vasodilation and vasoconstriction mechanisms, which contributes to multiple organ failure. However, sepsis-induced hemodynamic changes have not been fully validated by novel arterial stiffness parameter. The aim of this study was to clarify the acute vascular alteration and hemodynamic change in sepsis using cardio-ankle-vascular index (CAVI).

Methods

Twenty-one Japanese patients (14 males and 7 females, age 62.8 ± 19.0 years) with sepsis were recruited. CAVI was measured before and 1-week after sepsis treatment.

Results

The leading underlying cause of sepsis was pyelonephritis, followed by pneumonia, lung abscess, hepatic abscess and cholecystitis. All subjects recovered from sepsis. Analysis of all subjects showed a significant increase in CAVI after 1-week treatment (7.9 ± 2.4 to 9.6 ± 1.8, P < 0.001), but no significant change in blood pressure (BP) was observed. Significant correlations were observed for all combinations among the change in CAVI, systolic BP and ln[procalcitonin (PCT)], respectively. Additionally, in subjects with PCT at presentation ≥2.0 ng/mL, the increase in CAVI after treatment was significantly greater compared to those with PCT < 2.0 ng/mL (2.4 ± 1.6 vs 1.1 ± 0.9, P = 0.037).

Discussion

CAVI may reflect sepsis-induced vascular alteration which is not indicated by BP change, and is associated with sepsis severity. These findings suggest the usefulness of CAVI in the management of circulatory failure in sepsis patients.

Arterial Stiffness Assessed by Cardio-Ankle Vascular Index

Arterial stiffness is an age-related disorder. In the medial layer of arteries, mechanical fracture due to fatigue failure for the pulsatile wall strain causes medial degeneration vascular remodeling. The alteration of extracellular matrix composition and arterial geometry result in structural arterial stiffness. Calcium deposition and other factors such as advanced glycation end product-mediated collagen cross-linking aggravate the structural arterial stiffness. On the other hand, endothelial dysfunction is a cause of arterial stiffness. The biological molecular mechanisms relating to aging are known to involve the progression of arterial stiffness. Arterial stiffness further applies stress on large arteries and also microcirculation. Therefore, it is closely related to adverse outcomes in cardiovascular and cerebrovascular system. Cardio-ankle vascular index (CAVI) is a promising diagnostic tool for evaluating arterial stiffness. The principle is based on stiffness parameter β, which is an index intended to assess the distensibility of carotid artery. Stiffness parameter β is a two-dimensional technique obtained from changes of arterial diameter by pulse in one section. CAVI applied the stiffness parameter β to all of the arterial segments between heart and ankle using pulse wave velocity. CAVI has been commercially available for a decade and the clinical data of its effectiveness has accumulated. The characteristics of CAVI differ from other physiological tests of arterial stiffness due to the independency from blood pressure at the time of examination. This review describes the pathophysiology of arterial stiffness and CAVI. Molecular mechanisms will also be covered.

Lipid Parameters are Independently Associated with Cardio-Ankle Vascular Index (CAVI) in Healthy Japanese Subjects

AIM

To investigate the associations of conventional lipid parameters with arterial stiffness assessed by cardio-ankle vascular index (CAVI).

METHODS

A retrospective cross-sectional study was conducted in 23,257 healthy Japanese subjects (12,729 men and 10,528 women, aged 47.1±12.5 years, body mass index (BMI) 22.9±3.4 kg/m2) who underwent health screening between 2004 and 2006 in Japan.

RESULTS

Male subjects had significantly higher BMI, CAVI and triglycerides (TG), and lower high-density lipoprotein cholesterol (HDL-C) compared to female subjects. After adjusting for confounders, including gender, age, systolic blood pressure and BMI identified by multiple regression analysis, adjusted CAVI was lower in normolipidemic than in dyslipidemic subjects. Among dyslipidemic subjects, those with hypertriglyceridemia had higher adjusted CAVI. A trend test detected linear relations between adjusted CAVI and all the conventional lipid parameters throughout the entire range of serum levels. After adjusting for confounders, logistic regression models showed that all lipid parameters contributed independently to high CAVI (≥90th percentile). Receiver-operating-characteristic analysis determined reliable cut-off values of 93 mg/dl for TG (area under the curve, AUC= 0.735), 114 mg/dl for low-density lipoprotein cholesterol (AUC=0.614) and 63 mg/dl for HDL-C (AUC=0.728) in predicting high CAVI. These cut-off values were confirmed to independently predict high CAVI in a bivariate logistic regression model.

CONCLUSION

The present study demonstrated independent contribution of conventional lipid parameters to CAVI, indicating a possible association of lipid parameters with early vascular damage.

Sex differences in associations of cardio-ankle vascular index with left ventricular function and geometry

The cardio-ankle vascular index (CAVI) is a measure of global arterial stiffness. We hypothesized that CAVI is associated with left ventricular (LV) function and geometry in individuals without structural heart disease. We measured CAVI in 600 participants (mean age 60.3±14.6 years, 54% men) without history of atherosclerotic cardiovascular disease who were referred for transthoracic echocardiography. Linear regression analysis was used to assess the association of CAVI with LV function (peak mitral annular systolic s' and early diastolic velocity e') and structure (LV mass index (LVMI) and relative wall thickness (RWT)). Older age, male sex, lower body mass index, history of hypertension, diabetes and chronic kidney disease were each associated with a higher CAVI (adjusted R² = 0.56, all p < 0.01). A higher CAVI was associated with lower s' and e', and greater RWT, independent of age, sex, systolic BP and other conventional cardiovascular risk factors (all p < 0.05); a borderline association of higher CAVI with greater LVMI ( p = 0.05) was present. Associations with e', s' and RWT were similar in women and men but the association with LVMI was stronger in women than in men ( p for interaction = 0.02, multivariable-adjusted β = 6.92, p < 0.001 in women; p > 0.1 in men). In conclusion, a higher CAVI, a measure of global arterial stiffness, is associated with worse LV systolic function, worse diastolic relaxation, and greater LV RWT in both men and women, and with LVMI in women.

Protocol for Evaluating the Cardio-Ankle Vascular Index to Predict Cardiovascular Events in Japan: A Prospective Multicenter Cohort Study

INTRODUCTION

The cardio-ankle vascular index (CAVI) was developed in Japan and is a blood pressure-independent index of arterial stiffness from the origin of the aorta to the ankle. In recent years, it has been studied by many researchers worldwide, and it is strongly anticipated that it will play a role as a predictive factor for arteriosclerotic diseases. The objective of this study was to examine the benefits of using CAVI as a predictor of cardiovascular events in high-risk patients.

METHODS AND DESIGN

This prospective multicenter study to evaluate the usefulness of the CAVI to predict cardiovascular events in Japan (CAVI-J) is a cohort study with central registration. Participants (n = 3,000) will be scheduled to enroll and data will be collected for up to 5 years from entry of participants into the study. To be eligible to participate in the CAVI-J study, individuals have to be aged between 40 and 74 years and have at least one of the following risk factors for arteriosclerosis: (1) type 2 diabetes mellitus; (2) high-risk hypertension; (3) metabolic syndrome; (4) chronic kidney disease (stage 3), or (5) history of coronary artery disease or noncardiogenic cerebral infarction. The primary endpoints of this study are cardiovascular death, nonfatal myocardial infarction, and stroke. The secondary endpoints are composite cardiovascular events including all cause death, angina pectoris with revascularization, new incidence of peripheral artery disease, abdominal aortic aneurysm, aortic dissection, heart failure requiring hospitalization, and deterioration in renal function. The cutoff for CAVI against the incidence of cardiovascular events will be determined.

Inverse relationship of cardioankle vascular index with BMI in healthy Japanese subjects: a cross-sectional study

Objective

The objective of this study is to investigate the association of body mass index (BMI) with arterial stiffness assessed by cardioankle vascular index (CAVI).

Subjects and methods

A retrospective cross-sectional study was conducted in 23,257 healthy Japanese subjects (12,729 men and 10,528 women, aged 47.1 ± 12.5 years, BMI 22.9 ± 3.4 kg/m²) who underwent health screening between 2004 and 2006 in Japan. Exclusion criteria were current medication use and a past history of cardiovascular disease, hypertension, stroke, diabetes, and nephritis.

Results

Male subjects showed significantly higher BMI, CAVI, and triglycerides and lower high-density lipoprotein (HDL)-cholesterol compared with female subjects. Next, the subjects were divided into tertiles of BMI: lower, middle, and upper, in a gender-specific manner. After adjusting for confounders including age, systolic blood pressure, and HDL-cholesterol identified by multiple regression analysis, the mean CAVI decreased progressively as BMI tertile increased in both genders. Furthermore, a negative inverse relationship between BMI and adjusted CAVI was observed throughout the BMI distribution. Multivariate logistic regression model for contributors of high CAVI (≥90th percentile) identified obesity (odds ratios (95% confidence interval): 0.804 (0.720–0.899)], older age [15.6 (14.0–17.4)], male gender [2.26 (2.03–2.51)], hypertension [2.28 (2.06–2.54)], impaired fasting glucose [1.17 (1.01–1.37)], and low HDL-cholesterol [0.843 (0.669–1.06)] as independent factors.

Conclusion

We demonstrated an inverse relationship between CAVI and BMI in healthy Japanese subjects, suggesting that systemic accumulation of adipose tissue per se may lead to a linear decrease of arterial stiffness in nonobese and obese subjects without metabolic disorders.

Impact of a Proprietary Standardized Olive Fruit Extract (SOFE) on Cardio-Ankle Vascular Index, Visual Analog Scale and C-Reactive Protein Assessments in Subjects with Arterial Stiffness Risk

INTRODUCTION

The chemical components of olive fruit provide a wide range of cardiovascular benefits. Arterial stiffness is an important cardiovascular risk factor and can be assessed using the Cardio-Ankle Vascular Index (CAVI).

OBJECTIVE

The objective of this study was to assess the impact of a proprietary standardized olive fruit extract (SOFE) in subjects at risk for arterial stiffness.

METHODS

Twelve of 36 subjects were assigned to each of the following groups for this 11-day, double-blind, placebo-controlled study: Group 1: 250 mg SOFE-50 mg active ingredient, hydroxytyrosol (dosage achieved with two capsules per day); Group 2: 500 mg SOFE-100 mg active ingredient, hydroxytyrosol (dosage achieved with two capsules per day); and Group 3: placebo.

RESULTS

All three groups showed a decrease in CAVI scores, although no significant between-group differences were observed. Group 2 had the largest reduction, with mean CAVI scores decreasing from 11.02 to 8.91. Group 2 showed the strongest response in visual analog scale (VAS) energy intensity (11.71% increase). Results for C-reactive protein (CRP) blood levels showed no changes of statistical significance between groups. Mean triglyceride levels from Group 2 decreased by 21.64%, the most significant change among all three groups.

CONCLUSIONS

SOFE, an olive fruit extract containing many of the phytochemicals shown to provide cardiovascular benefits, was safe and well-tolerated. SOFE 500 mg had a greater effect on CAVI scores, suggesting improved arterial elasticity, and a clear reduction in triglycerides compared with placebo and SOFE 250 mg. The decreased CAVI scores suggest that increasing high-density lipoprotein cholesterol and lowering triglycerides with SOFE could potentially reduce patients' risk of developing atherosclerosis. Although more studies are needed, positive cardiovascular health trends, including improved vessel elasticity and positive triglyceride effects, were evident with SOFE.

Assessment of arterial stiffness in patients with venous thromboembolism: Separate or continuous circuits?

Objectives The aim of this study is to evaluate the association of venous thromboembolism with arterial stiffness by cardio-ankle vascular index method. Method We included 52 patients with a documented lower extremity venous thromboembolism within the last six months and 52 healthy subjects to this cross sectional observational study. Results Cardio-ankle vascular index (8.58 ± 1.60 versus 7.05 ± 1.44, p < 0.001, respectively) and systolic blood pressure (128.02 ± 7.13 mmHg versus 123.94 ± 8.12 mmHg, p = 0.008, respectively) were significantly higher among patients with venous thromboembolism than controls. Cardio-ankle vascular index was an independent predictor of venous thromboembolism in multivariate logistic regression analysis (p < 0.001, odds ratio = 1.864, 95% confidence interval = 1.370-2.536). Cardio-ankle vascular index value > 7.8 had a sensitivity of 82.7% and a specificity of 80.8% for predicting venous thromboembolism (area under curve = 0.789, 95% confidence interval = 0.698-0.863, p < 0.001) in receiver operating characteristic curve analysis. Conclusion We found that arterial stiffness was increased in patients with venous thromboembolism which highlights the fact that arterial and venous circulation is in continuum and an insult may affect both of these circuits.

Clinical assessment of arterial stiffness with cardio-ankle vascular index: theory and applications

Arterial stiffness is often assessed in clinical medicine, because it is not only an important factor in the pathophysiology of blood circulation but also a marker for the diagnosis and the prognosis of cardiovascular diseases. Many parameters have so far been proposed to quantitatively represent arterial stiffness and distensibility, such as pressure-strain elastic modulus (Ep), stiffness parameter (β), pulse wave velocity (PWV), and vascular compliance (Cv). Among these, PWV has been most frequently applied to clinical medicine. However, this is dependent on blood pressure at the time of measurement, and therefore it is not appropriate as a parameter for the clinical evaluation of arterial stiffness, especially for the studies on hypertension. On the contrary, stiffness parameter β is an index reflecting arterial stiffness without the influence of blood pressure. Recently, this parameter has been applied to develop a new arterial stiffness index called cardio-ankle vascular index (CAVI). Although this index is obtained from the PWV between the heart and the ankle, it is essentially similar to the stiffness parameter β, and therefore it does not depend on blood pressure changes during the measurements. CAVI is being extensively used in clinical medicine as a measure for the evaluation of cardiovascular diseases and risk factors related to arteriosclerosis. In the present article, we will explain the theoretical background of stiffness parameter β and the process to obtain CAVI. And then, the clinical utility of CAVI will be overviewed by reference to recent studies.

Assessment of Arterial Stiffness Using the Cardio-Ankle Vascular Index

BACKGROUND

Arterial stiffness is an independent predictor of outcomes for patients with cardiovascular disease. Although measurement of pulse wave velocity is a widely accepted, noninvasive approach for the assessment of arterial stiffness, its accuracy is affected by changes in blood pressure.

SUMMARY

The cardio-ankle vascular index (CAVI) is an index of the overall stiffness of the artery from the origin of the aorta to the ankle and is theoretically independent of blood pressure at the time of measurement. CAVI increases linearly with age and is elevated even in mild arteriosclerotic disease. It can identify differences in the degree of arteriosclerosis among patients with severe arteriosclerotic disease and better reflects the severity of disease of the coronary artery than does brachial-ankle pulse wave velocity. Patients with higher CAVI values show a poor prognosis compared with those with lower CAVI values. Furthermore, CAVI can be lowered by controlling diabetes mellitus and hypertension.

KEY MESSAGES

The primary aims of assessing arterial stiffness using CAVI are to assist in the early detection of arteriosclerosis, allowing timely treatment and lifestyle modification, and to quantitatively evaluate the progression of disease and the effectiveness of treatment. Whether CAVI-guided therapy can improve prognosis in high-risk patients needs to be further examined to confirm the clinical usefulness of this measure.

Cardio-ankle vascular index predicts for the incidence of cardiovascular events in obese patients: a multicenter prospective cohort study (Japan Obesity and Metabolic Syndrome Study: JOMS)

OBJECTIVE

The cardio-ankle vascular index (CAVI) is an index of arterial stiffness less dependent on blood pressure and an indicator suitable for assessing the arterial dysfunction. However, it remains unclear whether CAVI can predict the outcome of cardiovascular diseases (CVD) in obese patients.

METHODS

A total of 425 obese Japanese outpatients (189 men and 236 women, mean age: 51.5 years) were enrolled in a multicenter prospective cohort Japan, the Japan Obesity and Metabolic Syndrome Study (JOMS). Primary analysis regarding measurements of cardiovascular risk factors including CAVI and the occurrence of macrovascular complications was based on following the participants over a 5-year period.

RESULTS

Of the eligible patients, 300 (78%) were followed into the fifth year. During the study period, 15 coronary heart disease, 7 stroke, and 6 arteriosclerosis obliterans events occurred. All events occurred in 28 patients, and CVD incidence rate was 15.8 per 1000 person-years. In the analysis of adjusted models for traditional risk factors, CAVI was a significant factor for the incidence of events. In addition, high CAVI and low HDL-cholesterol were significant factors for the incidence of events in Cox stepwise multivariate analysis when age- and sex-adjusted (CAVI [per 1]: HR = 1.44 [1.02-2.02], p = 0.037; HDL-cholesterol [per 1 mmol/L]: HR = 0.20 [0.06-0.69], p = 0.011). In addition, CAVI added value to atherosclerotic cardiovascular disease risk score in predicting the development of CVD.

CONCLUSION

This study demonstrates for the first time that CAVI is an effective predictor of CVD events in obese patients.

Cardio-ankle vascular index (CAVI) differentiates pharmacological properties of vasodilators nicardipine and nitroglycerin in anesthetized rabbits

Cardio-ankle vascular index (CAVI) has been developed for measurement of vascular stiffness from the aorta to tibial artery, which is clinically utilized for assessing the progress of arteriosclerosis. In this study, we established measuring system of the CAVI in rabbits, and assessed whether the index could reflect different pharmacological actions of nitroglycerin and nicardipine on the systemic vasculature. Rabbits were anesthetized with halothane, and the CAVI was calculated from the well-established basic equations with variables obtained from brachial and tibial blood pressure and phonocardiogram. Nicardipine (1, 3 and 10 μg/kg, i.v.) decreased the blood pressure, femoral vascular resistance, and heart-ankle pulse wave velocity (haPWV). Meanwhile, no significant change was detected in the CAVI at the low or middle dose, which reflects the defining feature of the CAVI that is independent of blood pressure. The index increased at the high dose. Nitroglycerin (2, 4 and 8 μg/kg, i.v.) decreased the blood pressure, femoral vascular resistance, and haPWV. Meanwhile, the CAVI was decreased during the nitroglycerin infusion, which may reflect its well-known pharmacological action dilating conduit arteries. These results suggest that the CAVI differentiates the properties of these vasodilators in vivo.

The Role of Monitoring Arterial Stiffness with Cardio-Ankle Vascular Index in the Control of Lifestyle-Related Diseases

Arteriosclerosis is a major contributor to cardiovascular diseases. One of the difficulties in controlling those diseases is the lack of a suitable indicator of arteriosclerosis or arterial injury in routine clinical practice. Arterial stiffness was supposed to be one of the monitoring indexes of arteriosclerosis. Cardio-ankle vascular index (CAVI) is reflecting the stiffness of the arterial tree from the origin of the aorta to the ankle, and one of the features of CAVI is independency from blood pressure at a measuring time. When doxazosin, an α1-adrenergic blocker, was administered, CAVI decreased, indicating that arterial stiffness is composed of both organic stiffness and functional stiffness, which reflects the contraction of arterial smooth muscle. CAVI shows a high value with aging and in many arteriosclerotic diseases, and is also high in persons possessing main coronary risk factors such as diabetes mellitus, metabolic syndrome, hypertension and smoking. Furthermore, when the most of those risk factors were controlled by proper methods, CAVI improved. Furthermore, the co-relationship between CAVI and heart function was demonstrated during treatment of heart failure. This paper reviews the principle and rationale of CAVI, and discusses the meaning of monitoring CAVI in following up so-called lifestyle-related diseases and cardiac dysfunction in routine clinical practice.

Assessment of arterial stiffness in patients with chronic lower extremity venous disease: An observational study

OBJECTIVES

Arterial stiffness is associated with major adverse cardiovascular events. Chronic venous insufficiency (CVI) is severe form of chronic venous disease (CVD). The aim of this study is to investigate arterial stiffness by cardio-ankle vascular index (CAVI) in patients with CVI.

METHODS

This observational and cross-sectional study involved 87 subjects with CVI and 86 healthy subjects. All subjects underwent ultrasonography examination. CAVI was measured by VaSera-1000 CAVI instrument.

RESULTS

High density lipoprotein cholesterol (HDL) was significantly lower in patients with CVI than controls (46.83 ± 9.25 mg/dl vs 51.33 ± 11.13 mg/dl, p = 0.004). Body mass index (BMI) was significantly higher in CVI patients than controls (28.53 ± 4.10 kg/m(2) vs 26.37 ± 5.16 kg/m(2), p = 0.003). Ankle brachial index (ABI) was significantly lower in patients with CVI compared to controls (1.08 ± 0.08 vs 1.14 ± 0.11, p < 0.001). CAVI was significantly higher in patients with CVI than controls (7.94 ± 1.37 vs 6.73 ± 1.16, p < 0.001). Mean arterial pressure (MAP) was significantly higher in patients with CVI than control group (105.41 ± 10.77 mmHg vs 99.70 ± 11.17 mmHg, p = 0.001). CAVI (p < 0.001, Odds ratio (OR) = 2.033, 95% Confidence interval (CI) = 1.493-2.768), ABI (p = 0.003, OR = 0.003, 95% CI = 0.001-0.137), female sex (p < 0.001, OR = 3.949, 95% CI = 1.613-9.663), and HDL (p < 0.001, OR = 0.923, 95% CI = 0.883-0.964) were the independent predictors of CVI. A CAVI value > 7.9 had a sensitivity 64.4% and a specificity of 94.7% for predicting the presence of CVI in ROC analysis (area under curve = 0.791, 95% CI = 0.723-0.849, p < 0.001).

CONCLUSION

CAVI is independently increased in CVI patients. Therefore CVI may be accepted a form of vascular sclerosis and vascular system should be evaluated in continuum not isolated.

Serum neutrophil gelatinase-associated lipocalin levels and aortic stiffness in noncritical coronary artery disease

AIM

The aim of this study was to establish the degree of aortic stiffness and levels of neutrophil gelatinase-associated lipocalin (NGAL) in patients with stable ischemic heart disease.

MATERIALS AND METHODS

Patients who were found to have stable, noncritical lesions on coronary angiography were included in the study [noncritical coronary artery disease (CAD)]. The control group consisted of those patients who had similar risk profiles and metabolic parameters without atherosclerosis on angiography.

RESULTS

A total of 101 patients were included in the study of which 56 had noncritical CAD. Whereas the aortic strain (9.11 ± 3.4 vs. 14.01 ± 4.1%, p < 0.001) and aortic distensibility (3.98 ± 1.9 10(-6) cm(2)/dyn vs. 6.33 ± 2.3 10(-6) cm(2)/dyn, p < 0.001) were lower in the noncritical CAD group, the aortic stiffness index was higher (6.34 ± 3.9 vs. 3.37 ± 2.4, p < 0.001) as compared to controls. Serum NGAL levels were higher in the noncritical CAD group (79.29 ± 38.8 vs. 48.05 ± 21.4 ng/ml, p < 0.001). NGAL levels were negatively correlated with aortic strain (p < 0.01, r = 0.57) and distensibility (p < 0.001, r = 0.62), but positively correlated with the aortic stiffness index (p < 0.001, r = 0.72).

CONCLUSION

We show that in patients with noncritical CAD, the degree of aortic stiffness and NGAL levels are higher. These markers can be used as tools for further risk stratification of patients with noncritical CAD.

Association between invasively measured central aortic pressure and left ventricular diastolic function in patients undergoing coronary angiography

BACKGROUND

Because of the invasive nature of catheterization, limited information is available on hemodynamic interaction between the left ventricle and aorta using invasive aortic pressure monitoring. Our aim was to investigate whether parameters of invasively measured central aortic pressure waveform were related with those of left ventricular (LV) diastolic function.

METHODS

A total of 153 consecutive stable patients (mean age = 64±11 years; 62% men) undergoing invasive coronary angiography (ICA) and transthoracic echocardiography (TTE) were prospectively evaluated. Central aortic pressure waveform was obtained at the ascending aorta using a pigtail catheter before ICA. We calculated pulse pressure (PP), fractional PP (FPP; the ratio of PP to mean pressure), pulsatility index (PI; the ratio of PP to diastolic pressure), augmentation index, wave reflection time, and ejection duration and analyzed their associations with parameters of LV diastolic function in TTE.

RESULTS

Most patients (n = 135/153; 88.2%) had significant stenosis (≥50%) of ≥1 epicardial coronary arteries. In multiple linear regression analyses, e' and E/e' were significantly correlated with PP, FPP, and PI even after adjustment for potential confounders. There were no significant correlations between other parameters of LV diastolic function, including E/A, deceleration time, and left atrial volume index and parameters of central aortic pressure wave.

CONCLUSIONS

Invasively measured central aortic PP, FPP, and PI were independently associated with e' and E/e' in patients undergoing ICA. This result adds to the evidence of a close interaction between LV diastolic function and aortic stiffness in this population.

Nonalcoholic fatty liver disease as a risk factor of arterial stiffness measured by the cardioankle vascular index

Nonalcoholic fatty liver disease (NAFLD) is associated with risk factors for cardiovascular disease. The cardioankle vascular index (CAVI), a new measure of arterial stiffness, was recently developed and is independent of blood pressure. We investigated whether NAFLD is associated with arterial stiffness as measured using the CAVI in an apparently healthy population.A total of 2954 subjects without any known liver diseases were enrolled. NAFLD was diagnosed via typical ultrasonography. The clinical characteristics examined included age, sex, body mass index (BMI), waist circumference (WC), and the levels of aspartate aminotransferase, alanine aminotransferase, total cholesterol, high-density lipoprotein-cholesterol, low-density lipoprotein-cholesterol triglycerides, and glucose. Arterial stiffness was defined using an age- and sex-specific threshold of the upper quartile of the CAVI.NAFLD was found in 1249 (42.3%) of the analyzed subjects. Using an age-, sex-, and BMI-adjusted model, NAFLD was associated with a 42% increase in the risk for arterial stiffness (highest quartile of the CAVI). The risk for arterial stiffness increased according to the severity of NAFLD (adjusted odds ratio [95% confidence interval], 1.27 [1.02 - 1.57] vs 1.78 [1.37 - 2.31], mild vs moderate-to-severe, respectively). When adjusted for other risk factors, including BMI, WC, smoking status, diabetes, and hypertension, these relationships remained statistically significant.Patients with NAFLD are at a high risk for arterial stiffness regardless of classical risk factors. The presence of cardiometabolic risk factors may attenuate the prediction of arterial stiffness by means of NAFLD presence. Thus, physicians should carefully assess subjects with NAFLD for atherosclerosis and associated comorbidities.

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.

Evaluation of blood pressure control using a new arterial stiffness parameter, cardio-ankle vascular index (CAVI)

Arterial stiffness has been known to be a surrogate marker of arteriosclerosis, and also of vascular function. Pulse wave velocity (PWV) had been the most popular index and was known to be a predictor of cardiovascular events. But, it depends on blood pressure at measuring time. To overcome this problem, cardio-ankle vascular index (CAVI) is developed. CAVI is derived from stiffness parameter β by Hayashi, and the equation of Bramwell-Hill, and is independent from blood pressure at a measuring time. Then, CAVI might reflect the proper change of arterial wall by antihypertensive agents.

CAVI shows high value with aging and in many arteriosclerotic diseases and is also high in persons with main coronary risk factors. Furthermore, CAVI is decreased by an administration of α₁ blocker, doxazosin for 2-4 hours, Those results suggested that CAVI reflected the arterial stiffness composed of organic components and of smooth muscle cell contracture. Angiotensin II receptor blocker, olmesartan decreased CAVI much more than that of calcium channel antagonist, amlodipine, even though the rates of decreased blood pressure were almost same. CAVI might differentiate the blood pressure-lowering agents from the point of the effects on proper arterial stiffness.

This paper reviewed the principle and rationale of CAVI, and the possibilities of clinical applications, especially in the studies of hypertension.

Arterial stiffness determined according to the cardio-ankle vascular index is associated with paroxysmal atrial fibrillation: a cross-sectional study

BACKGROUND

Several lines of evidence suggest that atrial fibrillation (AF) may be a consequence of vascular disease. We investigated the relationship between cardio-ankle vascular index (CAVI), a new index of arterial stiffness, and the presence of paroxysmal AF (PAF).

METHODS AND RESULTS

181 outpatients (91 patients with PAF and 90 age- and gender-matched subjects without PAF) were analysed for their sinus rhythm. The CAVI was significantly higher in patients with PAF than in subjects without PAF (9.0±1.0 vs 8.7±0.8, p<0.01). In all subjects, the CAVI was significantly correlated with the left ventricular mass index (r=0.30, p<0.01), left atrial diameter (r=0.22, p<0.01), and augmentation index, a parameter of wave reflection (r=0.32, p<0.01), in addition to age, systolic blood pressure and pulse pressure. Logistic analysis demonstrated that the CAVI was independently associated with PAF even after adjustment for confounding factors. The adjusted OR of PAF was 1.8 for each unit increase in the CAVI (p=0.01).

CONCLUSIONS

Our finding suggests that increased arterial stiffness may be involved in the maintenance of AF.

Low serum level of secreted frizzled-related protein 5, an anti-inflammatory adipokine, is associated with coronary artery disease

OBJECTIVE

Secreted frizzled-related protein 5 (SFRP5) is an anti-inflammatory adipokine that is associated with insulin resistance in animals. To extend these observations to humans, we investigated the association of serum SFRP5 levels in subjects with and without coronary artery disease (CAD).

METHODS

Subjects (n=185, 68±11 years, 79% male) suspected of having CAD were enrolled in the study and were divided into two groups, CAD and non-CAD subjects, according to the results of their coronary angiographies. Serum SFRP5 levels of the subjects were measured by an enzyme-linked immunosorbent assay.

RESULTS

The serum SFRP5 levels in the subjects with CAD were significantly lower than those in the non-CAD subjects (median [interquartile range]: 47.7 [26.6] vs. 52.4 [29.6] ng/mL, respectively; p=0.02). The serum SFRP5 levels significantly correlated with body mass index, the homeostasis model of assessment of insulin resistance, adiponectin levels, and CAD severity. Multivariate logistic regression analysis revealed that a decreased serum SFRP5 level (log transformed) was independently associated with CAD for all subjects (adjusted odds ratio, 0.36; 95% confidence interval, 0.14-0.94; p=0.03).

CONCLUSION

Serum SFRP5 levels are significantly associated with CAD in humans, suggesting that low SFRP5 levels may contribute to CAD.

Negative associations between arterial stiffness parameter evaluated by cardio-ankle vascular index and serum low-density lipoprotein cholesterol concentration in early-stage atherosclerosis

The cardio-ankle vascular index (CAVI), calculated values from cardio-ankle pulse wave velocity and blood pressure, corresponds predominantly to the stiffness of the aorta and peripheral arteries of the lower limbs. However, the reported associations between CAVI and serum low-density lipoprotein cholesterol (LDL-C) levels remain inconsistent. A cross-sectional study of 1878 consecutive patients (mean age: 59.2 years) who underwent general health checkup showed a negative association between CAVI and serum LDL-C or non-high-density lipoprotein cholesterol (non-HDL-C) concentrations with age-adjusted correlation and multiple regression analysis. Using the similar analyses divided by the status of risk factors and degree of maximum carotid intima-media thickness (maxIMT), negative correlations between CAVI and LDL-C or non-HDL-C levels were observed only in nonrisk groups including nondiabetics patients or patients with maxIMT <1.0 mm, in those with expected low extent of advanced atherosclerotic lesions. In contrast, such a correlation was not found in each comparable risk-loaded group.