Augmentation Index In Patients Research Articles

Study Protocol of a Prospective, Monocentric, Single-Arm Study Investigating the Correlation of Endograft Properties with Aortic Stiffness in Abdominal Aortic Aneurysm Patients Subjected to Endovascular Aortic Repair.

The number of endovascular aortic repairs (EVARs) has surpassed the number of open surgical repairs of abdominal aortic aneurysms (AAAs) worldwide. The available commercial endoprostheses are composed of materials that are stiffer than the native aortic wall. As a consequence, the implantation of stent-graft endoprostheses during EVAR increases aortic rigidity and thus aortic stiffness, resulting in a decrease in abdominal aorta compliance. EVAR has been found to have a possibly harmful effect not only on heart functions but also on other vascular beds, including kidney function, due to the decrease in aortic compliance that it causes. Aortic stiffness is measured by various hemodynamic indices like the pulse wave velocity (PWV), the central aortic pressure (CAP), and the augmentation index (AIx). In the literature, there are increasing numbers of studies investigating the properties of endografts, which are strongly related to increases in aortic stiffness. However, there is a lack of data on whether there is a correlation between the length of various endografts implanted during EVAR and the increase in the PWV, CAP, and AIx postoperatively compared to the preoperative values. The aim of this prospective, observational, monocentric, single-arm study is to investigate the correlation between endograft length and the postoperative increase in the PWV, CAP, and AIx in patients subjected to EVAR. Additionally, this study intends to identify other endograft properties related to increases in the PWV, CAP, and AIx. Other endpoints to be studied are the existence of immediate postoperative myocardial and kidney injury after EVAR. The prediction of cardiovascular events caused by endograft-related increased aortic stiffness could contribute to the improvement of various endograft properties so that the impact of endografts on the native aortic wall can be minimized.

Exploring the role of adult attachment, major depression and childhood trauma in arterial stiffness: A preliminary study

ObjectivePrior research indicates a noteworthy and intricate connection between depression and subclinical atherosclerosis. Nevertheless, the biological and psychological mechanisms that underlie this association are not yet fully understood. To address this gap, this exploratory study aimed to examine the relationship between active clinical depression and arterial stiffness (AS), with a particular focus on the potential mediating roles of attachment security and childhood trauma. MethodsIn this cross-sectional study, we examined 38 patients with active major depression free of dyslipidemia, diabetes mellitus, hypertension, and obesity and 32 healthy controls. All participants underwent blood tests, psychometric assessments, and AS measurements using the Mobil-O-Graph arteriograph system. AS severity was evaluated using an augmentation index (AIx) normalized to 75 beats/min. ResultsIn the absence of defined clinical cardiovascular risk factors, there was no significant difference in AIx between individuals with depression and healthy controls (p = .75). Patients with longer intervals between depressive episodes had lower AIx (r = −0.44, p < .01). Insecure attachment and childhood trauma did not significantly associate with AIx in patients. Whereas insecure attachment was positively correlated with AIx only in healthy controls (r = 0.50, p = 01). ConclusionsOur analysis of established risk factors for atherosclerosis revealed that depression and childhood trauma had no significant relationship with AS. However, we did identify a novel finding: insecure attachment was significantly associated with AS severity in healthy adults without defined cardiovascular risk factors for the first time. To our knowledge, this is the first study to demonstrate this relationship.

Handgrip strength is inversely associated with augmentation index in patients with type 2 diabetes

Handgrip strength (HGS) is a measure of overall skeletal muscle strength and is used to identify risks for cardiovascular disease and mortality. Furthermore, HGS is an indicator of arterial stiffness that leads to atherosclerotic cardiovascular disease. This study aimed to examine the relationship between HGS and augmentation index (AIx) in patients with type 2 diabetes. A cross-sectional study was conducted to examine patients with type 2 diabetes whose HGS and AIx were measured in our hospital. AIx was measured noninvasively using an applanation tonometer, and multiple regression analyses were conducted to assess the independent relationship between HGS and AIx. This study included 404 patients. After adjusting for age, gender, body mass index, duration of diabetes, smoking and exercise habit, biochemical parameters, and physiological parameters related to arterial stiffness, HGS was found to be independently and inversely associated with AIx (β = − 0.270, p = 0.006). HGS was independently and inversely associated with AIx in patients with type 2 diabetes. Patients with diminished HGS should be subjected to intensive exercise therapy for reducing the risk of arterial stiffness and cardiovascular disease.Trial registration: UMIN000023010.

Augmentation Index in Patients with Thoracic Aortic Aneurysm: A Matched Case-Control Study.

Thoracic aortic aneurysms (TAA) may be associated with complications such as rupture and dissection, which can lead to a fatal outcome. Increased central arterial stiffness has been proposed to be present in patients with TAA compared to unmatched controls. We aimed to assess whether wall properties in patients with TAA are also altered when compared to a matched control group. Applanation tonometry was performed in 74 adults with TAA and 74 sex, age, weight, height, and left ventricular ejection fraction matched controls. Subsequently analysis of the pulse wave was done using the SphygmoCor System. For comparing the two groups, AIx was adjusted to a heart rate of 75/min (AIx@75). 148 1-to-1 matched participants were included in the final model. There was no significant difference in the Alx@75 between the TAA group and the matched control group [mean (SD) of 24.7 (11.2) % and 22.8 (11.2) %, p = 0.240]. Adjusted for known cardiovascular risk factors, there was no association between TAA and AIx@75. Patients with TAA showed comparable arterial wall properties to cardiovascular risk factor matched controls. Since higher arterial stiffness is associated with TAA progression, it remains to be investigated if increased central arterial stiffness is a relevant factor of TAA emergence.

Relationship of arterial tonometry and exercise in patients with chronic heart failure: a systematic review with meta-analysis and trial sequential analysis

BackgroundArterial stiffness is a common characteristic in patients with chronic heart failure (CHF), and arterial tonometric technologies related to arterial stiffness are novel and effective methods and have an important value in the diagnosis and prognosis of CHF. In terms of ameliorating arterial stiffness in patients with CHF, exercise training is considered an adjuvant treatment and also an effective means in the diagnosis and judgment of prognosis. However, there are huge controversies and inconsistencies in these aspects. The objective of this meta-analysis was to systematically test the connection of arterial tonometry and exercise in patients with CHF.MethodsDatabases, including MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, were accessed from inception to 7 March 2022. The meta-analysis was then conducted, and trial sequential analysis (TSA) was performed jointly to further verify our tests and reach more convincing conclusions by using RevMan version 5.4 software, STATA version 16.0 software, and TSA version 0.9.5.10 Beta software.ResultsEighteen articles were included, with a total of 876 participants satisfying the inclusion criteria. The pooling revealed that flow-mediated dilation (FMD) was lower in basal condition [standardized mean difference (SMD): − 2.28%, 95% confidence interval (CI) − 3.47 to − 1.08, P < 0.001] and improved significantly after exercise (SMD: 5.96%, 95% CI 2.81 to 9.05, P < 0.001) in patients with heart failure with reduced ejection fraction (HFrEF) compared with healthy participants. The high-intensity training exercise was more beneficial (SMD: 2.88%, 95% CI 1.78 to 3.97, P < 0.001) than the moderate-intensity training exercise to improve FMD in patients with CHF. For augmentation index (AIx), our study indicated no significant differences (SMD: 0.50%, 95% CI − 0.05 to 1.05, P = 0.074) in patients with heart failure with preserved ejection fraction (HFpEF) compared with healthy participants. However, other outcomes of our study were not identified after further verification using TSA, and more high-quality studies are needed to reach definitive conclusions in the future.ConclusionsThis review shows that FMD is lower in basal condition and improves significantly after exercise in patients with HFrEF compared with healthy population; high-intensity training exercise is more beneficial than moderate-intensity training exercise to improve FMD in patients with CHF; besides, there are no significant differences in AIx in patients with HFpEF compared with the healthy population. More high-quality studies on this topic are warranted.

Cerebral Augmentation Effect Induced by External Counterpulsation Is Not Related to Impaired Dynamic Cerebral Autoregulation in Ischemic Stroke.

Background and PurposeDynamic cerebral autoregulation is impaired after ischemic stroke. External counterpulsation (ECP) augments the cerebral blood flow of patients with ischemic stroke by elevation of blood pressure (BP). We aimed to investigate if cerebral augmentation effects during ECP were associated with impaired dynamic cerebral autoregulation in patients after acute ischemic stroke.MethodsForty patients with unilateral ischemic stroke and large artery atherosclerosis in the anterior circulation territory within 7 days from symptom onset and eighteen healthy controls were recruited. We monitored changes in mean flow velocity over both middle cerebral arteries (MCA) by transcranial Doppler (TCD) before, during, and immediately after ECP. Cerebral augmentation index was MCA mean flow velocity increase in percentage during ECP compared with baseline to evaluate the augmentation effects of ECP. Spontaneous arterial BP and cerebral blood flow velocity in both bilateral MCAs were recorded using a servo-controlled plethysmograph and TCD, respectively. Transfer function analysis was used to derive the autoregulatory parameters, including phase difference (PD), and gain.ResultsThe cerebral augmentation index in patients with stroke was significantly higher on both the ipsilateral and contralateral sides than that in controls, while the PD in patients with stroke was significantly lower on both sides than those in controls (all P < 0.05). The cerebral augmentation index did not correlate with PD and gain on either the ipsilateral or contralateral side of patients with stroke or in controls (all P > 0.05). The cerebral augmentation index of patients with stroke was significantly related to mean BP change on the ipsilateral side (R2 = 0.108, P = 0.038).ConclusionThe degree of ECP-induced cerebral augmentation effects as measured by the cerebral augmentation index did not correlate with the magnitude of impaired dynamic cerebral autoregulation.

Relationship Between Serum Cystatin C and Early Indicators of Arteriosclerosis in Hypertensive Patients with Normal Renal Function

Abstract Background To explore the relationship between serum cystatin C (CysC) and arteriosclerotic indicators such as brachial ankle pulse wave velocity (baPWV), carotid femoral pulse wave velocity (cfPWV), ankle brachial index (ABI), and augmentation index (AIx) in hypertensive patients with normal renal function. Methods From January 2017 to May 2019, 2,486 hypertensive patients with normal renal function were recruited and grouped according to CysC quartile, age, blood pressure, and whether or not taking antihypertensive drugs. Analysis of variance, χ2 test, Pearson correlation, and multivariate logistic regression analysis were used to clarify the relationship between CysC and arteriosclerosis indicators. Results As CysC levels increased, the incidence of baPWV ≥1.4 m/s and cfPWV &amp;gt;10 m/s increased gradually (P &amp;lt; 0.05). With increasing age and blood pressure classification, the incidence of baPWV ≥1.4 m/s and cfPWV &amp;gt;10 m/s as well as ABI and AIx gradually increased (P &amp;lt; 0.05). The incidence of cfPWV &amp;gt;10 m/s and AIx in patients taking antihypertensive drugs were higher than those in patients not taking antihypertensive drugs (P &amp;lt; 0.05). Pearson correlation analysis showed that CysC was weakly correlated with baPWV and cfPWV (r = 0.334, 0.283, P &amp;lt; 0.05), and had no significant correlation with ABI and AIx (r = 0.013, −0.005, P &amp;gt; 0.05). After adjusting for various factors, the multivariate logistic regression analysis showed that compared with quartile 1 CysC patients, odds ratio (OR) (95% confidence interval [CI]) of baPWV ≥1.4 m/s in quartile 4 group was 2.51 (1.47–4.31) while OR (95% CI) of cfPWV &amp;gt;10 m/s in quartile 2, 3, and 4 groups were 1.60 (1.03–2.48), 1.96 (1.25–3.08), and 2.11 (1.30–3.43), respectively. For per standard deviation increase of CysC, the OR (95% CI) of baPWV ≥1.4 m/s and cfPWV &amp;gt;10 m/s were 1.25(1.04–1.51) and 1.31 (1.10–1.56), respectively. Conclusions CysC is an independent predictor of increased baPWV and cfPWV in hypertensive patients with normal renal function.

Augmentation index in patients with different stages of hypertension

Aim. To assess the augmentation index (AIx) in hypertensive patients depending on stages of hypertension (HTN). Material and methods. Eighty-three people were examined: 62 patients with HTN and 21 patients of the control group. The subjects underwent a carotid duplex ultrasound and photoplethysmography to determine AIx. The results were processed using Statistica 10.0 software. Results. Patients with HT were divided into 3 groups: stage I HTN (n=23); stage II HTN (n=18); stage III HTN (n=21). AIx was significantly higher in all groups of hypertensive patients compared to the control group. AIx levels were higher in the groups with a higher stage of HTN. Correlations were found between AIx and intima-media thickness (IMT) (r=0,676, p 18,5% (sensitivity, 85,4%; specificity, 53%). Conclusion. With an increase in HTN stage, Alx significantly increases and directly correlates with IMT, the presence and amount of ASP, and the carotid stenosis percentage. The Alx level is influenced by age, IMT and the presence of ASP. ROC-analysis revealed the threshold values of Alx for each stage of hypertension.

Increased augmentation index in patients with Ehlers-Danlos syndrome

BackgroundEhlers-Danlos Syndrome (EDS) comprises a heterogeneous group of diseases characterized by joint hypermobility, connective tissue friability, and vascular fragility. Reliable prognostic factors predicting vascular disease progression (e.g. arterial aneurysms, dissections, and ruptures) in EDS patients are still missing. Recently, applanation tonometry derived augmentation index (AIx), an indirect marker of arterial stiffness, has shown to be positively associated with progression of aortic disease in Marfan syndrome. In this study, we assessed aortic AIx in patients with EDS and matched healthy controls.MethodsWe performed noninvasive applanation tonometry in 61 adults with EDS (43 women and 18 men aged 39.3 ± 14.6 years) and 61 age-, gender-, height-, and weight-matched healthy controls. Radial artery pulse waveforms were recorded and analyzed using the SphygmoCor System (AtCor Medical, Sydney, NSW, Australia). Calculated AIx was adjusted to a heart rate of 75/min. Groups were compared and association between AIx and EDS was determined by univariate and multivariate regression analysis.ResultsEDS patients were categorized in classical type EDS (34%), hypermobile type EDS (43%), vascular type EDS (5%), or remained unassignable (18%) due to overlapping features. EDS patients showed a significantly increased aortic AIx compared to healthy controls (22.8% ± 10.1 vs 14.8% ± 14.0, p < 0.001). EDS showed a positive association with AIx; independent of age, sex, height, blood pressure, medication, and pack years of smoking.ConclusionsPatients with EDS showed elevated AIx, indicating increased arterial stiffness when compared to healthy controls. Further investigations are needed in order to assess the prognostic value of increased AIx for cardiovascular outcomes in patients with EDS.

Endovascular Revascularization Improves the Central Hemodynamics and Augmentation Index in Patients with Peripheral Artery Disease.

Objective To evaluate the effect of endovascular therapy (EVT) on the central blood pressure (CBP) and augmentation index (AIx) in patients with peripheral artery disease (PAD). Methods The CBP and AIx were assessed by radial applanation tonometry the day before and the day after EVT. We compared the differences in the therapeutic effects between the stenotic and occlusive lesions and between the iliac and superficial femoral artery (SFA) lesions. Patients We enrolled 60 consecutive patients with PAD who underwent EVT for de novo lesions. Results Both the CBP and AIx were significantly decreased after EVT (125±22 mmHg to 112±22 mmHg; p=0.002 and 84%±16% to 73%±15%; p<0.001, respectively). The effects of EVT on the CBP and AIx were equivalent, regardless of whether the target lesion was the stenotic lesion or the occlusive lesion. There were no significant differences between the iliac and SFA lesions in the effects of EVT on the CBP and AIx. Conclusion EVT improved the CBP and AIx in patients with PAD, regardless of the morphology or site of the lesions.

The serum sclerostin level is positively associated with the aortic augmentation index in patients on peritoneal dialysis.

Objective:Sclerostin is a canonical Wingless (Wnt)/β-catenin signaling pathway inhibitor and had been associated with high arterial stiffness in patients with chronic kidney disease. The aortic augmentation index (AIx), a noninvasive method of assessing central hemodynamics/wave reflections, has been widely used as a clinical index of arterial stiffness. The aim of this study was to evaluate the relationship between fasting serum sclerostin levels and AIx values in peritoneal dialysis (PD) patients.Materials and Methods:Fasting blood samples were obtained from 75 PD patients. The aortic AIx value was measured using a validated tonometry system (SphygmoCor, AtCor Medical, Sydney, New South Wales, Australia). Serum sclerostin and dickkopf-1 (DKK1) levels were quantified using commercial enzyme-linked immunosorbent assay kits.Results:Women PD patients had higher aortic AIx values than men (P = 0.039), while lower aortic AIx values were found in PD patients who used statins (P = 0.004). Univariate linear analysis of the aortic AIx values in PD patients showed that systolic blood pressure (P = 0.001), diastolic blood pressure (P = 0.018), and serum sclerostin levels (P = 0.001) were positively correlated, while height (P = 0.018), body weight (P = 0.001), body mass index (P = 0.043), and weekly total creatinine clearance (P = 0.015) were negatively correlated with aortic AIx values in PD patients. Multivariate linear regression analysis of the factors significantly associated with the aortic AIx values showed that serum sclerostin levels (adjusted R2 = 0.057, P = 0.011) and systolic blood pressure (adjusted R2 = 0.125, P = 0.004) were positively associated, while body weight (adjusted R2 = 0.113, P = 0.002) was inversely associated with aortic AIx values in PD patients.Conclusion:In this study, the serum sclerostin level, but not DKK1, was positively associated with aortic AIx values in PD patients.

Effect of amyloidosis and proteinuria on augmentation index in patients with familial mediterranean fever

Aim: There is a common belief that creativity and artistic talent/creativity are related to psychopathology. Mood disorders are more prominent in studies about relations between creativity and psychopathology. Also patients may be more productive during mania and hypomania periods of bipolar mood disorder. Considering these data, the purpose of this study was to investigate whether there is a predisposition to bipolar disorder in people with artistic creativity. Materials and Methods: A total of 157 students were selected randomly from the Art department and 157 from different departments including Faculties of Law, Science and Literature and Education. Art students had proven their artistic competence by two stage examination. Groups were compared based on mood disorder questionnaire (MDQ) and bipolarity predisposition factors. SPSS 22.0 was used for statistical analyses. Chi-square analysis was used to compare case-control groups according to demographic characteristics.Results: There were no significant differences between the groups in terms of age, sex, education, smoking, marital status, family history of psychiatric disorder. The number of psychiatric admissions were higher in the students of art (p=0.026). Alcohol-substance use was higher among students of Art (p=0.001). The MDQ scale result was 50.3% positive for Art students and 26.8% positive for students from different departments. MDQ scale, the predisposition of bipolar disorder was found to be significantly higher in Art students.Conclusion: The high prevalence of bipolarity features with MDQ scale in art students supports the relationship between artistic talent / creativity and bipolar disorder.

Evaluation of Arterial Stiffness Using Pulse Wave Velocity and Augmentation Index in Patients with Chronic Venous Insufficiency.

Background and Objectives Chronic venous insufficiency (CVI) is a common pathology of the circulatory system and is associated with a high morbidity for the patients and causes high costs for the healthcare systems. Arterial stiffness has been shown to be a predictor of cardiovascular events and mortality. The relationship between CVI and arterial stiffness using pulse wave velocity (PWV) and augmentation index (Aix) was evaluated in this study. Methods Sixty-two patients with the stage of C3-C5 chronic venous disease (CVD) and 48 healthy subjects were enrolled in the study. To assess arterial stiffness, all cases were evaluated with I.E.M. Mobil-O-Graph brand ambulatory blood pressure monitor device. PWV and Aix were used to assess arterial stiffness in this study. Results The mean age was 61.9±11.05 years and 54 % of the patient population was females. PWV and Aix were significantly higher in CVI patients than controls (8.92±1.65 vs. 8.03±1.43, p=0.001; 25.51±8.14 vs. 20.15±9.49, p=0.003, respectively) and also positive linear correlation was observed between CVI and all measured arterial stiffness parameters (r=0.675 for CVI and PWV, r=0.659 for CVI and Aix, respectively). A PWV value of > 9.2 has 88.9 % sensitivity and 71.4 % specificity to predict the presence of CVI. Conclusions PWV and Aix are the most commonly used, easy, reproducible, reliable methods in the clinic to assess arterial stiffness. Logistic regression analysis showed that PWV and Aix were the independent predictors of CVI. PWV has the sensitivity of 88.9 % and specificity of 71.4 % to detect the presence of CVI.

Positive correlation of the serum angiopoietin-like protein 3 levels with the aortic augmentation index in patients with coronary artery disease.

PurposeAngiopoietin-like protein 3 (ANGPTL3) plays an important role in lipid metabolism and angiogenesis and is elevated in familial hypercholesterolemia, metabolic syndrome, and insulin resistance. This study aims to evaluate the relationship between the fasting serum ANGPTL3 levels and the aortic augmentation index (AIx) in patients with coronary artery disease (CAD).Materials and methodsFasting blood samples were obtained from 100 patients with CAD. The AIx was measured using a validated tonometry system (SphygmoCor). The serum ANGPTL3 levels were assessed using a commercial enzyme-linked immunosorbent assay kit.ResultsThe aortic AIx values were higher in female patients with CAD (P=0.003) than those in male patients with CAD. The univariate linear analysis of the aortic AIx values reveals that the height (r=−0.363; P<0.001) and body weight (r=−0.350; P<0.001) were negatively correlated, whereas the age (r=0.202; P=0.044) and logarithmically transformed ANGPTL3 (log-ANGPTL3, r=0.357; P<0.001) were positively correlated with the aortic AIx values in patients with CAD. The multivariate forward stepwise linear regression analysis of the factors significantly associated with the aortic AIx revealed that the height (β=−0.269; adjusted R2 change=0.123; P=0.007) and serum log-ANGPTL3 level (β=0.259; adjusted R2 change=0.051; P=0.010) were independent predictors of the aortic AIx values in patients with CAD.ConclusionThe fasting serum ANGPTL3 level positively correlated with the aortic AIx values among patients with CAD.

Assessment of Vascular Stiffness in Normotensive Patients With Familial Hypercholesterolemia

to analyze parameters of vascular stiffness and augmentation index in patients with familial hypercholesterolemia (FH). We compared parameters of vascular stiffness of 88 normotensive FH patients (mean age 41.95±1.43 years, 43 men [48.9 %]) and 68 subjects with normal blood lipid spectrum (mean age 37.58±1.02 years, 21 men [30.9 %]). FH was diagnosed according to the criteria of the Dutch Lipid Clinic Network. Examination included lipid profile, 24‑hour blood pressure (BP) monitoring with assessment of arterial stiffness. Normotensive FH patients had higher pulse wave velocity (PWV) (7.99±0.17 m/s) in comparison with patients with normal lipid spectrum (6.87±0.10 m/s), p.

POSSIBILITY OF USING THE AUGMENTATION INDEX AS A PREDICTOR OF ATHEROSCLEROTIC DISEASE OF CAROTID ARTERIES IN PATIENTS WITH ESSENTIAL HYPERTENSION

Objective. Study of the possibility of predicting atherosclerosis of carotid arteries on the basis of the augmentation index in patients with essential hypertension.Material and methods. A total of 155 patients with EH in the age range 30-70 years. A physical examination, identification of a number of biochemical parameters: glucose and creatinine and blood lipid (LDL, HDL and triglycerides), duplex scanning of carotid arteries, the definition of arterial stiffness by pulse wave contour analysis.Results. The augmentation index, along with age, was an independent risk factor for atherosclerosis carotid arteries in patients with EH, as well as the severity of its symptoms.

Tetrahydrobiopterin lowers muscle sympathetic nerve activity and improves augmentation index in patients with chronic kidney disease.

Chronic kidney disease (CKD) is characterized by overactivation of the sympathetic nervous system (SNS) that contributes to cardiovascular risk. Decreased nitric oxide (NO) bioavailability is a major factor contributing to SNS overactivity in CKD, since reduced neuronal NO leads to increased central SNS activity. Tetrahydrobiopterin (BH4) is an essential cofactor for nitric oxide synthase that increases NO bioavailability in experimental models of CKD. We conducted a randomized, double-blinded, placebo-controlled trial testing the benefits of oral sapropterin dihydrochloride (6R-BH4, a synthetic form of BH4) in CKD. 36 patients with CKD and hypertension were randomized to 12 wk of 1) 200 mg 6R-BH4 twice daily + 1 mg folic acid once daily; vs. 2) placebo + folic acid. The primary endpoint was a change in resting muscle sympathetic nerve activity (MSNA). Secondary endpoints included arterial stiffness using pulse wave velocity (PWV) and augmentation index (AIx), endothelial function using brachial artery flow-mediated dilation and endothelial progenitor cells, endothelium-independent vasodilatation (EID), microalbuminuria, and blood pressure. We observed a significant reduction in MSNA after 12 wk of 6R-BH4 (-7.5 ± 2.1 bursts/min vs. +3.2 ± 1.3 bursts/min; P = 0.003). We also observed a significant improvement in AIx (by -5.8 ± 2.0% vs. +1.8 ± 1.7 in the placebo group, P = 0.007). EID increased significantly (by +2.0 ± 0.59%; P = 0.004) in the 6R-BH4 group, but there was no change in endothelial function. There was a trend toward a reduction in diastolic blood pressure by -4 ± 3 mmHg at 12 wk with 6R-BH4 (P = 0.055). 6R-BH4 treatment may have beneficial effects on SNS activity and central pulse wave reflections in hypertensive patients with CKD.

Aortic augmentation index in patients with peripheral arterial disease.

Aortic augmentation index (AIx) is used to investigate arterial stiffness. The authors tested the hypothesis that patients with peripheral arterial disease (PAD) demonstrate a higher AIx and also evaluated several related factors. In 97 patients with PAD, identified by ankle-brachial pressure index (ABPI ≤ 0.9), and 97 controls (ABPI ≥ 0.91< 1.4), AIx (%) was determined using tonometry of the radial artery. There was no significant difference between patients and controls in characteristics of age, sex, height, diastolic blood pressure, mean blood pressure, and heart rate. AIx was higher in patients with PAD (32 ± 9 vs 28 ± 9; P = .001). In multivariate regression analysis, AIx was independently associated with heart rate (β = -0.40, P = .0005). This study showed that AIx increased in patients with PAD and that heart rate is a determinant of AIx. Further studies are necessary to assess the pathophysiological and clinical importance of AIx in patients with PAD.

Effect of age and Blood Pressure on Surrogate Markers of Atherosclerosis in Patients with Type 2 Diabetes Mellitus.

Increased arterial stiffness may be an important path- way linking diabetes mellitus to increased cardiovascular risk. The study was conducted to assess the surrogate markers of arterial stiffness in patients with Type 2 diabetes mellitus (T2DM), and compare with age-matched hypertensive and healthy controls. Also the effect of age and blood pressure on these markers was evaluated. This cross-sectional study was carried out at a tertiary care hospital in West India. After a detailed medical history and anthropometric evaluation, all the participants were subjected to measurements of Arterial Stiffness Index (ASI), Pulse Wave Velocity (PWV), and Augmentation Index (AIx) using a non-invasive oscillometric method. The four study groups consisted of patients with T2DM (>5 years) along with hypertension, newly diagnosed patients with T2DM (<2years) without hypertension, hypertensive controls, and healthy controls. PWV, ASI, AIx were elevated in patients with T2DM compared to healthy controls (p<0.05). Patients with T2DM above 60 years had higher carotid-femoral PWV, ASI and AIx than those below 60 years (p<0.05). ASI and AIx were significantly increased in patients with T2DM with hypertension having systolic BP > 140 mmHg compared to those with systolic BP < 140 mmHg. A very strong correlation between PWV and AIx in patients with T2DM and hypertensive controls was observed. This study reveals that markers of arterial stiffness (PWV, ASI, AIx) were increased significantly in patients with T2DM compared to healthy controls. Age and systolic blood pressure had significant influence on these markers. Thus, oscillometric markers have potential utility in identifying subclinical atherosclerosis in patients with T2DM.

Renal nerve ablation reduces augmentation index in patients with resistant hypertension

Renal denervation (RDN) has been demonstrated to reduce muscle sympathetic nerve activity (MSNA) and blood pressure (BP) in patients with resistant hypertension. Whether alterations of arterial stiffness may contribute to BP-lowering effects of RDN is unknown. We measured office BP and arterial stiffness using fingertip tonometry-derived augmentation index (EndoPAT2000) at baseline and at 3-month follow-up in 50 consecutive patients with resistant hypertension. Forty patients received RDN and 10 patients served as controls. MSNA was obtained in 20 RDN and 10 non-RDN patients. Baseline BP averaged 170/92 ± 19/15 mmHg (RDN) and 171/93 ± 14/8 mmHg (non-RDN) despite the use of 4.9 ± 1.9 and 4.4 ± 2.0 antihypertensive drugs, respectively. RDN significantly reduced SBP (170 ± 19 vs. 154 ± 25 mmHg; P < 0.001) and DBP (92 ± 15 vs. 84 ± 16 mmHg; P<0.001), augmentation index (30.6 ± 23.8 vs. 22.7 ± 22.4%; P=0.002), AI@75 corrected for heart rate (22.4 ± 21.6 vs. 14.4 ± 20.7; P=0.002) and MSNA (80 ± 15 vs. 71 ± 18 bursts/100 heartbeats; P<0.01). Changes in AI@75 with RDN were unrelated to SBP (r=0.043; P = 0.79), and DBP (r = 0.092; P = 0.57) and MSNA changes (r = -0.17; P = 0.49). No changes in BP, augmentation index, AI@75 or MSNA were observed in the non-RDN group. RDN results in a substantial and rapid reduction in augmentation index, which appears to be independent of BP and MSNA changes. These findings are indicative of a beneficial effect of RDN on arterial stiffness in patients with resistant hypertension and may contribute to the sustained BP-lowering effect of RDN.