Reactive Hyperemia Peripheral Arterial Tonometry Research Articles

Pre-procedural peripheral endothelial function is associated with increased serum creatinine following percutaneous coronary procedure in stable patients with a preserved estimated glomerular filtration rate

BackgroundWorsening renal function, indicated by increased serum creatinine (SCr), is a common complication of percutaneous coronary procedures. Risk factors for increased SCr overlap with coronary risk factors involved in endothelial dysfunction. We hypothesized that endothelial dysfunction, measured using the reactive hyperemia peripheral arterial tonometry index (RHI), can predict periprocedure-increased SCr. MethodsRHI was assessed before elective coronary procedures in 316 consecutive stable patients with a preserved estimated glomerular filtration rate (eGFR, >60mL/min/1.73m2). SCr was measured before and 2 days after procedures. ResultsThere was no significant correlation between natural logarithmic transformations of RHI (Ln-RHI) and basal Ln-eGFR. Periprocedure increase in SCr was observed in 148 (47%) patients. The increased SCr group had significantly lower Ln-RHI [0.48 (0.36, 0.62) vs. 0.59 (0.49, 0.76), p<0.001]. Multivariate linear regression analysis identified body mass index (BMI) (β=0.148, p=0.005) and Ln-RHI (β=−0.365, p<0.001) as significant determinants of percent changes in SCr. Multivariate logistic regression analysis identified Ln-RHI (per 0.1) [odds ratio (OR) 0.672, 95% confidence interval (95% CI) 0.586–0.722; p<0.001], Ln-B-type natriuretic peptide (OR: 1.484, 95% CI: 1.130–1.974; p=0.004), current smoking (OR: 2.563, 95% CI: 1.379–4.763, p=0.003), BMI (OR: 1.113, 95% CI: 1.031–1.203; p=0.007), coronary intervention (OR: 1.736, 95% CI: 1.036–2.909; p=0.036), and Ln-hemoglobin A1c (OR: 6.728, 95% CI: 1.093–41.392, p=0.040) as independent determinants of increased SCr. Receiver-operating characteristics curve analysis showed that Ln-RHI correlated significantly with increased SCr (area under the curve, 0.684, 95% CI: 0.626–0.742, p<0.001). The optimum cut-off point of Ln-RHI for the periprocedure increased SCr was 0.545. ConclusionsPre-procedure measurement of endothelial function by RHI is an effective strategy to assess the patient's risk conditions for worsening renal function after percutaneous coronary procedures.

Lenvatinib, an oral multi-kinases inhibitor, -associated hypertension: Potential role of vascular endothelial dysfunction

Background and aimsLenvatinib (Lenvima®), an oral multi-kinase inhibitor, is effective in the treatment of differentiated thyroid carcinomas (DTCs). A severe adverse effect of lenvatinib is hypertension, thus limiting its use as an anti-cancer treatment. Although the pathogenesis of hypertension is generally assumed to involve microvascular bed reduction and an increase in peripheral vascular resistance due to a decrease in nitrogen oxide (NOx) production after vascular endothelial growth factor (VEGF) inhibition, the effects of hypertension on vascular endothelial function in actual patients remain unclear. Here, we examined how lenvatinib affects vascular endothelial function. MethodsTen consecutive DTC patients who did not take any cardiovascular agents were orally administered 24 mg of lenvatinib once daily. Using an EndoPAT2000® system, we used reactive hyperemia-peripheral arterial tonometry (RH-PAT) and evaluated vascular endothelial function on the basis of the RH-PAT index (RHI). We expressed the results as %RHI, which indicates the change compared with pretreatment levels. Additionally, we measured serum NOx and plasma VEGF concentrations pre- and post-treatment. ResultsAll of the patients treated with lenvatinib exhibited significant hypertension; the %RHI levels were significantly decreased the day after treatment with lenvatinib. Furthermore, serum NOx and plasma VEGF concentrations were significantly decreased and increased, respectively, compared with pretreatment levels. These results indicate that hypertension induced by lenvatinib may be caused by a decrease in nitric oxide production, as a result of VEGF inhibition and impaired vascular endothelial function. ConclusionsWe provide the first demonstration that lenvatinib causes hypertension via vascular endothelial dysfunction in human subjects.

Resveratrol Improves Vascular Function and Mitochondrial Number but Not Glucose Metabolism in Older Adults.

Resveratrol, a plant-derived polyphenol, has been reported to improve glucose metabolism and vascular function and to extend life span in animal models, but studies in humans have been inconclusive. In a randomized, double-blind crossover study, we treated older glucose-intolerant adults (n = 30) with resveratrol (2-3 g/daily) or placebo, each for 6 weeks. A standard mixed-meal test was used to assess insulin sensitivity (Matsuda index) and secretion (C-peptide deconvolution) and vascular function by reactive hyperemia peripheral arterial tonometry. Skeletal muscle samples were obtained for gene expression using RNA-Seq analysis and to assess mitochondrial morphology. There were no changes in glucose tolerance, insulin sensitivity, weight, blood pressure, or lipid profile following resveratrol treatment. Fasting reactive hyperemia index improved with resveratrol (2.02 ± 0.2 vs 1.76 ± 0.02, p = .002). RNA-Seq analysis yielded 140 differentially expressed transcripts (corrected p-value ≤ .05), predominantly associated with mitochondrial genes and noncoding RNA. Ingenuity Pathway Analysis confirmed that mitochondrial dysfunction (p = 2.77 × 10-12) and oxidative phosphorylation (p = 1.41 × 10-11) were the most significantly perturbed pathways. Mitochondrial number, but not size, was increased. Resveratrol treatment of older adults with impaired glucose regulation may have beneficial effects on vascular function, but not glucose metabolism or insulin sensitivity. Changes in gene expression suggest effects similar to those observed with caloric restriction, which has been shown to increase life and health span in animal models, although its significance for humans is uncertain. Future human studies should address the appropriate dose range and low bioavailability of resveratrol.

Evaluation of a static stretching intervention on vascular endothelial function and arterial stiffness

Purpose: Maintenance and enhancement of vascular endothelial function contribute to the prevention of cardiovascular disease and prolong a healthy life expectancy. Given the reversible nature of vascular endothelial function, interventions to improve this function might prevent arteriosclerosis. Accordingly, we studied the effects of a 6-month static stretching intervention on vascular endothelial function (reactive hyperaemia peripheral arterial tonometry index: RH-PAT index) and arterial stiffness (brachial-ankle pulse wave velocity: baPWV) and investigated the reversibility of these effects after a 6-month detraining period following intervention completion. Methods: The study evaluated 22 healthy, non-smoking, premenopausal women aged ≥40 years. Subjects were randomly assigned to the full-intervention (n = 11; mean age: 48.6 ± 2.8 years) or a half-intervention that included a control period (n = 11; mean age: 46.9 ± 3.6 years). Results: Body flexibility and vascular endothelial function improved significantly after 3 months of static stretching. In addition to these improvements, arterial stiffness improved significantly after a 6-month intervention. However, after a 6-month detraining period, vascular endothelial function, flexibility, and arterial stiffness all returned to preintervention conditions, demonstrating the reversibility of the obtained effects. Conclusion: A 3-month static stretching intervention was found to improve vascular endothelial function, and an additional 3-month intervention also improved arterial stiffness. However, these effects were reversed by detraining.

Stretching Exercises Improve Vascular Endothelial Dysfunction Through Attenuation of Oxidative Stress in Chronic Heart Failure Patients With an Implantable Cardioverter Defibrillator.

Endurance training improves oxidative stress and vascular endothelial dysfunction in patients with chronic heart failure (CHF). However, patients with CHF and an implantable cardioverter defibrillator (ICD) or cardiac resynchronization therapy-defibrillator (CRT-D) often avoid endurance training for fear of ICD shock. Recent studies have reported that stretching exercises enhance antioxidant activity and improve vascular responses. Therefore, we aimed to assess the effects of 4 weeks of stretching exercises on oxidative stress and vascular endothelial function in patients with CHF with an ICD or CRT-D. Fifty sedentary patients with CHF (78% males; mean age = 70 ± 9 years; left ventricular ejection fraction = 26% ± 8%) with an ICD or CRT-D were randomly divided into a group that performed 4 weeks of stretching exercises (stretching group) and a group that continued a sedentary lifestyle (control group). We compared the reactive hyperemia peripheral arterial tonometry (RH-PAT) index and blood parameters, such as von Willebrand factor (vWF), malondialdehyde-modified low-density lipoprotein cholesterol (MDA-LDL), reactive oxygen species (ROS), high-sensitivity C-reactive protein, pentraxin 3, and fibrinogen between the 2 groups before and after the 4-week study period. In the stretching group, a significant increase in the RH-PAT index and significant decreases in vWF, MDA-LDL, ROS, and fibrinogen concentrations were observed after the study compared with before (all P < .05). No significant changes were observed in the control group. Four weeks of stretching exercises improved vascular endothelial dysfunction through attenuation of oxidative stress in sedentary patients with CHF with an ICD or CRT-D.

Endothelial function after ST-elevation myocardial infarction in patients with high levels of high-sensitivity CRP and Lp-PLA2: A substudy of the RESPONSE randomized trial.

The combination of high levels of high-sensitive C-reactive protein (hs-CRP) and lipoprotein-associated phospholipase-A2 (Lp-PLA2) was recently shown to correlate with increased cardiovascular risk. Endothelial dysfunction is also known to be a risk factor for cardiovascular events. To test among patients with previous ST-elevation myocardial infarction (STEMI) the hypothesis that high levels of both hs-CRP and Lp-PLA2 may be associated with impaired endothelium-dependent vasodilatation. In this substudy of the RESPONSE randomized trial, we used reactive hyperemia peripheral artery tonometry (RH-PAT) 4 to 6weeks after STEMI and primary percutaneous coronary intervention (PPCI) to non-invasively assess endothelial function (RH-PAT index <1.67 identified endothelial dysfunction). Reliable measurements of RH-PAT, hs-CRP, and Lp-PLA2 were obtained in 68 patients, who were classified as high-risk if levels of both hs-CRP and Lp-PLA2 were in the upper tertile (≥3.84mg/L and >239μg/L, respectively). Patients were 57.4±9.7years and 53 (77.9%) were men. 11 (16%) patients were classified as high-risk and 57 (84%) as low-to-intermediate-risk. The RH-PAT index was 1.68±0.22 in high-risk and 1.95±0.63 in low-to-intermediate-risk patients (p=0.17). Endothelial dysfunction was present in 8 (72.7%) high-risk and 26 (45.6%) low-to-intermediate-risk patients (p=0.09). Framingham risk score, NT-proBNP and fibrinogen levels were higher in high-risk patients (p≤0.03). In this population of patients with recent STEMI and PPCI, we observed between patients with high hs-CRP and Lp-PLA levels and all other patients no more than numerical differences in endothelial function that did not reach a statistical significance. Nevertheless, further research in larger study populations may be warranted.

Endothelial Function in Children and Adolescents Is Mainly Influenced by Age, Sex and Physical Activity ― An Analysis of Reactive Hyperemic Peripheral Artery Tonometry ―

As adolescents rarely experience cardiovascular events, surrogate markers of atherosclerosis are useful to justify and monitor effects of primary prevention and therapy of risk factors. Endothelial function assessed by reactive hyperemic peripheral arterial tonometry (RH-PAT) resulting in a reactive hyperemic index (RHI) is a noninvasive method with limited data for use in children and adolescents.Methods and Results:We performed a total of 931 RHI measurements in 445 high-school students, aged 10-17 years, over a time period of 5 years. Students were randomized by class to 60 min physical exercise (PE) at school daily (intervention group), or 2 units of 45-min PE weekly (control group). To characterize the factors influencing the RHI, anthropometry, cardiopulmonary exercise testing, blood cholesterol and quality of life were assessed and used to build mixed linear models. Main influential factors were age, with an increase of RHI from 1.53±0.42 in the youngest to 1.96±0.59 in the oldest students, sex, with higher values in girls, and physical activity. This increase adjusted by age and sex was estimated as 0.11 [0.08, 0.14] per year. RHI was higher in the intervention group by 0.09 [-0.05, 0.23] in comparison with the control group. If RH-PAT is used in research or as a clinical tool in adolescents, the shown age- and sex-dependence of RHI have to be taken in account.

Endothelial function and arterial stiffness indexes in subjects with acute ischemic stroke: Relationship with TOAST subtype

Background and aimsOnly one study has examined endothelial function in subjects with acute ischemic stroke and no study has yet assessed arterial stiffness and reactive hyperemia peripheral arterial tonometry (RH-PAT) in ischemic stroke and its clinical subtypes. Our study aimed to evaluate arterial stiffness and endothelial dysfunction indexes in patients with acute ischemic stroke and the relationship between endothelial dysfunction indexes and arterial stiffness markers and stroke subtypes according to Trial of Org 10172 in Acute Stroke Treatment (TOAST) Classification. MethodsWe enrolled 98 patients with a diagnosis of acute ischemic stroke and 105 hospitalized patients without a diagnosis of acute ischemic stroke. Arterial stiffness analysis was conducted by applanation tonometry to record radial artery pressure waveform continuously; augmentation index (Aix) and pulse wave velocity (PWV) were calculated. The reactive hyperemia index (RHI) was assessed by peripheral arterial tonometry. ResultsIn comparison to controls, ischemic stroke subjects had higher mean levels of PWV, Aix, and significantly lower mean RHI values. Compared to subjects with lacunar and cardioembolic stroke, those with Large Artery AtheroSclerosis (LAAS) subtype of stroke had higher median levels of PWV and significantly lower median levels of RHI. On multinomial logistic regression analysis of predictive variables of stroke subtype (lacunar vs. LAAS and lacunar vs. cardioembolic), we observed a negative association between RHI value and LAAS subtype and a negative association of PWV with cardioembolic subtype. ConclusionsOur findings underline the relationship between endothelial and arterial stiffness index correlations in patients with acute ischemic stroke, also suggesting the use of a combination of PAT and arterial stiffness indexes to better categorize patients with ischemic stroke.

Nitric Oxide-Dependent Endothelial Dysfunction and Reduced Arginine Bioavailability in Plasmodium vivax Malaria but No Greater Increase in Intravascular Hemolysis in Severe Disease.

Pathogenesis of severe Plasmodium vivax malaria is poorly understood. Endothelial dysfunction and reduced nitric oxide (NO) bioavailability characterize severe falciparum malaria, but have not been assessed in severe vivax malaria. In patients with severe vivax malaria (n = 9), patients with nonsevere vivax malaria (n = 58), and healthy controls (n = 79), we measured NO-dependent endothelial function by using reactive hyperemia-peripheral arterial tonometry (RH-PAT) and assessed associations with arginine, asymmetric dimethylarginine (ADMA), and hemolysis. The L-arginine level and the L-arginine to ADMA ratio (a measure of L-arginine bioavailability) were reduced in patients with severe vivax malaria and those with nonsevere vivax malaria, compared with healthy controls (median L-arginine level, 65, 66, and 98 µmol/mL, respectively [P = .0001]; median L-arginine to ADMA ratio, 115, 125, and 187, respectively [P = .0001]). Endothelial function was impaired in proportion to disease severity (median RH-PAT index, 1.49, 1.73, and 1.97 in patients with severe vivax malaria, those with nonsevere vivax malaria, and healthy controls, respectively; P = .018) and was associated with the L-arginine to ADMA ratio. While the posttreatment fall in hemoglobin level was greater in severe vivax malaria as compared to nonsevere vivax malaria (2.5 vs 1 g/dL; P = .0001), markers of intravascular hemolysis were not higher in severe disease. Endothelial function is impaired in nonsevere and severe vivax malaria, is associated with reduced L-arginine bioavailability, and may contribute to microvascular pathogenesis. Severe disease appears to be more associated with extravascular hemolysis than with intravascular hemolysis.

The effect of fresh versus standard blood transfusion on microvascular endothelial function

The duration of red blood cell (RBC) storage may have a negative impact on endothelial nitric oxide bioavailability. We tested the hypothesis that transfused fresh blood will have a more favorable effect on microvascular endothelial function as compared to older standard issue blood. Participants requiring chronic RBC transfusions were enrolled in a crossover design study to receive fresh (<7 days of storage) or standard (up to 42 days of storage) blood on 2 separate visits. Endothelial function was assessed by reactive hyperemia peripheral arterial tonometry that was measured before and after transfusions. For each participant, the difference between endothelial function pretransfusion and posttransfusion was assessed in relation to blood storage time. Twenty-one patients (71 ± 16 years, 52% females) were enrolled. Mean age of fresh blood was 5.5 days (±1.0), and that of standard blood was 24.5 days (±7.9 days). The pretransfusion hemoglobin was 83.1 ± 2.5 g/L; and posttransfusion, 98.9 ± 2.6 g/L. An average of 2 U of packed RBCs was transfused. Microvascular endothelial function decreased more frequently after transfusion of standard blood compared to fresh blood. Standard issue blood transfusion was associated with decrease in reactive hyperemia peripheral arterial tonometry index (-0.25 ± 0.63) compared to fresh blood (+0.03 ± 0.49); P = .026. Transfusions of standard issue blood are associated with less favorable effect on microvascular endothelial function as compared to fresh blood.

Prognostic significance of circulating leukocyte subtype counts in patients with coronary artery disease

Background and aimsThis study investigated the association of leukocyte subtype counts with vascular endothelial dysfunction and future cardiovascular events in patients with coronary artery disease (CAD). MethodsThe study included 389 consecutive CAD patients (259 male, 130 female; mean age, 70.1 ± 9.9 years). The patients underwent coronary angiography, and measurement of blood parameters, including leukocyte subtype counts. ResultsThere were 84 cardiovascular events during a mean follow-up of 586 ± 378 days. Kaplan–Meier analysis showed a higher probability of cardiovascular events in the high-monocyte group (≥360/mm3) compared with the low-monocyte group (<360/mm3) (log-rank test, p = 0.047). Multivariate Cox hazard analysis identified a high monocyte count as an independent predictor of cardiovascular events (hazard ratio: 1.63, 95% confidence interval:1.05–2.51, p = 0.028). Peripheral endothelial function in 355 of the CAD patients was assessed by reactive hyperemia peripheral arterial tonometry index (RHI) to examine the association of ln-RHI with leukocyte subtype counts. Total leukocyte, monocyte and neutrophil counts were significantly higher in CAD patients with low ln-RHI (<0.57: the mean ln-RHI value) compared with those with high ln-RHI (≥0.57). Univariate analyses revealed that ln-RHI in CAD patients was positively correlated with ln-total leukocyte (r = −0.187, p < 0.001), ln-monocyte (r = 0.316, p < 0.001), and neutrophil (r = −0.175, p = 0.001) counts. Multiple regression analysis showed that the monocyte count was a significant and independent factor associated with ln-RHI (adjusted R2 = 0.126, p < 0.001). ConclusionsA high monocyte count was an independent and incremental predictor of cardiovascular events in CAD patients. The monocyte count was also significantly correlated with peripheral endothelial dysfunction in CAD patients.

Evaluation of the vascular protective effects of new oral anticoagulants in high-risk patients with atrial fibrillation (PREFER-AF): study protocol for a randomized controlled trial.

BackgroundAtrial fibrillation (AF) is known to be associated with several pathophysiological mechanisms including endothelial dysfunction of the heart and arterial vessels. Recent evidence suggests that new oral anticoagulant (NOAC) treatment may improve endothelial function and the inflammatory process involved in atherosclerosis in AF patients. This study is designed to determine the efficacy of NOAC therapy in the prevention of endothelial dysfunction and the progression of atherosclerosis of AF subjects.Method/designAF patients with a CHA2DS2-VASc score >2 and no previous history of overt coronary disease, severe peripheral arterial disease (PAD) or major stroke will be registered and randomly assigned either to the NOAC group (dabigatran or rivaroxaban) or the warfarin group in this prospective, randomized, 2-year follow-up study. Reactive hyperemia peripheral arterial tonometry (RH-PAT) measurements reflecting endothelial function will be conducted using the Endo-PAT2000 device. Left and right carotid intima-media thickness (IMT) will be measured at baseline, 12 months, and 24 months. The primary endpoint is defined as change in Reactive Hyperemia Index (RHI) at 12 months. Secondary endpoints included changes in the right and left maximum IMT of the common carotid artery (CCA) and internal carotid artery (ICA), the mean IMT of the CCA and ICA at 24 months, and 24-month cardiovascular events including cardiac death, stroke, acute myocardial infarction (AMI), overall cause of death, withdrawal of drug, or bleeding events.DiscussionThis is the first study to evaluate the efficacy of NOAC therapy for the prevention of endothelial dysfunction and progression of atherosclerosis in AF subjects. These findings are expected to expand the knowledge of NOAC pleotropic action in AF patients.Trial registrationClinicalTrials.gov: NCT02544932, registered on 7 September 2015.

Assessment of vascular autonomic function using peripheral arterial tonometry.

Peripheral autonomic function is impaired in diabetic polyneuropathy. However, it is difficult to evaluate it due to the lack of non-invasive quantitative assessment. We aimed to establish a novel index to evaluate vascular autonomic function using reactive hyperemia peripheral arterial tonometry (RH-PAT), a widely performed endothelial function test. Sixty-five subjects were enrolled, including healthy subjects, cases with sympathetic nerve blockers, and diabetic patients. RH-PAT was performed with 5-min blood flow occlusion in unilateral arm. We calculated the reduction ratio of the post-occlusion pulse amplitude to the baseline in the non-occluded arm (RPN), with 1-min sliding window. In healthy subjects, RPN gradually increased with time-dependent manner. However, this phenomenon was eliminated in cases with sympathetic nerve blockers. Plasma concentration of norepinephrine was measured before and after the blood flow occlusion, which showed a significant increase. We then compared RPNs with the change in heart rate variability (HRV) parameters. RPN calculated at 5min after the reperfusion had the highest correlation with the change in sympathetic HRV parameter, and thus, we named sympathetic hypoemia index (SHI). Finally, we studied the relationship between SHI and diabetes. SHI was significantly lower in diabetic patients than matched controls. SHI, a novel index derived from RH-PAT, represented the peripheral sympathetic activity. SHI may be useful for assessing the vascular autonomic activity in diabetic patients.

Impaired Peripheral Endothelial Function Assessed by Digital Reactive Hyperemia Peripheral Arterial Tonometry and Risk of In-Stent Restenosis.

BackgroundDrug‐eluting stents are replacing bare‐metal stents, but in‐stent restenosis (ISR) remains a problem. Reactive hyperemia index (RHI) assessed by peripheral arterial tonometry evaluates endothelial function noninvasively. We prospectively assessed the prognostic value of RHI in predicting ISR after percutaneous coronary intervention.Methods and Results RHI was measured before percutaneous coronary intervention and at follow‐up (F/U) angiography (F/U RHI; 6 and 9 months post bare‐metal stents– and drug‐eluting stents– percutaneous coronary intervention, respectively) in 249 consecutive patients. At F/U, ISR (stenosis >50% of diameter) was seen in 68 patients (27.3%). F/U natural logarithm (RHI) was significantly lower in patients with ISR than in those without (0.52±0.23 versus 0.65±0.27, P<0.01); no between‐group difference in initial natural logarithm (RHI) (0.60±0.26 versus 0.62±0.25, P=0.56) was seen. By multivariate logistic regression analysis, even after adjusting for other significant parameters in univariate analysis, F/U natural logarithm (RHI) independently predicted ISR (odds ratio: 0.13; 95% CI: 0.04–0.48; P=0.002). In receiver operating‐characteristic analysis, F/U RHI was the strongest predictor of ISR (area under the curve: 0.67; 95% CI: 0.60–0.75; P<0.01; RHI <1.73 had 67.6% sensitivity, 64.1% specificity); area under the curve significantly improved from 0.62 to 0.70 when RHI was added to traditional ISR risk factors (P=0.02). Net reclassification index was significant after addition of RHI (26.5%, P=0.002).ConclusionsImpaired RHI at F/U angiography independently correlated with ISR, adding incremental prognostic value to the ISR‐risk stratification following percutaneous coronary intervention.Clinical Trial Registration URL: https://www.clinicaltrials.gov/. Unique identifier: NCT02131935.

Endothelial Dysfunction After ST-segment Elevation Myocardial Infarction and Long-term Outcome: A Study With Reactive Hyperemia Peripheral Artery Tonometry

Introduction and objectivesLong-term data on the relationship between endothelial dysfunction after ST-segment elevation myocardial infarction and future adverse clinical events are scarce. The aim of this study was to noninvasively assess whether endothelial dysfunction 4 weeks to 6 weeks after primary percutaneous coronary intervention for acute ST-segment elevation myocardial infarction predicts future clinical events. MethodsThis prospective cohort study was performed in 70 patients of the RESPONSE randomized trial, who underwent noninvasive assessment of endothelial function 4 weeks to 6 weeks after primary percutaneous coronary intervention. Endothelial function was measured by the reactive hyperemia peripheral artery tonometry method; an index<1.67 identified endothelial dysfunction. ResultsThe reactive hyperemia peripheral artery tonometry index measured on average 1.90±0.58. A total of 35 (50%) patients had endothelial dysfunction and 35 (50%) patients had normal endothelial function. Periprocedural “complications” (eg, cardiogenic shock, total atrioventricular block) were more common in patients with endothelial dysfunction than in those without (25.7% vs 2.9%; P<.01). During 4.0±1.7 years of follow-up, 20 (28.6%) patients had major adverse cardiovascular events: events occurred in 9 (25.7%) patients with endothelial dysfunction and in 11 (31.5%) patients with normal endothelial function (P=.52). There was an association between the prevalence of diabetes mellitus at baseline and the occurrence of major adverse cardiovascular events during follow-up (univariate analysis: hazard ratio=2.8; 95% confidence interval, 1.0-7.8; P<.05), and even in multivariate analyses the risk appeared to be increased, although not significantly (multivariate analysis: hazard ratio=2.5; 95% confidence interval, 0.8-7.5). ConclusionsIn this series of patients who survived an ST-segment elevation myocardial infarction, endothelial dysfunction, as assessed by reactive hyperemia peripheral artery tonometry 4 weeks to 6 weeks after myocardial infarction, did not predict future clinical events during a mean follow-up of 4 years.

Disfunción endotelial tras infarto de miocardio con elevación del segmento ST y evolución a largo plazo: un estudio con tonometría arterial periférica e hiperemia reactiva

Introduction and objectivesLong-term data on the relationship between endothelial dysfunction after ST-segment elevation myocardial infarction and future adverse clinical events are scarce. The aim of this study was to noninvasively assess whether endothelial dysfunction 4 to 6 weeks after primary percutaneous coronary intervention for acute ST-segment elevation myocardial infarction predicts future clinical events. MethodsThis prospective cohort study was performed in 70 patients of the RESPONSE randomized trial, who underwent noninvasive assessment of endothelial function 4 to 6 weeks after primary percutaneous coronary intervention. Endothelial function was measured by the reactive hyperemia peripheral artery tonometry method; an index<1.67 identified endothelial dysfunction. ResultsThe reactive hyperemia peripheral artery tonometry index measured on average 1.90±0.58. A total of 35 (50%) patients had endothelial dysfunction and 35 (50%) patients had normal endothelial function. Periprocedural “complications” (eg, cardiogenic shock, total atrioventricular block) were more common in patients with endothelial dysfunction than in those without (25.7% vs 2.9%; P<.01). During 4.0±1.7 years of follow-up, 20 (28.6%) patients had major adverse cardiovascular events: events occurred in 9 (25.7%) patients with endothelial dysfunction and in 11 (31.5%) patients with normal endothelial function (P=.52). There was an association between the prevalence of diabetes mellitus at baseline and the occurrence of major adverse cardiovascular events during follow-up (univariate analysis: hazard ratio=2.8; 95% confidence interval, 1.0-7.8; P<.05), and even in multivariate analyses the risk appeared to be increased, although not significantly (multivariate analysis: hazard ratio=2.5; 95% confidence interval, 0.8-7.5). ConclusionsIn this series of patients who survived an ST-segment elevation myocardial infarction, endothelial dysfunction, as assessed by reactive hyperemia peripheral artery tonometry 4 to 6 weeks after myocardial infarction, did not predict future clinical events during a mean follow-up of 4 years.Full English text available from:www.revespcardiol.org/en

Endothelial function assessment in nutritional research studies: a comparison of two arterial occlusion sites for assessing reactive hyperemia using a peripheral arterial tonometry device

Endothelial function assessment can be an important tool in evaluating artery health in humans, and can be an important phenotyping tool in nutritional research studies as well as an early indicator of cardiovascular disease. We conducted a study of endothelial function in healthy adults using reactive hyperemia peripheral arterial tonometry (RH‐PAT) by the EndoPAT™ device (Itamar Medical Ltd., Caesarea, Israel) in order to compare two arterial occlusion sites. Brachial artery (upper arm) occlusion is the most common occlusion site, yet a forearm occlusion site may be a potentially valid site for endothelial function testing. RH‐PAT testing is an operator independent, non‐invasive technique that measures the arterial pulse wave amplitude using pneumatic fingertip probes during reactive hyperemia allowing a RH‐PAT index (RHI) to be calculated. Reactive hyperemia was achieved by occluding either the upper arm (brachial artery) or the forearm (ulnar and radial arteries) in the individual using a blood pressure cuff inflated to ~200 mmHg for 5 minutes. Twenty healthy adults (14 female, 6 male), age 38 ± 12 years (mean ± SD) and BMI 24 ± 3 kg/m2 participated in the study. RH‐PAT measurements were determined in the morning after a 12 hour fast. Participants were tested approximately 3 days apart using a crossover design with randomization of upper arm and forearm as occlusion sites. The participant's non‐dominant arm was always the occluded arm. Participants were tested in a quiet, temperature‐controlled (21–24°C) room in a supine position for at least 15 minutes prior to the 15 minute test: 5 minute baseline, 5 minute occlusion, and 5 minute post‐occlusion. A self‐reported numeric pain intensity scale (0–10) was used to evaluate pain during the occlusion and post‐occlusion (hyperemic period) portion of the measurement. The RHI is the post‐to‐pre occlusion PAT signal ratio in the occluded arm, relative to the same ratio in the control arm, corrected for baseline vascular tone of the occluded arm. The mean RHI for the two occlusion sites: 2.15 ± 0.78 (upper arm) and 2.36 ± 0.75 (forearm) was not different (p=0.18, paired t‐test). A Pearson correlation of the RHI from both sites (r=0.602, p=0.005) was positive and significant. The mean reported pain intensity for the upper arm was 3.7 ± 1.3 compared to 2.7 ± 1.8 for the forearm; these indices were significantly different (p=0.002, signed‐rank test). In summary, occlusion of the forearm appears to be a potentially valid alternate occlusion site for RH‐PAT measurement and is less painful than using the upper arm as an occlusion site. In addition, the occlusion site should be standardized in the study protocol. Human study approved by the UC Davis Institutional Review Board.Support or Funding InformationUSDA, ARS Projects: 2032‐51000‐022; 203253000‐001

Cardiovascular efficacy of sitagliptin in patients with diabetes at high risk of cardiovascular disease: a 12-month follow-up

BackgroundGliptins should have beneficial effects beyond glycemic control, potentially on the pathophysiology of cardiovascular (CV) diseases, with some basic studies demonstrating this possibility. However, we are yet to answer whether there are any direct CV effects in the clinical setting. We aimed to examine the beneficial effects of sitagliptin in Japanese patients with diabetes and high CV risk for 12 months.MethodsThis was a prospective, multicenter, observational study of 205 patients with type 2 diabetes. All participants had more than one major CV risk factor and were treated with sitagliptin for 12 months. At 3 or 12 months, we examined the effects of treatment on glycemic control, CV function (by electrocardiography, echocardiography, and reactive hyperemia-peripheral arterial tonometry), and CV biomarkers.ResultsPatients were predominantly elderly (68.8 ± 9.9 years) and male (71.5 %) and typically had more than three CV risk factors (79.2 %). Treatment with sitagliptin significantly reduced the hemoglobin A1c (HbA1c) level from 7.09 % ± 0.81 % at baseline to 6.67 % ± 0.69 % at 3 months and 6.68 % ± 0.73 % at 12 months (both P < 0.001). The reduction in HbA1c was also in tandem with the decrease in the level of high-sensitive C-reactive protein throughout the study. Independent of the change in HbA1c, sitagliptin reduced systolic (−7.0 ± 18.9 mmHg) and diastolic blood pressure (−5.1 ± 11.7 mmHg) at 12 months, and this was associated with a decrease in urinary albumin. In contrast, there were no beneficial effects on cardiac and endothelial function or on the levels of serum B-type natriuretic peptide, high-sensitive troponin T, and urinary 8-hydroxy-2′-deoxyguanosine.ConclusionsIn Japanese patients with diabetes and multiple CV risk factors, sitagliptin showed a decrease in blood pressure associated with an improvement in albuminuria in addition to glycemic control.Trial registration: UMIN000005663Electronic supplementary materialThe online version of this article (doi:10.1186/s12933-016-0371-z) contains supplementary material, which is available to authorized users.

Helicobacter pylori-seropositivity along with pro-inflammatory interleukin-1 polymorphisms correlated with myocardial infarction

BackgroundHost genetic factors of interleukin (IL)-1 polymorphisms influence Helicobacter pylori infection pathogenic activity. We examined whether H. pylori-infected patients with IL-1 polymorphisms are associated with myocardial infarction (MI). Materials and methodsWe recruited 594 consecutive coronary artery disease patients and excluded those who met exclusion criteria. After matching age and sex, 82 cases with MI and 82 controls were enrolled. Immunoglobulin G antibodies against H. pylori and IL-1 polymorphisms (IL-1 beta-511 base pairs and IL-1 receptor antagonist) were analyzed. We assessed high sensitivity C-reactive protein (hs-CRP) level and reactive hyperemia-peripheral arterial tonometry (RH-PAT) index (RHI) using the EndoPAT2000 system. ResultsThe simultaneous prevalence of H. pylori-seropositivity and IL-1 polymorphisms was 45.1% and 19.5% in the cases and controls, respectively (P=0.001). H. pylori-positive patients with IL-1 polymorphisms showed significantly higher serum levels of natural logarithm of hs-CRP in the cases and controls (−2.8±1.0 vs. −3.4±0.6, respectively; P=0.003 and −2.8±0.9 vs. −3.2±0.6, respectively; P=0.02) and significantly lower levels of natural logarithm of RHI in the cases and controls (0.51±0.13 vs. 0.61±0.23, respectively; P=0.039 and 0.47±0.13 vs. 0.69±0.23, respectively; P=0.005). H. pylori-seropositivity with IL-1 polymorphisms was significantly associated with MI by logistic regression analysis (odds ratio, 4.83; 95% confidence interval, 1.99–11.7; P<0.001). ConclusionsH. pylori-positive patients with IL-1 polymorphisms showed higher levels of hs-CRP and lower levels of RHI, and were significantly correlated with the MI.

Clinical Significance of Peripheral Endothelial Function for Left Atrial Blood Stagnation in Nonvalvular Atrial Fibrillation Patients With Low-to-Intermediate Stroke Risk

In patients who have atrial fibrillation (AF) with CHADS2score of 0-1 (categorized as low-to-intermediate risk), there is little information on stratifying the risk of stroke. This study aimed to determine whether impaired endothelial function assessed by reactive hyperemia-peripheral arterial tonometry (RH-PAT) predicted left atrial blood stagnation in these patients. We enrolled 81 consecutive patients with nonvalvular AF. The reactive hyperemia index (RHI) was measured using RH-PAT. Transesophageal echocardiography was performed to determine spontaneous echo contrast (SEC) before direct-current cardioversion or radiofrequency catheter ablation. SEC was found in 49 patients (60%). The RHI was significantly lower in patients with than without SEC. Multivariate analysis demonstrated that RHI was one of the independent determinants of SEC (OR per 0.1, 1.26; 95% CI, 1.11-1.49; P=0.002) in all patients. In addition, RHI was a significant determinant of SEC (AUC, 0.73; 95% CI, 0.63-0.89; P=0.0017) in patients with low-to-intermediate risk. At an RHI cut-off <1.62, the sensitivity and specificity for the identification of patients with SEC were 58% and 89%, respectively. Impaired endothelial function assessed by RH-PAT might help to predict the presence of SEC in patients with low-to-intermediate risk of stroke. (Circ J 2016; 80: 2117-2123).