Endothelial-protective effects of a G-protein-biased sphingosine-1 phosphate receptor-1 agonist, SAR247799, in type-2 diabetes rats and a randomized placebo-controlled patient trial.

AIMS: SAR247799 is a G-protein-biased sphingosine-1 phosphate receptor-1 (S1P1 ) agonist designed to activate endothelial S1P1 and provide endothelial-protective properties, while limiting S1P1 desensitization and consequent lymphocyte-count reduction associated with higher doses. The aim was to show whether S1P1 activation can promote endothelial effects in patients and, if so, select SAR247799 doses for further clinical investigation. METHODS: Type-2 diabetes patients, enriched for endothelial dysfunction (flow-mediated dilation, FMD <7%; n = 54), were randomized, in 2 sequential cohorts, to 28-day once-daily treatment with SAR247799 (1 or 5 mg in ascending cohorts), placebo or 50 mg sildenafil (positive control) in a 5:2:2 ratio per cohort. Endothelial function was assessed by brachial artery FMD. Renal function, biomarkers and lymphocytes were measured following 5-week SAR247799 treatment (3 doses) to Zucker diabetic fatty rats and the data used to select the doses for human testing. RESULTS: The maximum FMD change from baseline vs placebo for all treatments was reached on day 35; mean differences vs placebo were 0.60% (95% confidence interval [CI] -0.34 to 1.53%; P = .203) for 1 mg SAR247799, 1.07% (95% CI 0.13 to 2.01%; P = .026) for 5 mg SAR247799 and 0.88% (95% CI -0.15 to 1.91%; P = .093) for 50 mg sildenafil. Both doses of SAR247799 were well tolerated, did not affect blood pressure, and were associated with minimal-to-no lymphocyte reduction and small-to-moderate heart rate decrease. CONCLUSION: These data provide the first human evidence suggesting endothelial-protective properties of S1P1 activation, with SAR247799 being as effective as the clinical benchmark, sildenafil. Further clinical testing of SAR247799, at sub-lymphocyte-reducing doses (≤5 mg), is warranted in vascular diseases associated with endothelial dysfunction.

Impact of high on-treatment platelet reactivity after angioplasty in patients with peripheral arterial disease.

Objective: High on-treatment platelet reactivity (HTPR) to dual antiplatelet therapy (DAPT) predicts adverse events in coronary artery disease patients. In peripheral artery disease (PAD) patients, data concerning the clinical impact of HTPR are limited. Therefore, we evaluated the incidence of (i) HTPR to DAPT and (ii) its impact on 6 months outcome after angioplasty.Methods and results: In this prospective single center analysis, we investigated 102 consecutive patients with PAD from 2016 to 2017. All patients underwent peripheral endovascular treatment due to intermittent claudication (Fontaine IIb). Clopidogrel effects were measured using vasodilator-stimulated protein phosphorylation (VASP) assay, aspirin effects by light-transmission aggregometry (LTA). Major adverse limb events (MALE), major adverse cardiac and cerebrovascular events (MACCE) and BARC bleeding (bleeding academic research consortium classification) within 6 months were assessed. HTPR to clopidogrel (n = 37, 36%), to aspirin (n = 11, 11%) and to both (n = 11, 11%) were frequent. Compared to sufficient platelet inhibition by aspirin and clopidogrel (n = 43, 42%), patients with dual HTPR showed a higher risk of MALE at 6 months (27% vs. 7%; hazard ratio [HR]: 4.45; 95% confidence interval [CI]: 1.1 to 67.8; p = .03). This was independent of diabetes, creatinine, body mass index, and age as well as of procedural details in a multivariate logistic regression analysis. MACCE (n = 2) and BARC bleeding rates (n = 2) were low.Conclusion: In this small exploratory study, HTPR was frequent in PAD patients. Furthermore, the results are suggestive that MALE might be associated with dual HTPR. This leads to the hypothesis that optimized antithrombotic regimens post percutaneous transluminal angioplasty should be tested in clinical trials.

Stent fractures after common femoral artery bail-out stenting due to suture device failure in TAVR.

BACKGROUND: Vascular access site-related complications are frequent in the context of transfemoral transcatheter aortic valve replacement (TAVR). The implantation of a covered stent graft is an effective treatment option for bleeding control. However, the external iliac and common femoral arteries are exposed to flexion of the hip joint. Therefore, stent compression and stent/strut fractures may occur, facilitating stent occlusion. PATIENTS AND METHODS: In all 389 patients who received transfemoral TAVR from 2013-2015 at the Düsseldorf Heart Centre, we monitored the management of vascular access site-related complications. Our analyses focused on immediate technical success and bleeding control, primary patency, and the occurrence of stent/strut fractures after six to 12 months of follow-up. RESULTS: Vascular access site-related complications occurred in 13 % (n = 51), whereof in 10 patients, the bleeding was successfully managed by prolonged compression. In 40 out of 51 patients, a covered stent graft was implanted in the common femoral artery, leading to 100 % immediate bleeding control. After a mean follow-up of 334 ± 188 days, 28 stents out of 29 patients with completed follow-up (excluding e. g. death) were without flow-limiting stenosis (primary patency 97 %) or relevant stent compression (diameter pre/post 8.6/8.1 mm, p = 0.048, late lumen loss 1.1 ± 0.2 mm, mean flow velocity 92 ± 34 cm/s). In four asymptomatic patients, stent/strut fractures were detected (14 %) without flow-limiting stenosis. CONCLUSIONS: The implantation of a covered stent graft is highly effective and safe to control vascular access site-related complications after TAVR. Stent/strut fractures in the flexible segment of the common femoral artery may occur, as consequently verified by X-ray visualization, but show no impairment on flow or clinical parameters after six to 12 months.

Impact of Continuous Positive Airway Pressure on Left Ventricular Systolic Loading and Coronary Flow Reserve in Healthy Young Men.

BACKGROUND: Increased augmentation index (AIx) is accompanied by an elevated cardiovascular risk. A reduction of AIx is known for long-term continuous positive airway pressure (CPAP) therapy. We hypothesised that acute preload and left ventricular workload effects AIx and subendocardial viability ratio (SEVR) as a marker of coronary flow reserve. METHODS: Increased augmentation index and central blood pressure parameters were measured by radial artery tonometry in 17 healthy men (32/±6years) at rest and during CPAP ventilation at pressures of 5, 10mbar and after recovery. In a subset of seven individuals, haemodynamic parameters and autonomic function were additionally examined using combined impedance cardiography and continuous noninvasive blood pressure monitoring. RESULTS: Continuous positive airway pressure reduced heart rate corrected (AIx@75) (-2.8±8.1 [rest] to -10.7±11.3 [5mbar], p<0.01, to -12.2±10.5% [10mbar], p<0.01) and systolic time integral as a marker of left ventricular workload (2115±231 [rest] to 1978±290 [5mbar], p=0.02 to 1940±218 [10mbar], p<0.01 to 2013±241mmHg/s per min [recovery], p=0.03), while central systolic pressure did not change during CPAP. Total Peripheral Resistance Index increased reaching level of significance at 10mbar CPAP condition (1701±300 [rest] to 1850±301dyn*s*m2/cm5 [10mbar], p=0.04). There was a reversible increase of SEVR under CPAP conditions. CONCLUSIONS: Continuous positive airway pressure ventilation acutely reduces AIx, heart rate and left ventricular workload in healthy young men. These effects seem to be mediated by left ventricular filling pressure, workload and reflection wave. Furthermore, we found an increase of subendocardial viability ratio as an indication for a rising coronary flow reserve by CPAP.

Measurement of endothelium-dependent vasodilation in mice--brief report.

OBJECTIVE: Endothelium-dependent, flow-mediated vasodilation after an increase in shear stress at the endothelial lining of conduit arteries during reactive hyperemia after ischemia is a fundamental principle of vascular physiology adapting blood flow to demand of supplied tissue. Flow-mediated vasodilation measurements have been performed in human studies and are of diagnostic and prognostic importance, but have been impossible because of technical limitations in transgenic mice to date, although these represent the most frequently used animal model in cardiovascular research. APPROACH AND RESULTS: Using high-frequency ultrasound, we visualized, quantified, and characterized for the first time endothelium-dependent dilation of the femoral artery after temporal ischemia of the lower part of the hindlimb and demonstrated that the signaling was almost exclusively dependent on stimulation of endothelial nitric oxide synthase, similar to acetylcholine, completely abolished after pharmacological or genetic inhibition of endothelial nitric oxide synthase and endothelial denudation, substantially impaired in mice of increasing age and cholesterol-fed ApoE knock outs and increased by the dietary polyphenol (-)-epicatechin. Intra- and interindividual variability were similar to the human methodology. CONCLUSIONS: The physiology of flow-mediated vasodilation in mice resembles that in humans underscoring the significance of this novel technology to noninvasively, serially, and reliably quantify flow-mediated vasodilation in transgenic mice.

Cocoa flavanol intake improves endothelial function and Framingham Risk Score in healthy men and women: a randomised, controlled, double-masked trial: the Flaviola Health Study.

Cocoa flavanol (CF) intake improves endothelial function in patients with cardiovascular risk factors and disease. We investigated the effects of CF on surrogate markers of cardiovascular health in low risk, healthy, middle-aged individuals without history, signs or symptoms of CVD. In a 1-month, open-label, one-armed pilot study, bi-daily ingestion of 450 mg of CF led to a time-dependent increase in endothelial function (measured as flow-mediated vasodilation (FMD)) that plateaued after 2 weeks. Subsequently, in a randomised, controlled, double-masked, parallel-group dietary intervention trial (Clinicaltrials.gov: NCT01799005), 100 healthy, middle-aged (35-60 years) men and women consumed either the CF-containing drink (450 mg) or a nutrient-matched CF-free control bi-daily for 1 month. The primary end point was FMD. Secondary end points included plasma lipids and blood pressure, thus enabling the calculation of Framingham Risk Scores and pulse wave velocity. At 1 month, CF increased FMD over control by 1·2 % (95 % CI 1·0, 1·4 %). CF decreased systolic and diastolic blood pressure by 4·4 mmHg (95 % CI 7·9, 0·9 mmHg) and 3·9 mmHg (95 % CI 6·7, 0·9 mmHg), pulse wave velocity by 0·4 m/s (95 % CI 0·8, 0·04 m/s), total cholesterol by 0·20 mmol/l (95 % CI 0·39, 0·01 mmol/l) and LDL-cholesterol by 0·17 mmol/l (95 % CI 0·32, 0·02 mmol/l), whereas HDL-cholesterol increased by 0·10 mmol/l (95 % CI 0·04, 0·17 mmol/l). By applying the Framingham Risk Score, CF predicted a significant lowering of 10-year risk for CHD, myocardial infarction, CVD, death from CHD and CVD. In healthy individuals, regular CF intake improved accredited cardiovascular surrogates of cardiovascular risk, demonstrating that dietary flavanols have the potential to maintain cardiovascular health even in low-risk subjects.

Human red blood cells at work: identification and visualization of erythrocytic eNOS activity in health and disease.

A nitric oxide synthase (NOS)-like activity has been demonstrated in human red blood cells (RBCs), but doubts about its functional significance, isoform identity and disease relevance remain. Using flow cytometry in combination with the nitric oxide (NO)-imaging probe DAF-FM we find that all blood cells form NO intracellularly, with a rank order of monocytes > neutrophils > lymphocytes > RBCs > platelets. The observation of a NO-related fluorescence within RBCs was unexpected given the abundance of the NO-scavenger oxyhemoglobin. Constitutive normoxic NO formation was abolished by NOS inhibition and intracellular NO scavenging, confirmed by laser-scanning microscopy and unequivocally validated by detection of the DAF-FM reaction product with NO using HPLC and LC-MS/MS. Using immunoprecipitation, ESI-MS/MS-based peptide sequencing and enzymatic assay we further demonstrate that human RBCs contain an endothelial NOS (eNOS) that converts L-(3)H-arginine to L-(3)H-citrulline in a Ca(2+)/calmodulin-dependent fashion. Moreover, in patients with coronary artery disease, red cell eNOS expression and activity are both lower than in age-matched healthy individuals and correlate with the degree of endothelial dysfunction. Thus, human RBCs constitutively produce NO under normoxic conditions via an active eNOS isoform, the activity of which is compromised in patients with coronary artery disease.

Dietary flavanol intervention lowers the levels of endothelial microparticles in coronary artery disease patients.

Current evidence suggests that regenerative v. degenerative endothelial responses can be integrated in a clinical endothelial phenotype, reflecting the net result between damage from risk factors and endogenous repair capacity. We have previously shown that a cocoa flavanol (CF) intervention can improve endothelial function and increase the regenerative capacity of the endothelium by mobilising circulating angiogenic cells in patients with coronary artery disease (CAD). The aim of the present study was to investigate whether CF can lower the levels of circulating endothelial microparticles (EMP), markers of endothelial integrity, along with improvements in endothelial function. The levels of EMP in the frozen plasma samples of CAD patients were measured along with endothelial function (flow-mediated vasodilation, FMD); n 16, FMD data published previously), and these data were compared with those of young (n 12) and age-matched (n 12) healthy control subjects. The CAD patients exhibited significantly increased levels of EMP along with impaired FMD when compared with the healthy control subjects. The levels of CD144⁺ and CD31⁺/41⁻ EMP were inversely correlated with FMD (r -0.67, P=0.01 and r -0.59, P=0.01, respectively). In these CAD patients, the levels of EMP were measured after they had consumed a drink containing 375 mg of CF (high-CF intervention, HiFI) or 9 mg of CF (macro- and micronutrient-matched low-CF control, LoFl) twice daily over a 30-d period in a randomised, double-blind, cross-over study. After 1 month of HiFI, the levels of CD31⁺/41⁻ and CD144⁺ EMP decreased (-25 and -23%, respectively), but not after LoFl. Our data show that flavanols lower the levels of EMP along with higher endothelial function, lending evidence to the novel concept that flavanols may improve endothelial integrity.

Temporary decrease in microvascular tissue saturation after transcatheter aortic valve implantation.

BACKGROUND: Data on the effect of transcatheter aortic valve implantation (TAVI) on peripheral microcirculation are limited. OBJECTIVE: The aim of this study is to evaluate peripheral microvascular tissue saturation (StO2) before and after TAVI in relation to central and peripheral hemodynamics, cardiac and renal function. METHODS: In this single-center prospective study, patients with severe aortic stenosis (sAS) scheduled for TAVI or cardiac catheterization (control) were assessed before and up to five days after the procedure. Cardiac function including cardiac output (CO) was assessed by echocardiography. Brachial (bBP) and central blood pressure (cBP), ankle brachial index (ABI), and parameters of arterial stiffness, including augmentation pressure (AP) and augmentation index adjusted for heart rate (AIx@HR75) were measured to assess hemodynamic changes. StO2 was measured in all extremities using a near-infrared spectroscopy (NIRS) camera. Renal function was measured by creatinine levels. RESULTS: 26 patients underwent TAVI and 11 patients served as control. Cardiac output was significantly increased, whereas hemodynamic parameters and peripheral StO2 were significantly decreased after TAVI. At follow-up, StO2 returned to baseline values. Changes in StO2 were negatively related to creatinine levels. CONCLUSION: Transcatheter aortic valve implantation causes a temporary decrease in microvascular tissue saturation that is associated with renal function.

Impact of Peripheral Angioplasty on Wound Oxygenation and Healing in Patients with Chronic Limb-Threatening Ischemia Measured by Near-Infrared Spectroscopy.

Managing chronic limb-threatening ischemia (CLTI) is challenging due to difficulties in assessing tissue oxygen saturation in ulcers. Near-infrared spectroscopy (NIRS) is a non-invasive method for measuring tissue oxygen saturation (StO2). This study evaluated the effects of endovascular treatment (EVT) on StO2 and wound healing in CLTI patients, comparing NIRS to standard ankle-brachial index (ABI) measurements. Using the Duesseldorf PTA Registry, 43 CLTI patients were analyzed: 27 underwent EVT, and 16 received conservative treatment. ABI assessed macrocirculation, while NIRS measured wound, wound area, and mean foot StO2 at baseline, post-EVT, and four-month follow-up. Wound severity was classified by wound area and wound, ischemia, and foot infection (WIfI) score. Wound StO2 increased significantly (median (interquartile range (IQR)), 38 (49.3) to 60 (34.5)%, p = 0.004), as did wound area StO2 (median (IQR), 70.9 (21.6) to 72.8 (18.3)%, p < 0.001), with no significant changes in the control group by four-month follow-up. Wound area decreased significantly after EVT (mean ± SD, 343.1 ± 267.8 to 178.1 ± 268.5 mm2, p = 0.01) but not in the control group. Changes in wound StO2, wound area StO2, and WIfI score correlated with wound area reduction, unlike ABI. This small exploratory study shows that NIRS-measured StO2 improvements after EVT correlate with reduced wound area and WIfI scores, highlighting NIRS as a potential enhancement for CLTI wound management in addition to ABI.

Endovascular Treatment of Flow-Limiting Iliofemoral Stenosis Improves Left Ventricular Diastolic Function in Patients With HFpEF by Reducing Aortic Pulsatile Load.

BACKGROUND: Recent research indicates that there is a high prevalence of heart failure with preserved ejection fraction in patients with peripheral artery disease. We hypothesized that endovascular treatment (EVT) of flow-limiting peripheral stenosis improves left ventricular (LV) diastolic function. METHODS: Thirty patients with symptomatic peripheral artery disease and heart failure with preserved ejection fraction according to Heart Failure Association-preserved ejection fraction score who were scheduled for EVT or angiography were investigated at baseline, the day after EVT (n=25) or angiography (control, n=5), and at 4 months follow-up. Peripheral hemodynamics were determined by the total peripheral resistance, common femoral artery flow, and ankle brachial index. Aortic function was measured by arterial compliance, augmentation index, and pulse wave velocity. Aortic pulsatile load was estimated as the characteristic impedance of the proximal aorta and the magnitude of wave reflection (reflection coefficient). LV mass index, LV mean wall thickness, and systolic and diastolic function were assessed using echocardiography. Patient-centered outcomes were treadmill walking distance and New York Heart Association class. RESULTS: After EVT, peripheral hemodynamics changed significantly with a decrease in total peripheral resistance and an increase in common femoral artery flow and ankle brachial index. Aortic function improved after EVT, with significantly reduced augmentation index and pulse wave velocity and increased compliance immediately and at follow-up, resulting in a reduction in aortic pulsatile load (characteristic impedance of the proximal aorta and reflection coefficient). Concurrently, LV diastolic function improved after EVT compared with control, acutely and at follow-up, with increased septal and lateral e´ velocities and decreased E/e´ and left atrial volume index. The LV mass index and LV mean wall thickness decreased at follow-up. The New York Heart Association class and treadmill walking distance improved post-EVT at follow-up. Augmentation index, pulse wave velocity, and arterial compliance were identified as independent contributors to E/e´. CONCLUSIONS: Endovascular treatment of flow-limiting iliofemoral stenosis reduces aortic pulsatile load and concurrently lowers total peripheral resistance. This beneficial effect is associated with an acute and sustained improvement of left ventricular diastolic function. REGISTRATION: URL: http://www.clinicaltrials.gov; Unique identifier: NCT02728479.

Cocoa flavanol supplementation preserves early and late radial artery function after transradial catheterization.

Background: The transradial approach for coronary angiography is associated with fewer complications and preferred over the femoral approach. Injury to the radial artery (RA) endothelium elicits intimal hyperplasia, possibly resulting in total occlusion and limb functional decline. Flavanols are known to improve endothelial function. Effects on arterial remodeling after mechanical injury are unknown. Objective: To investigate the effects of cocoa flavanols on (a) intimal hyperplasia and (b) endothelial functional recovery after mechanical vascular wall injury through transradial coronary angiography (TCA). Methods: Primary endpoint in this double-blind, randomized, controlled trial was RA intima-media thickness (IMT) after 6 months follow-up (FU). Secondary endpoints were RA flow-mediated vasodilation (FMD) and fractional diameter change (Fdc). Further luminal diameter and circulating endothelial microparticles (EMP) were assessed. Thirty-six male patients undergoing elective TCA were included. Flavanol or matched placebo supplementation started 7 days prior TCA (cocoa flavanol 1000 mg day-1) for 14 days. Four measurements spanned three periods over 6-moths-FU. Results: TCA induced sustained intimal hyperplasia in the placebo-, but not in the flavanol-group (IMT 0.44 ± 0.01 vs. 0.37 ± 0.01 mm, p = 0.01). FMD decreased after TCA in both groups, but recovered to baseline after 6 months in the flavanol group only. Fdc acutely decreased, EMPs increased in the placebo-, not in the flavanol -group. Luminal diameter remained unchanged in both groups. Conclusion: Peri-interventional cocoa flavanol supplementation prevents long-term intima media thickening and endothelial dysfunction 6 months after TCA opening the perspective for dietary interventions to mitigate endothelial cell damage and intimal hyperplasia after mechanical injury.

Cocoa flavanols improve peakVO2 and exercise capacity in a randomized double blinded clinical trial in healthy elderly people.

Background: Loss of functional capacity is one of the hallmarks in cardiovascular aging. Cocoa flavanols (CF) exert favorable effects on endothelial function, blood pressure, and inflammation. These cardiovascular health markers worsen with increasing age and limit functional exercise capacity. Aim: To investigate the effect of CF on cardiorespiratory-fitness in healthy elderly people. Methods: In a randomized, double-masked, placebo-controlled, parallel-group dietary intervention trial, 68 healthy elderly people (55-79 years, 28 female) received either 500 mg of CF or a nutrient-matched control capsule twice a day for 30 days. Primary endpoint was defined as peak oxygen consumption (VO2) in a cardiopulmonary exercise test (CPET). Secondary endpoints were oxygen pulse (VO2 per heart rate (HR)), resting blood pressure (BP), and resting vascular function. Results: After 30 days of CF intake peakVO2 increased by 190 ml min-1 (95% CI 1-371 ml min-1) and peakVO2 per kg by 2.5 ml (min kg)-1 (95% CI 0.30-4.2 ml (min kg)-1). O2-pulse increased by 1.7 ml (95% CI 0.29-3.2 ml) and max exercise capacity by 9.6 W (95% CI 2.1-17.7 W). CF decreased resting systolic and diastolic BP by 5.4 mmHg (95% CI -10.7 to -0.1 mmHg) and 2.9 mmHg (95% CI -5.5 to -0.4 mmHg), respectively. Flow-mediated vasodilation (FMD) increased by an absolute 1.3% (95% CI 0.76-1.79%) in the CF group. Indexes of pulmonary function were not affected. No changes for primary and secondary endpoints were detected in control. Conclusion: CF substantially improve markers of cardiorespiratory fitness in healthy elderly humans highlighting their potential to preserve cardiovascular health with increasing age.

Flavanol Consumption in Healthy Men Preserves Integrity of Immunological-Endothelial Barrier Cell Functions: Nutri(epi)genomic Analysis.

SCOPE: While cocoa flavanol (CF) consumption improves cardiovascular risk biomarkers, molecular mechanisms underlying their protective effects are not understood. OBJECTIVE: To investigate nutri(epi)genomic effects of CF and identify regulatory networks potential mediating vascular health benefits. METHODS AND RESULTS: Twenty healthy middle-aged men consume CF (bi-daily 450 mg) or control drinks for 1 month. Microarray analysis identifies 2235 differentially expressed genes (DEG) involved in processes regulating immune response, cell adhesion, or cytoskeleton organization. Distinct patterns of DEG correlate with CF-related changes in endothelial function, arterial stiffness, and blood pressure. DEG profile negatively correlates with expression profiles of cardiovascular disease patients. CF modulated DNA methylation profile of genes implicates in cell adhesion, actin cytoskeleton organization, or cell signaling. In silico docking analyses indicate that CF metabolites have the potential of binding to cell signaling proteins and transcription factors. Incubation of plasma obtained after CF consumption decrease monocyte to endothelial adhesion and dose-dependently increase nitric oxide-dependent chemotaxis of circulating angiogenic cells further validating the biological functions of CF metabolites. CONCLUSION: In healthy humans, CF consumption may mediate vascular protective effects by modulating gene expression and DNA methylation towards a cardiovascular protective effect, in agreement with clinical results, by preserving integrity of immunological-endothelial barrier functions.

Angioplasty of Flow-Limiting Stenosis Reduces Aortic and Brachial Blood Pressure in Patients With Peripheral Artery Disease.

Background Arterial hypertension affects cardiovascular outcome in patients with peripheral artery disease (PAD). We hypothesized that angioplasty of peripheral arterial stenoses decreases aortic (aBP) and brachial blood pressure (bBP). Methods and Results In an index cohort (n=30), we simultaneously measured aBP, bBP, augmentation index (AIx), and aortic pulse wave velocity (PWV) before and after angioplasty of the iliac and femoropopliteal arteries; diagnostic angiography served as a control. In an all-comer registry cohort (n=381), we prospectively measured bBP in patients scheduled for angioplasty of the iliac, femoral, and crural arteries or diagnostic angiography. Systolic aBP decreased after iliac (Δ-25 mmHg; 95% CI, -30 to -20; P<0.0001) and femoropopliteal angioplasty (Δ-12 mmHg; 95% CI, -17 to -5; P<0.0001) as compared with diagnostic angiography. Diastolic aBP decreased after iliac (Δ-9 mmHg; 95% CI, -13 to -1; P=0.01) but not femoropopliteal angioplasty. In parallel, AIx significantly dropped, whereas PWV remained stable. In the registry cohort, systolic bBP decreased after angioplasty of the iliac (Δ-17 mmHg; 95% CI, -31 to -8; P=0.0005) and femoropopliteal arteries (Δ-10 mmHg; 95% CI, -23 to -1; P=0.04) but not the crural arteries, as compared with diagnostic angiography. Diastolic bBP decreased after iliac (Δ-10 mmHg; 95% CI, -17 to -2; P=0.01) and femoropopliteal angioplasty (Δ-9 mmHg; 95% CI, -15 to -1; P=0.04). Multivariate analysis identified baseline systolic bBP and site of lesion as determinants of systolic bBP drop after endovascular treatment. Conclusions Angioplasty of flow-limiting stenoses in patients with peripheral artery disease lowers aortic and brachial blood pressure with more pronounced effects at more proximal lesion sites and elevated baseline systolic blood pressure. These data indicate a role of endovascular treatment to acutely optimize blood pressure in patients with peripheral artery disease. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT02728479.

Improving the Assessment of Flow-Mediated Dilation Through Detection of Peak Time in Healthy Subjects and Subjects With Type 2 Diabetes.

The assessment of flow-mediated dilation (FMD) is widely used to quantify endothelial function. Historically, FMD was determined at 60 seconds post-cuff deflation. We investigated whether FMD would be more accurate if determined at maximum dilatory peak (MDP) than at 60 seconds in healthy subjects and subjects with type 2 diabetes mellitus (T2DM). We studied 95 healthy and 72 subjects with T2DM and assessed FMD at MDP, 60 and 90 seconds. Twenty-four healthy and 12 subjects with T2DM underwent a repeat FMD after 28 days. In healthy subjects, FMD at MDP was higher than at 60 and 90 seconds, with mean difference MDP versus 60 seconds 1.14% (95% CI: 0.6-1.7); P < .0001 and MDP versus 90 seconds 1.9% (95% CI: 1.3-2.5) with similar results in T2DM, that is, 1.0% (95% CI: 0.1-1.9) and 2.3% (95% CI: 1.3-3.2), respectively. Intraindividual variability was lowest with MDP compared with 60 and 90 seconds, that is, 15.0 versus 23.2% and 40.0%, respectively, resulting in a more than 2-fold reduction in necessary sample size. In healthy subjects and subjects with T2DM, assessment of FMD using MDP results in a more accurate and precise assessment leading to a substantial reduction in sample size.

Impact of high on-treatment platelet reactivity after angioplasty in patients with critical limb ischemia.

OBJECTIVES: Dual antiplatelet therapy (DAPT) with aspirin and clopidogrel is standard of care in patients with peripheral artery disease (PAD) after percutaneous transluminal angioplasty (PTA). However, high on treatment platelet reactivity (HTPR) to DAPT is frequent and associated with major adverse limb events (MALE) in PAD patients. Nevertheless, association of MALE and HTPR in patients with critical limb ischemia (CLI) is not known. Moreover, comorbidities might confound response to antiplatelet medication further. Hence, in this trial we analyzed pharmacodynamic responses to DAPT and clinical events in CLI patients post PTA. METHODS: In this prospective single center pilot analysis, we included 71 CLI patients. Patients received DAPT after PTA. Antiplatelet effect were measured by light transmission aggregometry (LTA) and vasodilator-stimulated protein phosphorylation assay (VASP). MALE, major adverse cardiac and cerebrovascular events (MACCE) and BARC bleeding within 12 months follow-up were assessed. RESULTS: Mean age of patients was 73.37 ± 7.36 years and 47 (66.2%) were male. Overall HTPR appeared in 46 patients (64.8%). MALE and MACCE showed no differences between patients with and patients without HTPR. However, bleeding was higher in patients with sufficient pharmacodynamic response to DAPT (Bleeding - HTPR: 13.4% vs. no HTPR: 36.0%; log-rank HR: 0.32; 95% CI 0.1079 to 0.9396 p = 0.0217). This finding remained robust in multivariate analysis. CONCLUSION: HTPR to DAPT is frequent in CLI patients. However, bleeding was higher in patients with sufficient response to DAPT. Ischemic events did not differ. Hence, CLI patients might benefit from an alternative antithrombotic approach.

Cocoa Flavanols Improve Endothelial Functional Integrity in Healthy Young and Elderly Subjects.

Cocoa flavanols (CFs) can improve flow-mediated dilation (FMD), blood pressure, and vascular stiffness in healthy subjects. Endothelial microparticles (EMPs) are markers of endothelial functional integrity, reflecting activation and injury. In plasma samples, we investigated whether age-dependent changes in circulating EMPs exist and whether CFs decrease EMPs in healthy humans. The concentrations of CD31+/41-, CD144+, and CD62e+ EMPs (flow cytometry) were increased in healthy elderly (n = 19) compared to young (n = 20) non-smokers. EMPs correlated with age, systolic blood pressure, and pulse wave velocity. CD31+/41- and CD62e+ EMPs inversely correlated with FMD. Following 2 weeks twice-daily CF consumption (450 mg), CD31+/41- and CD144+ EMPs decreased in both young and elderly subjects compared to the CF-free control. The EMP decrease inversely correlated with FMD improvements. Cardiovascular aging is associated with increased EMPs that can be modulated by dietary flavanols along with improvements in vascular function. This indicates that flavanol consumption can improve endothelial functional integrity in healthy humans.

Endovascular Occlusion of a Renal Arteriovenous Fistula with Renal Vein Aneurysm Formation for Rupture Prevention.

PURPOSE: To report the effectiveness of left renal artery (LRA) occlusion using Amplatzer Vascular Plug (AVP) II as treatment for a high-flow renal arteriovenous fistula (RAVF) with multiple renal vein aneurysms (RVA) to prevent aneurysm rupture and cardiac decompensation. CASE REPORT: A 59-year-old female suffering from a post-traumatic RAVF presented with tachycardia and increased cardiac output (CO). Doppler ultrasonography and computed tomography (CT) scan revealed a high-flow RAVF with multiple RVAs and unilateral critically reduced kidney function. Appreciating recent interventional therapeutic advances, the patient was treated with endovascular placement of AVP II into the left renal artery (LRA) resulting in complete occlusion of the RAVF to effectively reduce the risk of RVA rupture and cardiac decompensation. No anti-platelet medication was administrated after the occlusion of the LRA. The patient's physical capacity improved since right heart volume strain was normalized, and CO was reduced. CONCLUSION: Transbrachial AVP II occlusion of the LRA is effective to occlude high-flow RAVFs to prevent risk of life-threatening RVA rupture. Additional follow-up is warranted to verify long-term effectiveness of this approach.

Requirement of ß1 integrin for endothelium-dependent vasodilation and collateral formation in hindlimb ischemia.

An acute increase in blood flow triggers flow-mediated dilation (FMD), which is mainly mediated by endothelial nitric oxide synthase (eNOS). A long-term increase in blood flow chronically enlarges the arterial lumen, a process called arteriogenesis. In several common human diseases, these processes are disrupted for as yet unknown reasons. Here, we asked whether ß1 integrin, a mechanosensory protein in endothelial cells, is required for FMD and arteriogenesis in the ischemic hindlimb. Permanent ligation of the femoral artery in C57BL/6 J mice enlarged pre-existing collateral arteries and increased numbers of arterioles in the thigh. In the lower leg, the numbers of capillaries increased. Notably, injection of ß1 integrin-blocking antibody or tamoxifen-induced endothelial cell-specific deletion of the gene for ß1 integrin (Itgb1) inhibited both arteriogenesis and angiogenesis. Using high frequency ultrasound, we demonstrated that ß1 integrin-blocking antibody or endothelial cell-specific depletion of ß1 integrin attenuated FMD of the femoral artery, and blocking of ß1 integrin function did not further decrease FMD in eNOS-deficient mice. Our data suggest that endothelial ß1 integrin is required for both acute and chronic widening of the arterial lumen in response to hindlimb ischemia, potentially via functional interaction with eNOS.