Risk-adjusted management in catheterization procedures for non-ST-segment elevation myocardial infarction: A standard operating procedure pilot study

BACKGROUND

The effects of standardized risk-adjusted periprocedural management of cardiac catheterization procedures in Non-ST segment elevation myocardial infarction (NSTEMI) remain unknown. We implemented a standard operating procedure (SOP) specifying risk assessment (RA, using National Cardiovascular Data Registry (NCDR) risk models) and risk-adjusted management (RM, e.g. intensified monitoring) in 2018 and aimed to investigate staff SOP adherence and associations with patient outcomes.

METHODS AND RESULTS

All 430 invasively managed NSTEMI patients (mean age 72y; 70.9% male) in 2018 were analyzed for staff SOP adherence and in-hospital clinical outcomes. 207 patients (48.1%; RM+) received both RA and RM; 92 patients (21.4%; RM-) received RA but no RM; 131 patients (30.5%; RA-) received neither RA nor RM. Lower staff adherence to RA was associated with emergency settings (51.9% (RA-) vs. 22.1% (RA+); p<0.01), presentation in cardiogenic shock (17.6% (RA-) vs. 6.4% (RA+); p<0.01) and invasive mechanical ventilation (12.2% (RA-) vs. 3.3% (RA+); p<0.01). Early sheath removal (87.9% (RM+) vs. 56.5% (RM-); p<0.01) and intensified monitoring (p<0.01) were more frequent in the RM+ group. All-cause mortality was not different (1.4% (RM+) vs. 4.3% (RM-); p=0.13), but there were fewer major bleeding events with associated with RM (2.4% (RM+) vs. 12% (RM-); p<0.01), which remained independently associated with RM in a multivariate logistic regression model correcting for confounders (p<0.01).

CONCLUSION

In an all-comer patient cohort with NSTEMI, staff adherence to risk-adjusted periprocedural management was independently associated with fewer major bleeding events. Staff adherence to SOP-specified risk assessment was frequently neglected in more critical clinical situations.

Comparison of costs associated with transcatheter mitral valve repair: PASCAL vs MitraClip in a real-world setting

AIMS

We aimed to conduct a clinical process cost analysis to evaluate all upcoming costs of mitral valve transcatheter edge-to-edge repair (M-TEER) treatment using the MitraClip and the PASCAL repair system.

METHODS

First, we prospectively enrolled 107 M-TEER patients treated with either the PASCAL or MitraClip system and compared all upcoming costs during the M-TEER procedure and the associated in-hospital stay. Second, we retrospectively analysed 716 M-TEER procedures with regard to the occurrence of complications and their associated costs. All materials used in the catheterization laboratory for the procedures were evaluated. The cost analysis considered various expenses, such as general in-hospital costs, device costs, catheter laboratory and material costs.

RESULTS

In the prospective study, 51 patients were treated using the PASCAL system, and 56 were treated using the MitraClip system. The two groups had comparable baseline characteristics and comorbidities. The total in-hospital costs were 25 414 (Interquartile range (IQR) 24 631, 27 697) € in the PASCAL group and 25 633 (IQR 24 752, 28 256) € in the MitraClip group (p = 0.515). The major cost driver was initial material expenditure, mostly triggered by device costs, which were similar to the PASCAL and MitraClip systems. Overall intensive care unit and general ward costs did not differ between the PASCAL and MitraClip groups. In the retrospective analysis, M-TEER-related complications were rare but were associated with higher costs, mainly due to prolonged hospitalisation.

CONCLUSION

The major cost driver of M-TEER was the material expenditure, which was mostly triggered by high device costs. The costs of treating patients were similar for the PASCAL and MitraClip systems. M-TEER-related complications are associated with higher costs, mainly due to prolonged hospitalisation. This analysis provides valuable insights into reducing expenses by modifying the process of M-TEER.

Microvascular tissue perfusion after postcatheterization pseudoaneurysm treatment

BACKGROUND

Femoral pseudoaneurysm (PSA) is a severe complication after endovascular procedures. Ultrasound-guided manual compression (MC) and percutaneous thrombin injection (TI) are frequently used treatments. MC is less effective, TI may cause thromboembolic events.

OBJECTIVE

Up to date, there is no data regarding impairment of microvascular tissue perfusion after PSA treatment.

METHODS

In this single-center, prospective study 22 patients with PSA were included. We compared macro- and microcirculatory perfusion in the treated and untreated leg at baseline before, after and one day after treatment. Leg perfusion was assessed with ultrasound and ankle-brachial index (ABI). Microcirculatory perfusion of the feet was measured with a near-infrared spectroscopy (NIRS) camera generating StO2-tissue-maps.

RESULTS

Successful PSA thrombosis was achieved in 16 (100%) patients in TI group and in 4 (66.7%) patients in MC group. There was no evidence of arterial thrombi on ultrasound and the ABI did not differ between groups. NIRS StO2-tissue-maps of the feet showed no significant difference in both groups concerning the treated (p = 0.121) or the untreated (p = 0.198) leg during follow up.

CONCLUSIONS

In this small exploratory study, there was no evidence of micro- and macrovascular tissue perfusion impairment after treatment of postcatheterization femoral pseudoaneurysm with thrombin injection underscoring the safety of this approach.

Knowledge of HbA1c and LDL-C treatment goals, subjective level of disease-related information and information needs in patients with atherosclerotic cardiovascular disease

BACKGROUND/HYPOTHESIS

Risk factor control of diabetes mellitus (DM) and especially dyslipidemia remains unsatisfactory in patients with atherosclerotic cardiovascular disease (ASCVD). We aimed to analyze the knowledge of low-density lipoprotein cholesterol (LDL-C) and glycated hemoglobin (HbA1c) treatment goals, subjective level of information, and information needs in very high-risk patients with ASCVD.

METHODS

ASCVD patients (n = 210; 75 ± 9 years; 71.4% male; 89.5% coronary disease) with DM (96.7% type 2) completed a questionnaire assessing knowledge of HbA1c and LDL-C treatment goals and subjective level of information and information needs on disease-related topics of DM and ASCVD. Serum LDL-C and HbA1c were measured.

RESULTS

HbA1c goal (<7.0% in 60.6%) was attained more frequently than LDL-C goal (<70 mg/dl in 39.9%; p < .01). Significantly more participants named the correct goal for HbA1c compared to LDL-C (52.9% vs. 2.4%; p < .01). Subjective levels of information were higher and information needs were lower for DM than for ASCVD (p < .01 for all topics). No associations of knowledge of treatment goals and level of information with the attainment of treatment goals for HbA1c and LDL-C were found. However, in multivariate regression, higher levels of education were associated with knowledge of treatment goals (HbA1c: odds ratio [OR] 1.32, 95% confidence interval [CI] 1.01-1.72, p = .04; LDL-C: OR 2.32, 95% CI 1.07-5.03; p = .03).

CONCLUSION

In very high-risk patients with ASCVD, a deficit of knowledge of treatment goals to control dyslipidemia exists when compared to DM, patients felt significantly better informed for topics of DM than for ASCVD and display higher information needs for topics of ASCVD.

Process Standardization in High-Risk Coronary Interventions is Associated With Quality of Care Measures

BACKGROUND

Patient safety is one of the most important issues in healthcare. High-risk percutaneous coronary interventions (HR-PCIs) offer well-established treatment options for patients with complex coronary artery disease and multiple comorbidities. Whether process standardization using standard operating procedure (SOP) management and checklists improves HR-PCI is still unknown.

METHODS AND RESULTS

This retrospective study analyzed procedural characteristics, in-hospital outcomes, and length of hospital stay in patients who received HR-PCI in a German heart center 12 months before the introduction of process standardization using SOP management-the SOP (-) group-and after the introduction of process standardization using SOP management-the SOP (+) group. A total of 192 patients were included, with 77 patients in the SOP (-) group and 115 patients in the SOP (+) group. The mean age in the SOP (-) group was 72.0 ± 10.2 years and 81.8% were male; mean age in the SOP (+) group was 75.2 ± 10.4 years and 68.7% were male. Acute kidney events were significantly lower in the SOP (+) group than in the SOP (-) group (7.0% vs 10.4%; P=.04). Bleeding was the most common adverse event and significantly lower in the SOP (+) group than in the SOP (-) group (13.1% vs 31.2%, respectively; P&lt;.01). There were trends toward shorter length of hospital stay in the SOP (+) group compared with the SOP (-) group (9.3 ± 6.4 days vs 10.9 ± 7.3 days, respectively; P=.10) and days of hospital stay in the intensive care unit (3.7 ± 4.0 days vs 4.7 ± 4.3 days; P=.07). SOP management was independently associated with shorter length of hospital stay in multivariate regression analysis.

CONCLUSION

This retrospective study shows significantly better quality of care measures after the introduction of process standardization techniques using SOP management in HRPCIs, with a lower risk of adverse outcomes and shorter length of hospital stay.

Impact of peripheral angioplasty on wound oxygenation measured with near-infrared spectroscopy in patients with critical limb ischemia

 

Impact of peripheral angioplasty on wound oxygenation measured with near-infrared spectroscopy in patients with critical limb ischemia

Abstract

Background

Near-infrared Spectroscopy (NIRS) has been proposed as a promising noninvasive tool for the assessment of hemoglobin oxygen saturation (StO2) in complex wounds in patients with critical limb ischemia (CLI).

Objective

Up today, NIRS measurements are undertaken at single points near the wound, but not in the wound.

Methods

In this prospective, single center study, 34 patients with PAD Rutherford stage 4–6 were included. We analyzed StO2 maps in and around the wound at baseline one day before and one day after angioplasty using a NIRS camera; macrovascular function was assessed by Doppler ultrasound with spectral analysis including ankle-brachial index (ABI).

Results

Baseline StO2 of the wound area was 63% (± 3.66 [SE]) and 34% in the wound (± 4.8 [SE]). After successful angioplasty, wound area StO2 significantly increased to 71% (± 3.09 [SE]; p&lt;0.001) and wound StO2 increased even more pronounced to 42% (± 4,77 [SE]; p&lt;0.001). Likewise, ABI increased in the treated leg (before 0.74±0.03 [SE]; after 0.87±0.02 [SE]; p=0.008).

Conclusion

This is the first study to assess oxygenation in the wound using a NIRS camera after peripheral angioplasty. NIRS monitoring of wound oxygenation in patients undergoing endovascular treatment is a promising tool to monitor tissue perfusion.

Funding Acknowledgement

Type of funding sources: Public hospital(s). Main funding source(s): Department of Cardiology, Pulmonology, and Vascular Medicine, University Duesseldorf, Medical Faculty, Duesseldorf, Germany

Angioplasty of flow limiting stenosis improves left ventricular diastolic dysfunction in patients with peripheral artery disease

Background

Peripheral artery disease (PAD) is associated with hypertension and left ventricular diastolic dysfunction (LVDD).

Objective

We hypothesized that endovascular treatment of flow limiting peripheral stenosis may improve LVDD.

Methods

In this prospective single center trial, 23 patients with PAD Rutherford stage 2–4 were included. Augmentation index (AIx), central systolic blood pressure (cSBP) and ankle brachial index (ABI) were measured at baseline one day before, one day after and at follow up 4 months after angioplasty. LVDD was assessed by echocardiography at baseline and at follow up.

Results

Mean E/E' ratio was significantly lower at follow up (11.9±4.4 to 10.2±4.4; p&lt;0.01). Likewise, left atrial size (17.2±5.3 to 13.6±4.7 mm; p=0.014) decreased significantly, but not left atrial volume index (LAVI, 49.73±21.6 to 38.29±17.3 mL/m2; p=0.062). ABI acutely increased in the intervened leg and remained stable at follow up (0.71±0.13 to 0.84±0.13 to 0.89±0.18; p&lt;0.001). AIx (from 30.5±6.1 to 26.5±9.2; p=0.03) and cSBP (from 133±21 to 126±20 mmHg; p=0.05) acutely decreased after angioplasty. At follow up, there was no significant change in central hemodynamics (AIx, cSBP) as compared to baseline.

Conclusion

Chronic effects of angioplasty are associated with favorable improvement of diastolic function but not central hemodynamics.

Funding Acknowledgement

Type of funding sources: None.

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.

National Cardiovascular Data Registry-Acute Kidney Injury (NCDR) vs. Mehran risk models for prediction of contrast-induced nephropathy and need for dialysis after coronary angiography in a German patient cohort

BACKGROUND

Contrast-induced nephropathy (CIN) is a major adverse event in patients undergoing coronary angiography. The Mehran risk model is the gold-standard for CIN risk prediction. However, its performance in comparison to more contemporary National Cardiovascular Data Registry-Acute Kidney Injury (NCDR-AKI) risk models remains unknown. We aimed to compare both in this study.

METHODS AND RESULTS

Predictions of Mehran and NCDR-AKI risk models and clinical events of CIN and need for dialysis were assessed in a total of 2067 patients undergoing coronary angiography with or without percutaneous coronary intervention. Risk models were compared regarding discrimination (receiver operating characteristic analysis), net reclassification improvement (NRI) and calibration (graphical and statistical analysis). The NCDR risk model showed superior risk discrimination for predicting CIN (NCDR c-index 0.75, 95% CI 0.72-0.78; vs. Mehran c-index 0.69, 95% CI 0.66-0.72, p < 0.01), and continuous NRI (0.22; 95% CI 0.12-0.32; p < 0.01) compared to the Mehran model. The NCDR risk model tended to underestimate the risk of CIN, while the Mehran model was more evenly calibrated. For the prediction of need for dialysis, NCDR-AKI-D also discriminated risk better (c-index 0.85, 95% CI 0.79-0.91; vs. Mehran c-index 0.75, 95% CI 0.66-0.84; p_NCDRvsMehran < 0.01), but continuous NRI showed no benefit and calibration analysis revealed an underestimation of dialysis risk.

CONCLUSION

In German patients undergoing coronary angiography, the modern NCDR risk model for predicting contrast-induced nephropathy showed superior discrimination compared to the GRACE model while showing less accurate calibration. Results for the outcome 'need for dialysis' were equivocal.

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.

Uninterrupted anticoagulation during catheter ablation for atrial fibrillation: no difference in major bleeding and stroke between direct oral anticoagulants and vitamin K antagonists in an updated meta-analysis of randomised controlled trials

BACKGROUND

Periprocedural uninterrupted anticoagulation for catheter ablation of atrial fibrillation (AF) became standard after positive results of vitamin K antagonist (VKA) trials. Previous studies of uninterrupted direct oral anticoagulants (DOACs) vs. VKA have given controversial results. We thus aimed to elucidate the risk/benefit ratio of uninterrupted DOAC vs. VKA during catheter ablation of AF in an updated meta-analysis of randomised controlled trials (RCTs).

METHODS

Online databases were searched for RCTs comparing uninterrupted DOAC to VKA in patients undergoing catheter ablation of AF. Data from retrieved studies were analysed in a comprehensive meta-analysis. Primary safety outcome was major bleeding; primary efficacy outcome was stroke or transient ischaemic attack (TIA). Secondary outcomes included a composite of major bleeding and stroke or TIA, minor bleeding, acute cerebral lesions on magnetic resonance imaging (MRI), and mortality.

RESULTS

Six eligible RCTs comprising 2,369 patients were included. There were no significant differences in DOAC vs. VKA concerning the rates of major bleeding (2.2% vs. 3.8%; odds ratio (OR) 0.69, 95% confidence interval (CI) 0.30-1.56; p = .37) and stroke or TIA (0.2% vs. 0.2%; OR 0.97, CI 0.20-4.72; p = .97). Pooled meta-analysis of secondary outcomes revealed no significant differences (OR 0.73, p = .49 for composite of major bleeding and stroke or TIA; OR 1.08, p = .52 for minor bleeding; OR 1.12, p = .59 for acute cerebral lesions on MRI; and OR 0.60, p = .64 for all-cause mortality).

CONCLUSION

Our meta-analysis suggests that uninterrupted DOAC is not superior to VKA in patients undergoing catheter ablation of AF with comparable rates of major bleeding and stroke.

Modern NCDR and ACTION risk models outperform the GRACE model for prediction of in-hospital mortality in acute coronary syndrome in a German cohort

BACKGROUND AND PURPOSE

Risk prediction with the Global Registry of Acute Coronary Events (GRACE) risk model is guideline-recommended in acute coronary syndrome (ACS) patients. However, the performance of more contemporary scores derived from ACTION (Acute Coronary Treatment and Intervention Outcomes Network) and National Cardiovascular Data (NCDR) registries remains incompletely understood. We aimed to compare these models in German ACS patients.

METHODS AND RESULTS

A total of 1567 patients with (Non-)ST-segment elevation myocardial infarction (NSTEMI: 1002 patients, STEMI: 565 patients) undergoing invasive management at University Hospital Düsseldorf (Germany) from 2014 to 2018 were included. Overall in-hospital mortality was 7.5% (NSTEMI 3.7%, STEMI 14.5%). Parameters for calculation of GRACE 1.0, GRACE 2.0, ACTION and NCDR risk models and in-hospital mortality were assessed and risk model performance was compared. The GRACE 1.0 risk model for prediction of in-hospital mortality discriminated risk superior (c-index 0.84) to its successor GRACE 2.0 (c-index 0.79, p_{GRACE1.0vsGRACE2.0} = 0.0008). The NCDR model performed best in discrimination of risk in ACS overall (c-index 0.89; p_ACTIONvsNCDR < 0.0001; p_GRACEvsNCDR < 0.0001) and showed superior performance compared to GRACE in NSTEMI and STEMI subgroups (p_GRACEvsNCDR both < 0.02). ACTION and GRACE risk models performed comparable to each other (both c-index 0.84, p_{GRACEvsACTION} = 0.68), with advantages for ACTION in NSTEMI patients (c-index 0.87 vs. 0.84 (GRACE); p_{GRACEvsACTION} = 0.02). ACTION and GRACE 2.0 showed the most accurate calibration of all models.

CONCLUSIONS

In a contemporary German patient population with ACS, modern NCDR and ACTION risk models showed superior performance in prediction of in-hospital mortality compared to the gold-standard GRACE model.

Standardized risk management in catheterization procedures for non-ST-segment elevation myocardial infarction: associations with in-hospital clinical outcomes

Introduction and purpose

Patient risk in non-ST-segment elevation myocardial infarction (NSTEMI) depends on clinical setting, individual patient variables and procedural characteristics. Standardized risk-adjusted periprocedural management for catheterization procedures using a Standard Operating Procedure (SOP) was investigated to evaluate associations with in-hospital clinical outcomes.

Methods

In 01/2018, our heart center established an SOP for coronary catheterization procedures in NSTEMI, targeting 1) standardized pre-procedural risk assessment using National Cardiovascular Data Registry (NCDR) risk models, and 2) standardized post-procedural risk-adjusted safety measures, including advanced patient monitoring (intermediate/intensive care) and use of vascular closure devices. All patients presenting with invasively-managed NSTEMI in 2018 were retrospectively evaluated for SOP-based pre-procedural risk scoring, SOP-based post-procedural management and in-hospital clinical outcomes of mortality, major bleeding (MB, according to BARC ≥3) and acute kidney injury (AKI, according to KDIGO).

Results

A total of 430 patients (age 72±12 years, 71% male, BMI 27±5) presenting with NSTEMI from 01 to 12/2018 were included, 9.8% presented in cardiogenic shock and 4.7% had suffered a preclinical cardiac arrest. Overall in-hospital mortality was 3.7%, MB occurred in 6.5%. 207 patients (48.1%, SOP+ group) had received both 1) pre-procedural risk assessment and 2) post-procedural risk-adjusted safety measures; the other 223 patients (51.9%, SOP- group) had not received either 1) or 2). There were no significant differences in baseline characteristics and prior-existing medical conditions between groups, however, significantly more patients in SOP- group were treated in emergency settings (39.9% vs. 21.7%, p=0.004). However, significantly more patients in SOP- were treated in emergency settings at higher risk (39.9% (SOP-) vs. 21.7% (SOP+); p&lt;0.001). In univariate analysis, all in-hospital clinical outcomes of mortality (1.4% (SOP+) vs. 5.8% (SOP-); p=0.016), MB (2.9% (SOP+) vs. 9.9% (SOP-); p=0.003) and AKI were significantly lower in the SOP+ group (15.9% (SOP+) vs. 24.2% (SOP-); p=0.033). After correction for the difference in risk between groups due to emergency settings by multivariate logistic regression analysis, MB remained significantly lower in SOP+ (p=0.02), while mortality (p=0.14) and AKI (p=0.19) were not significantly associated with SOP-status anymore.

Conclusion

Standardized risk management in invasively managed NSTEMI was associated with significantly lower rates of in-hospital major bleedings.

Funding Acknowledgement

Type of funding source: Private grant(s) and/or Sponsorship. Main funding source(s): Junior Clinician Scientist Track, Medical faculty, Heinrich-Heine-University Düsseldorf, Germany

Uninterrupted direct oral anticoagulants and vitamin K antagonists during ablation for atrial fibrillation: an updated meta-analysis

Background

Uninterrupted anticoagulation during catheter ablation of atrial fibrillation (CAAF) became standard of care after positive results of trials investigating vitamin K antagonists (VKA). Previous studies and meta-analyses of uninterrupted direct oral anticoagulants (DOAC) vs. VKA have given controversial results. We thus aimed to elucidate the risks and benefits of uninterrupted DOAC vs. VKA during CAAF in an updated meta-analysis of randomized controlled trials (RCTs).

Methods

Online databases were searched for RCTs comparing uninterrupted DOAC to VKA in patients undergoing CAAF until September 2019. Data from retrieved studies were analysed in a comprehensive meta-analysis. Primary safety outcome was major bleeding; primary efficacy outcome was stroke or transient ischemic attack (TIA). Secondary outcomes included a composite of major bleeding and stroke or TIA, minor bleeding, acute cerebral lesions on magnetic resonance imaging (ACL) and mortality.

Results

Six eligible RCTs comprising 2,369 patients were included. Pooled meta-analysis showed no significant differences in DOAC vs. VKA concerning the rates of major bleeding (2.2% vs. 3.8%; odds ratio (OR) 0.69, 95% confidence interval (CI) 0.30–1.56; p=0.37) and stroke or TIA (0.2% vs. 0.2%; OR 0.97, CI 0.20–4.72; p=0.97). There were no significant differences found in secondary outcomes (OR 0.73, p=0.49 for composite of major bleeding and stroke or TIA; OR 1.08, p=0.52 for minor bleeding; OR 1.12, p=0.59 for ACL; and OR=0.60, p=0.64 for all-cause mortality).

Conclusion

Our meta-analysis suggests that uninterrupted periprocedural anticoagulation with DOAC or VKA is characterized by a similar risk/benefit ratio in patients undergoing CAAF with comparable rates of major bleeding and stroke.

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): Medical faculty of the Heinrich-Heine-University Düsseldorf, Germany

Kidney function stratified outcomes of percutaneous left atrial appendage occlusion in patients with atrial fibrillation and high bleeding risk

Background: Patients with chronic kidney disease (CKD) and atrial fibrillation have increased risks for stroke and bleeding under oral anticoagulation (OAC). We investigated an alternative therapy of percutaneous left atrial appendage occlusion (LAAO) in CKD patients in this study.Methods: Consecutive patients undergoing LAAO were included in a retrospective analysis and stratified for kidney function into CKD/Non-CKD groups (cutoff eGFR 60 ml/min). Procedural characteristics, in-hospital and follow-up events were analysed and compared between groups.Results: LAAO was performed in 146 patients (81 CKD; 65 Non-CKD), mean follow-up was 391 days. Groups differed in eGFR (40.1 (CKD) vs. 75.1 (Non-CKD) ml/min) and CHA₂DS₂VASc scores (4.65 ± 1.3 (CKD) vs. 4.06 ± 1.4 (Non-CKD)). Procedural success was 98.6%, contrast-induced acute kidney injury was significantly more frequent in CKD patients (11.1% vs. 0%; p = .004). Follow-up mortality was higher in CKD (10.5/100 PY vs. 4.2/100 PY; p = .156). Follow-up stroke rates were 2.3/100 (CKD) patient-years (PY) and 1.4/100 PY (Non-CKD) (p = 1.000), corresponding to a relative risk reduction (RRR) of 60% (all), 68% (CKD) and 71% (Non-CKD) compared to expected stroke rates. Follow-up major bleeding rates were 3.5/100 PY (CKD) and 4.2/100 PY (Non-CKD), corresponding to RRR of 57% (all), 61% (CKD) and 53% (Non-CKD) compared to OAC.Conclusions: Left atrial appendage occlusion shows comparable efficacy for stroke and bleeding prevention in CKD and Non-CKD patients. CKD patients experience more adverse events during follow-up and a significantly increased risk for periprocedural contrast-induced acute kidney injury.

Endovascular Thrombectomy as a Means to Improve Survival in Acute Ischemic Stroke: A Meta-analysis

Importance

Although endovascular thrombectomy (EVT) in acute ischemic stroke is recommended by guidelines to improve functional recovery, thus far there are insufficient data on its association with mortality.

Objective

To identify guideline-relevant trials of EVT vs medical therapy reporting 90-day mortality and perform a meta-analysis.

Data Sources

All randomized clinical trials cited for recommendations on EVT vs medical therapy in the latest 2018 American Stroke Association/American Heart Association guidelines.

Study Selection

Ten American Stroke Association/American Heart Association guideline-relevant randomized clinical trials of EVT vs medical therapy were selected for inclusion. Two EVT trials were excluded owing to infrequent use of EVT.

Data Extraction and Synthesis

Data were abstracted by 2 independent investigators and double-checked by 4 others. Singular study data were integrated using the Cochran-Mantel-Haenszel method and a random-effects model to compute summary statistics of risk ratios (RR) with 95% CIs.

Main Outcomes and Measures

Risk of 90-day mortality and 90-day intracranial hemorrhage was analyzed; sensitivity analyses were performed in early-window EVT trials (which included patients from the onset of symptoms onward) vs late-window EVT trials (which included patients from 6 hours after onset of symptoms onward).

Results

In 10 trials with 2313 patients, EVT significantly reduced the risk for 90-day mortality by 3.7% compared with medical therapy (15.0% vs 18.7%; RR, 0.81; 95% CI, 0.68-0.98; P = .03). Trends were similar in early-window (RR, 0.83; 95% CI, 0.67-1.01; P = .06) and late-window trials only (RR, 0.76; 95% CI, 0.41-1.40; P = .38). There was no difference in the risk for intracranial hemorrhage in EVT vs medical therapy (4.2% vs 4.0%; RR, 1.11; 95% CI, 0.71-1.72; P = .65). Limitations of the studies include trial protocol heterogeneity and bias originating from prematurely terminated trials.

Conclusions and Relevance

This meta-analysis of all evidence on EVT cited in the 2018 American Stroke Association/American Heart Association guidelines shows significant benefits for survival during the first 90 days after acute ischemic stroke compared with medical therapy alone.

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.

[Update ESC-Guideline: Management of cardiovascular diseases during pregnancy - What is important?]

The treatment of pregnant patients with a cardiovascular disease is a special challenge to deal with. Before getting pregnant all cardiac patients should get medical advice accordingly to their risk profile in the modified World Health Organization classification of maternal cardiovascular risk. This article has the aim to give an overview of the new or changed recommendations of the new ESC-Guideline for the management of cardiovascular diseases during pregnancy.

283Endovascular thrombectomy as a means to improve survival in acute ischemic stroke - A meta-analysis

Background and purpose

Although endovascular thrombectomy (EVT) in acute ischemic stroke (AIS) is guideline-recommended to improve functional recovery, thus far there are only inconclusive data from underpowered singular trials of EVT vs. medical therapy (MT) on mortality. We here aimed to perform a meta-analysis on short-term mortality in guideline-relevant EVT vs. MT randomized controlled trials (RCTs).

Methods

All randomized controlled trials (RCT) reporting EVT vs. MT in the latest 2018 American Stroke Association/American Heart Association (ASA/AHA) Guidelines were eligible for inclusion. Data were abstracted by two independent investigators and double-checked by four others. Study data were integrated using the Cochran-Mantel-Haenszel method and a random-effects model to compute summary statistics of risk ratios (RR) with 95% confidence intervals (CI). Ninety-day mortality and intracranial hemorrhage (ICH) were analyzed.

Results

Ten of the twelve guideline-relevant EVT vs. MT RCTs (DAWN, DEFUSE 3, ESCAPE, EXTEND-IA, MR CLEAN, MR RESCUE, REVASCAT, SWIFT PRIME, THERAPY, THRACE) with 2,313 patients were selected for inclusion. Studies IMS III and SYNTHESIS were excluded due to their very infrequent use of EVT. Stent retrievers (Trevo, Solitaire, Merci) were most frequently applied, followed by thrombus aspiration (Penumbra). Intravenous thrombolysis was administered in addition to EVT in the majority of patients. In the pooled meta-analysis of all eligible RCTs, EVT significantly reduced the risk for 90-day mortality by 3.7% compared to MT (15.0% vs. 18.7%; RR 0.81 with CI 0.68 to 0.98; p=0.03), accounting for a number-needed-to-treat of 27 to prevent one all-cause death. Trends were similar in early-window (RR 0.83) and late-window trials only (RR 0.76). There was no difference in the risk for ICH in EVT vs. MT (4.2% vs. 4.0%; RR 1.11 with CI 0.71 to 1.72; p=0.65). All included trials were published in high-quality journals and risk of bias was judged low.

Conclusions

This meta-analysis lends evidence to EVT benefits for survival already during the first 90 days after acute ischemic stroke. These results further highlight the evolution of interventional techniques in this setting.

P6268Cardiovascular outcomes of new anti-diabetic agents - A meta-analysis of randomized controlled trials

Background and purpose

The risk of major cardiovascular events (MACE) is increased in patients with diabetes mellitus. Recently published clinical trials of three different pharmacological classes (DPP4 inhibitors (DPP4i), SGLT2-inhibitors (SGLT2i), GLP-1-receptor-antagonists (GLP1RA)) of new anti-diabetic agents (ADA) showed potential benefits for cardiovascular (CV) outcomes. We thus aimed to perform a meta-analysis of randomized controlled trials (RCTs) of these ADA to elucidate benefits on CV outcomes in diabetic patients.

Methods

Following a systematic online database search, all RCTs reporting CV outcomes of DPP4i, SGLT2i or GLP1RA vs. Placebo in diabetic patients up until December 2018 were eligible for inclusion in the meta-analysis. Studies including patients with acute coronary syndrome (ACS) were excluded. Data were abstracted and analyzed with the inverse-variance method and a random-effects model, hazard ratios (HR) with 95% confidence intervals (CI) were used as summary statistics. CV outcomes of MACE, myocardial infarction (MI), stroke, heart failure (HF), CV death and all-cause mortality were analyzed.

Results

Eleven RCTs (DPP4i: SAVOR, TECOS, CARMELINA; GLP1RA: LEADER, SUSTAIN-6, EXSCEL, Harmony; SGLT2i: EMPA-REG OUTCOME, CANVAS Program, DECLARE) with 109,316 patients were selected for inclusion. ELIXA and EXAMINE were excluded due to their inclusion of patients with ACS, CAROLINA was excluded for lack of placebo-control. In the pooled meta-analysis of all trials, ADA significantly reduced the risk for MACE (Hazard ratio (HR) 0.91, CI 0.86–0.96, p=0.0004), MI (HR 0.91, CI 0.85–0.96, p=0.02), CV death (HR 0.9, CI 0.82–0.99, P=0.02) and all-cause mortality (HR 0.92, CI 0.85–0.99, p=0.03). There was no difference in the risk for stroke (HR 0.94, CI 0.87–1.02, p=0.16) and HF (HR 0.88, CI 0.76–1.02, p=0.08). In agent-specific subgroup analyses, GLP1RA and SGLT2i showed significant reductions in MACE (GLP1RA: HR 0.85, CI 0.78–0.92, p<0.0001; SGLT2i: HR 0.89, CI 0.83–0.96, p=0.001), MI (GLP1RA: HR 0.86, CI 0.76–0.98, p=0.02; SGLT2i: HR 0.88, CI 0.79–0.97, p=0.01) and all-cause mortality (GLP1RA: HR 0.88, CI 0.81–0.95; p=0.001; SGLT2i: HR 0.83, CI 0.70–0.99; p=0.03). GLP1RA significantly reduced risk for stroke (HR 0.85, CI 0.75–0.96, p=0.008) and CV death (HR 0.86, CI 0.78–0.95, p=0.002). SGLT2I were especially effective in the reduction of risk for HF (HR 0.69, CI 0.61–0.79; p<0.0001). DPP4i inhibitors however failed to show superiority in all analyzed outcomes.

Conclusions

This meta-analysis lends evidence to GLP1RA and SGLT2i benefits for MACE, MI and all-cause mortality, while DPP4i failed to show superiority in cardiovascular outcomes. Individualized medication for diabetic patients depending on CV disease status should be considered.

P2792Preoperative levosimendan improves survival in patients with low cardiac output syndrome undergoing cardiac surgery: a meta-analysis of randomized controlled trials

Background and purpose

Previous studies and meta-analyses of perioperative levosimendan to improve the outcomes of patients with low cardiac output syndrome (LCOS) undergoing cardiac surgery have given controversial results and the optimal time of infusion of levosimendan remains uncertain. We thus aimed to elucidate the risk/benefit ratio of preoperative levosimendan in a meta-analysis of randomized controlled trials (RCTs).

Methods

Online databases were searched for RCTs comparing preoperative levosimendan to placebo in patients with LCOS undergoing cardiac surgery until February 2019. Data from retrieved studies were abstracted and analyzed in a comprehensive meta-analysis. Primary outcome was all-cause mortality. Secondary outcomes included myocardial infarction, renal failure/replacement therapy, need for inotropic therapy, need for left ventricular assist devices, ventricular arrhythmia and arterial hypotension.

Results

As a result of the online database search, six eligible RCTs with 1,326 patients were included in the meta-analysis. Preoperative levosimendan showed a significant reduction in all-cause mortality (odds ratio (OR) 0.49, 95% confidence interval (CI) 0.29–0.83; p<0.01), renal failure/replacement therapy (OR 0.48, CI 0.29–0.80; p<0.01) and need for inotropic therapy (OR 0.24, CI 0.06–0.95; p=0.04) compared to placebo. There were no significant differences in levosimendan vs. placebo concerning the rates of myocardial infarction (OR 0.61, p=0.38), need for left ventricular assist devices (OR 0.38, p=0.1), ventricular arrhythmia (OR 0.7, p=0.33), and arterial hypotension (OR 1.28, p=0.07).

Conclusions

Preoperative administration of levosimendan may improve survival in patients with low cardiac output syndrome undergoing cardiac surgery. It reduces need for inotropic medical support and renal failure/replace-ment therapy compared to placebo.

P957Survival benefits of routine glycoprotein IIb/IIIa inhibitors during primary PCI in ST-segment elevation myocardial infarction: A meta-analysis of randomised controlled trials

Background

Cardiovascular guidelines recommend adjunct glycoprotein IIb/IIIa inhibitors (GPI) only in selected patients with acute ST-segment elevation myocardial infarction (STEMI).

Purpose

This study aimed to evaluate routine GPI use in STEMI treated with primary PCI.

Methods

Online databases were systematically searched for randomised controlled trials (RCTs) of routine GPI vs. control therapy in STEMI. Data from retrieved studies were abstracted and evaluated in a comprehensive meta-analysis using Mantel-Haenszel estimates of risk ratios (RR) as summary statistics.

Results

After systematic review, twenty-one RCTs with 8,585 patients were included: ten trials randomized tirofiban (T), nine abciximab (A), one eptifibatide (E), one trial used A+T; only one trial used DAPT with prasugrel/ ticagrelor. Routine GPI were associated with a significant reduction in all-cause mortality at 30 days (2.4% (GPI) vs. 3.2%; risk ratio (RR) 0.72; p=0.01) and 6 months (3.7% vs. 4.8%; RR 0.76; p=0.02), and a reduction in recurrent MI (1.1% vs. 2.1%; RR 0.55; p=0.0006), repeat revascularization (2.5% vs. 4.1%; RR 0.63; p=0.0001), TIMI flow <3 after PCI (5.4% vs. 8.2%; RR 0.61; p<0.0001) and ischemic stroke (RR 0.42; p=0.04). Major (4.7% vs. 3.4%; RR 1.35; p=0.005) and minor bleedings (7.2% vs. 5.1%; RR 1.39; p=0.006) but not intracranial bleedings (0.1% vs. 0%; RR 2.7; p=0.37) were significantly increased under routine GPI.

Conclusions

Routine GPI administration during primary PCI in STEMI resulted in mortality reduction, driven by reductions in recurrent ischemic events – however predominantly in trials pre-prasugrel/ticagrelor. Trials in contemporary STEMI management are needed to confirm these findings.

Routine Glycoprotein IIb/IIIa Inhibitor Therapy in ST-Segment Elevation Myocardial Infarction: A Meta-analysis

BACKGROUND

Guidelines recommend adjunct glycoprotein IIb/IIIa inhibitors (GPIs) only in selected patients with acute ST-segment elevation myocardial infarction (STEMI). This study aimed to evaluate routine GPI use in STEMI treated with primary percutaneous coronary intervention.

METHODS

Online databases were searched for randomized controlled trials of routine GPI vs control therapy in STEMI. Data from retrieved studies were abstracted and evaluated in a comprehensive meta-analysis. Twenty-one randomized controlled trials with 8585 patients were included: 10 trials randomized tirofiban, 9 abciximab, 1 trial eptifibatide, and 1 trial used abciximab+tirofiban; only 1 trial used dual antiplatelet therapy with prasugrel/ticagrelor.

RESULTS

Routine GPI use was associated with a significant reduction in all-cause mortality at 30 days (2.4% [GPI] vs 3.2%; risk ratio [RR], 0.72; P = 0.01) and 6 months (3.7% vs 4.8%; RR, 0.76; P = 0.02), and a reduction in recurrent myocardial infarction (1.1% vs 2.1%; RR, 0.55; P = 0.0006), repeat revascularization (2.5% vs 4.1%; RR, 0.63; P = 0.0001), thrombolysis in myocardial infarction flow <3 after percutaneous coronary intervention (5.4% vs 8.2%; RR, 0.61; P < 0.0001), and ischemic stroke (RR, 0.42; P = 0.04). Major (4.7% vs 3.4%; RR, 1.35; P = 0.005) and minor bleedings (7.2% vs 5.1%; RR, 1.39; P = 0.006) but not intracranial bleedings (0.1% vs 0%; RR, 2.7; P = 0.37) were significantly increased under routine GPI.

CONCLUSIONS

Routine GPI administration in STEMI resulted in a reduction in mortality, driven by reductions in recurrent ischemic events-however predominantly in pre-prasugrel/ticagrelor trials. Trials with contemporary STEMI management are needed to confirm these findings.

Methylxanthines enhance the effects of cocoa flavanols on cardiovascular function: randomized, double-masked controlled studies

BACKGROUND

Cocoa flavanol intake, especially that of (-)-epicatechin, has been linked to beneficial effects on human cardiovascular function. However, cocoa also contains the methylxanthines theobromine and caffeine, which may also affect vascular function.

OBJECTIVE

We sought to determine whether an interaction between cocoa flavanols and methylxanthines exists that influences cocoa flavanol-dependent vascular effects.

DESIGN

Test drinks that contained various amounts of cocoa flavanols (0-820 mg) and methylxanthines (0-220 mg), either together or individually, were consumed by healthy volunteers (n = 47) in 4 different clinical studies-3 with a randomized, double-masked crossover design and 1 with 4 parallel crossover studies. Vascular status was assessed by measuring flow-mediated vasodilation (FMD), brachial pulse wave velocity (bPWV), circulating angiogenic cells (CACs), and blood pressure before and 2 h after the ingestion of test drinks.

RESULTS

Although cocoa flavanol intake increased FMD 2 h after intake, the consumption of cocoa flavanols with methylxanthines resulted in a greater enhancement of FMD. Methylxanthine intake alone did not result in statistically significant changes in FMD. Cocoa flavanol ingestion alone decreased bPWV and diastolic blood pressure and increased CACs. Each of these changes was more pronounced when cocoa flavanols and methylxanthines were ingested together. It is important to note that the area under the curve of the plasma concentration of (-)-epicatechin metabolites over time was higher after the co-ingestion of cocoa flavanols and methylxanthines than after the intake of cocoa flavanols alone. Similar results were obtained when pure (-)-epicatechin and the methylxanthines theobromine and caffeine were consumed together.

CONCLUSION

A substantial interaction between cocoa flavanols and methylxanthines exists at the level of absorption, in which the methylxanthines mediate an increased plasma concentration of (-)-epicatechin metabolites that coincides with enhanced vascular effects commonly ascribed to cocoa flavanol intake. This trial was registered at clinicaltrials.gov as NCT02149238.

Microglial Priming and Alzheimer's Disease: A Possible Role for (Early) Immune Challenges and Epigenetics?

Neuroinflammation is thought to contribute to Alzheimer's disease (AD) pathogenesis that is, to a large extent, mediated by microglia. Given the tight interaction between the immune system and the brain, peripheral immune challenges can profoundly affect brain function. Indeed, both preclinical and clinical studies have indicated that an aberrant inflammatory response can elicit behavioral impairments and cognitive deficits, especially when the brain is in a vulnerable state, e.g., during early development, as a result of aging, or under disease conditions like AD. However, how exactly peripheral immune challenges affect brain function and whether this is mediated by aberrant microglial functioning remains largely elusive. In this review, we hypothesize that: (1) systemic immune challenges occurring during vulnerable periods of life can increase the propensity to induce later cognitive dysfunction and accelerate AD pathology; and (2) that "priming" of microglial cells is instrumental in mediating this vulnerability. We highlight how microglia can be primed by both neonatal infections as well as by aging, two periods of life during which microglial activity is known to be specifically upregulated. Lasting changes in (the ratios of) specific microglial phenotypes can result in an exaggerated pro-inflammatory cytokine response to subsequent inflammatory challenges. While the resulting changes in brain function are initially transient, a continued and/or excess release of such pro-inflammatory cytokines can activate various downstream cellular cascades known to be relevant for AD. Finally, we discuss microglial priming and the aberrant microglial response as potential target for treatment strategies for AD.

Local association between endothelial dysfunction and intimal hyperplasia: relevance in peripheral artery disease

Background

Endothelial dysfunction is a key factor in the development of atherosclerosis. Commonly, endothelial function is determined in the brachial artery, whereas patients with peripheral artery disease (PAD) present with lower limb atherosclerosis. We hypothesized that in PAD, a segmental or local association exists between endothelial dysfunction and atherosclerotic structural changes.

Methods and Results

We used ultrasound to study endothelial function as flow‐mediated vasodilation, intima media thickness, and local stiffness of the superficial femoral artery (SFA) and brachial artery (BA). PAD patients with symptomatic SFA or below‐the‐knee disease were compared with age‐matched patients without PAD and young healthy controls. PAD patients with SFA or below‐the‐knee disease exhibited endothelial dysfunction of the proximal SFA (flow‐mediated vasodilation: 3.9±0.6%, 3.7±0.6%) compared with healthy controls (7.4±1.0%) and patients without PAD (5.4±0.6%). Brachial artery flow‐mediated vasodilation values were not different in PAD patients with SFA or below‐the‐knee disease compared with patients without PAD, but they were significantly lower than those of healthy controls. Endothelial dysfunction correlated with increased intima media thickness or plaque thickness at the site of flow‐mediated vasodilation measurement across vascular sites. In PAD patients with SFA disease, SFA flow‐mediated vasodilation was further impaired within and distal to stenosis (prestenosis 3.9±0.6%, intrastenosis 2.3±0.7%, poststenosis 2.5±0.6%) and recovered within 24 hours after SFA balloon angioplasty to prestenotic values but not to the brachial artery or SFA values in patients without PAD or controls.

Conclusion

A close association exists between local endothelial function and atherosclerotic structural remodeling, suggesting that in PAD, local and segmental factors—in addition to systemic factors—influence local endothelial function. Our data point toward a pathophysiological role for lower extremity endothelial dysfunction in PAD.

Dietary inorganic nitrate mobilizes circulating angiogenic cells

Nitric oxide (NO) was implicated in the regulation of mobilization and function of circulating angiogenic cells (CACs). The supposedly inert anion nitrate, abundant in vegetables, can be stepwise reduced in vivo to form nitrite, and consecutively NO, representing an alternative to endogenous NO formation by NO synthases. This study investigated whether inorganic dietary nitrate influences mobilization of CACs. In a randomized double-blind fashion, healthy volunteers ingested 150 ml water with 0.15 mmol/kg (12.7 mg/kg) of sodium nitrate, an amount corresponding to 100-300 g of a nitrate-rich vegetable, or water alone as control. Mobilization of CACs was determined by the number of CD34(+)/KDR(+) and CD133(+)/KDR(+) cells using flow cytometry and the mobilization markers stem cell factor (SCF) and stromal cell-derived factor-1a (SDF-1α) were determined in plasma via ELISA. Nitrite and nitrate were measured using high-performance liquid chromatography and reductive gas-phase chemiluminescence, respectively. NOS-dependent vasodilation was measured as flow-mediated vasodilation. Further mechanistic studies were performed in mice after intravenous application of nitrite together with an NO scavenger to identify the role of nitrite and NO in CAC mobilization. Nitrate ingestion led to a rise in plasma nitrite together with an acute increase in CD34(+)/KDR(+) and CD133(+)/KDR(+)-CACs along with increased NOS-dependent vasodilation. This was paralleled by an increase in SCF and SDF-1α and the maximal increase in plasma nitrite correlated with CD133(+)/KDR(+)-CACs (r=0.73, P=0.016). In mice, nitrate given per gavage and direct intravenous injection of nitrite led to CAC mobilization, which was abolished by the NO scavenger cPTIO, suggesting that nitrite mediated its effect via formation of NO. Dietary inorganic nitrate acutely mobilizes CACs via serial reduction to nitrite and NO. The nitrate-nitrite-NO pathway could offer a novel nutritional approach for regulation of vascular regenerative processes.

Characterization of macro-and microvascular function and structure in patients with type 2 diabetes mellitus

OBJECTIVE

Diabetes mellitus (DM) leads to accelerated progression of arteriosclerosis with an increased risk of coronary events in comparison to non-diabetic patients with coronary artery disease (CAD). The precise and early detection of DM-induced vascular alterations is crucial to identify patients with high risk for cardiovascular complications. Thus, we aimed at simultaneously characterizing functional, physicomechanical, and structural vascular alterations in diabetic patients using a non-invasive approach.

RESEARCH DESIGN AND METHODS

In CAD patients with and without type 2 diabetes mellitus (n=50), we non-invasively measured flow-mediated dilation (FMD) of the brachial artery as a marker for endothelial function, fractional diameter changes (FDC) as a marker for physicomechanical properties, intima-media thickness (IMT) as a marker for structural properties, and forearm blood flow (FBF) as a marker for microvascular function.

RESULTS

DM was associated with reduced FMD (2.5±0.2 vs 4.8±0.4%; p≤0.001) indicating impaired macrovascular endothelial function. In parallel, reduced FDC (0.024±0.002 vs 0.034±0.004; p≤0.05) and increased IMT (0.38±0.01 vs 0.31±0.01mm; p≤0.001) indicated increased stiffness and enhanced structural alterations. Furthermore, reduced forearm blood flow during reactive hyperemia (10.7±1.0 vs. 15.3±1.4mL/min*100mL; p≤0.05) was found indicating microvascular dysfunction. Plasma glucose and HbA(1c) correlated with FMD (glucose: r=-0.32; HbA(1c): r=-0.45), IMT (glucose: r=0.54; HbA(1c): r=0.48) and FBF (glucose: r=-0.30) suggesting diabetes-specific effects on vascular properties.

CONCLUSION

In patients with CAD, DM leads to functional and structural vascular alterations of the peripheral vasculature which are determined by the control of the disease underlining the relevance of a strict control of the DM to prevent accelerated atherosclerosis.

Nitric oxide synthase expression and functional response to nitric oxide are both important modulators of circulating angiogenic cell response to angiogenic stimuli

OBJECTIVE

Circulating angiogenic cells (CACs), also termed endothelial progenitor cells, play an integral role in vascular repair and are functionally impaired in coronary artery disease (CAD). The role of nitric oxide (NO) in CAC function is poorly understood. We hypothesized that CAC migration toward angiogenic signals is modulated by both NO synthase (NOS) expression and functional response to NO.

METHODS AND RESULTS

Similar to endothelial cells, CAC chemotaxis to vascular endothelial growth factor (VEGF) was blocked by inhibition of NOS, phosphatidylinositol 3-kinase, or guanylyl cyclase or by treatment with an NO scavenger. Addition of an NO donor (S-nitroso-N-acetylpenicillamine) and the NOS substrate l-arginine increased random cell migration (chemokinesis) and enhanced VEGF-dependent chemotaxis. Healthy CACs expressed endothelial NOS, but endothelial NOS was not detected in CAD patient CACs. Both chemokinesis and chemotaxis to VEGF of patient CACs were decreased compared with healthy CACs but were restored to healthy values by S-nitroso-N-acetylpenicillamine. In parallel, CAD patients exhibited lower flow-mediated vasodilation and plasma NO source nitrite than young, healthy subjects, indicating endothelial dysfunction with reduced NO bioavailability.

CONCLUSIONS

NOS activity is required for CAC chemotaxis. In CAD patients, impairment of NOS expression and NO bioavailability, rather than response to NO, may contribute to dysfunction of CACs and limit their regenerative capacity.

Cardioprotection by ischemic postconditioning is lost in aged and STAT3-deficient mice

The cardioprotection by ischemic preconditioning is lost in aged wild-type and in STAT3 (signal transducer and activator of transcription 3)-deficient mice. The aim of the present study was to analyze whether or not ischemic postconditioning (iPoco) was effective in aged mice hearts and whether iPoco was dependent on STAT3. Young (3 months) and aged (>13 months) C57Bl6/J mice underwent 30 minutes of ischemia and 2 hours of reperfusion without or with iPoco (3 cycles of 10 seconds of ischemia/10 seconds of reperfusion [3x10] or 5 cycles of 5 seconds of ischemia/5 seconds of reperfusion [5x5] at the beginning of reperfusion). In young mice, both iPoco3x10 and iPoco5x5 reduced infarct size (IS), whereas in aged mice, only iPoco5x5 was effective in reducing IS. In young mice, iPoco3x10 increased the phosphorylated over total STAT3 (phosphorylated STAT3/STAT3) ratio at 10 minutes of reperfusion in the postconditioned anterior wall compared with the control posterior wall. In aged mice hearts, total STAT3 and phosphorylated STAT3/STAT3 in the anterior wall at reperfusion were reduced compared with young mice hearts. In young mice hearts subjected to iPoco3x10 but pretreated with the JAK-2 inhibitor AG-490, phosphorylated STAT3/STAT3 was reduced in the anterior wall compared with untreated young mice hearts, and IS reduction by iPoco3x10 was abolished. Furthermore, in young mice with a cardiomyocyte-restricted deletion of STAT3, iPoco3x10 failed to reduce IS, whereas iPoco5x5 reduced IS. Thus, cardioprotection by iPoco is dependent on the postconditioning protocol in aged and STAT3-deficient hearts. The reduced levels of STAT3 with increasing age may contribute to the age-related loss of iPoco.

Loss of ischemic preconditioning's cardioprotection in aged mouse hearts is associated with reduced gap junctional and mitochondrial levels of connexin 43

Connexin 43 (Cx43) is localized at left ventricular (LV) gap junctions and in cardiomyocyte mitochondria. A genetically induced reduction of Cx43 as well as blockade of mitochondrial Cx43 import abolishes the infarct size (IS) reduction by ischemic preconditioning (IP). With progressing age, Cx43 content in ventricular and atrial tissue homogenates is reduced. We now investigated whether or not 1) the mitochondrial Cx43 content is reduced in aged mice hearts and 2) IS reduction by IP is lost in aged mice hearts in vivo. Confirming previous results, sarcolemmal Cx43 content was reduced in aged (>13 mo) compared with young (<3 mo) C57Bl/6 mice hearts, whereas the expression levels of protein kinase C epsilon and endothelial nitric oxide synthase remained unchanged. Also in mitochondria isolated from aged mice LV myocardium, Western blot analysis indicated a 40% decrease in Cx43 content compared with mitochondria isolated from young mice hearts. In young mice hearts, IP by one cycle of 10 min ischemia and 10 min reperfusion reduced IS (% of area at risk) following 30 min regional ischemia and 120 min reperfusion from 67.7 +/- 3.3 (n = 17) to 34.2 +/- 6.6 (n = 5, P < 0.05). In contrast, IP's cardioprotection was lost in aged mice hearts, since IS in nonpreconditioned (57.5 +/- 4.0, n = 10) and preconditioned hearts (65.4 +/- 6.3, n = 8, P = not significant) was not different. In conclusion, mitochondrial Cx43 content is decreased in aged mouse hearts. The reduced levels of Cx43 may contribute to the age-related loss of cardioprotection by IP.