Thrombolysis in Myocardial Infarction (TIMI) Trial--phase I: hemorrhagic manifestations and changes in plasma fibrinogen and the fibrinolytic system in patients treated with recombinant tissue plasminogen activator and streptokinase

Impact of Sex on Comparative Outcomes of Radial Versus Femoral Access in Patients With Acute Coronary Syndromes Undergoing Invasive Management: Data From the Randomized MATRIX-Access Trial

OBJECTIVES

This study sought to assess whether transradial access (TRA) compared with transfemoral access (TFA) is associated with consistent outcomes in male and female patients with acute coronary syndrome undergoing invasive management.

BACKGROUND

There are limited and contrasting data about sex disparities for the safety and efficacy of TRA versus TFA for coronary intervention.

METHODS

In the MATRIX (Minimizing Adverse Haemorrhagic Events by TRansradial Access Site and Systemic Implementation of angioX) program, 8,404 patients were randomized to TRA or TFA. The 30-day coprimary outcomes were major adverse cardiovascular and cerebrovascular events (MACCE), defined as death, myocardial infarction, or stroke, and net adverse clinical events (NACE), defined as MACCE or major bleeding.

RESULTS

Among 8,404 patients, 2,232 (26.6%) were women and 6,172 (73.4%) were men. MACCE and NACE were not significantly different between men and women after adjustment, but women had higher risk of access site bleeding (male vs. female rate ratio [RR]: 0.64; p = 0.0016), severe bleeding (RR: 0.17; p = 0.0012), and transfusion (RR: 0.56; p = 0.0089). When comparing radial versus femoral, there was no significant interaction for MACCE and NACE stratified by sex (pint = 0.15 and 0.18, respectively), although for both coprimary endpoints the benefit with TRA was relatively greater in women (RR: 0.73; p = 0.019; and RR: 0.73; p = 0.012, respectively). Similarly, there was no significant interaction between male and female patients for the individual endpoints of all-cause death (pint = 0.79), myocardial infarction (pint = 0.25), stroke (pint = 0.18), and Bleeding Academic Research Consortium type 3 or 5 (pint = 0.45).

CONCLUSIONS

Women showed a higher risk of severe bleeding and access site complications, and radial access was an effective method to reduce these complications as well as composite ischemic and ischemic or bleeding endpoints.

Early clinical outcomes as a function of use of newer oral P2Y12 inhibitors versus clopidogrel in the EUROMAX trial

Objective

To ascertain whether different oral P2Y₁₂ inhibitors might affect rates of acute stent thrombosis and 30-day outcomes after primary percutaneous coronary intervention (pPCI).

Methods

The European Ambulance Acute Coronary Syndrome Angiography (EUROMAX) randomised trial compared prehospital bivalirudin with heparin with optional glycoprotein IIb/IIIa inhibitor treatment in patients with ST-segment elevation myocardial infarction triaged to pPCI. Choice of P2Y₁₂ inhibitor was at the investigator’s discretion. In a prespecified analysis, we compared event rates with clopidogrel and newer oral P2Y₁₂ inhibitors (prasugrel, ticagrelor). Rates of the primary outcome (acute stent thrombosis) were examined as a function of the P2Y₁₂ inhibitor used for loading and 30-day outcomes (including major adverse cardiac events) as a function of the P2Y₁₂ inhibitor used for maintenance therapy. Logistic regression was used to adjust for differences in baseline characteristics.

Results

Prasugrel or ticagrelor was given as the loading P2Y₁₂ inhibitor in 49% of 2198 patients and as a maintenance therapy in 59%. No differences were observed in rates of acute stent thrombosis for clopidogrel versus newer P2Y₁₂ inhibitors (adjusted OR 0.50, 95% CI 0.13 to 1.85). After adjustment, no difference was observed in 30-day outcomes according to maintenance therapy except for protocol major (p=0.029) or minor (p=0.025) bleeding and Thrombolysis In Myocardial Infarction minor bleeding (p=0.002), which were less frequent in patients on clopidogrel. Consistent results were observed in the bivalirudin and heparin arms.

Conclusions

The choice of prasugrel or ticagrelor over clopidogrel was not associated with differences in acute stent thrombosis or 30-day ischaemic outcomes after pPCI.

Trial registration number

NCT01087723.

Impact of Post-Exodontia Bleeding in Cardiovascular Patients: A New Classification Proposal

Background:

Exodontia (dental extraction), being the most frequent minor surgical procedure in the general population, inevitably involves a large number of patients on antithrombotic medication. Current experience shows that there is a degree of confusion in managing these patients.

Description:

Post-exodontia bleeding, a natural consequence of every dental extraction with no or minor clinical significance in the vast majority of cases, often appears to be of major concern to both patients and healthcare practitioners (dentists or physicians), either because of the alarming nature of oral bleeding itself or because of the distorted perception about its importance. These concerns are enhanced by the lack of a universal standardized definition of post-exodontia bleeding and by the fact that all currently available post-exodontia bleeding definitions bear intrinsic limitations and tend to overestimate its clinical significance.

Conclusion:

In order to overcome the aforementioned issues, this article presents an overview of post-extraction bleeding and proposes a classification, based on the well-recognized Bleeding Academic Research Consortium (BARC) bleeding definition, aiming at reducing heterogeneity in this field.

Performance of Anti-Factor Xa Versus Activated Partial Thromboplastin Time for Heparin Monitoring Using Multiple Nomograms

The purpose of this study was to compare the performance of anti-factor Xa concentration versus activated partial thromboplastin time (aPTT) monitoring with multiple indication-specific heparin nomograms. This was a prospective, nonrandomized study with historical control at a large academic medical center. A total of 201 patients who received intravenous heparin in the cardiology units were included. The prospective cohort included patients (n = 101) with anti-factor Xa (anti-Xa) monitoring, and the historical control group included patients (n = 100) who had aPTT monitoring. Patients in the prospective group had both anti-Xa and aPTT samples drawn, but anti-Xa was used for dosing adjustment. The anti-Xa cohort achieved a significantly faster time to therapeutic range (P < .01) and required fewer dose adjustments per 24-hour period compared to the aPTT control (P = .01). Results were consistent across heparin nomograms. The overall discordance rate between the 2 tests was 49%. No significant differences in clinical outcomes were observed. In summary, anti-Xa monitoring improved the time to therapeutic anticoagulation and led to fewer dose adjustments compared to the aPTT with multiple indication-based heparin nomograms.

Early ambulance initiation versus in-hospital initiation of high dose clopidogrel in ST-segment elevation myocardial infarction

Pre-hospital infarct diagnosis gives the opportunity to start anti-platelet and anti-thrombotic agents before arrival at the PCI centre. However, more evidence is necessary to demonstrate whether high dose (HD) clopidogrel (600 mg) administered in the ambulance is associated with improved initial patency of the infarct related vessel (IRV) and/or clinical outcome compared to in-hospital initiation of HD clopidogrel. From 2001 until 2009 all consecutive ST-Segment Elevation Myocardial Infarction (STEMI) patients who underwent pre-hospital diagnosis and therapy in the ambulance were prospectively included in our single-centre cohort study. We compared initial patency of the IRV and clinical outcome in patients treated from 2001 until June 2006 (in-hospital HD clopidogrel) with patients treated from July 2006 until 2009 (ambulance HD clopidogrel). A total of 2,475 patients with STEMI were registered; of these 1,110 (44.8%) received in-hospital HD clopidogrel and 1,365 (55.2%) received ambulance HD clopidogrel. Ambulance HD clopidogrel was not independently associated with initial patency (TIMI-2/3-flow pre-PCI (odds ratio: 1.18, 95% confidence interval [CI] 0.96–1.44); however, it was associated with fewer recurrent myocardial infarctions at 30 days (hazard ratio [HR]: 0.45, 95% CI 0.22–0.93) and at one year (HR: 0.45, 95% CI 0.25–0.80). No difference in TIMI 2/3 flow post-PCI, major bleeding, mortality, MACE – and the combination of mortality and recurrent myocardial infarction at 30-days and at one year was present between the two groups. In conclusion, early in-ambulance as compared to in-hospital initiation of HD clopidogrel in STEMI patients did not improve initial patency of the IRV or clinical outcome, except for a reduction of recurrent myocardial infarction. Therefore, early administration of HD clopidogrel seems to have net clinical benefit for these patients .

Radial versus femoral access in patients with acute coronary syndromes with or without ST-segment elevation

Aims

To assess whether radial compared with femoral access is associated with consistent outcomes in patients with ST-segment elevation myocardial infarction (STEMI) and non-ST-segment elevation acute coronary syndrome (NSTE-ACS).

Methods and results

In the Minimizing Adverse Haemorrhagic Events by TRansradial Access Site and Systemic Implementation of angioX (MATRIX) programme patients were randomized to radial or femoral access, stratified by STEMI (2001 radial, 2009 femoral) and NSTE-ACS (2196 radial, 2198 femoral). The 30-day co-primary outcomes were major adverse cardiovascular events (MACE), defined as death, myocardial infarction, or stroke, and net adverse clinical events (NACE), defined as MACE or major bleeding In the overall study population, radial access reduced the NACE but not MACE endpoint at the prespecified 0.025 alpha. MACE occurred in 121 (6.1%) STEMI patients with radial access vs. 126 (6.3%) patients with femoral access [rate ratio (RR) = 0.96, 95% CI = 0.75-1.24; P = 0.76] and in 248 (11.3%) NSTE-ACS patients with radial access vs. 303 (13.9%) with femoral access (RR = 0.80, 95% CI = 0.67-0.96; P = 0.016) (Pint = 0.25). NACE occurred in 142 (7.2%) STEMI patients with radial access and in 165 (8.3%) patients with femoral access (RR = 0.86, 95% CI = 0.68-1.08; P = 0.18) and in 268 (12.2%) NSTE-ACS patients with radial access compared with 321 (14.7%) with femoral access (RR = 0.82, 95% CI = 0.69-0.97; P = 0.023) (Pint = 0.76). All-cause mortality and access site-actionable bleeding favoured radial access irrespective of ACS type (Pint = 0.11 and Pint = 0.36, respectively).

Conclusion

Radial as compared with femoral access provided consistent benefit across the whole spectrum of patients with ACS, without evidence that type of presenting syndrome affected the results of the random access allocation.

Feasibility of coronary fractional flow reserve with dual anti-platelet therapy in low risk coronary lesions without systemic anticoagulation-results of the SMART-FFR study

BACKGROUND

Fractional flow reserve (FFR) is used to assess the functional significance of coronary artery stenoses. The optimal anti-thrombotic regimen for FFR has not been studied.

PURPOSE

The goal of this study was to determine whether FFR could be safely performed in Type A coronary lesions, using only upstream dual anti-platelet therapy (DAT) with aspirin and clopidogrel, compared with DAT plus anticoagulation in low risk coronary lesions.

METHODS/MATERIALS

Two hundred patients undergoing FFR for Type A intermediate coronary lesions were blindly randomized into two groups of 100 patients each. Group 1: Upstream DAT, without intra-procedural anti-coagulation and Group 2: Upstream DAT plus intra-procedural bivalirudin. The primary end-points were any coronary thrombotic complications during the index hospital stay, and a composite end-point of any major adverse cardiovascular events (MACE) at 30-days. Secondary end-points included post-procedure troponin levels and TIMI major and minor bleeding scores.

RESULTS

There were no thrombotic complications reported. At 30-days, two MACE occurred in Group 1, and three in Group 2 (p=0.83). No difference was seen in the post-procedure troponin levels (p=0.72), or TIMI bleeding scores study between groups (p=093).

CONCLUSIONS

This initial study evaluating a simplified anti-thrombotic regimen for FFR, suggests that FFR can be performed in low risk coronary lesions using DAT without the need for intra-procedural anticoagulation, with similar results as DAT plus anticoagulation with bivalirudin. Further research in this area is needed to determine the optimal and most cost-effective anti-thrombotic regimen for FFR calculation.

Antithrombotic strategies in the catheterization laboratory for patients with acute coronary syndromes undergoing percutaneous coronary interventions: insights from the EmploYEd antithrombotic therapies in patients with acute coronary Syndromes HOspitalized in iTalian cardiac care units Registry

AIMS

In the last decades, several new therapies have emerged for the treatment of acute coronary syndromes (ACS). We sought to describe real-world patterns of use of antithrombotic treatments in the catheterization laboratory for ACS patients undergoing percutaneous coronary interventions (PCI).

METHODS

EmploYEd antithrombotic therapies in patients with acute coronary Syndromes HOspitalized in iTalian cardiac care units was a nationwide, prospective registry aimed to evaluate antithrombotic strategies employed in ACS patients in Italy.

RESULTS

Over a 3-week period, a total of 2585 consecutive ACS patients have been enrolled in 203 cardiac care units across Italy. Among these patients, 1755 underwent PCI (923 with ST-elevation myocardial infarction and 832 with non-ST-elevation ACS). In the catheterization laboratory, unfractioned heparin was the most used antithrombotic drug in both ST-elevation myocardial infarction (64.7%) and non-ST-elevation ACS (77.5%) undergoing PCI and, as aspirin, bivalirudin and glycoprotein IIb/IIIa inhibitors (GPIs) more frequently employed before or during PCI compared with the postprocedural period. Any crossover of heparin therapy occurred in 36.0% of cases, whereas switching from one P2Y12 inhibitor to another occurred in 3.7% of patients. Multivariable analysis yielded several independent predictors of GPIs and of bivalirudin use in the catheterization laboratory, mainly related to clinical presentation, PCI complexity and presence of complications during the procedure.

CONCLUSION

In our contemporary, nationwide, all-comers cohort of ACS patients undergoing PCI, antithrombotic therapies were commonly initiated before the catheterization laboratory. In the periprocedural period, the most frequently employed drugs were unfractioned heparin, leading to a high rate of crossover, followed by GPIs and bivalirudin, mainly used during complex PCI.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT02015624.

Early Invasive Versus Initially Conservative Strategy in Elderly Patients Older Than 75 Years with Non-ST-Elevation Acute Coronary Syndrome: A Meta-Analysis

BACKGROUND

Fear of complications related to the procedure and unclear benefits in elderly patients are common reasons for invasive angiography being withheld.

METHODS

We searched PubMed and Embase from inception until February 2016 for studies that enrolled individuals older than 75 years with non-ST-elevation acute coronary syndrome (NSTE-ACS) and allocated patients to either an invasive or conservative strategy.

RESULTS

Thirteen studies (four randomised controlled trials (RCTs) and nine observational studies) enrolling 832,007 elderly NSTE-ACS patients were analysed. Compared with the conservative treatment, the early invasive approach does significantly reduce the risk of death at follow-up from 6 months to 5 years (risk ratio [RR] 0.65, 95% confidence interval [CI] 0.59-0.73, p<0.001); the definite benefit was mainly observed in observational studies (RR 0.63, 95% CI 0.57-0.70, p<0.001), and the risk of death also showed a strong trend toward reduction with invasive approach (RR 0.82, 95% CI 0.64-1.05, p=0.119) in RCTs. For the outcome of bleeding complications, there was a higher risk of any bleeding occurring in-hospital (RR 2.51, 95% CI 1.53-4.11, p<0.001) in patients treated with invasive strategy than those treated with conservative strategy. However, no difference of in-hospital major bleeding (RR 1.78, 95% CI 0.31-10.13, p=0.514) was observed between the two strategies.

CONCLUSION

Elderly patients with NSTE-ACS might benefit from an early invasive strategy but with increasing risk of any bleeding complications. More RCTs are needed to assess early invasive strategies in the elderly.

Individualized dual antiplatelet therapy based on platelet function testing in patients undergoing percutaneous coronary intervention: a meta-analysis of randomized controlled trials

Background

High on-treatment platelet reactivity (HPR) represents a strong risk factor for thrombotic events after PCI. We aim to evaluate the efficacy and safety of individualizing intensified dual antiplatelet therapy (DAPT) in PCI-treated patients with HPR based on platelet function testing (PFT).

Methods

Electronic databases were searched for randomized control trials that reported the clinical outcomes of using an intensified antiplatelet protocol with P2Y₁₂ receptor inhibitor comparing with standard maintenance dose of clopidogrel on the basis of platelet function testing. Clinical endpoints were assessed.

Results

From 2005 to 2016, thirteen clinical studies comprising 7290 patients were included for analysis. Compared with standard antiplatelet therapy with clopidogrel, the intensified protocol based on platelet function testing was associated with a significant reduction in major adverse cardiovascular events (RR:0.55, 95% CI: 0.36–0.84, p = 0.005), cardiovascular death (RR:0.60, 95% CI: 0.38–0.96, p = 0.03), stent thrombosis (RR:0.58, 95% CI: 0.36–0.93, p = 0.02) and target vessel revascularization (RR:0.33, 95% CI: 0.14–0.76, p = 0.009). No significant difference was found in the rate of bleeding events between intensified and standard protocol.

Conclusions

Compared with standard clopidogrel therapy, individualized intensified antiplatelet therapy on the basis of platelet reactivity testing reduces the incidence of cardiovascular events in patient undergoing PCI, without increasing the risk of bleeding.

Electronic supplementary material

The online version of this article (doi:10.1186/s12872-017-0582-6) contains supplementary material, which is available to authorized users.

Validation of BARC Bleeding Criteria in Patients With Acute Coronary Syndromes: The TRACER Trial

BACKGROUND

The Bleeding Academic Research Consortium (BARC) scale has been proposed to standardize bleeding endpoint definitions and reporting in cardiovascular trials. Validation in large cohorts of patients is needed.

OBJECTIVES

This study sought to investigate the relationship between BARC-classified bleeding and mortality and compared its prognostic value against 2 validated bleeding scales: TIMI (Thrombolysis In Myocardial Infarction) and GUSTO (Global Use of Strategies to Open Occluded Arteries).

METHODS

We analyzed bleeding in 12,944 patients with acute coronary syndromes without ST-segment elevation, with or without early invasive strategy. The main outcome measure was all-cause death.

RESULTS

During follow-up (median: 502 days), noncoronary artery bypass graft (CABG) bleeding occurred in 1,998 (15.4%) patients according to BARC (grades 2, 3, or 5), 484 (3.7%) patients according to TIMI minor/major, and 514 (4.0%) patients according to GUSTO moderate/severe criteria. CABG-related bleeding (BARC 4) occurred in 155 (1.2%) patients. Patients with BARC (2, 3, or 4) bleeding had a significant increase in risk of death versus patients without bleeding (BARC 0 or 1); the hazard was highest in the 30 days after bleeding (hazard ratio: 7.35; 95% confidence interval: 5.59 to 9.68; p < 0.0001) and remained significant up to 1 year. The hazard of mortality increased progressively with non-CABG BARC grades. BARC 4 bleeds were significantly associated with mortality within 30 days (hazard ratio: 10.05; 95% confidence interval: 5.41 to 18.69; p < 0.0001), but not thereafter. Inclusion of BARC (2, 3, or 4) bleeding in the 1-year mortality model with baseline characteristics improved it to an extent comparable to TIMI minor/major and GUSTO moderate/severe bleeding.

CONCLUSIONS

In patients with acute coronary syndromes without ST-segment elevation, bleeding assessed with the BARC scale was significantly associated with risk of subsequent death up to 1 year after the event and risk of mortality increased gradually with higher BARC grades. Our results support adoption of the BARC bleeding scale in ACS clinical trials. (Trial to Assess the Effects of Vorapaxar [SCH 530348; MK-5348] in Preventing Heart Attack and Stroke in Participants With Acute Coronary Syndrome [TRACER] [Study P04736]; NCT00527943).

Efficacy and safety of eptifibatide versus tirofiban in acute coronary syndrome patients: A systematic review and meta-analysis

BACKGROUND

Glycoprotein IIb/IIIa inhibitors were the strongest available antiplatelet therapy and have been shown to reduce cardiac ischemic complications in patients undergoing percutaneous coronary intervention. However, evidences are still lacking on the superiority of eptifibatide over tirofiban or vice versa in patients with acute coronary syndrome.

OBJECTIVE

To compare the efficacy and safety of eptifibatide and tirofiban used among patients with acute coronary syndrome by performing a systematic review and meta-analysis of randomized controlled trials.

METHODS

A systematic search was conducted in Pubmed, Ovid/Medline, Ovid/Embase, Clinicaltrials.gov, CBM and CNKI to identify randomized controlled trials comparing eptifibatide with tirofiban for acute coronary syndrome until November 2015. The methodological quality was assessed with the Cochrane bias risk assessment tool.

RESULTS

1256 patients from 9 randomized controlled trials were finally included. Compared with tirofiban, eptifibatide could reduce more risk of thrombolysis in myocardial infarction minor bleeding (RR 0.61, 95%CI 0.38, 0.98). However, no significant differences were observed for major adverse cardiac events (RR 0.41, 95%CI 0.15 to 1.12), major bleeding, thrombocytopenia in the two treatment groups. The relative treatment benefits were similar in subgroups of patients according to types of acute coronary syndrome, or undergoing percutaneous coronary intervention.

CONCLUSION

Available evidence suggests that the safety of eptifibatide is slightly superior to tirofiban in patients with acute coronary syndrome, but no significant difference was observed on efficacy. Future studies should focus on the randomized controlled trials with larger sample, multi-center, long-term follow-up, high quality to compare the two drugs.

Comparative Effectiveness and Safety Analysis of Dual Antiplatelet Therapies Within an Integrated Delivery System

BACKGROUND

Dual antiplatelet therapy is a mainstay of care for percutaneous coronary intervention (PCI) patients; however, uncertainty exists in real-world practice about comparative effectiveness and safety outcomes.

OBJECTIVE

To evaluate outcomes of different oral P2Y12 inhibitors in PCI patients.

METHODS

We retrospectively studied patients treated between July 1, 2010, and December 31, 2013. Patients received clopidogrel, prasugrel, ticagrelor, or more than 1 antiplatelet (switch) during PCI. Outcomes were evaluated for major adverse cardiovascular events (MACE) and bleeding at 1 year. Propensity score matching with Cox proportional hazards analysis was used to determine predictors of MACE and bleeding.

RESULTS

A total of 8127 patients were included: clopidogrel (n = 6872), prasugrel (n = 605), ticagrelor (n = 181), and switch (n = 469). Treatment with prasugrel was associated with the lowest risk of MACE using multivariate regression (odds ratio [OR] = 0.57; 95% CI = 0.36-0.92; P = 0.02). In the propensity score-matched analysis, only the prasugrel group was associated with a lower risk of MACE compared with the clopidogrel group. Clopidogrel was associated with the lowest risk of major bleeding using multivariate regression (OR = 0.64; 95% CI = 0.42-0.98; P = 0.042). Both ticagrelor (hazard ratio [HR] = 2.00; 95% CI = 1.11-3.59) and the switch groups (HR = 1.65; 95% CI = 1.09-2.50) were associated with a greater risk of major bleeding compared with clopidogrel. However, no differences were found in the propensity score-matched analysis.

CONCLUSIONS

Dual antiplatelet therapies differed in both MACE and bleeds in a real-world setting of PCI. Prasugrel was associated with fewer MACE, whereas clopidogrel had fewer major bleeding events.

Deferred Versus Immediate Stenting in Patients With ST-Segment Elevation Myocardial Infarction: A Systematic Review and Meta-Analysis

Background

A number of studies have evaluated the efficacy of deferred stenting vs immediate stenting in patients with ST‐segment elevation myocardial infarction, but the findings were not consistent across these studies. This meta‐analysis aims to assess optimal treatment strategies in patient with ST‐segment elevation myocardial infarction.

Methods and Results

We searched the PubMed, EMBASE, and the Cochrane Library for studies that assessed deferred vs immediate stenting in patients with ST‐segment elevation myocardial infarction. Nine studies including 1456 patients in randomized controlled trials and 719 patients in observational studies were included in the meta‐analysis. No significant differences were observed in the incidence of no‐ or slow‐reflow between deferred stenting and immediate stenting in randomized controlled trials (odds ratio [OR] 0.51, 95%CI 0.17‐1.53, P=0.23, I²=70%) but not in observational studies (OR 0.13, 95%CI 0.06‐0.31, P<0.0001, I²=0%). Deferred stenting was associated with an increase in long‐term left ventricular ejection fraction (weighted mean difference 1.90%, 95%CI 0.77‐3.03, P=0.001, I²=0%). No significant differences were observed in the rates of major adverse cardiovascular events (OR 0.53, 95%CI 0.27‐1.01, P=0.06 [randomized OR 0.98, 95%CI 0.73‐1.30, P=0.87, I²=0%; nonrandomized OR 0.30, 95%CI 0.15‐0.58, P=0.0004, I²=0%]), major bleeding (OR=0.1.61, 95%CI 0.70‐3.69, P=0.26, I²=0%), death (OR=0.78, 95%CI 0.53‐1.15, P=0.22, I²=0%), MI (OR=0.97, 95%CI 0.34‐2.78, P=0.96, I²=35%) and target vessel revascularization (OR 0.97, 95%CI 0.40‐2.37, P=0.95, I²=24%), between deferred and immediate stenting.

Conclusions

Compared with immediate stenting, a deferred‐stenting strategy did not reduce the occurrence of no‐ or slow‐reflow, death, myocardial infarction, or repeat revascularization compared with immediate stenting in patients with ST‐segment elevation myocardial infarction, but showed an improved left ventricular function in the long term.

Validation of Bleeding Classifications in Coronary Artery Bypass Grafting

Perioperative bleeding is a determinant of poor outcome in patients undergoing coronary artery bypass grafting (CABG), but there is a lack of adequate stratification of its severity. The ability of the European registry of Coronary Artery Bypass Grafting (E-CABG), Universal Definition of Perioperative Bleeding (UDPB), Study of Platelet Inhibition and Patient Outcomes (PLATO), Clopidogrel and Aspirin Optimal Dose Usage to Reduce Recurrent Events-Seventh Organization to Assess Strategies in Ischemic Syndromes (CURRENT-OASIS 7), Efficacy and Safety of Subcutaneous Enoxaparin in Non-Q Wave Coronary Events (ESSENCE), and SafeTy and Efficacy of Enoxaparin in Percutaneous coronary intervention patients, an internationaL randomized Evaluation (STEEPLE) bleeding classifications to predict early mortality, stroke, acute kidney injury (AKI) stage 3, and deep sternal wound infection/mediastinitis was investigated in 3,730 patients from the prospective, multicentre E-CABG registry. Increasing grades of the E-CABG, UDPB, PLATO, and CURRENT-OASIS 7 classifications were associated with increasing risks of early mortality, had similar receiver-operating characteristic area under the curves (>0.7), and were predictive also when adjusted for EuroSCORE II. The E-CABG and UDPB classifications had satisfactory area under the curves (>0.6) in predicting stroke, AKI stage 3, and deep sternal wound infection/mediastinitis even when adjusted for EuroSCORE II. The PLATO and CURRENT-OASIS 7 classifications had similar predictive ability for stroke and AKI stage 3 as confirmed by multivariate analysis adjusted for EuroSCORE II but showed inferior ability in predicting severe wound infection compared to the E-CABG and UDPB classifications. The STEEPLE and ESSENCE classifications had a poor ability of predicting all these adverse events. Decision curve analysis showed a benefit of the E-CABG bleeding classification over the other classifications in predicting all adverse events. In conclusion, the E-CABG, UDPB, PLATO, and CURRENT-OASIS 7 bleeding classifications have a satisfactory ability in predicting adverse events after CABG. Decision curve analysis showed that the E-CABG bleeding classification had the best predictive performance.

Sex differences in the management of acute coronary syndromes in Italy: data from the MANTRA registry

AIMS

Several studies have shown sex differences in acute coronary syndromes (ACS), but their understanding is far from complete. Thus, the study aims to evaluate sex differences in management and outcomes of unselected patients with ACS.

METHODS AND RESULTS

From 22 April 2009 to 29 December 2010, 6394 consecutive patients with ACS (44.7% ST-elevation myocardial infarction) were prospectively enrolled and followed for 6 months. Women (N = 1894, 29.6%) were older, had more comorbidities, and worse clinical presentation than men. Fewer women underwent reperfusion [68.0% women vs. 84.1% men, P < 0.0001, adjusted odds ratio (OR): 0.53, 95% confidence interval (CI): 0.43-0.66] in ST-elevation myocardial infarction, and coronary angiography during hospitalization (72.2% women vs. 81.1% men, P < 0.0001, adjusted OR: 0.70, 95% CI: 0.57-0.85) in no-ST-elevation ACS. Women had worse outcomes than men during hospitalization, and at 6-month follow-up. At multivariable analysis, female sex was significantly associated with a higher risk of in-hospital Thrombolysis in Myocardial Infarction major bleedings (OR: 1.80, 95% CI: 1.09-2.96, P = 0.02), but not of 6-month death.

CONCLUSION

Women with ACS in clinical practice present a clustering of high-risk features that may contribute to their worse outcomes as compared with men, although female sex is not an independent predictor of death at 6-month follow-up.

Hemorrhagic and ischemic outcomes of Heparin vs. Bivalirudin in carotid artery stenting: A meta-analysis of studies

INTRODUCTION

Bivalirudin, has been shown to have comparable efficacy and better safety profile when compared to unfractionated heparin (UFH) in percutaneous coronary interventions. Bivalirudin's safety in carotid artery stenting (CAS) was associated with better outcomes than heparin in some studies. In this Meta analysis we examine the hemorrhagic and ischemic outcomes associated with Bivalirudin compared to UFH during CAS.

METHODS

A comprehensive literature search was conducted with the electronic databases MEDLINE, EMBASE, and CENTRAL. Random-effects meta-analysis method was used to pool risk ratio (RR) for both Heparin and Bivalirudin with 95% confidence interval (CI). Study outcomes included hemorrhagic complications; major/minor bleeding and intracranial hemorrhage (ICH) as well as ischemic complications including ischemic stroke, myocardial infarction, and 30 day mortality.

RESULTS

A total of four studies were included enrolling 7,784 patients. Compared to UFH, Bivalirudin was associated with significantly lower major bleeding events with a relative risk (RR) of 0.53 (95% CI: 0.35-0.80; I²  = 0%). Minor bleeding events were significantly lower in the Bivalirudin group with a RR of 0.41 (95% CI: 0.2-0.82; I²  = 0%). Looking into other outcomes, there were no significant differences between anticoagulation strategies in terms of ischemic stroke (RR 0.8, with 95% CI: 0.60-1.06), intracranial hemorrhage (RR 0.73 with 95% CI: 0.27-1.98), myocardial infarction (RR 1.01 with 95% CI: 0.59-1.73) or 30 day mortality (RR 0.83 with 95% CI: 0.47-1.47).

CONCLUSION

Compared to UFH, Bivalirudin is associated with lower bleeding risk when used during CAS. © 2016 Wiley Periodicals, Inc.

Releasing the Brakes on the Fibrinolytic System in Pulmonary Emboli: Unique Effects of Plasminogen Activation and α2-Antiplasmin Inactivation

BACKGROUND

In patients with hemodynamically significant pulmonary embolism, physiological fibrinolysis fails to dissolve thrombi acutely and r-tPA (recombinant tissue-type plasminogen activator) therapy may be required, despite its bleeding risk. To examine potential mechanisms, we analyzed the expression of key fibrinolytic molecules in experimental pulmonary emboli, assessed the contribution of α2-antiplasmin to fibrinolytic failure, and compared the effects of plasminogen activation and α2-antiplasmin inactivation on experimental thrombus dissolution and bleeding.

METHODS

Pulmonary embolism was induced by jugular vein infusion of ¹²⁵I-fibrin or fluorescein isothiocyanate-fibrin labeled emboli in anesthetized mice. Thrombus site expression of key fibrinolytic molecules was determined by immunofluorescence staining. The effects of r-tPA and α2-antiplasmin inactivation on fibrinolysis and bleeding were examined in a humanized model of pulmonary embolism.

RESULTS

The plasminogen activation and plasmin inhibition system assembled at the site of acute pulmonary emboli in vivo. Thrombus dissolution was markedly accelerated in mice with normal α2-antiplasmin levels treated with an α2-antiplasmin-inactivating antibody (P<0.0001). Dissolution of pulmonary emboli by α2-antiplasmin inactivation alone was comparable to 3 mg/kg r-tPA. Low-dose r-tPA alone did not dissolve emboli, but was synergistic with α2-antiplasmin inactivation, causing more embolus dissolution than clinical-dose r-tPA alone (P<0.001) or α2-antiplasmin inactivation alone (P<0.001). Despite greater thrombus dissolution, α2-antiplasmin inactivation alone, or in combination with low-dose r-tPA, did not lead to fibrinogen degradation, did not cause bleeding (versus controls), and caused less bleeding than clinical-dose r-tPA (P<0.001).

CONCLUSIONS

Although the fibrinolytic system assembles at the site of pulmonary emboli, thrombus dissolution is halted by α2-antiplasmin. Inactivation of α2-antiplasmin was comparable to pharmacological r-tPA for dissolving thrombi. However, α2-antiplasmin inactivation showed a unique pattern of thrombus specificity, because unlike r-tPA, it did not degrade fibrinogen or enhance experimental bleeding. This suggests that modifying the activity of a key regulator of the fibrinolytic system, like α2-antiplasmin, may have unique therapeutic value in pulmonary embolism.

Contemporary Trends and Age-Specific Sex Differences in Management and Outcome for Patients With ST-Segment Elevation Myocardial Infarction

BACKGROUND

Age- and sex-specific differences exist in the treatment and outcome of ST-elevation myocardial infarction (STEMI). We sought to describe age- and sex-matched contemporary trends of in-hospital management and outcome of patients with STEMI.

METHODS AND RESULTS

We analyzed data from 5 Italian nationwide prospective registries, conducted between 2001 and 2014, including consecutive patients with STEMI. All the analyses were age- and sex-matched, considering 4 age classes: <55, 55 to 64, 65 to 74, and ≥75 years. A total of 13 235 patients were classified as having STEMI (72.1% men and 27.9% women). A progressive shift from thrombolysis to primary percutaneous coronary intervention occurred over time, with a concomitant increase in overall reperfusion rates (P for trend <0.0001), which was consistent across sex and age classes. The crude rates of in-hospital death were 3.2% in men and 8.4% in women (P<0.0001), with a significant increase over age classes for both sexes and a significant decrease over time for both sexes (all P for trend <0.01). On multivariable analysis, age (odds ratio 1.09, 95% CI 1.07-1.10, P<0.0001) and female sex (odds ratio 1.44, 95% CI 1.07-1.93, P=0.009) were found to be significantly associated with in-hospital mortality after adjustment for other risk factors, but no significant interaction between these 2 variables was observed (P for interaction=0.61).

CONCLUSIONS

Despite a nationwide shift from thrombolytic therapy to primary percutaneous coronary intervention for STEMI affecting both sexes and all ages, women continue to experience higher in-hospital mortality than men, irrespective of age.

Comparison of Immediate With Delayed Stenting Using the Minimalist Immediate Mechanical Intervention Approach in Acute ST-Segment-Elevation Myocardial Infarction: The MIMI Study

BACKGROUND

Delayed stent implantation after restoration of normal epicardial flow by a minimalist immediate mechanical intervention aims to decrease the rate of distal embolization and impaired myocardial reperfusion after percutaneous coronary intervention. We sought to confirm whether a delayed stenting (DS) approach (24-48 hours) improves myocardial reperfusion, versus immediate stenting, in patients with acute ST-segment-elevation myocardial infarction undergoing primary percutaneous coronary intervention.

METHODS AND RESULTS

In the prospective, randomized, open-label minimalist immediate mechanical intervention (MIMI) trial, patients (n=140) with ST-segment-elevation myocardial infarction ≤12 hours were randomized to immediate stenting (n=73) or DS (n=67) after Thrombolysis In Myocardial Infarction 3 flow restoration by thrombus aspiration. Patients in the DS group underwent a second coronary arteriography for stent implantation a median of 36 hours (interquartile range 29-46) after randomization. The primary end point was microvascular obstruction (% left ventricular mass) on cardiac magnetic resonance imaging performed 5 days (interquartile range 4-6) after the first procedure. There was a nonsignificant trend toward lower microvascular obstruction in the immediate stenting group compared with DS group (1.88% versus 3.96%; P=0.051), which became significant after adjustment for the area at risk (P=0.049). Median infarct weight, left ventricular ejection fraction, and infarct size did not differ between groups. No difference in 6-month outcomes was apparent for the rate of major cardiovascular and cerebral events.

CONCLUSIONS

The present findings do not support a strategy of DS versus immediate stenting in patients with ST-segment-elevation infarction undergoing primary percutaneous coronary intervention and even suggested a deleterious effect of DS on microvascular obstruction size.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01360242.

Efficacy and safety of ticagrelor versus clopidogrel with different dosage in high-risk patients with acute coronary syndrome

BACKGROUND

Dual antiplatelet therapy is recommended as a standard antiplatelet strategy in acute coronary syndrome. For those with reduced pharmacologic response to clopidogrel, strengthening antiplatelet therapy (clopidogrel 150mg daily) may reduce adverse clinical events. Ticagrelor is a direct-acting inhibitor of the adenosine diphosphate receptor P2Y12 that has a more rapid onset and offset than clopidogrel.

METHODS

In this retrospective study, we compared ticagrelor (180mg loading dose 90mg twice daily thereafter), clopidogrel (300mg loading dose, 75mg or 150mg daily thereafter) for the prevention of cardiovascular events in 273 high-risk patients admitted to coronary care unit with acute coronary syndrome.

RESULTS

The rate of IST in hospital was significantly reduced in patients of ticagrelor group comparing with those receiving clopidogrel 75mg (0.69% vs 8.2%, p=0.009). Moreover, the TVR rate was less in the ticagrelor group than clopidogrel 75mg group (2.7% vs 13.1%, p=0.007) 6months follow-up. The incidence of MACCE has no difference between the two clopidogrel groups. Kaplan-Meier analysis of MACCE-free indicated that there was no difference between the three groups. Ticagrelor significantly increased the rate of minor bleeding compared with clopidogrel 75mg daily during hospital (45.5% vs 26.2%,p=0.012) and 6-month follow-up (66.9% vs 45.9%,p=0.004).Bleeding-free prognosis was significantly better in the clopidogrel 75mg daily group.

CONCLUSIONS

In patients with acute coronary syndrome undergoing PCI, the rate of in-stent thrombosis and TVR were significantly reduced treated with ticagrelor compared with clopidogrel 75mg daily, without an increase of overall major bleeding, but with an increase of minor bleeding.

Coronary angiography after cardiac arrest: Rationale and design of the COACT trial

BACKGROUND

Ischemic heart disease is a major cause of out-of-hospital cardiac arrest. The role of immediate coronary angiography (CAG) and percutaneous coronary intervention (PCI) after restoration of spontaneous circulation following cardiac arrest in the absence of ST-segment elevation myocardial infarction (STEMI) remains debated.

HYPOTHESIS

We hypothesize that immediate CAG and PCI, if indicated, will improve 90-day survival in post-cardiac arrest patients without signs of STEMI.

DESIGN

In a prospective, multicenter, randomized controlled clinical trial, 552 post-cardiac arrest patients with restoration of spontaneous circulation and without signs of STEMI will be randomized in a 1:1 fashion to immediate CAG and PCI (within 2 hours) versus initial deferral with CAG and PCI after neurological recovery. The primary end point of the study is 90-day survival. The secondary end points will include 90-day survival with good cerebral performance or minor/moderate disability, myocardial injury, duration of inotropic support, occurrence of acute kidney injury, need for renal replacement therapy, time to targeted temperature control, neurological status at intensive care unit discharge, markers of shock, recurrence of ventricular tachycardia, duration of mechanical ventilation, and reasons for discontinuation of treatment.

SUMMARY

The COACT trial is a multicenter, randomized, controlled clinical study that will evaluate the effect of an immediate invasive coronary strategy in post-cardiac arrest patients without STEMI on 90-day survival.

α2-Antiplasmin: New Insights and Opportunities for Ischemic Stroke

Thrombotic vascular occlusion is the leading cause of ischemic stroke. High blood levels of α₂-antiplasmin (a2AP), an ultrafast, covalent inhibitor of plasmin, have been linked in humans to increased risk of ischemic stroke and failure of tissue plasminogen activator (tPA) therapy. Consistent with these observations, a2AP neutralizes the therapeutic benefit of tPA therapy in experimental stroke. In addition, a2AP has deleterious, dose-related effects on ischemic brain injury in the absence of therapy. Experimental therapeutic inactivation of a2AP markedly reduces microvascular thrombosis, ischemic brain injury, brain swelling, brain hemorrhage, and death after thromboembolic stroke. These data provide new insights into the critical importance of a2AP in the pathogenesis of ischemic brain injury and suggest that transiently inactivating a2AP may have therapeutic value in ischemic stroke.

Comparison of Safety and Effectiveness Between Right Versus Left Radial Arterial Access in Primary Percutaneous Coronary Intervention for Acute ST Segment Elevation Myocardial Infarction

BACKGROUND

Transradial approach (TRA) is now considered the standard of care in many centres for elective and primary percutaneous intervention (PCI). The use of the radial approach in ST segment elevation myocardial infarction (STEMI) patients has been associated with a significant reduction in major adverse cardiac events. However, it is still unclear if the side of radial access (right vs. left) has impact on safety and effectiveness of TRA in primary PCI. So this study was conducted to compare the safety, feasibility, and outcomes of right radial access (RRA) vs. left radial access (LRA) in the setting of primary PCI.

METHODS

We retrospectively analysed the data of 400 consecutive patients presenting to our institution with STEMI for whom primary PCIs were performed via RRA and LRA.

RESULTS

Mean age of the whole studied population was 57±12.8 years, with male predominance (77.2%). There were 202 cases in the RRA group and 198 in the LRA group, with no significant difference in demographics and clinical characteristics for patients included in both groups. There was no significant difference in procedure success rate (97.5% for RRA vs. 98.4% for LRA; P=0.77). In addition, no significant difference between both approaches was observed in the contrast volume, number of catheters, fluoroscopy time (FT), needle-to-balloon time, post-procedure vascular complications, in hospital reinfarction, stroke/transient ischaemic attack (TIA) or death.

CONCLUSION

Right radial access and LRA are equally safe and effective in the setting of primary PCI. Both approaches have a high success rate and comparable needle-to-balloon time.

Analytic Reviews : Potential New Therapies for Acute Ischemic Stroke

Evidence from animal models of acute stroke suggests ischemia may be reversible if blood flow is restored in the first few hours. Studies of human stroke using posi tron emission tomography demonstrate areas with re duced blood flow and relatively preserved metabolism, indicating potentially reversible ischemic brain. Resto ration of blood flow during this reversible phase should improve outcome after stroke.

Many therapeutic strategies for treatment of acute ischemic stroke have been proposed, including increas ing collateral flow, removing vascular obstructions, and interfering with the intracellular cascade of events that lead to neuronal cell death. Hypervolemic hemodilution reduces viscosity and increases cerebral blood flow, and this may hopefully raise blood flow above the critical threshold of irreversible ischemia. Naloxone, calcium channel blockers, and glutamate antagonists alter blood flow and influence intracellular events during and after acute ischemia. Thrombolytic therapy restores blood flow by lysis of obstructing clot. These therapies show promise in preliminary studies, but additional ran domized controlled studies are needed.

Concept and Clinical Application of Platelet Glycoprotein IIb/IIIa Inhibition with Abciximab (c7E3 Fab; ReoPro) for the Prevention of Acute Ischemic Syndromes

The platelet membrane glycoprotein (GP) IIb/IIIa integrin receptor is the final common pathway leading to platelet aggregation. Local aggregation commonly occurs following atherosclerotic plaque rupture or other injury to the vascular wall. When GP IIb/IIIa is activated, fibrinogen and von Willebrand factor bind to the receptor with high affinity, crosslinking platelets and locking them to the vessel surface and to each other. This process is central to arterial thrombus formation and consequent acute coronary syndromes, such as myocardial infarction (MI), unstable angina, and abrupt closure following revascularization procedures. Abciximab (c7E3 Fab; ReoPro) is a chimeric monoclonal antibody fragment developed specifically to inhibit GP IIb/IIIa receptor activity and thus prevent platelet aggregation and thrombosis. Abciximab has been evaluated in several clinical studies, the largest of which was the Evaluation of Abciximab for the Prevention of Ischemic Complications (EPIC) trial. This randomized, multicenter, placebo-controlled trial enrolled 2,099 patients at high risk for ischemic complications following coronary revascularization. The patients were randomized into three treatment groups: placebo, abciximab bolus (0.25 mg/kg), or abciximab bolus plus 12-h infusion (10 μg/min). Patients in the abciximab bolus plus infusion group had significant reductions, compared with placebo, in a composite end point of death, nonfatal MI, and urgent coronary intervention within 30 days. These positive, short-term findings were maintained at 6 months of follow-up. Bleeding complications and transfusions were significantly increased in abciximab patients, although there was no increase in bleeding-related death, stroke, or surgery. Retrospective secondary analyses suggested that many of the bleeding events observed in the EPIC trial may have been associated with concomitant high-dose heparin therapy, particularly in lighter weight patients. Subsequent clinical trials have shown that bleeding events can be reduced in patients treated with abciximab by using weight-adjusted heparin dosing without affecting the efficacy of the abciximab bolus plus infusion regimen. Examination of health economic data from the EPIC trial showed that abciximab bolus plus infusion is cost effective as well as clinically beneficial. These results confirm the importance of platelet GP IIb/IIIa receptor blockade in the treatment of acute thrombotic syndromes. Key Words: Platelet aggregation—GP IIb/IIIa receptor—Coronary revascularization— Ischemia.

A Prospective, Nonrandomized, Open-Labeled Pilot Study Investigating the Use of Magnesium in Patients Undergoing Nonacute Percutaneous Coronary Intervention with Stent Implantation

Background: Magnesium has recently been shown to inhibit acute stent thrombosis in animal models. This study tested the feasibility of magnesium administration in patients undergoing nonacute percutaneous coronary intervention with stent implantation.

Methods: Twenty-one patients undergoing nonemergent percutaneous coronary intervention were enrolled and received intravenous magnesium sulfate (2-g bolus over 20 minutes prepercutaneous coronary intervention, followed by 14 g over 12 hours infusion). Endpoints: safety outcomes-hypotension, bradycardia, bleeding complications and heart block within first 24 hours; angiographic outcomes-acute thrombotic occlusion and need for platelet glycoprotein Ilb/Illa inhibitor bailout; and clinical outcomes-death, myocardial infarction, recurrent ischemia, and need for urgent revascularization at 48 hours and 30 days.

Results: No significant effects on heart rate or blood pressure, major bleeding complication, or new electrocardiographic changes were observed. Angiographic thrombus was visualized in two cases, and coronary artery dissection in one case poststent deployment. None of these cases required the use of glycoprotein inhibitors for bailout. Death, myocardial infarction, recurrent ischemia, and need for urgent revascularization were not observed. The serum magnesium level increased from 2.1 ± 0.3 mg/dL at baseline to 3.5 ± 0.8 mg/dL at the end of the infusion (P < .0001). Platelet activation was significantly inhibited at the end of the magnesium sulfate infusion.

Conclusion: Intravenous magnesium sulfate has been demonstrated as a feasible and safe agent in patients undergoing nonacute percutaneous coronary intervention with stent implantation. A randomized clinical trial comparing magnesium with glycoprotein inhibitors during percutaneous coronary intervention is warranted.

Potential Benefits from Heating the High-Dose rtPA Boluses Used in Catheter-Directed Thrombolysis for Acute/Subacute Lower Limb Ischemia

Purpose:

To explore the potential benefits from heating recombinant tissue plasminogen activator (rtPA) before catheter-directed thrombolysis in patients with lower-limb ischemia of <30 days' duration.

Methods:

Over a 2-year period, 34 patients (26 men; mean age 63.5 years, range 39–80) with 10 iliac and 24 infrainguinal arterial occlusions (5 embolic and 29 thrombotic) were treated with two 5-mg boluses of rtPA injected into the proximal clot, followed by 2 additional 5-mg boluses of rtPA. In the first 18 patients (group A), room temperature rtPA was administered, whereas in the last 16 patients (group B), the rtPA boluses were heated to 38°C for 30 minutes before injection. Residual thrombus was treated with a continuous infusion of 2.5 mg/h of rtPA for 4 hours then at a reduced dose (1 mg/h).

Results:

Successful thrombolysis was achieved in 28 (82%) arteries. Unmasked lesions were treated with balloon angioplasty/stenting in 17 cases and with surgery in 4. One fatal retroperitoneal hematoma occurred in group A. Heating the rtPA did not significantly alter the outcome of thrombolysis. However, a statistically significant reduction in the total rtPA dose was observed in group B (24.28 mg versus 27.9 mg in group A, p = 0.05), as well as quicker lysis (2 hours, 42 minutes versus 6 hours, 12 minutes in group A, p = 0.001). There was no statistical difference in the amputation-free survival at 30 days between the groups.

Conclusions:

In patients with acute or subacute lower limb ischemia treated with catheter-directed thrombolysis, heating the rtPA results in faster lysis with a considerable reduction in the total dose of the lytic agent.

Thrombolytic Therapy: A Comprehensive Review of its Use in Clinical Medicine—Part I

In the first part of this comprehensive review of thrombolytic therapy in clinical medicine, we begin with a brief history of fibrinolysis, followed by a review of the components of die endogenous fibrinolytic system and the currently available plasminogen activators. An in-depth examination of thrombolysis in treatment of acute myocardial infarction follows, Including recommendations for management based on available clinical trial data. New developments in thrombolytic therapy are also discussed.

Impact of Contrast-Induced Acute Kidney Injury After Percutaneous Coronary Intervention on Short- and Long-Term Outcomes: Pooled Analysis From the HORIZONS-AMI and ACUITY Trials

BACKGROUND

Contrast-induced acute kidney injury (CI-AKI), defined as a serum creatinine increase ≥0.5 mg/dL or ≥25% within 72 hours after contrast exposure, is a common complication of procedures requiring contrast media and is associated with increased short- and long-term morbidity and mortality. Few studies describe the effects of CI-AKI in a large-scale acute coronary syndrome population, and the relationship between CI-AKI and bleeding events has not been extensively explored. We sought to evaluate the impact of CI-AKI after percutaneous coronary intervention in patients presenting with acute coronary syndrome.

METHODS AND RESULTS

We pooled patient-level data for 9512 patients from the percutaneous coronary intervention cohorts of the Harmonizing Outcomes With Revascularization and Stents in Acute Myocardial Infarction (HORIZONS-AMI) and Acute Catheterization and Urgent Intervention Triage Strategy (ACUITY) multicenter randomized trials. Patients were classified according to CI-AKI development, and cardiovascular outcomes at 30 days and 1 year were compared between groups. A total of 1212 patients (12.7%) developed CI-AKI. Patients with CI-AKI were older, with a more extensive comorbidity profile than without CI-AKI. Multivariable analysis confirmed several previously identified predictors of CI-AKI, including diabetes mellitus, contrast volume, age, and baseline hemoglobin. Mortality rates were significantly higher in the CI-AKI group at 30 days (4.9% versus 0.7%; P<0.0001) and 1 year (9.8% versus 2.9%; P<0.0001), as were rates of 1-year myocardial infarction, definite/probable stent thrombosis, target lesion revascularization, and major adverse cardiac events. Major bleeding (13.8% versus 5.4%; hazard ratio, 2.64; 95% confidence interval, 2.21-3.15; P<0.0001) was also higher in patients with CI-AKI. After multivariable adjustment, results were unchanged.

CONCLUSIONS

CI-AKI after percutaneous coronary intervention in patients presenting with acute coronary syndrome is independently associated with increased risk of short- and long-term ischemic and hemorrhagic events.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifiers: NCT00433966 (HORIZONS-AMI) and ACUITY (NCT00093158).

PEGylation of Truncated Streptokinase Leads to Formulation of a Useful Drug with Ameliorated Attributes

Streptokinase (SK) remains a favored thrombolytic agent in the developing world as compared to the nearly 10-fold more expensive human tissue-plasminogen activator (tPA) for the dissolution of pathological fibrin clots in myocardial infarction. However, unlike the latter, SK induces systemic activation of plasmin which results in a greater risk of hemorrhage. Being of bacterial origin, it elicits generation of unwanted antibody and has a relatively short half-life in vivo that needs to be addressed to make it more efficacious clinically. In order to address these lacunae, in the present study we have incorporated cysteine residues specifically at the N- and C-termini of partially truncated SK and these were then PEGylated successfully. Some of the obtained derivatives displayed enhanced plasmin resistance, longer half-life (upto several hours), improved fibrin clot-specificity and reduced immune-reactivity as compared to the native SK (nSK). This paves the way for devising next-generation SK-based thrombolytic agent/s that besides being fibrin clot-specific are endowed with an improved efficacy by virtue of an extended in vivo half-life.

Effect of Serum Fibrinogen, Total Stent Length, and Type of Acute Coronary Syndrome on 6-Month Major Adverse Cardiovascular Events and Bleeding After Percutaneous Coronary Intervention

This study evaluated the relation between baseline fibrinogen and 6-month major adverse cardiovascular events (MACE) and bleeding after percutaneous coronary intervention (PCI). Three hundred eighty-seven subjects (65.6 ± 16.1 years, 69.5% men, 26.9% acute coronary syndrome [ACS]) who underwent PCI with baseline fibrinogen and platelet reactivity (VerifyNow P2Y12 assay, Accumetrics, San Diego, California) measured were enrolled. Fibrinogen (368.8 ± 144.1 vs 316.8 ± 114.3 mg/dl; p = 0.001), total stent length (TSL; 44.5 ± 25.0 vs 32.2 ± 20.1 mm; p <0.001), and ACS presentation (40.6% vs 23.9%; p = 0.005) were independently associated with 6-month MACE rates (17.8%: myocardial infarction 9.8%, rehospitalization for ACS 3.6%, urgent revascularization 3.6%, stroke 0.5%, and death 0.3%). Measures of platelet reactivity were not associated with 6-month MACE. After multivariate analysis, fibrinogen ≥280 mg/dl (odds ratio [OR] 2.60, 95% CI 1.33 to 5.11, p = 0.005), TSL ≥32 mm (OR 3.21, 95% CI 1.82 to 5.64, p <0.001), and ACS presentation (OR 2.58, 95% CI 1.45 to 4.61, p = 0.001) were associated with higher 6-month MACE. In 271 subjects receiving chronic P2Y12 inhibitor therapy, 6-month Thrombolysis In Myocardial Infarction bleeding after PCI was 7.0%, but no difference in fibrinogen level (338.3 ± 109.7 vs 324.3 ± 113.8 mg/dl, p = 0.60) stratified by Thrombolysis In Myocardial Infarction bleeding was observed. In conclusion, elevated serum fibrinogen, ACS presentation, and longer TSL are independently associated with higher 6-month MACE after PCI, whereas no association with on-thienopyridine platelet reactivity and 6-month MACE was observed. Post-PCI bleeding was not associated with lower fibrinogen level.

The Effect of High Dose Cilostazol and Rosuvastatin on Periprocedural Myocardial Injury in Patients with Elective Percutaneous Coronary Intervention

BACKGROUND

The aim of our study was to assess the effect of pretreatment with cilostazol and rosuvastatin combination before elective percutaneous coronary intervention (PCI) on peri-procedural myocardial injury (PPMIJ).

METHODS

We randomly assigned 172 patients with stable angina pectoris scheduled for elective PCI to pre- treatment with Cilostazol 200mg and Rosuvastatin 40 mg (group 1), or to pretreatment with Rosuvastatin 40 mg group (group 2). The primary end-point was the occurrence of PPMIJ defined as any cardiac troponin I (Tn I) level elevated above the upper normal limit (UNL). The occurrence of peri-procedural myocardial infarction (PPMIN) was defined as a post-procedural increase in cTnI level ≥ 5 times above the UNL.

RESULTS

There was no significant difference in baseline characteristics between group 1 (n = 86) and group 2 (n = 86). The rate of PPMIJ (21% vs. 24%, p = 0.58) and PPMIN (2.3% vs. 7%, p = 0.27) were similar between the two study groups. Subgroup analysis performed on those patients without statin therapy before PCI (53 patients in group 1 and 50 patients in group 2) showed that the incidence of PPMIJ was significantly lower in the group 1 patients without chronic statin treatment [17% (9/53) versus 34% (17/50); p = 0.04], but the rate of PPMIN was similar between the two groups for those patients without chronic statin treatment [1.9% (1/53) versus 10% (5/50); p = 0.07].

CONCLUSIONS

We found that adjunct cilostazol and rosuvastatin pre-treatment did not significantly reduce PPMIJ after elective PCI in patients with stable angina pectoris. However, adjunct cilostazol pre-treatment could reduce PPMIJ in patients without chronic statin therapy before elective PCI.

KEY WORDS

Cilostazol; Myocardial injury; Percutaneous coronary intervention; Statin.

CYP2C19*2 and Other Allelic Variants Affecting Platelet Response to Clopidogrel Tested by Thrombelastography in Patients with Acute Coronary Syndrome

Background:

To investigate the contributions of CYP2C19 polymorphisms to the various clopidogrel responses tested by thrombelastography (TEG) in Chinese patients with the acute coronary syndrome (ACS).

Methods:

Patients were screened prospectively with ACS diagnose and were treated with clopidogrel and aspirin dual antiplatelet therapy. CYP2C19 loss of function (LOF) and gain of function (GOF) genotype, adenosine 5′-diphosphate (ADP)-channel platelet inhibition rate (PIR) tested by TEG and the occurrence of 3-month major adverse cardiovascular events and ischemic events were assessed in 116 patients.

Results:

High on-treatment platelet reactivity (HTPR) prevalence defined by PIR <30% by TEG in ADP-channel was 32.76% (38/116). With respect to the normal wild type, CYP2C19*2, and *3 LOF alleles, and *17 GOF alleles, patients were classified into three metabolism phenotypes: 41.38% were extensive metabolizers (EMs), 56.90% were intermediate metabolizers (IMs), and 1.72% were poor metabolizers (PMs). Of the enrolled patients, 31.47%, 5.17%, and 0.43%, respectively, were carriers of *2, *3, and *17 alleles. The HTPR incidence differed significantly according to CYP2C19 genotypes, accounting for 18.75%, 41.54%, and 100.00% in EMs, IMs, and PMs, respectively. Eighteen (17.24%) ischemic events occurred during the 3-month follow-up, and there was a significant difference in ischemic events between HTPR group and nonhigh on-treatment platelet reactivity group.

Conclusions:

Genetic CYP2C19 polymorphisms are relative to the inferior, the antiplatelet activity after clopidogrel admission and may increase the incidence of ischemic events in patients with ACS.

Efficacy and safety of fondaparinux versus enoxaparin in patients undergoing percutaneous coronary intervention treated with the glycoprotein IIb/IIIa inhibitor tirofiban

BACKGROUND

In worldwide, the mortality rate of acute myocardial infarction (AMI) raises year by year. Although the applications of percutaneous coronary intervention (PCI) and anticoagulants effectively reduce the mortality of patients with acute coronary syndrome (ACS), but also increase the incidence of bleeding. Therefore, drugs with stable anticoagulant effects are urgently required.

METHODS

We enrolled 894 patients with acute coronary syndrome who underwent percutaneous coronary intervention in Shenyang Northern Hospital from February 2010 to May 2012; 430 patients were included in the fondaparinux group (2.5 mg/d), and 464 were included in the enoxaparin group (1 mg/kg twice daily). Fondaparinux and enoxaparin were applied for 3-7 days. All patients were treated with tirofiban (10 μg/kg for 3 min initially and 0.15 μg/(kg · min) for 1 to 3 days thereafter). The primary efficacy endpoint was the incidence of a major adverse cerebrovascular or cardiovascular event. The primary safety endpoint was bleeding within 30 days and 1 year after percutaneous coronary intervention.

RESULTS

One-year data were available for 422 patients in the fondaparinux group and for 453 in the enoxaparin group. The incidence of a major adverse cerebrovascular or cardiovascular event (10.9 % vs 12.6 %, P = 0.433) and cardiac mortality (0.5 % vs 1.5 %, P = 0.116) were generally lower in the fondaparinux group than in the enoxaparin group, although the differences were not significant. Compared with the enoxaparin group, the fondaparinux group had a significantly decreased rate of bleeding at 30 days (0.9 % vs 2.8 %) and 1 year (2.4 % vs 5.4 %). In addition, the rate of major bleeding events was lower in the fondaparinux group, but this difference was not significant (0.2 % vs 0.9 %, 0.2 % vs 1.1 %).

CONCLUSIONS

In tirofiban-treated patients with acute coronary syndrome undergoing percutaneous coronary intervention, fondaparinux presented similar efficacy for ischemia events as enoxaparin. However, fondaparinux significantly decreased the incidence of bleeding, thus providing safer anticoagulation therapy.

A Study of Platelet Inhibition, Using a 'Point of Care' Platelet Function Test, following Primary Percutaneous Coronary Intervention for ST-Elevation Myocardial Infarction [PINPOINT-PPCI]

BACKGROUND

Rapid coronary recanalization following ST-elevation myocardial infarction (STEMI) requires effective anti-platelet and anti-thrombotic therapies. This study tested the impact of door to end of procedure ('door-to-end') time and baseline platelet activity on platelet inhibition within 24hours post-STEMI.

METHODS AND FINDINGS

108 patients, treated with prasugrel and procedural bivalirudin, underwent Multiplate® platelet function testing at baseline, 0, 1, 2 and 24hours post-procedure. Major adverse cardiac events (MACE), bleeding and stent thrombosis (ST) were recorded. Baseline ADP activity was high (88.3U [71.8-109.0]), procedural time and consequently bivalirudin infusion duration were short (median door-to-end time 55minutes [40-70] and infusion duration 30minutes [20-42]). Baseline ADP was observed to influence all subsequent measurements of ADP activity, whereas door-to-end time only influenced ADP immediately post-procedure. High residual platelet reactivity (HRPR ADP>46.8U) was observed in 75% of patients immediately post-procedure and persisted in 24% of patients at 2hours. Five patients suffered in-hospital MACE (4.6%). Acute ST occurred in 4 patients, all were <120mins post-procedure and had HRPR. No significant bleeding was observed. In a post-hoc analysis, pre-procedural morphine use was associated with significantly higher ADP activity following intervention.

CONCLUSIONS

Baseline platelet function, time to STEMI treatment and opiate use all significantly influence immediate post-procedural platelet activity.