Effects of complete revascularization according to age in patients with ST-segment elevation myocardial infarction and multivessel disease (COMPLETE-AGE).

BACKGROUND: In ST-segment elevation myocardial infarction (STEMI), complete revascularization with percutaneous coronary intervention (PCI) reduces major cardiovascular events compared with culprit-lesion-only PCI. Whether age influences these results remains unknown. METHODS: COMPLETE was a multinational, randomized trial evaluating a strategy of staged complete revascularization, consisting of angiography-guided PCI of all suitable nonculprit lesions, versus a strategy of culprit-lesion-only PCI. In this prespecified subgroup analysis, treatment effect according to age (≥65 years vs <65 years) was determined for the first coprimary outcome of cardiovascular (CV) death or new myocardial infarction (MI) and the second coprimary outcome of CV death, new MI, or ischemia-driven revascularization (IDR). Median follow-up was 35.8 months (interquartile range [IQR]: 27.6-44.3 months). RESULTS: Of 4,041 patients randomized in COMPLETE, 1,613 were aged ≥ 65 years (39.9%). Higher event rates were observed for both coprimary outcomes in patients aged ≥ 65 years comparted with those aged < 65 years (11.2% vs 7.9%, HR 1.49, 95% CI 1.22-1.83; 14.4% vs 11.8%, HR 1.28, 95% CI 1.07-1.52, respectively). Complete revascularization reduced the first coprimary outcome in patients ≥ 65 years (9.7% vs 12.5%, HR 0.77; 95% CI, 0.58-1.04) and < 65 years (6.7% vs 9.1%, HR 0.72; 95% CI, 0.54-0.96)(interaction P = .74). The second coprimary outcome was reduced in those ≥ 65 years (HR 0.56, 95% CI, 0.43-0.74) and < 65 years (HR 0.48, 95% CI, 0.37-0.61 (interaction P = .37). A sensitivity analysis was performed with consistent results demonstrated using a 75-year threshold (albeit attenuated). CONCLUSIONS: In patients with STEMI and multivessel CAD, complete revascularization compared with culprit-lesion-only PCI reduced major cardiovascular events regardless of patient age and could be considered as a revascularization strategy in older adults.

Complete Revascularization with Multivessel PCI for Myocardial Infarction.

BACKGROUND: In patients with ST-segment elevation myocardial infarction (STEMI), percutaneous coronary intervention (PCI) of the culprit lesion reduces the risk of cardiovascular death or myocardial infarction. Whether PCI of nonculprit lesions further reduces the risk of such events is unclear. METHODS: We randomly assigned patients with STEMI and multivessel coronary artery disease who had undergone successful culprit-lesion PCI to a strategy of either complete revascularization with PCI of angiographically significant nonculprit lesions or no further revascularization. Randomization was stratified according to the intended timing of nonculprit-lesion PCI (either during or after the index hospitalization). The first coprimary outcome was the composite of cardiovascular death or myocardial infarction; the second coprimary outcome was the composite of cardiovascular death, myocardial infarction, or ischemia-driven revascularization. RESULTS: At a median follow-up of 3 years, the first coprimary outcome had occurred in 158 of the 2016 patients (7.8%) in the complete-revascularization group as compared with 213 of the 2025 patients (10.5%) in the culprit-lesion-only PCI group (hazard ratio, 0.74; 95% confidence interval [CI], 0.60 to 0.91; P = 0.004). The second coprimary outcome had occurred in 179 patients (8.9%) in the complete-revascularization group as compared with 339 patients (16.7%) in the culprit-lesion-only PCI group (hazard ratio, 0.51; 95% CI, 0.43 to 0.61; P<0.001). For both coprimary outcomes, the benefit of complete revascularization was consistently observed regardless of the intended timing of nonculprit-lesion PCI (P = 0.62 and P = 0.27 for interaction for the first and second coprimary outcomes, respectively). CONCLUSIONS: Among patients with STEMI and multivessel coronary artery disease, complete revascularization was superior to culprit-lesion-only PCI in reducing the risk of cardiovascular death or myocardial infarction, as well as the risk of cardiovascular death, myocardial infarction, or ischemia-driven revascularization. (Funded by the Canadian Institutes of Health Research and others; COMPLETE ClinicalTrials.gov number, NCT01740479.).

Morphine and clinical outcomes in patients with ST segment elevation myocardial infarction treated with fibrinolytic and antiplatelet therapy: Insights from the TREAT trial.

BACKGROUND: Morphine is commonly used to relieve pain, anxiety and dyspnea in STEMI but it lowers blood pressure and delays the activity of oral antiplatelet agents. The impact of morphine on clinical outcomes remains unknown. This analysis was performed to determine if morphine use was associated with increased risk of adverse clinical events among STEMI patients treated with fibrinolytic therapy and clopidogrel or ticagrelor. METHODS: In the Ticagrelor in Patients with ST Elevation Myocardial Infarction Treated with Pharmacological Thrombolysis (TREAT) study, 3799 STEMI patients treated with fibrinolysis were randomized to receive clopidogrel or ticagrelor. Morphine use was left to the discretion of the treating physicians. In this pre-specified analysis, we evaluated clinical outcomes based on the use and timing of morphine administration. Outcomes were stratified by randomized treatment group. Multivariable analysis was performed using Inverse Probability Treatment Weighting (IPTW) weighting. RESULTS: Morphine was used in 53% of patients. After adjustment using IPTW weighting, morphine use was associated with higher hazard of reinfarction at 7 days (HR 4.9, P = .0006) and 30 days (HR 1.7, P = .04), and lower hazard of major bleeding (HR 0.37, P = .006). There was no significant difference in mortality at any time point. CONCLUSIONS: Among patients with STEMI treated with fibrinolytic therapy, morphine use was associated with a higher risk of early reinfarction and a lower risk of major bleeding but no difference in mortality. CLINICAL TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT02298088.

Use and outcomes of dual antiplatelet therapy for acute coronary syndrome in patients with chronic kidney disease: insights from the Canadian Observational Antiplatelet Study (COAPT).

Chronic kidney disease (CKD) increases the risk of adverse outcomes in acute coronary syndrome (ACS). The optimal regimen of dual antiplatelet therapy (DAPT) post-percutaneous coronary intervention (PCI) in CKD poses a challenge due to the increased bleeding and clotting tendencies, particularly since patients with CKD were underrepresented in randomized controlled trials. We examined the practice patterns of DAPT prescription stratified by the presence of CKD. The multicentre prospective Canadian Observational Antiplatelet Study (COAPT) enrolled patients with ACS between December 2011 and May 2013. The present study is a subgroup analysis comparing type and duration of DAPT and associated outcomes among patients with and without CKD (eGFR < 60 ml/min/1.73 m2, calculated by CKD-EPI). Patients with CKD (275/1921, 14.3%) were prescribed prasugrel/ticagrelor less (18.5% vs 25.8%, p = 0.01) and had a shorter duration of DAPT therapy versus patients without CKD (median 382 vs 402 days, p = 0.003). CKD was associated with major adverse cardiovascular events (MACE) at 12 months (p < 0.001) but not bleeding when compared to patients without CKD. CKD was associated with MACE in both patients on prasugrel/ticagrelor (p = 0.017) and those on clopidogrel (p < 0.001) (p for heterogeneity = 0.70). CKD was associated with increased bleeding only among patients receiving prasugrel/ticagrelor (p = 0.007), but not among those receiving clopidogrel (p = 0.64) (p for heterogeneity = 0.036). Patients with CKD had a shorter DAPT duration and were less frequently prescribed potent P2Y12 inhibitors than patients without CKD. Overall, compared with patients without CKD, patients with CKD had higher rates of MACE and similar bleeding rates. However, among those prescribed more potent P2Y12 inhibitors, CKD was associated with more bleeding than those without CKD. Further studies are needed to better define the benefit/risk evaluation, and establish a more tailored and evidence-based DAPT regimen for this high-risk patient group.

Invasive Assessment of Microvascular Resistance in Hypertrophic Cardiomyopathy With Echocardiographic Correlates.

INTRODUCTION: Hypertrophic cardiomyopathy (HCM) is often associated with ischaemia despite lack of focal epicardial coronary stenosis. Our aim was to assess invasive coronary microvascular circulation and correlate findings with echocardiography. METHODS: We prospectively enrolled patients with HCM and controls who were referred for diagnostic coronary angiography. A pressure-temperature sensor coronary guidewire was used with intracoronary injections of room-temperature saline to measure mean coronary transit time during rest and hyperaemia induced with intravenous adenosine. The index of microvascular resistance (IMR) was calculated. Left ventricular mass was calculated during echocardiographic studies. RESULTS: Patients with HCM (n=12) and controls (n=7), had similar demographics. Left ventricular ejection fraction was higher in HCM (76.7%±11.0% vs 55.0%±15.9%, p=0.003). IMR was non-significantly higher in HCM (21.7±10.2 vs 15.3±4.8, p=0.16). Only patients with HCM had abnormal IMR (>25). Coronary flow reserve was non-significantly higher in HCM (2.7±1.6 vs 2.1±1.2, p=0.34). IMR correlated with left ventricular mass in hypertrophic cardiomyopathy subjects (Pearson r=0.68, p=0.02). CONCLUSIONS: Microvascular dysfunction as assessed by IMR may be abnormal in HCM and is correlated with left ventricular mass.

Upstream anticoagulation for patients with ST-elevation myocardial infarction undergoing primary percutaneous coronary intervention: Insights from the TOTAL trial.

OBJECTIVES: To assess the relationship between preprocedural anticoagulation use and clinical and angiographic outcomes. BACKGROUND: For patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI), the optimal timing of anticoagulant administration remains uncertain. METHODS: Patients enrolled in the TOTAL trial were stratified based on whether or not they had received any parenteral anticoagulant prior to randomization and PCI. Baseline and procedural characteristics were compared. For one-year clinical outcomes, Cox proportional modeling adjusted on a propensity score was used to analyze differences between groups. Angiographic endpoints were analyzed by logistic regression models adjusted for propensity scores. RESULTS: In the trial, 10,064 patients were enrolled and underwent PCI. Preprocedural anticoagulation was used in 6,381 patients (63%).The most common anticoagulant was intravenous unfractionated heparin (5,188, 81%). Patients who received preprocedural anticoagulation had higher rates of TIMI-2-3 or TIMI-3 flow and lower grades of thrombus prior to PCI. Pretreatment with anticoagulation was associated with lower use of bailout thrombectomy, GP IIb/IIIa inhibitors, and intra-aortic balloon pump. After adjustment, preprocedural anticoagulation was associated with lower rates of CABG and minor bleeding at 1 year but there were no significant differences in death, stroke, recurrent MI, cardiogenic shock, or congestive heart failure. CONCLUSIONS: Preprocedural anticoagulation is associated with improved flow and reduced thrombus in the IRA prior to PCI, less bailout thrombectomy during PCI but no difference in death, recurrent infarction, or heart failure at 1 year.

Canadian spontaneous coronary artery dissection cohort study: in-hospital and 30-day outcomes.

AIMS: Spontaneous coronary artery dissection (SCAD) was underdiagnosed and poorly understood for decades. It is increasingly recognized as an important cause of myocardial infarction (MI) in women. We aimed to assess the natural history of SCAD, which has not been adequately explored. METHODS AND RESULTS: We performed a multicentre, prospective, observational study of patients with non-atherosclerotic SCAD presenting acutely from 22 centres in North America. Institutional ethics approval and patient consents were obtained. We recorded baseline demographics, in-hospital characteristics, precipitating/predisposing conditions, angiographic features (assessed by core laboratory), in-hospital major adverse events (MAE), and 30-day major adverse cardiovascular events (MACE). We prospectively enrolled 750 SCAD patients from June 2014 to June 2018. Mean age was 51.8 ± 10.2 years, 88.5% were women (55.0% postmenopausal), 87.7% were Caucasian, and 33.9% had no cardiac risk factors. Emotional stress was reported in 50.3%, and physical stress in 28.9% (9.8% lifting >50 pounds). Predisposing conditions included fibromuscular dysplasia 31.1% (45.2% had no/incomplete screening), systemic inflammatory diseases 4.7%, peripartum 4.5%, and connective tissue disorders 3.6%. Most were treated conservatively (84.3%), but 14.1% underwent percutaneous coronary intervention and 0.7% coronary artery bypass surgery. In-hospital composite MAE was 8.8%; peripartum SCAD patients had higher in-hospital MAE (20.6% vs. 8.2%, P = 0.023). Overall 30-day MACE was 8.8%. Peripartum SCAD and connective tissue disease were independent predictors of 30-day MACE. CONCLUSION: Spontaneous coronary artery dissection predominantly affects women and presents with MI. Despite majority of patients being treated conservatively, survival was good. However, significant cardiovascular complications occurred within 30 days. Long-term follow-up and further investigations on management are warranted.

Radial versus femoral approach for saphenous vein grafts angiography and interventions.

BACKGROUND: Coronary angiography and intervention to saphenous venous grafts (SVGs) remain challenging. This study aimed to investigate the feasibility and safety of the radial approach compared to femoral access in a large cohort of patients undergoing SVG angiography and intervention. METHODS: Data from 1,481 patients from Canada, United States, and Spain who underwent procedures between 2010 and 2016 were collected. Patients must have undergone SVG coronary angiography and/or intervention. Demographics, procedural data, and in-hospital complications were recorded. RESULTS: Procedures were undertaken by either the radial (n = 863, 211 intervention) or femoral (n = 618, 260 intervention) approach. The mean number of SVGs per patient was similar between groups (radial 2.3 ± 0.7 vs femoral 2.6 ± 1.1, P = .61), but the radial group required a fewer number of catheters (2.6 ± 1.7 vs 4.1 ± 1.1, P < .001). Fluoroscopy time was comparable between groups, and there was a trend toward lower contrast volume in the radial group (P = .045). Overall, the total dose of heparin was significantly higher in the radial group (P < .001); however, radial patients experienced significantly less access-site bleeding complications (P < .001). Outpatients undergoing radial SVG interventions had a higher likelihood of a same-day discharge home (P < .001). CONCLUSIONS: Radial access for SVG angiography and intervention is safe and feasible, without increasing fluoroscopy time. In experienced centers, radial access was associated with fewer catheters used, lower contrast volume, and lower rate of vascular access-site bleeding complications. Moreover, outpatients undergoing SVG percutaneous coronary intervention though the radial approach had a higher likelihood of a same-day discharge home.

Is Fractional Flow Reserve Useful in Assessing Coronary Artery Fistula: A Case-Based Discussion and Review.

We present two cases where fractional flow reserve (FFR) was utilised to guide management of coronary artery fistula (CAF), an approach advocated in recent case studies. CAF is a coronary anomaly that may present with a variety of syndromes though is frequently asymptomatic. When to exclude the fistula (surgically or percutaneously) is not always clear. A way to quantify if the fistula is physiologically meaningful would be advantageous. Our findings suggest FFR may only be assessing the concomitant epicardial coronary artery disease (CAD) rather than the degree of coronary steal and its routine use in this setting is not supported.

Randomized trial of primary PCI with or without routine manual thrombectomy.

BACKGROUND: During primary percutaneous coronary intervention (PCI), manual thrombectomy may reduce distal embolization and thus improve microvascular perfusion. Small trials have suggested that thrombectomy improves surrogate and clinical outcomes, but a larger trial has reported conflicting results. METHODS: We randomly assigned 10,732 patients with ST-segment elevation myocardial infarction (STEMI) undergoing primary PCI to a strategy of routine upfront manual thrombectomy versus PCI alone. The primary outcome was a composite of death from cardiovascular causes, recurrent myocardial infarction, cardiogenic shock, or New York Heart Association (NYHA) class IV heart failure within 180 days. The key safety outcome was stroke within 30 days. RESULTS: The primary outcome occurred in 347 of 5033 patients (6.9%) in the thrombectomy group versus 351 of 5030 patients (7.0%) in the PCI-alone group (hazard ratio in the thrombectomy group, 0.99; 95% confidence interval [CI], 0.85 to 1.15; P=0.86). The rates of cardiovascular death (3.1% with thrombectomy vs. 3.5% with PCI alone; hazard ratio, 0.90; 95% CI, 0.73 to 1.12; P=0.34) and the primary outcome plus stent thrombosis or target-vessel revascularization (9.9% vs. 9.8%; hazard ratio, 1.00; 95% CI, 0.89 to 1.14; P=0.95) were also similar. Stroke within 30 days occurred in 33 patients (0.7%) in the thrombectomy group versus 16 patients (0.3%) in the PCI-alone group (hazard ratio, 2.06; 95% CI, 1.13 to 3.75; P=0.02). CONCLUSIONS: In patients with STEMI who were undergoing primary PCI, routine manual thrombectomy, as compared with PCI alone, did not reduce the risk of cardiovascular death, recurrent myocardial infarction, cardiogenic shock, or NYHA class IV heart failure within 180 days but was associated with an increased rate of stroke within 30 days. (Funded by Medtronic and the Canadian Institutes of Health Research; TOTAL ClinicalTrials.gov number, NCT01149044.).

Heparin use for diagnostic cardiac catheterization with a radial artery approach: An international survey of practice patterns.

OBJECTIVES: We aimed to describe global practice patterns of unfractionated heparin (UFH) use for diagnostic transradial cardiac catheterization. BACKGROUND: The use of the radial artery approach for cardiac catheterization is increasing globally. Limited contemporary data exist to support the use or optimal dosing of UFH to prevent radial artery occlusion (RAO) and other thromboembolic complications. METHODS: We performed a web-based international survey of 450 interventional cardiologists from 34 countries. We collected information regarding the experience and use of UFH for diagnostic transradial cardiac catheterization. RESULTS: The survey was conducted between June and July 2016 and was completed by 227 (50.4%) interventional cardiologists. Overall, 83.3% performed >75% of their coronary angiograms via a radial approach, with the plurality (41.9%) having 10-20 years of clinical experience. Of all respondents, 7.5% did not use UFH for routine diagnostic transradial heart catheterization. Of the 92.5% who did use UFH, it was preferentially administered intra-arterially by 60% and intravenously by 40%. The majority (62.6%) of interventionalists used a fixed UFH dose with 5,000 IU being the most common dose (used in 48%). For those using a weight-based UFH (50 IU/kg) dosing regimen for diagnostic procedures (36.1%), the administered UFH dose ranged from 2,000 up to 10,000 IU. CONCLUSIONS: Despite the lack of firm evidence, the majority of interventional cardiologists who participated in the survey use UFH to prevent RAO for diagnostic transradial coronary angiography. However, there exist large practice disparities with regards to dose and route of administration. Given this knowledge gap, a dedicated randomized trial is warranted.

Radial versus femoral approach for same-day inter-facility transfer for percutaneous coronary intervention.

BACKGROUND: The use of radial approach for coronary angiography, followed by same-day inter-facility transfer for percutaneous coronary intervention (PCI) has not yet been evaluated. OBJECTIVES: We sought to assess the safety and feasibility of using the transradial as compared to the transfemoral approach in patients undergoing diagnostic angiogram with same-day transfer to a PCI facility. METHODS: Patients that underwent diagnostic coronary angiography between January 2011 and June 2017 in a referring facility, and were transferred for same-day PCI were included. Patients' demographics, as well as procedural data and in-hospital outcome, were collected. RESULTS: Three hundred fifty-two participants were included. Of these, 36 (10.2%) patients received transradial access. Patients in the transradial group were older (68 ± 10 vs 62 ± 12 years, P = 0.007), and received a significantly higher total dose of heparin including both, diagnostic and PCI procedures (5935 ± 1865 vs 10029 ± 2771 units, P < 0.001). None of the transradial patients experienced bleeding or access-related complications. In the transfemoral group, 9 (3%) vascular-access complications were recorded. Contrast volume was lower for transradial patients (177 ± 47 vs 216 ± 75 mL, P < 0.001). A higher proportion of outpatients were discharged from the PCI-center the same day after transradial procedures (53% vs 1.3%, P < 0.001). CONCLUSIONS: Transradial access for inter-facility transfer for PCI after diagnostic angiogram appears safe and feasible, without increasing the risk for ischemic hand complications. Transradial access was associated with fewer bleeding and vascular access-site complications, and with a higher likelihood for a same-day discharge home in outpatients.

Long-term pharmacodynamic effects of Ticagrelor versus Clopidogrel in fibrinolytic-treated STEMI patients undergoing early PCI.

The long-term pharmacodynamic effects of Ticagrelor versus Clopidogrel in patients undergoing early percutaneous coronary intervention (PCI) after fibrinolytic therapy is unknown. From May 2014 to August 2016, 212 patients undergoing PCI within 24 h of Tenecteplase (TNK), Aspirin, and Clopidogrel for ST-elevated myocardial infarction (STEMI) were randomized at four Canadian sites to receive additional Clopidogrel or Ticagrelor initiated prior to PCI. The platelet reactivity units (PRU) were measured with the VerifyNow Assay before study drug administration (baseline), at 4 and 24 h post PCI, and follow-up appointment. A mixed-model analysis with time as the repeated measure and drug as the between-subjects factor was calculated using 2 separate 1 × 4 ANOVAs, with students t-tests used to compare drugs within each time point. Complete clinical follow-up data (median 115.0 days; IQR 80.3-168.8) was available in 50 patients (23.6%) randomized to either Clopidogrel (n = 23) or Ticagrelor (n = 27). Analyses revealed significant decreases in PRU from baseline to 4 h (261.4 vs. 71.7; Mdiff = - 189.7; p < 0.001) to 24 h (71.7 vs. 27.7; Mdiff = - 44.0; p < 0.001) to end of follow-up (27.7 vs.17.9; Mdiff = - 9.9. p = 0.016) for those randomized to Ticagrelor and significant decreases in PRU only from baseline to 4 h (271.3 vs. 200.8; Mdiff = - 70.5, p = < 0.001) in patients receiving Clopidogrel, and a significantly greater proportion of patients with adequate platelet inhibition (PRU < 208) on long-term follow-up (Clopidogrel, 82.6% vs. Ticagrelor, 100.0%; p = 0.038). Our results demonstrate that in patients undergoing PCI within 24 h of fibrinolysis for STEMI, Ticagrelor provides prolonged platelet inhibition compared with Clopidogrel.

Outcomes after thrombus aspiration for ST elevation myocardial infarction: 1-year follow-up of the prospective randomised TOTAL trial.

BACKGROUND: Two large trials have reported contradictory results at 1 year after thrombus aspiration in ST elevation myocardial infarction (STEMI). In a 1-year follow-up of the largest randomised trial of thrombus aspiration, we aimed to clarify the longer-term benefits, to help guide clinical practice. METHODS: The trial of routine aspiration ThrOmbecTomy with PCI versus PCI ALone in Patients with STEMI (TOTAL) was a prospective, randomised, investigator-initiated trial of routine manual thrombectomy versus percutaneous coronary intervention (PCI) alone in 10,732 patients with STEMI. Eligible adult patients (aged ≥18 years) from 87 hospitals in 20 countries were enrolled and randomly assigned (1:1) within 12 h of symptom onset to receive routine manual thrombectomy with PCI or PCI alone. Permuted block randomisation (with variable block size) was done by a 24 h computerised central system, and was stratified by centre. Participants and investigators were not masked to treatment assignment. The trial did not show a difference at 180 days in the primary outcome of cardiovascular death, myocardial infarction, cardiogenic shock, or heart failure. However, the results showed improvements in the surrogate outcomes of ST segment resolution and distal embolisation, but whether or not this finding would translate into a longer term benefit remained unclear. In this longer-term follow-up of the TOTAL study, we report the results on the primary outcome (cardiovascular death, myocardial infarction, cardiogenic shock, or heart failure) and secondary outcomes at 1 year. Analyses of the primary outcome were by modified intention to treat and only included patients who underwent index PCI. This trial is registered with ClinicalTrials.gov, number NCT01149044. FINDINGS: Between Aug 5, 2010, and July 25, 2014, 10,732 eligible patients were enrolled and randomly assigned to thrombectomy followed by PCI (n=5372) or to PCI alone (n=5360). After exclusions of patients who did not undergo PCI in each group (337 in the PCI and thrombectomy group and 331 in the PCI alone group), the final study population comprised 10,064 patients (5035 thrombectomy and 5029 PCI alone). The primary outcome at 1 year occurred in 395 (8%) of 5035 patients in the thrombectomy group compared with 394 (8%) of 5029 in the PCI alone group (hazard ratio [HR] 1·00 [95% CI 0·87-1·15], p=0·99). Cardiovascular death within 1 year occurred in 179 (4%) of the thrombectomy group and in 192 (4%) of 5029 in the PCI alone group (HR 0·93 [95% CI 0·76-1·14], p=0·48). The key safety outcome, stroke within 1 year, occurred in 60 patients (1·2%) in the thrombectomy group compared with 36 (0·7%) in the PCI alone group (HR 1·66 [95% CI 1·10-2·51], p=0·015). INTERPRETATION: Routine thrombus aspiration during PCI for STEMI did not reduce longer-term clinical outcomes and might be associated with an increase in stroke. As a result, thrombus aspiration can no longer be recommended as a routine strategy in STEMI. FUNDING: Canadian Institutes of Health Research, Canadian Network and Centre for Trials Internationally, and Medtronic Inc.

Effects of ticagrelor versus clopidogrel on platelet function in fibrinolytic-treated STEMI patients undergoing early PCI.

OBJECTIVES: Patients undergoing PCI early after fibrinolytic therapy are at high risk for both thrombotic and bleeding complications. We sought to assess the pharmacodynamic effects of ticagrelor versus clopidogrel in the fibrinolytic-treated STEMI patients undergoing early PCI. METHODS AND RESULTS: Patients undergoing PCI within 24 hours of tenecteplase (TNK), aspirin, and clopidogrel for STEMI were randomized to receive additional clopidogrel 300 mg followed by 75 mg daily or ticagrelor 180 mg followed by 90 mg twice daily. The platelet reactivity units (PRU) were measured with the VerifyNow Assay before study drug administration (baseline) at 4 and 24 hours post-PCI. The primary end point was PRU ≤208 at 4 hours. A total of 140 patients (74 in ticagrelor and 66 in clopidogrel group) were enrolled. The mean PRU values at baseline were similar for the 2 groups (257.8±52.9 vs 259.5±56.7, P=.85, respectively). Post-PCI, patients on ticagrelor, compared to those on clopidogrel, had significantly lower PRU at 4 hours (78.7±88 vs 193.6±86.5, respectively, P<.001) and at 24 hours (34.5±35.0 and 153.5±75.5, respectively, P<.001). The primary end point was observed in 87.8% (n=65) in the ticagrelor-treated patients compared to 57.6% (n=38) of clopidogrel-treated patients, P<.001. CONCLUSION: Fibrinolysis-treated STEMI patients who received clopidogrel and aspirin at the time of fibrinolysis and were undergoing early PCI frequently had PRU >208. In this high-risk population, ticagrelor provides more prompt and potent platelet inhibition compared with clopidogrel (Funded by Astra Zeneca; NCT01930591, https://clinicaltrials.gov/ct2/show/NCT01930591).

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

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

Baseline characteristics, adenosine diphosphate receptor inhibitor treatment patterns, and in-hospital outcomes of myocardial infarction patients undergoing percutaneous coronary intervention in the prospective Canadian Observational AntiPlatelet sTudy (COAPT).

BACKGROUND: Contemporary use of dual antiplatelet therapy and consistency with guideline recommendations in acute coronary syndrome patients undergoing percutaneous coronary intervention (PCI) have not been well characterized. METHODS: The COAPT was a prospective, observational, multicenter, longitudinal study of patients with myocardial infarction (MI) undergoing PCI. Baseline characteristics, treatment patterns, processes of care, factors associated with switching to and from novel adenosine diphosphate receptor inhibitors (ADPris), and in-hospital outcomes are described. RESULTS: Among 2,179 MI patients undergoing PCI during their index hospitalization, 1,328 (60.9%) had ST elevation. Initial ADPri use included clopidogrel in 1,812 (83.2%), prasugrel in 125 (5.7%), and ticagrelor in 242 (11.1%). At discharge, 1,597 patients (73.4%) were prescribed clopidogrel, 220 (10.1%) prasugrel, and 358 (16.5%) ticagrelor. Switching between ADPri therapies during the index hospitalization occurred in 15.3%, 22.4%, and 25.2% of patients initially started on clopidogrel, prasugrel, and ticagrelor, respectively. Most switches over the 15-month study period occurred during the index admission (16.8% of patients vs 4.4% switches postdischarge). Major adverse cardiovascular events occurred in 7.5% of patients during the index hospitalization. In-hospital bleeding events occurred in 6.0% of patients and most were mild. CONCLUSIONS: Despite randomized trial evidence and guideline recommendations, only a minority of Canadian MI patients undergoing PCI initially received or were discharged on one of the newer ADPri agents. These findings suggest an opportunity to improve upon the appropriate selection of the ADPris at index hospitalization and discharge in Canadian MI patients undergoing PCI.

Ischemic and bleeding events in patients with myocardial infarction undergoing percutaneous coronary intervention who require oral anticoagulation: Insights from the Canadian observational AntiPlatelet sTudy.

BACKGROUND: Since the introduction of newer, more potent P2Y12 receptor inhibitors (P2Y12ris), practice patterns and associated clinical outcomes in patients with myocardial infarction (MI) undergoing percutaneous coronary intervention (PCI) and also requiring oral anticoagulation (OAC) have not been fully characterized. METHODS: The Canadian Observational Antiplatelet Study was a prospective, multicenter, longitudinal, observational study (26 hospitals, December 2011 to May 2013) describing P2Y12ri treatment patterns and outcomes in patients with ST-elevation and non-ST-elevation MI undergoing PCI. We describe the clinical characteristics, treatment patterns, bleeding, and ischemic outcomes over the 15-month follow-up within and between the subgroups of patients discharged on either dual-antiplatelet therapy (DAPT) (acetyl salicylic acid [ASA]+P2Y12ri) or triple therapy (ASA+P2Y12ri+OAC). RESULTS: Of the 2,034 patients at discharge, 86% (n = 1,757) were on DAPT, whereas 14% (n = 277) were on triple therapy (50% warfarin, 50% non-vitamin K OAC [NOAC]). The frequency of newer P2Y12ri use (prasugrel or ticagrelor) was similar in the DAPT and triple therapy groups (28% vs 26%, respectively). In the triple therapy group, NOAC use was higher in those receiving a new P2Y12ri compared to those receiving clopidogrel (75% vs 41%, respectively, P < .0001). The unadjusted and adjusted events of major cardiovascular event (MACE) and bleeding were higher in the triple therapy group. For patients on triple therapy, the bleeding or MACE events were not significantly different between those on clopidogrel versus those on ticagrelor or prasugrel. CONCLUSION: In this observational study of MI patients requiring PCI, 1 in 8 were discharged on triple antithrombotic therapy, of whom 26% were on newer P2Y12ris. Patients on triple therapy had higher risk at baseline, with higher unadjusted and adjusted MACE and bleeding events compared to those on DAPT alone. Among triple therapy-treated patients, there was no difference in the MACE and bleeding events regardless of the P2Y12ri used.

Culprit lesion thrombus burden after manual thrombectomy or percutaneous coronary intervention-alone in ST-segment elevation myocardial infarction: the optical coherence tomography sub-study of the TOTAL (ThrOmbecTomy versus PCI ALone) trial.

AIMS: Manual thrombectomy has been proposed as a strategy to reduce thrombus burden during primary percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarction (STEMI). However, the effectiveness of manual thrombectomy in reducing thrombus burden is uncertain. In this substudy of the TOTAL (ThrOmbecTomy versus PCI ALone) trial, we compared the thrombus burden at the culprit lesion using optical coherence tomography (OCT) in patients treated with thrombectomy vs. PCI-alone. METHODS AND RESULTS: The TOTAL trial (N = 10 732) was an international, multicentre, randomized trial of thrombectomy (using the Export catheter, Medtronic Cardiovascular, Santa Rosa, CA, USA) in STEMI patients treated with primary PCI. The OCT substudy prospectively enrolled 214 patients from 13 sites in 5 countries. Optical coherence tomography was performed immediately after thrombectomy or PCI-alone and then repeated after stent deployment. Thrombus quantification was performed by an independent core laboratory blinded to treatment assignment. The primary outcome of pre-stent thrombus burden as a percentage of segment analysed was 2.36% (95% CI: 1.73-3.22) in the thrombectomy group and 2.88% (95% CI: 2.12-3.90) in the PCI-alone group (P = 0.373). Absolute pre-stent thrombus volume was not different (2.99 vs. 3.74 mm(3), P = 0.329). Other secondary outcomes of pre-stent quadrants of thrombus, post-stent atherothrombotic burden, and post-stent atherothrombotic volume were not different between groups. CONCLUSION: Manual thrombectomy did not reduce pre-stent thrombus burden at the culprit lesion compared with PCI-alone. Both strategies were associated with low thrombus burden at the lesion site after the initial intervention to restore flow.

The Impact of Peripheral Nerve Stimulation on Coronary Blood Flow and Endothelial Function.

PURPOSE: The geko™ device is a small transcutaneous nerve stimulator that is applied non-invasively to the skin over the common peroneal nerve to stimulate peripheral blood flow. The purpose of this study was to investigate the effect of peripheral nerve stimulation on coronary flow dynamics and systemic endothelial function. METHODS: We enrolled 10 male patients, age 59 ± 11 years, with symptomatic obstructive coronary disease undergoing percutaneous coronary intervention (PCI). Coronary flow dynamics were assessed invasively using Doppler flow wire at baseline and with nerve stimulation for 4 min. Measurements were taken in the stenotic coronary artery and in a control vessel without obstructive disease. At a separate visit, peripheral blood flow at the popliteal artery (using duplex ultrasound assessment) and endothelial function assessed by peripheral artery tonometry (PAT) were measured at baseline and after one hour of nerve stimulation. RESULTS: Compared to baseline, there was a significant increase in coronary blood flow as measured by average peak velocity (APV) in the control vessel with nerve stimulation (20.3 ± 7.7 to 23.5 ± 10 cm/s; p = 0.03) and non-significant increase in the stenotic vessel (21.9 ± 12 to 23.9 ± 12.9 cm/s; p = 0.23). Coronary flow reserve did not change significantly. Reactive hyperemia-peripheral arterial tonometry (Rh-PAT) increased from 2.28 ± 0.39 to 2.67 ± 0.6, p = 0.045. CONCLUSIONS: A few minutes of peripheral nerve stimulation may improve coronary blood flow. This effect is more prominent in non-stenotic vessels. Longer stimulation improved endothelial function.