MGuard mesh-covered stent for treatment of ST-segment elevation myocardial infarction with high thrombus burden despite manual aspiration.

OBJECTIVES: To assess the usefulness of the MGuard stent in patients with ST-segment elevation myocardial infarction (STEMI) in whom a high thrombus burden persists after manual aspiration. BACKGROUND: In some patients with STEMI, a high thrombus burden may persist after manual aspiration. These patients may be at high risk of distal embolization and therefore impaired myocardial reperfusion. The MGuard is a novel mesh-covered stent designed to minimize thrombus embolization. METHODS: Single-arm, prospective registry of patients with STEMI and high thrombus burden after aggressive thrombus aspiration treated with the MGuard stent. High thrombus burden was defined as thrombus burden grade 4 or 5 according to the TIMI score. Lesions with a side branch ≥2 mm and patients with cardiogenic shock were not included. The study end-points were proportion of final TIMI 3 flow, normal myocardial blush, and complete ST-segment resolution. RESULTS: Fifty-six patients were included. After MGuard stent implantation >85% of cases had thrombus score = 0. Final TIMI 3 flow was achieved in 82% of cases, normal myocardial blush in 55%, and complete ST-segment resolution in 59%. Occlusion of a side branch (<2 mm) occurred in 2 cases (3.5%), embolization to a distal branch in 5 cases (8.9%), and transient no-reflow in 4 cases (7.1%). Major adverse cardiac events rate at 9 months was 3.6%, including 1 definite acute stent thrombosis and 1 target-vessel revascularization. CONCLUSIONS: The MGuard stent may be useful to prevent distal embolization in patients with STEMI and high thrombus burden despite mechanical aspiration.

Revascularized ST-segment elevation myocardial infarction. Temporal trends in contemporary therapies and impact on outcomes.

INTRODUCTION AND OBJECTIVES: To assess, in patients with ST-segment elevation myocardial infarction (STEMI) who underwent primary percutaneous intervention, the pace of introduction in clinical practice (2010-2017) of drug-eluting stents (DES), ticagrelor, prasugrel, and prolonged dual antiplatelet therapy (DAPT) duration, and their potential impact on the risk of 2-year outcomes. METHODS: Prospective and exhaustive community-wide cohort of 14 841 STEMI patients undergoing primary percutaneous intervention between 2010 and 2017. Index episodes were obtained from the Catalan Codi IAM Registry, events during follow-up from the Minimum Data Set and DAPT were defined by pharmacy dispensation. Follow-up was 24 months. The temporal trend for exposures and outcomes was assessed using regression models. RESULTS: Age> 65 years, diabetes, renal failure, previous heart failure, and need for anticoagulation at discharge were more frequent in later periods (P <.001). From 2010 to 2017, the use of DES increased from 31.1% to 69.8%, ticagrelor from 0.1% to 28.6%, prasugrel from 1.5% to 23.8%, and the median consecutive months on DAPT from 2 to 10 (P <.001 for all). Adjusted analysis showed a temporal trend to a lower risk of the main outcome over time: the composite of death, acute myocardial infarction, stroke and repeat revascularization (absolute odds reduction 0.005% each quarter; OR, 0.995; 95%CI, 0.99-0.999; P=.028). The odds of all individual components except stroke were reduced, although significance was only reached for revascularization. CONCLUSIONS: Despite a strong increase between 2010 and 2017 in the use and duration of DAPT and the use of ticagrelor, prasugrel and DES, there was no substantial reduction in major cardiovascular outcomes.

Persistence with dual antiplatelet therapy after percutaneous coronary intervention for ST-segment elevation acute coronary syndrome: a population-based cohort study in Catalonia (Spain).

OBJECTIVES: Guidelines recommending 12-month dual antiplatelet therapy (DAPT) in patients with ST-elevation acute coronary syndrome (STEACS) undergoing percutaneous coronary intervention (PCI) were published in year 2012. We aimed to describe the influence of guideline implementation on the trend in 12-month persistence with DAPT between 2010 and 2015 and to evaluate its relationship with DAPT duration regimens recommended at discharge from PCI hospitals. DESIGN: Observational study based on region-wide registry data linked to pharmacy billing data for DAPT follow-up. SETTING: All PCI hospitals (10) belonging to the acute myocardial infarction (AMI) code network in Catalonia (Spain). PARTICIPANTS: 10 711 STEACS patients undergoing PCI between 2010 and 2015 were followed up. PRIMARY AND SECONDARY OUTCOME MEASURES: Primary outcome was 12-month persistence with DAPT. Calendar year quarter, publication of guidelines, DAPT duration regimen recommended in the hospital discharge report, baseline patient characteristics and significant interactions were included in mixed-effects logistic regression based interrupted time-series models. RESULTS: The proportion of patients on-DAPT at 12 months increased from 58% (56-60) in 2010 to 73% (71-75) in 2015. The rate of 12-month persistence with DAPT significantly increased after the publication of clinical guidelines with a time lag of 1 year (OR=1.20; 95% CI 1.11 to 1.30). A higher risk profile, more extensive and complex coronary disease, use of drug-eluting stents (OR=1.90; 95% CI 1.50 to 2.40) and a 12-month DAPT regimen recommendation at discharge from the PCI hospital (OR=5.76; 95% CI 3.26 to 10.2) were associated with 12-month persistence. CONCLUSION: Persistence with 12-month DAPT has increased since publication of clinical guidelines. Even though most patients were discharged on DAPT, only 73% with potential indication were on-DAPT 12 months after PCI. A guideline-based recommendation at PCI hospital discharge was highly associated with full persistence with DAPT. Establishing evidence-based, common prescribing criteria across hospitals in the AMI-network would favour adherence and reduce variability.

Preserved endothelial vasomotor function after everolimus-eluting stent implantation.

AIMS: To compare the degree of endothelial dysfunction (ED) in patients treated with everolimus-eluting stent (EES) versus bare metal stent (BMS) implantation. METHODS AND RESULTS: This is an observational study. A total of 30 elective patients (15 treated with EES and 15 with BMS) were recruited. All patients underwent coronary angiography and intracoronary acetylcholine (Ach) test at different doses at six months after stent implantation. Quantitative coronary angiography analysis was performed to evaluate the changes in mean luminal diameter (MLD) of the segments distal to the distal stent edge after increasing doses of Ach. Both EES and BMS groups had similar baseline characteristics except for stent length (18.6±2.5 vs. 16.5±2.5 mm; p=0.033) and diameter (3.1±0.2 vs. 3.4±0.3 mm; p=0.007). The vasomotion test showed that EES had 3.14% of MLD decrease after Ach infusion and BMS had 2.35% of vasoconstriction (p=0.62). After adjustment for baseline characteristics, no statistical difference was observed between groups. CONCLUSIONS: In our study EES implantation was associated with a low degree of ED and had a similar vasomotion response as compared to BMS. Prospective randomised investigations are warranted to confirm these findings.

Lumen enlargement of the coronary segments located distal to chronic total occlusions successfully treated with drug-eluting stents at follow-up.

AIMS: Chronic total occlusions (CTO) are the final stage of atherosclerosis. Occluded coronary arteries have large plaque burden and negative remodelling. The aim of this study was to assess lumen and vessel changes of segments located distal to successfully recanalised CTO. METHODS AND RESULTS: Ninety-one CTO treated with drug-eluting stents underwent quantitative coronary angiography (QCA) at baseline and at 12-18 months; 31 underwent serial intravascular ultrasound (IVUS) imaging. Angiographic changes were assessed with QCA as differences in minimal, mean and maximal lumen diameter (MinLD, MeanLD and MaxLD, respectively). Vessel changes were assessed with IVUS as changes in plaque and vessel volume. At follow-up, angiographic MinLD increased 23.9% (from 0.88±0.32 to 1.09±0.35 mm; p<0.01), MeanLD 16.4% (from 1.59±0.44 to 1.85±0.45 mm; p<0.01) and MaxLD 11.7% (from 2.39±0.67 to 2.67±0.70 mm; p<0.01). Lumen enlargement was greater in non-restenotic lesions, small lumen area at the end of the index procedure and low LDL-cholesterol levels during the study. By IVUS, lumen volume increased 26.9% (from 108.1±89.2 to 137.3±115.3 mm3; p<0.01), vessel volume increased 12.1% (from 207.1±170.2 to 232.2±196.0 mm3; p<0.01) and plaque volume tended to decrease 3.9% (from 98.9±88.7 to 94.9±89.3 mm3; p=0.07). Small lumen at baseline was related to greater lumen enlargement. CONCLUSIONS: Segments distal to recanalised CTO showed a notable lumen and vessel enlargement with a trend toward mild plaque regression. Low LDL-cholesterol levels increase lumen enlargement.

Impact of mild hypothermia on platelet responsiveness to aspirin and clopidogrel: an in vitro pharmacodynamic investigation.

UNLABELLED: The combination of percutaneous coronary intervention (PCI) and therapeutic hypothermia in comatose patients after cardiac arrest due to an acute coronary syndrome has been reported to be safe and effective. However, recent investigations suggest that hypothermia may be associated with impaired response to clopidogrel and greater risk of thrombotic complications after PCI. This investigation aimed to evaluate the effect of hypothermia on the pharmacodynamic response of aspirin and clopidogrel in patients (n = 20) with ST elevation myocardial infarction undergoing primary PCI. Higher platelet reactivity (ADP stimulus) was observed in samples incubated at 33 °C compared with those at 37 °C (multiple electrode aggregometry, 235.2 ± 31.4 AU×min vs. 181.9 ± 30.2 AU×min, p < 0.001; VerifyNow P2Y12, 172.9 ± 20.3 PRU vs. 151.0 ± 19.3 PRU, p = 0.004). Numerically greater rates of clopidogrel poor responsiveness were also observed at 33 °C. No differences were seen in aspirin responsiveness. In conclusion, mild hypothermia was associated with reduced clopidogrel-mediated platelet inhibition with no impact on aspirin effects. CLINICAL RELEVANCE: Mild therapeutic hypothermia is associated with impaired response to clopidogrel therapy, which might contribute to increase the risk of thrombotic events in ACS comatose patients undergoing PCI.

Clopidogrel pretreatment in primary percutaneous coronary intervention: prevalence of high on-treatment platelet reactivity and impact on preprocedural patency of the infarct-related artery.

To date, there is limited data on levels of platelet inhibition achieved in patients with ST-elevation myocardial infarction (STEMI) who are loaded with clopidogrel and aspirin (ASA) prior to undergoing primary percutaneous coronary intervention (P-PCI). The aim of this investigation was to evaluate the percentage of STEMI patients with high on-treatment platelet reactivity (HPR) to clopidogrel at the time of initiating P-PCI and its association with the initial patency of the infarct-related artery (IRA). This prospective pharmacodynamic study included 50 STEMI patients, previously naïve to oral antiplatelet agents, who received 500-mg ASA and 600-mg clopidogrel loading doses prior to P-PCI. Platelet function assessment was performed at the beginning of the procedure using various assays, including VerifyNow™ system (primary endpoint), light transmission aggregometry and multiple electrode aggregometry. The percentage of patients with suboptimal response to clopidogrel and ASA assessed with the VerifyNow™ system was 88.0% and 28.6%, respectively. Similar results were obtained with the other assays used. A higher percentage of patients with initial patency of the IRA was observed among those patients without HPR compared with those with HPR to clopidogrel (66.7% vs 15.9%; p=0.013), while no differences were observed regarding postprocedural angiographic or electrocardiographic outcomes. In conclusion, this study shows that a high percentage of STEMI patients have inadequate levels of clopidogrel-induced and, to a lesser extent, aspirin-mediated platelet inhibition when starting a P-PCI procedure, and suggests that a poor response to clopidogrel might be associated with impaired initial TIMI flow in the IRA.

Global risk score for choosing the best revascularization strategy in patients with unprotected left main stenosis.

BACKGROUND: Coronary artery bypass graft (CABG) is recommended for patients with unprotected left main stenosis (ULMS). Percutaneous coronary intervention (PCI) is only recommended in specific anatomic conditions as in patients with low/mid SYNTAX score (SS). The aim of this study was to assess if the clinical and anatomic global risk classification (GRC) can enhance the indication of both revascularization therapies. METHODS: A total of 407 patients with ULMS treated with CABG (n = 285) or PCI (n = 122) were prospectively collected. The decision to treat with CABG or PCI was dependent on patient and physician's choice. Patients with ST-elevation myocardial infarction, shock, or valve disease were excluded. Clinical follow-up was obtained at 3 years. RESULTS: Patients with low GRC (n = 151) treated with CABG vs those with PCI had similar cardiac mortality (5.9% vs 0%, respectively; P=.17) and major adverse cardiac events (MACE; 18.5% vs 12.5%, respectively; P=.40). Patients classified as mid GRC (n = 175) had similar cardiac death (11.1% vs 10.3%; P=.85) and MACE rates (20.7% vs 22.4%; P=.92) with CABG or PCI, respectively. Patients with high GRC (n = 81) treated with CABG had numerically fewer cardiac deaths (16.3% vs 28.1%; P=.16) and lower MACE rates (24.5% vs 40.6%; P=.048) than with PCI. Statistical models using the GRC as a predictor of cardiac death showed better goodness-of-fit than the SS. CONCLUSION: Patients with low/mid GRC have similar mid-term outcomes with either CABG or PCI; patients with high GRC seem to benefit from CABG. Although further investigations are required, GRC is a better predictor of outcomes than SS.

Impact on delay times and characteristics of patients undergoing primary percutaneous coronary intervention in the southern metropolitan area of Barcelona after implementation of the infarction code program.

INTRODUCTION AND OBJECTIVES: A standardized protocol of emergent transfer for primary percutaneous coronary intervention for patients with ST elevation myocardial infarction, defined as the Infarction Code, was implemented in June 2009 in the Catalan regional health system. The objective of this study was to evaluate the impact of the new protocol on delay times, number of procedures and clinical characteristics compared with the previous period in the population of patients referred to our hospital. METHODS: All consecutive patients undergoing primary percutaneous coronary intervention in our hospital were prospectively registered. The clinical characteristics, delay times and mortality in the follow-up of the protocol implementation period (June 2009-May 2010) were analyzed and compared with the previous year (June 2008-May 2009). RESULTS: During the protocol period, 514 patients were included, compared with 241 in the previous year. Age, cardiovascular risk factors, anterior myocardial infarction and procedure characteristics were similar in the 2 groups. The first medical contact to balloon time was lower in the protocol period (median time 120 min vs 88 min; P<.001). Patients in the protocol period showed a trend toward less severe disease (Killip III, rescue angioplasty). The multivariate regression analysis showed a significant association between 1-year mortality and age, Killip class ≥ III at admission, anterior infarction and 3-vessel disease. CONCLUSIONS: The introduction of the Infarction Code program increased the number of patients treated by primary percutaneous coronary intervention with a reduction in delay times and better clinical characteristics at presentation. Full English text available from:www.revespcardiol.org.

Long-term follow-up after percutaneous treatment of the unprotected left main stenosis in high risk patients not suitable for bypass surgery.

INTRODUCTION AND OBJECTIVES: Percutaneous coronary intervention is recommended in patients with unprotected left main stenosis non suitable for coronary artery bypass graft. Long-term follow-up of those patients remains uncertain. METHODS: All patients with de novo unprotected left main stenosis treated with stent implantation were consecutively enrolled. Percutaneous coronary intervention was indicated according to the standards of care, taking into account clinical and anatomical conditions unfavorable for coronary artery bypass graft. The primary end point was the occurrence of major adverse cardiac events, a composite of death, nonfatal acute myocardial infarction, or target lesion revascularization. RESULTS: Of 226 consecutive patients included, 202 (89.4%) were treated with drug-eluting stents. Mean age was 72.1 years, 41.1% had renal dysfunction, and mean Syntax score and EuroSCORE were 28.9 and 7.4, respectively. Angiographic and procedural success was achieved in 99.6% and 92.9% of patients. At 3 years, the rates of major adverse cardiac events, death, nonfatal acute myocardial infarction and target lesion revascularization were 36.2%, 25.2%, 8.4%, 8.0%, respectively. Target lesion revascularization was more frequently observed when ≥ 2 stents were implanted rather than a single stent (18.5% vs 5.8%, P=.03); and with bare metal stents rather than drug-eluting stents (13.0% vs 7.9%, P=.24). Definite stent thrombosis was observed in 2 patients (0.9%) and probable stent thrombosis in 7 (3.1%). Female sex, impaired left ventricular function, and use of bare metal stents were significantly related with all-cause mortality. CONCLUSIONS: High-risk patients with unprotected left main stenosis treated with percutaneous coronary intervention presented with a high rate of major adverse cardiac events at long-term follow-up. Female sex, impaired left ventricular function, and use of bare metal stents were predictors of poor prognosis.