Reperfusion Therapy For ST-elevation Myocardial Infarction Research Articles

Implications of ischaemic area at risk and mode of reperfusion in ST-elevation myocardial infarction

ObjectiveUncertainty exists concerning the relative merits of pharmacological versus mechanical coronary reperfusion in patients presenting early with ST-elevation myocardial infarction (STEMI) with extensive myocardium at risk. Accordingly, we investigated whether...

Inequalities in reperfusion therapy for STEMI.

This editorial refers to “Reperfusion therapy for ST-elevation acute myocardial infarction in Eastern Europe: the ISACS-TC registry”, by E. Cenko et al ., on page 45. Reperfusion therapy, either by intravenous fibrinolysis or percutaneous coronary intervention (PCI), is the cornerstone of the management of ST-elevation myocardial infarction (STEMI).1 Randomized data have demonstrated its effectiveness in reducing mortality and morbidity, and the benefit is all the greater when it is performed early.2,3 As such, coronary reperfusion for STEMI performed within a short time frame is recommended and its timely implementation used as an indicator of quality of care.4 The estimated times to reperfusion also contribute largely to the choice of reperfusion strategy, with primary PCI being the technique of choice except if it is estimated that it cannot be performed within 120 min.1 Despite this, many patients fail to receive guideline-indicated therapies for STEMI and the proportion who do varies geographically.5 Addressing the variation in STEMI care will help reduce the substantial difference in mortality rates from cardiovascular disease between European countries.6 The choice of reperfusion strategy and the ability to … [↵][1]*Corresponding author. Tel: +44 01133438916, Email: c.p.gale{at}leeds.ac.uk [1]: #xref-corresp-1-1

Coronary artery reperfusion for ST elevation myocardial infarction is associated with shorter cycle length ventricular tachycardia and fewer spontaneous arrhythmias

Ventricular tachycardia (VT) induction at electrophysiological (EP) study early after ST elevation myocardial infarction (STEMI) has been a predictor of spontaneous ventricular arrhythmia. Reperfusion therapy for STEMI may have resulted in altered VT character. We attempted to determine differences in VT cycle length (CL) and VT recurrence rates, in patients who received early and late reperfusion treatment for STEMI. Of 180 consecutive patients with left ventricular ejection fraction < 40%, 77 patients had positive EP studies. Forty-nine patients receiving early reperfusion treatment (group 1, n = 49) were compared with 28 patients who received late reperfusion (group 2; n = 28). Seventy-five patients had defibrillators implanted for primary prevention of sudden death. Patients were followed for up to 6 years to assess long-term rates of spontaneous ventricular tachyarrhythmia. Patients who received early reperfusion demonstrated shorter CL inducible VT (231 ± 43 ms vs. 252 ± 56 ms; P = 0.016). They also had fewer spontaneous arrhythmias (adjusted hazard ratio of 2.94, 95% confidence interval: 1.07-8.13; P = 0.03) with shorter CL spontaneous VT (266 ± 54 ms vs. 320 ± 80 ms; P = 0.02) at 53 ± 33 months. Ventricular tachycardia CL was the only independent predictor of spontaneous arrhythmia or sudden cardiac death (1.22, 1.07-1.47; P = 0.016). Patients receiving early reperfusion for STEMI had faster inducible and spontaneous VT and fewer spontaneous recurrences. This may be due to changes in the myocardial substrate as a result of early coronary artery reperfusion.

Do clinical factors explain persistent sex disparities in the use of acute reperfusion therapy in STEMI in Sweden and Canada?

This study examined clinical factors associated with sex differences in the use of acute reperfusion therapy (fibrinolysis or primary percutaneous coronary intervention) in ST-elevation myocardial infarction (STEMI) patients, and the interaction between sex and these factors in Sweden and Canada. Patients with STEMI in Sweden (n=32,676 from the Register of Information and Knowledge about Swedish Heart Intensive Care Admissions) were compared with similar patients in Canada (n=3375 from the Canadian Global Registry of Acute Coronary Events) for the period 2004-2008. Unadjusted vs. age-adjusted odds ratios (OR) for no reperfusion (women vs. men) were for Sweden 1.57 (95% CI 1.49-1.64) vs. 1.14 (95% CI 1.08-1.20), and for Canada 1.61 (95% CI 1.39-1.87) vs. OR 1.18 (95% CI 1.01-1.39). Sex differences persisted after multivariable adjustments (including prehospital delay, atypical symptoms, diabetes), factors for which no interaction with sex was found. Among women <60 years, adjusting for atypical symptoms in Canada and angiographic data in Sweden made the greatest contribution to explaining observed sex differences. In both countries, acute reperfusion therapy in STEMI was used less often in women than in men. Factors associated with these sex differences appear to differ between older and younger women. Targeted interventions are needed to optimize care for women with STEMI, as well as sex- and age-stratified reporting of quality indicators to assess their effectiveness.

Care of acute myocardial infarction in the coronary care units of Piedmont in 2007

The treatment of acute myocardial infarction (AMI), both with ST-segment elevation [ST-elevation myocardial infarction (STEMI)] and non-ST-segment elevation [non-ST-elevation myocardial infarction (NSTEMI)], is evolving in Piedmont, with an increase in interventional procedures and hub-and-spoke networks. This new region-wide survey provides updated assessment of the management of STEMI and unprecedented data on NSTEMI. In 30 coronary care units in Piedmont, all patients with AMI symptoms of duration less than 48 h, between January and March 2007, were included. Of 921 patients, 447 had STEMI and 474 NSTEMI. Diabetes was present in 35% and chronic kidney disease in 38%. Hospital mortality was 4.7% [95% confidence interval (CI) 3.3-6.1]: age 75 years or older, Killip class higher than 1 and known diabetes or abnormal blood glucose on admission were multivariate predictors. Thrombolysis and primary percutaneous transluminal coronary angioplasty (pPTCA) were performed in 17.6 and 53.1% of 391 patients, respectively, with STEMI of 12 h or less, and 29.3% had no reperfusion therapy, notably 52% of patients aged 75 years or older and 51% of those reaching non-24/24 h interventional centres. Mortality after pPTCA was 2.5% and onsite door-to-balloon time was less than 90 min in 67.5%. Overall mortality after STEMI was 5.4% (95% CI 3.2-7.6). In NSTEMI, use of antithrombotic treatments was extensive, but invasive treatment within 72 h was limited to 8% of patients in centres without interventional facilities and independent of patient's risk profile. Mortality after NSTEMI was 4.0% (95% CI 2.2-5.8) and was predicted by both the Global Registry of Acute Coronary Events risk score and diabetes. There is room for improvement in the treatment of AMI in our region, with more extensive use of reperfusion therapy in STEMI, especially in the elderly, and early revascularization and optimal medical treatment in higher-risk NSTEMI.

Quantitative Analysis of Peripheral Benzodiazepine Receptor in the Human Brain Using PET with 11C-AC-5216

Peripheral benzodiazepine receptor (PBR) is upregulated in activated glial cells and is therefore a useful biomarker for inflammation in the brain and neurodegenerative disorders. We developed a new PET radioligand, (11)C-AC-N-benzyl-N-ethyl-2-(7-methyl-8-oxo-2-pheyl-7,8-dihydro-9H-purin-9-yl)acetamide ((11)C-AC-5216), that allows the imaging and quantification of PBRs in monkey and mouse brains. The aim of this study was to evaluate a quantification method of (11)C-AC-5216 binding in the human brain. A 90-min dynamic PET scan was obtained for each of 12 healthy men after an intravenous injection of (11)C-AC-5216. Regions of interest were drawn on several brain regions. Binding potential, compared with nondisplaceable uptake (BP(ND)), was calculated by a nonlinear least-squares fitting (NLS) method with the 2-tissue-compartment model, and total volume of distribution (V(T)) was estimated by NLS and graphical analysis methods. BP(ND) was highest in the thalamus (4.6 +/- 1.0) and lowest in the striatum (3.5 +/- 0.7). V(T) obtained by NLS or graphical analysis showed regional distribution similar to BP(ND). However, there was no correlation between BP(ND) and V(T) because of the interindividual variation of K(1)/k(2). BP(ND) obtained with data from a scan time of 60 min was in good agreement with that from a scan time of 90 min (r = 0.87). Regional distribution of (11)C-AC-5216 was in good agreement with previous PET studies of PBRs in the human brain. BP(ND) is more appropriate for estimating (11)C-AC-5216 binding than is V(T) because of the interindividual variation of K(1)/k(2). (11)C-AC-5216 is a promising PET ligand for quantifying PBR in the human brain.

Primary PCI as the preferred reperfusion therapy in STEMI: it is a matter of time

There is a continuing controversy about the acceptable time-window for primary percutaneous coronary intervention (PPCI) in patients with ST-elevation myocardial infarction (STEMI). Recent American and European guidelines recommend PPCI if...

Guidelines for Therapy of ST-Segment–Elevation Acute Myocardial Infarction in Patients Presenting to Partners HealthCare System Hospital Emergency Departments

A major focus for individuals and organizations that study the quality of cardiovascular care is the timeliness of treatment for those patients who suffer an acute ST-elevation myocardial infarction (STEMI). We sought to develop guidelines that would inform the development and management of a more standardized approach to the treatment of STEMI within the 5 acute care hospitals that make up the Partners Healthcare acute care hospital network. In recent years much has been learned about how to deliver timely reperfusion therapy in STEMI and how to assess its outcome. As a component of the organization's mandate to promote the uniform high quality of care throughout the system, our group began studying the many aspects of the current treatment of STEMI within the system, we reviewed, summarized and debated the relevant literature, studied best practices and made recommendations for a system-wide approach to this problem. Our methods have included literature review, consultation with local and national experts, site visits throughout the system, web-based surveys of current attitudes within the system, interviews with stakeholders and consensus-development conferences. The result was not only the development of the following guidelines for therapy, but also an ongoing commitment to share patient-level data and outcomes for continuous quality assessment and improvement.

Ischaemic symptoms, quality of care and mortality during myocardial infarction

Objective:To study in myocardial infarction (MI) whether documentation of ischaemic symptoms is associated with quality of care and outcomes, and to compare patient reports of ischaemic symptoms during interviews with...

Myocardial infarction: contemporary management strategies

Myocardial infarction (MI) is a common clinical diagnosis, associated with significant morbidity and mortality, not only in the short term, but also years following the index event. A more complete understanding of the pathophysiology of MI has ushered the era of multipronged treatment approach, with a combination of goal-directed revascularization, a broad adjunctive pharmacological therapy and aggressive secondary prevention measures. The goals of this article are to review the basic pathophysiological processes, which lead up to a clinical diagnosis of MI, to highlight the essential elements of clinical presentation and to summarize the evidence for comprehensive therapy. Emphasis has been placed on the choice of primary reperfusion therapy for ST-elevation MI, on risk-stratification of patients with non-ST elevation MI, and on rationale behind the selection of anti-ischaemic and antithrombotic therapy. Finally, evidence-based approach to secondary prevention is outlined.