Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0022116 (ischemia)
 91,303 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Thrombotic occlusion is responsible for most acute manifestations of coronary artery disease, including unstable angina and non-Q-wave myocardial infarction. Antiplatelet therapy plays a major role in reducing the risk of ischemic events in such patients. Since thrombin generation is vital to the pathogenesis of thrombosis, recent studies have focused on thrombin inhibition in the management of acute ischemia. Heparin is the most widely used anticoagulant for acute management of thrombosis and is the treatment of choice in preventing and treating venous thromboembolism. Given in therapeutic doses intravenously, it is more effective than aspirin in reducing the risk of death or myocardial infarction in patients with unstable angina. Low-molecular-weight (LMW) heparins have improved pharmacologic and pharmacokinetic properties over standard heparin that may result in greater efficacy and safety. LMW heparins may be given in a fixed dose subcutaneously without monitoring, resulting in greater clinical utility and cost-effectiveness compared with standard heparin. Given subcutaneously in fixed, weight-adjusted doses they are more effective and safer than intravenous heparin in treating deep-vein thrombosis. Several studies have evaluated LMW heparins in unstable angina. In a small open trial, LMW heparin (nadroparin) reduced the risk of acute myocardial infarction compared with aspirin alone or a combination of aspirin and standard heparin. In 2 large clinical trials, LMW heparin (dalteparin) has been shown to be effective in the management of unstable angina with a 63% reduction in risk of death or acute myocardial infarction over patients treated with aspirin alone (Fragmin during Instability in Coronary Artery Disease; FRISC) and to be as effective as intravenous heparin (Fragmin in Unstable Coronary Artery Disease; FRIC).
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PMID:New frontiers in the management of unstable coronary artery disease. 929 65

The Fragmin and/or Early Revascularisation during Instability in Coronary Artery Disease (FRISC II) trial will, in a prospective multicenter factorially randomized study, compare the efficacy of 3 months continuation of subcutaneous treatment with the low-molecular-weight heparin dalteparin (Fragmin) with that of placebo and will also compare a direct invasive strategy with a stepwise selective approach with regard to the utilization of coronary angiography and revascularization in patients with unstable coronary artery disease. The primary endpoints are death or myocardial infarction after 3 and 6 months respectively. Secondary endpoints are the same events after 12-24 months and also cardiac symptoms, exercise capacity, and/or signs of myocardial ischemia, readmission, and costs. Analyses will also be made of subgroups based on inclusion diagnosis, initial elevation of biochemical markers of myocardial damage, elevation of fibrinogen or C-reactive protein, signs of ischemia in electrocardiography at rest or at continuous 24-hour ischemia monitoring, and left ventricular function at echocardiography. Altogether, 3,100 patients will be recruited in 65-70 Scandinavian centers. Completion of follow-up is anticipated in the second half of 1998. The FRISC II study will further elucidate new alternatives for antithrombotic, invasive, and individually tailored treatment of unstable coronary syndromes.
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PMID:Long-term low-molecular-weight heparin (Fragmin) and/or early revascularization during instability in coronary artery disease (the FRISC II Study). 929 73

A crucial question in the acute management of the patient with unstable coronary artery disease (UCAD) is whether to carry out early intervention, performing angiography soon after presentation and following this with revascularization where appropriate, or whether to follow a noninvasive medical strategy as far as possible unless symptoms necessitate intervention. The body of literature addressing this question is sparse, but the recent Fast Revascularization during InStability in Coronary artery disease (FRISC II) study has provided new insights into the problem. Using a factorial design to randomize patients to invasive or noninvasive management strategies, and to short- or long-term treatment with the low-molecular-weight heparin (LMWH) dalteparin sodium (Fragmin), it was shown in FRISC II that early invasive treatment (within 7 days), when combined with optimal medical pretreatment with dalteparin sodium, aspirin, and appropriate antianginal medication, is associated with improved clinical outcomes, relative to a "watchful waiting" approach based on noninvasive therapy. Thus, an early invasive approach following aggressive medical pretreatment should be the preferred strategy for patients with UCAD who present with signs of ischemia on the electrocardiogram or raised biochemical markers of myocardial damage at admission.
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PMID:Acute management--how should we intervene? 1068 38

The American College of Cardiology/American Heart Association Task Force on Practice Guidelines has published recommendations on the diagnosis and treatment of patients with known or suspected unstable angina and non-ST-segment elevation myocardial infarction. The acute ischemia pathway presented in these guidelines encompasses both an early invasive strategy and an early conservative strategy. There are now 4 randomized, controlled trials that have compared the routine early invasive strategy with the selective-invasive or ischemia-guided strategy (Thrombolysis in Myocardial Infarction [TIMI] IIIB, Veterans Affairs Non-Q-Wave Infarction Strategies in Hospital [VANQWISH], Fragmin and Fast Revascularization During Instability in Coronary Artery Disease [FRISC] II, and Treat Angina with Aggrastat and Determine Cost of Therapy with an Invasive or Conservative Strategy [TACTICS]-TIMI 18). The most relevant of these studies to current clinical practice are the FRISC II and TACTICS-TIMI 18 studies. The data from these studies indicate that ST-segment depression or elevated levels of troponin or the MB isoenzyme of creatinine kinase are markers of increased risk and that such patients would benefit from early revascularization. However, the data further suggest that aggressive antiplatelet, antithrombin, and anti-ischemic therapies are also important. Although FRISC II and TACTICS-TIMI 18 support an early invasive approach in most patients (ie, intermediate- and high-risk patients) with non-ST-segment elevation acute coronary syndromes (ACS), all 4 trials support a more conservative approach in those without electrocardiographic changes or enzyme elevations, notably the use of intensive antiplatelet, antithrombotic, and anti-ischemic therapy combined with careful clinical assessment and provocative testing. Patients then undergo catheterization and revascularization only if spontaneous angina occurs or if there is electrocardiographic, enzymatic, or other objective evidence of stress-induced myocardial ischemia. We conclude that tailoring the early initial therapy in hospital to the level of risk is essential to optimizing efficacy and clinical outcomes in this challenging, but common group of ACS patients.
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PMID:Interpreting new treatment guidelines for non-ST-segment elevation acute coronary syndromes. 1169 15

Percutaneous coronary intervention can be safely performed in patients with acute coronary syndromes (ACS), including those with non-ST-segment elevation myocardial infarction (MI), and unstable angina. Although there remains debate about whether an aggressive strategy involving early coronary arteriography and revascularization should be routinely performed in patients who present with non-ST-segment elevation MI and unstable angina, recent clinical trials suggest that an aggressive approach should be taken in both intermediate- and high-risk patients with ACS. There have been 4 clinical trials that have compared the outcomes of patients presenting with non-ST-segment elevation MI or unstable angina who were assigned to invasive or conservative strategies. The Thrombolysis in Myocardial Infarction (TIMI) IIIB trial and the Veterans Affairs Non-Q-Wave Infarction Strategies in Hospital (VANQWISH) trial failed to demonstrate a reduction in death or MI in patients assigned to an invasive approach, but it did demonstrate an important reduction in the frequency of rehospitalization. However, these studies were performed before the availability of coronary stents or the use of glycoprotein IIb/IIIa inhibitors. In contrast, the Fragmin and Fast Revascularisation During Instability in Coronary Artery Disease (FRISC) II and the Treat Angina with Aggrastat and Determine Cost of Therapy with an Invasive or Conservative Strategy (TACTICS) trials demonstrated significant improvements in the rates of death or MI in patients with non-ST-segment elevation MI or unstable angina assigned to an invasive strategy. Event reductions were greatest in patients with non-ST-segment elevation MI or unstable angina at intermediate or high risk for an adverse outcome. Understanding that these subgroups comprise approximately 75% of patients presenting with non-ST-segment elevation MI or unstable angina, we believe that an invasive approach is indicated in most patients who develop non-ST-segment elevation MI or unstable angina. Regardless of the strategy used in ACS patients, lipid-lowering therapy is necessary to reduce recurrent ischemia events at the site of plaque instability and in atherosclerotic disease remote to the target lesion.
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PMID:Use of coronary revascularization in patients with unstable and non-ST-segment elevation acute myocardial infarction. 1169 16

Is a "routine invasive" or "selective invasive" strategy the best approach for patients with non-ST-segment elevation acute coronary syndrome (ACS)? A "selective invasive" strategy incorporates ischemia-guided use of aggressive medical therapy followed by angiography and revascularization for angina or stress-induced myocardial ischemia. The "routine invasive" strategy (cardiac catheterization followed by percutaneous coronary intervention within 24 to 48 h of symptom-onset) is frequently employed, but no randomized, controlled trials have demonstrated improved clinical outcomes. Recently, the second Fragmin and fast Revascularization during InStability in Coronary artery disease (FRISC-II) and the Treat angina with Aggrastat and determine Cost of Therapy with an Invasive or Conservative Strategy-Thrombolysis in Myocardial Infarction (TACTICS TIMI-18) trials found significant reductions in death, recurrent myocardial infarction, or hospitalization for biomarker-positive ACS. Also, the third Randomized Intervention Trial of unstable Angina (RITA-3) recently reported a halving of refractory angina and reduction in the use of antianginal medication with early intervention. Early trials failed to demonstrate the superiority of the "routine invasive" approach, presumably because of fewer revascularizations, unavailability of stents, and more recent use of glycoprotein IIb/IIIa inhibitors and low-molecular-weight heparins. The FRISC-II, TACTICS TIMI-18, and RITA-3 studies indicate that higher-risk patients benefit from early revascularization, but that aggressive antiplatelet, antithrombin, and anti-ischemic therapy are also important. While all three trials support an "early invasive" approach in intermediate- and high-risk patients, other trials support a more "conservative" approach in those without electrocardiographic changes or enzyme elevations. Optimal management should incorporate both strategies.
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PMID:"Routine invasive" versus "selective invasive" approaches to non-ST-segment elevation acute coronary syndromes management in the post-stent/platelet inhibition era. 1264 49