Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002962 (angina)
 21,142 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Unstable angina is a critical phase of coronary heart disease with widely variable symptoms and prognosis. A decade ago, a classification of unstable angina based on clinical symptoms was introduced. This system was then validated by prospective clinical studies to correlate with the prognosis and was linked to angiographic and histological findings. It has been used to categorize patients in many large clinical trials. In recent years, the pathophysiological roles of platelet activation and inflammation in unstable angina have been elucidated. Subsequently, improved markers of myocardial injury, acute-phase proteins, and hemostatic markers that may be associated with clinical outcomes have been identified. Particularly, cardiac-specific troponin T and troponin I have been shown to represent the best predictors of early risk in patients with angina at rest. Accordingly, it is suggested that the original classification be extended by subclassifying one large group of unstable angina patients, ie, those with angina at rest within the past 48 hours (class IIIB), into troponin-positive (T(pos)) and troponin-negative (T(neg)) patients. The 30-days risk for death and myocardial infarction is considered to be up to 20% in class IIIB-T(pos) but <2% in class IIIB-T(neg) patients. Initial results suggest that troponins may function as surrogate markers for thrombus formation and can effectively guide therapy with glycoprotein IIb/IIIa antagonists or low-molecular-weight heparins. These observations provide additional impetus for adding the measurement of these markers to the clinical classification and represent a novel concept of treating these high-risk patients.
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PMID:A classification of unstable angina revisited. 1088 Apr 24

We sought to investigate the relation between platelet activation and the angiographic evidence of ruptured plaque in patients presenting with unstable and stable angina pectoris. We prospectively enrolled 25 consecutive patients (5 women and 20 men, mean age 62 +/- 3 years), 17 with unstable angina and 8 with stable angina. Systemic venous blood samples were collected within 4 to 6 hours of admission for flow cytometry analysis. Activation-dependent epitope CD63 and glycoprotein IIb/IIIa on the platelet membrane were assayed. Fibrinogen levels were also measured. All patients with unstable angina underwent cardiac catheterization and had angiographic evidence of ruptured plaque. Of the patients with stable angina, 5 underwent coronary angiography with smooth noncomplex lesions and 3 had negative technetium-99m sestamibi stress tests. Patients with unstable angina were characterized by 39% higher levels of fibrinogen than patients with stable angina (423 +/- 304 vs 304 +/- 51 mg/dl, p = 0.004). The percentage of platelets positive for the activation-dependent epitope CD63 was 5 times higher in patients with unstable than stable angina (14.6 +/- 5.6% vs 2.75 +/- 1.6%, p = 0.0026). They also had a 15% higher expression of their glycoprotein IIb/IIIa (517 +/- 79 vs 449 +/- 50 mean fluorescence intensity, p = 0.038). Thus, this study establishes a direct relation between the morphology of ruptured plaque and platelet activation in patients with unstable angina. This may allow for further risk stratification. Patients with unstable complex lesions had a fivefold higher expression of the platelet activation epitope CD63 than patients with stable angina. Furthermore, they had 15% more glycoprotein IIb/IIIa aggregation sites expressed on their platelet membrane, thus indicating an intense thrombogenic potential.
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PMID:Comparison of platelet activation in unstable and stable angina pectoris and correlation with coronary angiographic findings. 1102 97

Glycoprotein IIb-IIIa receptor inhibitors are the newest anti-platelets drugs currently used in patients with coronary artery disease. We examined mechanisms of their action and different pharmacokinetic and pharmacodynamic characteristics of the four glycoprotein IIb-IIIa antagonists evaluated in randomized, controlled and multicenter trials. We reviewed results of these trials in the settings of percutaneous revascularizations procedures or unstable coronary syndromes. Platelet glycoprotein IIb-IIIa receptor inhibitors reduced incidence of cardiac death and myocardial infarction during the short- and midterm, and benefit was greater in: a) patients undergoing coronary angioplasty with or without stent implantation, particularly in the presence of unstable angina, diabetes or complex and diffuse coronary artery disease; b) as a direct therapy of unstable coronary syndromes, particularly in patients with refractory angina, diabetes and elevated Troponin; more recently they have been used as adjuvant therapy in acute myocardial infarction. Infusion of these drugs was not associated with higher rates of major bleedings.
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PMID:[Platelet glycoprotein IIB-IIIA receptor inhibitors in patients with ischemic heart disease]. 1110 81

Patients with acute myocardial infarction (AMI) who do not receive early reperfusion therapy are at high risk of reinfarction or death, and the efficacy and safety of antithrombotic therapy in this group of patients has not been evaluated. Enoxaparin is a low-molecular-weight heparin (LMWH) that has previously been shown to reduce the incidence of ischemic events in patients with unstable angina or non-Q-wave MI. The principal aims of the TETAMI study are to investigate the efficacy and safety of treatment with enoxaparin or tirofiban (a glycoprotein IIb/IIIa receptor antagonist) alone or in combination for 2 to 8 days in patients with AMI who are not eligible for early reperfusion therapy. In this 2 by 2 factorial design study approximately 900 patients will be randomly assigned, in a blinded manner, to one of four treatments: enoxaparin alone, enoxaparin plus tirofiban, unfractionated heparin (UFH), or UFH plus tirofiban, with appropriate matched placebos. The primary end point is the composite of death, recurrent AMI, and recurrent angina, analyzed at 30 days after AMI. The design and methods of the TETAMI study are described in this article.
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PMID:The TETAMI trial: the safety and efficacy of subcutaneous enoxaparin versus intravenous unfractionated heparin and of tirofiban versus placebo in the treatment of acute myocardial infarction for patients not thrombolyzed: methods and design. 1112 44

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

The treatment of angina is changing, with many new agents being added to those existing agents that have been used for many years. New data regarding the use of glycoprotein IIb/IIIa inhibitors now exist and low molecular weight heparins are used more frequently with greater efficacy than unfractionated heparin. New thrombin inhibitors are also receiving a fresh look. An expert panel has recently published guidelines for the treatment of unstable angina.
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PMID:New approaches to the pharmacological treatment of angina. 1171 89

Aspirin (acetylsalicylic acid) should be administered to patients on day 1 of an acute myocardial infarction (MI) and continued indefinitely. Early intravenous beta-blockade should be used during acute MI. beta-blockers should be continued indefinitely. Angiotensin-converting enzyme (ACE) inhibitors should be used in patients with acute MI with ST-segment elevation in two or more anterior precordial leads. ACE inhibitors should be used during and after acute MI in patients with chronic heart failure (CHF) or with a left ventricular ejection fraction < or =40%. There are no class I indications for using calcium channel antagonists during and after acute MI. Intravenous heparin should be used in patients with acute MI undergoing coronary revascularisation and in patients at high risk for systemic embolisation. Enoxaparin should be used in patients with non-Q-wave MI. Thrombolytic therapy should be considered in patients with acute MI with ST-segment elevation in contiguous leads of a 12-lead electrocardiogram or with left bundle branch block. Platelet glycoprotein IIb/IIIa inhibitors should be administered intravenously as an adjunct to heparin and aspirin in patients with non-Q-wave MI. Intravenous nitroglycerin should be used: (i) for the first 24 to 48 hours in patients with acute MI and CHF, large anterior MI, persistent ischaemia or hypertension; and (ii) continued beyond 48 hours in patients with recurrent angina pectoris or persistent pulmonary congestion. Long-acting nitrates should be given after MI, along with beta-blockers, to patients with angina pectoris. There are no class I indications for using intravenous magnesium during acute MI. The routine use of antiarrhythmic drugs other than beta-blockers during and after acute MI is not recommended.
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PMID:Drug treatment of elderly patients with acute myocardial infarction: practical recommendations. 1177 21

In a large phase III study of patients with unstable angina treated with percutaneous transluminal coronary angioplasty (PTCA), the thrombin-specific anticoagulant bivalirudin produced relative risk reductions of 22% (p = 0.039) for ischemic complications and 62% (p < 0.001) for bleeding complications compared with heparin. Subsequent reports have shown that between-treatment differences favoring fewer complications with bivalirudin also extend to high-risk patients. Early heparinization promotes heparin resistance and decreases activated clotting time achieved during PTCA. These effects are relevant to patients with postinfarction angina, which is associated with a greater likelihood of early vessel closure and procedural failure. In 1006 patients with one or both of these risk factors, bivalirudin significantly reduced combined ischemic and bleeding complications compared with heparin (8.6% vs 18%, p < 0.001). Treatment separations favoring bivalirudin increased with risk, suggesting decreased heparin effectiveness in patients at heightened risk. Findings in three additional risk groups-women, the elderly, and patients not receiving glycoprotein IIb/IIIa inhibitors-also showed fewer complications with bivalirudin therapy. Preliminary data suggest that bivalirudin can be combined safely with glycoprotein IIb/Illa antagonists in percutaneous coronary intervention (PCI), including PTCA. An ongoing trial is aimed at determining the efficacy and safety of heparin with planned glycoprotein IIb/IIIa therapy versus bivalirudin with provisional glycoprotein IIb/IIIa therapy. The use of bivalirudin in patients with heparin-induced thrombocytopenia also is being evaluated after favorable findings in early compassionate-use studies. The fact that between-treatment differences favoring bivalirudin were especially outstanding among the high-risk patients considered in this review reinforces the impression that bivalirudin is a promising and unprecedented alternative to heparin in PCI.
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PMID:Bivalirudin administration during percutaneous coronary intervention: emphasis on high-risk patients. 1206 68

Recent randomized clinical trials with intravenous glycoprotein IIb/IIIa inhibition have provided unanticipated results, thereby questioning their role as empirical medical management for acute coronary syndromes. The lack of benefit with abciximab observed in Global Utilization of Strategies to Open Occluded Coronary Arteries IV is somewhat inconsistent with the benefits seen with this agent in coronary intervention, and the benefits of an early invasive approach incorporating tirofiban seen within Treat Angina with Aggrastat and determine Cost of Therapy with an Invasive or Conservative Strategy Thrombolysis in Myocardial Infraction 18. Additionally, a direct 'head-to-head' comparative study of abciximab and tirofiban within the setting of percutaneous coronary intervention demonstrates clinically relevant superiority with abciximab with respect to 30-day outcomes. in the setting of coronary instability and mechanical plaque disruption is more complex than initially perceived. Hence, although an abundance of evidence details the efficacy of these agents, their optimal clinical application remains somewhat challenging in light of these recent data. However, within the context of previous trial experience, the current evidence highlights several key aspects of glycoprotein IIb/IIIa inhibitor therapy that may be associated with improved patient outcomes. In particular, these trials indicate: (i) the importance of selecting high-risk patients in whom substantial clinical benefit is evident, (ii) the incorporation of these agents into an early invasive strategy, thereby matching the timing of vascular injury with maximal platelet inhibition and (iii) optimal dosing to achieve the high levels of platelet inhibition that appear to be required for efficacy with these agents.
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PMID:Optimizing glycoprotein IIb/IIIa inhibition: lessons from recent randomized controlled trials. 1208 54

Acute coronary syndrome (ACS) represents a heterogenous spectrum of conditions. The Global Registry of Acute Coronary Events (GRACE) describes the epidemiology, management, and outcomes of patients with ACS. Data were collected from 11,543 patients enrolled in 14 countries. Of these patients, 30% had ST-segment elevation myocardial infarction (STEMI), 25% had non-ST-segment elevation myocardial infarction (NSTEMI), 38% had unstable angina pectoris, and 7% had other cardiac or noncardiac diagnoses. Over half of these patients (53%) were >/=65 years old. Reperfusion therapy was used in 62% of patients with STEMI. Percutaneous coronary intervention was performed in 40% of these subjects during the index admission. Intravenous glycoprotein IIb/IIIa blockers were used in 23%, 20%, and 7% of patients with STEMI, NSTEMI, and unstable angina, respectively (STEMI vs NSTEMI, p = 0.0018, and for either group vs unstable angina, p <0.001). Coronary artery bypass grafting was performed in 4%, 10%, and 5% of patients, respectively (p <0.0001). Hospital case fatality rates were markedly different among patients with STEMI, NSTEMI, and unstable angina (7%, 6%, and 3%, respectively; STEMI vs NSTEMI, p = 0.0459, and for either group vs unstable angina, p <0.001). Congestive heart failure complicated the hospital course in 18%, 18%, and 10% of the patients, respectively (p <0.0001), and recurrent angina with ST-segment changes occurred before discharge in 10%, 10%, and 9% of patients, respectively (p = 0.2644). GRACE provides a detailed and comprehensive global description of the spectrum of patients with ACS.
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PMID:Baseline characteristics, management practices, and in-hospital outcomes of patients hospitalized with acute coronary syndromes in the Global Registry of Acute Coronary Events (GRACE). 1216 Dec 22


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