Herz
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Review Comparative Study
[Acute coronary syndromes: an update. I. Pathogenesis and drug therapy].
Unstable angina accounts for more than one million hospital admissions annually. 6-8% of patients with this condition have non-fatal myocardial infarction or die within the first year after diagnosis. Recently, the term "acute coronary syndromes" has been used to describe the spectrum of conditions that includes unstable angina, non-Q-wave myocardial infarction (which generally presents without ST-segment elevation), and Q-wave myocardial infarction (which generally presents with ST-segment elevation). ⋯ Multiple huge clinical trials confirmed that aspirin reduces the risk of death from cardiac causes and fatal and non-fatal myocardial infarction by about 50-70% in patients presenting with unstable angina. Ticlopidine may be substituted for aspirin in patients with hypersensitivity to aspirin or gastrointestinal intolerance. Clopidogrel acts similarly to ticlopidin but has fewer side effects than ticlopidine and has not been reported to cause neutropenia. High-risk patients with refractory unstable angina and elevated troponin levels may have substantial benefit of glycoptotein (GP) IIb/IIIa inhibition. Current practice guidelines support the use of the combination of unfractionated heparin and aspirin for the treatment of unstable angina. Clinical studies have demonstrated that the incidence of the composite end point of death, myocardial infarction, or recurrent angina was lower with enoxaparin than with unfractionated heparin. Beta-blockers, nitrates, and calcium-channel blockers are useful for antiischemic therapy in patients with acute coronary syndromes.
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Review Comparative Study
[Acute coronary syndromes: an update. II. Coronary revascularization and risk stratification].
CORONARY REVASCULARIZATION: PTCA in patients with refractory unstable angina is associated with a substantial risk of the following complications: death, myocardial infarction, need for emergency surgery, and restenosis. The introduction of intracoronary stents, however, has improved both short-term and long-term outcomes. The newer adjunctive pharmacologic therapies enhance even further the benefits associated with the use of stents. The decision regarding the specific revascularization procedure to be used (e.g., CABG, PTCA, stent placement, or atherectomy) is based on the coronary anatomy, the left ventricular function, the experience of the medical and surgical personnel, the presence or absence of coexisting illnesses, and the preferences of both the patient and the physician. ⋯ Among patients with unstable angina or non-Q-wave myocardial infarction, there is an increased risk of death within 6 weeks in those with elevated troponin I levels and the risk of death continues to increase as the troponin level increases. Reversible ST segment depression is associated with an increase by a factor of 3-6 in the likelihood of death, myocardial infarction, ischemia at rest, or provocable ischemia during a test to stratify risk. Exercise or pharmacologic stress testing provides important information about a patient's risk. Although the conditions of the majority of patients with unstable angina will stabilize with effective antiischemic medications, approximately 50-60% of such patients will require coronary angiography and revascularization because of the "failure" of medical therapy. High-risk patients are those who have had angina at rest, prolonged angina, or persistent angina with dynamic ST segment changes or hemodynamic instability, and they urgently require simultaneous invasive evaluation and treatment. Medical therapy should be adjusted rapidly to relieve manifestations of ischemia and should include antiplatelet therapy (aspirin, or ticlopidine or clopidogrel if aspirin is contraindicated), antithrombotic therapy (unfractionated heparin or low-molecular-weight heparin), beta-blockers, nitrates, and possibly calcium-channel blockers. Early administration of glycoprotein IIb/IIIa inhibitors may be particularly important, especially in high-risk patients with positive troponin tests or those in whom implantation of coronary stents is anticipated.
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Cardiac tamponade is a life-threatening condition. Accurate diagnosis and prompt intervention are necessary to prevent adverse outcomes. Clinical features of tamponade such as pulsus paradoxus, tachycardia, elevated jugular venous pressure, and hypotension are important clues to the diagnosis, but are non-specific. ⋯ Decisions regarding treatment must take into account the clinical presentation and echocardiographic findings. Echocardiographically-guided pericardiocentesis with catheter drainage is the primary treatment strategy of choice for most large or hemodynamically significant effusions. In contemporary clinical practice, echocardiography is the gold standard for diagnosis of tamponade and is essential for directing treatment.
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The formation of new blood vessel is essential for a variety of physiological processes like embryogenesis and the female reproduction as well as wound healing and neovascularization of ischemic tissue. Major progress in understanding the underlying mechanisms regulating blood vessel growth has offered novel therapeutic options in the treatment of a variety of diseases including ischemic cardiovascular disorders. Vasculogenesis and angiogenesis are the mechanisms responsible for the development of the blood vessels. ⋯ Granulocyte macrophage colony stimulating factor (GM-CSF) and vascular endothelial growth factor (VEGF) mobilize EPC from the bone marrow into the peripheral circulation. While their endogenous contribution to postnatal neovascularization needs to be documented, the iatrogenic expansion and mobilization of EPC might represent an effective means to augment the resident population of endothelial cells (ECs). This kind of cell therapy for tissue regeneration in ischemic cardiovascular diseases opens a novel and challenging clinical option besides or in addition to the use of growth factors in gene therapy.
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Cardiogenic shock is a state of inadequate tissue perfusion due to cardiac dysfunction, which is most commonly caused by acute myocardial infarction. The pathophysiology of cardiogenic shock is characterized by a downward spiral: ischemia causes myocardial dysfunction, which, in turn, augments the ischemic damage and the energetical imbalance. With conservative therapy, mortality rates for patients with cardiogenic shock are frustratingly high reaching more than 80%. ⋯ Using 9.5-F catheters, a long duration of counterpulsation emerged as the most significant factor associated with complications. In our hospital, those patients with 9.5-F catheters in whom counterpulsation did not exceed 48 hours had a low complication rate of 3.9%. The Hemopump is a catheter-mounted transvalvular left ventricular assist device intended for surgical placement via the femoral artery (Figures 6 and 7). (ABSTRACT TRUNCATED)