Myocardial infarction syndromes

Fondaparinux, the factor Xa-binding pentasaccharide (Arixtra, MW 1,728 Da), is prepared synthetically, unlike UFH, LMWH and danaparoid, which are obtained from animal sources. Despite only inactivating free factor Xa, clinical trials indicate that fondaparinux is an effective antithrombotic agent, both for venous thromboembolism prophylaxis and treatment, as well as for acute coronary syndrome and ST elevation myocardial infarction [4]. 

GPIIb/IIIa antagonists have to be administered parenterally. They are currently used prophylactically during intracoronary interventions such as percutaneous transluminal revascularization with balloon angioplasty or intracoronary stenting, as well as to treat acute coronary syndromes like unstable angina and acute myocardial infarction. The main complications... 

Acute coronary syndromes most often result from a physical disruption of the fibrous cap, either frank cap fracture or superficial endothelial erosion, allowing the blood to make contact with the thrombogenic material in the lipid core or the subendothelial region of the intima. This contact initiates the formation of a thrombus, which can lead to a sudden and dramatic blockade of blood flow through the affected artery. If the thrombus is nonocclusive or transient, it may either be clinically silent or manifest as symptoms characteristic of unstable angina. Importantly, if collateral vessels have previously formed, for example, due to chronic ischemia produced by multi vessel disease, even total occlusion of one coronary artery may not lead to an acute myocardial infarction. 

A laxative is most often prescribed for the short-term relief or prevention of constipation. Certain stimulant, emollient, and saline laxatives are used to evacuate the colon for rectal and bowel examinations. Fecal softeners or mineral oil are used prophylactically in patients who should not strain during defecation, such as after anorectal surgery or a myocardial infarction. Psyllium may be used in patients with irritable bowel syndrome and diverticular disease. Fblycarbophil may be prescribed for constipation or diarrhea associated with irritable bowel syndrome and diverticulosis. Mineral oil is... 

Age >40 yr, previous venous thromboembolism, chronic heart failure, acute respiratory failure, recent major surgery (within 2 wk), confined air/ground travel (>6 h duration within 1 wk of admission), inflammatory bowel disease, myocardial infarction, nephrotic syndrome, and ischemic stroke... 

O Ischemic heart disease results from an imbalance between myocardial oxygen demand and oxygen supply that is most often due to coronary atherosclerosis. Common clinical manifestations of ischemic heart disease include chronic stable angina and the acute coronary syndromes of unstable angina, non-ST-segment elevation myocardial infarction, and ST-segment elevation myocardial infarction. 

List key electrocardiographic and clinical features identifying a patient with non-ST-segment elevation acute coronary syndrome who is at high risk of myocardial infarction or death. 

Acute myocardial infarction Angiopathy Aortic aneurysm Aortic balloon assist devices Giant hemangiomas Peripheral vascular disease Postcardiac arrest Prosthetic devices Raynaud s syndrome Infectious Arbovirus Aspergillus Candida albicans Cytomegalovirus Ebola virus... 

Acute coronary syndromes Ischemic chest discomfort at rest, most often accompanied by ST-segment elevation, ST-segment depression, or T-wave inversion on the 12-lead electrocardiogram. Furthermore, it is caused by plaque rupture and partial or complete occlusion of the coronary artery by thrombus. Acute coronary syndromes include myocardial infarction and unstable angina. Former terms used to describe types of acute coronary syndromes include Q-wave myocardial infarction, non-Q-wave myocardial infarction, and unstable angina. 

A specific immunoassay for measuring two-chain factor VIIa levels in plasma has been developed to identify activation of factor VII in patients with acute coronary syndromes suchs as myocardial infarction and unstable angina (12). Because regulation of factor VIIa is believed to be mediated by tissue factor pathway inhibitor (TFPI), its measurement is also useful in assessing thombotic and cardio-vasular disorders. Because TFPI is released by heparin, its measurement is also useful in assessing the efficacy of heparin and endothelial cell function (93). 

Suggested Alternatives for Differential Diagnosis Acute respiratory distress syndrome, plague, congestive heart failure and pulmonary edema, HIV infection and AIDS, pneumonia, shock, phosgene, influenza, tularemia, phosphine toxicity, anthrax, silent myocardial infarction, and salicylate toxicity with pulmonary edema. 

FIGURE 5-2. Biochemical markers in suspected acute coronary syndrome. (AMI, acute myocardial infarction CK-MB, creatine kinase myocardial band Ml, myocardial infarction.)... 

Amiodarone (11), a benzofuran derivative, was initially developed as a coronary vasodilator in the early 1960 s [11,12]. Several years later, the efficacy of the compound as an antiarrhythmic agent began to be exploited. The first clinical trials with amiodarone were reported in 1974 [13]. Amiodarone was effective in controlling the tachyarrhythmias of eleven patients with Wolff-Parkinson-White syndrome. Since that time the compound has been studied extensively [14,15]. Recently, in the Canadian Amiodarone Myocardial Infarction Arrhythmia Trial (CAMIAT), amiodarone was shown to reduce mortality during a mean 18 month period following myocardial infarction (13.8% deaths in placebo group vs. 2.1 % deaths in the treatment group) [16]. 

Fig. 5.3 Results of TACTICS TIMI 18. Primary end point of death, non-fatal myocardial infarction, and rehospitalization for acute coronary syndrome at 6 months based on baseline patient characteristics ( 2001 Massachusetts Medical Society)...

Drug therapy of acute coronary syndromes including unstable angina and non-Q-wave myocardial infarction includes use of aspirin, heparin and anti-ischaemic drugs and is similar in older patients to other age groups. Activation of platelet thromboxane production in the coronary circulation has been demonstrated in unstable angina. The risk of myocardial infarction or death is reduced by approximately 50% by early aspirin therapy in recommended doses of 160-325 mg per day and continued... 

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