Heart attack infarction

High blood pressure damages the blood vessels, and can lead to stroke or heart attacks (infarctions), as well as heart and kidney failure (Fig. 5.6). 

There is a close correlation between myocardial infarctions and tachyarrhythmias, illustrated by the presence of complex ventricular arrhythmias among heart attack victims which are estimated to affect one-third of the survivors each year. Frequendy, the immediate cause of sudden death is ventricular fibrillation, an extreme arrhythmia that is difficult to detect or treat. In the majority of cases, victims have no prior indication of coronary heart disease. 

Other Cardiovascular Agents Effecting Atherosclerosis. A large amount of clinical data is available concerning semm Upid profiles in patients subjected to dmg therapy for other cardiovascular diseases. Atheroma, for example, may be the underlying cause of hypertension and myocardial infarction. There are on the order of 1.5 million heart attacks pet year in the United States (155). 

Indications for treatment with streptokinase include acute occlusion of arteries, deep vein thrombosis, and pulmonary embolism. Streptokinase therapy in coronary thrombosis, which is the usual cause of myocardial infarction (54,71,72), has proved to be valuable. In this frequently fatal condition, the enzyme is adrninistered intravenously at a dose of 1.5 million units over 60 min, or given by intracoronary infusion at a 20,000- to 50,000-unit bolus dose followed by 2000 to 4000 units/min for 60 min therapy must be instituted as soon as practicable after the diagnosis of heart attack is made. For deep vein thrombosis, pulmonary embolism, or arterial occlusion, streptokinase is infused at a loading dose of 250,000 units given over 30 min, followed by a maintenance dose of 100,000 units over a 60-min period. 

These drugp are contraindicated in patients with known hypersensitivity to the drug or to any constituents of the drug, after a recent myocardial infarction (heart attack), or in patients with thyrotoxicosis. When hypothyroidism is a cause or contributing factor to a myocardial infarction or heart disease, the physician may prescribe small doses of thyroid hormone... 

MI myocardial infarction (heart attack) RF rheumatoid factor... 

Another vasoactive substance produced by the endothelium is thromboxane A2 (TxA2). Normally, small amounts of TxA2 are released continuously however, increased synthesis appears to be associated with some cardiac diseases. Synthesized from arachidonic acid, a plasma membrane phospholipid, TxA2 is a potent vasoconstrictor. Furthermore, this substance stimulates platelet aggregation, suggesting that it plays a role in thrombotic events such as myocardial infarction (heart attack). Nonsteroidal anti-inflammatory drugs such as aspirin and ibuprofen block formation of TxA2 and reduce formation of blood clots. 

Various antibody preparations have been developed that facilitate imaging of vascular-related conditions, including myocardial infarction, deep vein thrombosis and atherosclerosis. Anti-myosin monoclonal antibody fragments (Fab) labelled with mIn, for example, have been used for imaging purposes in conjunction with a planar gamma camera. The antibody displays specificity for intracellular cardiac myosin, which is exposed only upon death of heart muscle tissue induced by a myocardial infarction (heart attack). 

Deliver Reliable, Evidence-Based Care for Acute Myocardial Infarction... to prevent deaths from heart attack... 

Cardiovascular disease Cardiomyopathy Congestive heart failure Myocardial infarction (heart attack)... 

Metoprolol is nsed in moderate hypertension, serions conditions of myocardial infarction, for preventing death of cardiovascular tissue, in angina, tachycardia, extrasystole, and for secondary prophylaxis after a heart attack. The most common synonyms are lopresor, betaloc, and others. 

Goldberg RJ, Zevallos JC, Yarzebski J, et al. Prognosis of acute myocardial infarction complicated by complete heart block (the Worcester Heart Attack Study). Am. J. Cardiol. 1992 69 1135-41. 

These potential benefits are balanced by a slightly increased risk of gallbladder disease, hypertension, myocardial infarction, cerebral infarction, and pulmonary embolism. The increased risk of stroke and heart attack associated with the pill is accentuated when compounded by other risk factors, including smoking, migraine headaches, and advancing age. Indeed, convincing data support an upper age limit of 35 years for oral contraceptive use by women who smoke. 

Indications The management of acute myocardial infarction (AMI) in adults for the improvement of ventricular function following a heart attack, the reduction of the incidence of congestive heartfailure,andthe reduction of mortality associated with AMI... 

Overview analyses have shown that low-dose aspirin reduces the secondary incidence of heart attack and stroke by about 25%. However, it elevates the low risk of serious gastrointestinal bleeding about twofold over placebo. Low-dose aspirin also reduces the incidence of first myocardial infarction. However, in this case, the benefit versus risk of gastrointestinal bleeding is less clear. The effects of aspirin on platelet function are discussed in greater detail in Chapter 34. 

Most drug discovery efforts focus on thrombin inhibition as a means to prevent the serious consequences of thrombus formation in myocardial infarction and stroke. Thrombin inhibitors may also prevent clot formation in patients prone to deep vein thrombosis or repeat heart attack. In combination with thrombus dissolution therapies, thrombin inhibitors may decrease the incidence of reocclusion due, in part, to the release of active clot-bound thrombin. 

The cardiac output or flow of blood normally is so rapid that the distribution of a drug or poison throughout the body is complete within a short period of time. An entire 6 liter supply of blood is pumped through the body at the rate of about once per minute. Some organs and tissues are more highly perfused with blood than others, such as the brain, heart, liver, and kidneys. Adipose (fat) tissue is not as richly endowed. Should a person be in shock or have suffered a myocardial infarction (heart attack), however, the cardiac output can be sharply diminished and a route of drug administration normally used may be circumvented because of poor... 

These differences in the isozyme content of tissues can be used to assess the timing and extent of heart damage due to myocardial infarction (heart attack). Damage to heart tissue results in the... 

Ischemic heart disease is the leading cause of death in the United States today (American Heart Association, 2001). In 1998, over 450,000 deaths were attributable to ischemic heart disease. This year over 1.1 million citizens will have a new or recurrent myocardial infarction. One of the consequences of non-fatal myocardial infarction is congestive heart failure (CHF), afflicting 22% of men and 46% of women surviving heart attacks over the subsequent five years. Currently, there are over 4.7 million Americans living with CHF, and these patients have a five year mortality of 50%. The mainstay of therapy for ischemic heart disease is revascularization. Nearly 2,000,000 cardiac catheterizations and 553,000 coronary artery bypass surgical procedures are performed annually (American Heart Association, 2001). 

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