unstable angina

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 [an-ji´nah, an´jĭ-nah]
spasmodic, choking, or suffocative pain; now used almost exclusively to denote angina pectoris. adj., adj an´ginal.
agranulocytic angina agranulocytosis.
crescendo angina old term for unstable angina.
angina cru´ris intermittent claudication.
herpes angina (angina herpe´tica) herpangina.
intestinal angina generalized cramping abdominal pain occurring shortly after a meal and persisting for one to three hours, due to ischemia of the smooth muscle of the bowel.
Ludwig's angina see ludwig's angina.
angina pec´toris acute pain in the chest resulting from myocardial ischemia (decreased blood supply to the heart muscle); the condition has also been called cardiac pain of effort and emotion because the pain is brought on by physical activity or emotional stress that places an added burden on the heart and increases the need for blood being supplied to the myocardium. Some patients can predict the kinds of events that will precipitate an attack while others are unaware of any relationship between onset of an attack and any particular situation in their lives.

Angina pectoris occurs more frequently in men than in women, and in older persons than in younger persons. It is not a disease entity but a symptom of an underlying disease process involving the arteries that supply blood to the heart muscle. About 90 per cent of all cases can be attributed to coronary atherosclerosis. Studies have shown that at least one of the three major coronary arteries usually is stenosed before angina develops. In most cases, all of the major coronary arteries are involved.

Angina pectoris also can result from stenosis of the aorta, pulmonary stenosis and ventricular hypertrophy, or connective tissue disorders such as systemic lupus erythematosus and periarteritis nodosa that affect the smaller coronary arteries.
Symptoms. The chief symptom is chest pain, usually unmistakably distinguished by the patient as different from other types of pain such as that caused by indigestion. It is generally described as a feeling of tightness, strangling, heaviness, or suffocation and is usually concentrated on the left side, beginning just under the sternum; it sometimes radiates to the neck, throat, and lower jaw and down the left arm, and occasionally to the stomach, back, or across to the right side of the chest. The pain seldom lasts more than 15 minutes and is usually relieved by rest and relaxation or by administration of nitrates. If it is not relieved in 10 to 15 minutes, the physician should be notified and the patient taken to a cardiac care unit. The decreased blood supply to the heart makes it especially vulnerable to arrhythmias and myocardial infarction, which are the cause of death in about one third of all cases.

Coronary arteriography and ventriculography are valuable in determining the prognosis for angina pectoris. The mortality rate for patients having a narrowing of all three main coronary arteries is higher than for those who have only one vessel involved. Severity of pain is not a good prognostic indicator; some patients with severe discomfort live for many years, while others with mild symptoms die suddenly. An enlarged heart, a third heart sound, ECG abnormalities at rest, and hypertension are all indicative of a poor prognosis.
Treatment and Patient Care. Relief from pain by rest and prevention of attacks by avoiding situations which precipitate them are the first steps in the care of the patient with angina. In most cases patients are eager to learn about the disease process causing the pain and want to know how they can participate in control of their attacks. However, compliance with the prescribed regimen usually requires a change in life style and the breaking of some lifelong habits. The known risk factors for coronary heart disease are explained to the patient, and a regimen designed to avoid further damage to the arteries is prescribed.

Organic nitrates may be administered orally or sublingually for relief from anginal pain. They act by dilating the arteries and may be used to treat acute attacks, for long-term prophylaxis and management, or for prophylaxis in situations likely to provoke an attack. Commonly used nitrates are erythrityl tetranitrate, isosorbide dinitrate, and nitroglycerin.

Beta-adrenergic blocking agents, such as propranolol, are used to treat patients who do not respond to weight control and treatment with vasodilators and whose angina significantly limits their activities. These agents decrease the heart rate, blood pressure, and myocardial oxygen consumption and increase the patient's exercise tolerance.

The calcium channel blocking agents (nifedipine, verapamil, diltiazem, and others) are drugs that are particularly beneficial in relieving pain in patients whose angina is the result of coronary artery spasm or constriction. They act by selectively inhibiting the transport of calcium across the cell membrane of myocardial cells and also by reducing myocardial oxygen utilization. Patients most likely to obtain dramatic relief from drugs of this kind are those who experience chest pain while resting or sleeping, upon exposure to cold, or during emotional stress.

Surgical procedures involving arterial bypass and angioplasty have become fairly common as a form of treatment of certain types of ischemic heart disease and resulting angina pectoris. The surgical procedures attempt to bypass the diseased portion of the coronary artery by suturing a vein graft or the internal mammary artery from the aorta to one or more coronary arteries beyond the area of obstruction. In most instances the graft is obtained from the patient's saphenous vein. Angioplasty reestablishes patency of the vessels; in most cases, it is now accompanied by insertion of a stent to help prevent restenosis.

An attitude of calmness and efficiency is most important when caring for a person suffering from an attack of angina pectoris. The pain produces emotional reactions and the strongest of these is fear. Most of these patients know that their pain is resulting from an insufficient supply of oxygen to the heart and they frequently have a feeling of impending death. It usually helps to raise the patient to a sitting position so that breathing is less difficult. The prompt administration of nitroglycerin or the specific drug ordered by the physician should shorten the attack and relieve pain. Above all, the calm presence of someone who knows how to care for them can do much to reassure patients and help them relax, thus lessening the severity of the attack.
preinfarction angina angina that lasts longer than 15 minutes; it is a symptom of worsening cardiac ischemia.
Prinzmetal's angina a variant of angina pectoris in which the attacks occur during rest, exercise capacity is well preserved, and attacks are associated electrocardiographically with elevation of the ST segment. It is cyclic in nature and is believed to be caused by coronary artery spasm.
stable angina chest pain of cardiac origin that has not changed in character, frequency, intensity, or duration for 60 days.
unstable angina chest pain of cardiac origin that is variable, usually increasing in frequency and intensity and with irregular timing.
variant angina Prinzmetal's angina.
Vincent's angina see vincent's angina.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

un·sta·ble an·gi·na

1. angina pectoris characterized by pain or sensation of pressure in the chest which is of coronary origin occurring in response to progressively less exercise (or none) or fewer other stimuli than ordinarily required to produce angina; often leading to myocardial infarction, if untreated.
2. angina that has not achieved a constant or reproducible pattern in 30 or 60 days.
Farlex Partner Medical Dictionary © Farlex 2012

unstable angina

Angina pectoris characterized by pain of coronary origin that occurs in response to less exercise or other stimuli than usually required to produce pain.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.

unstable angina

Accelerating angina, new-onset angina, progressive angina Cardiology A spectrum of Sx of ischemic heart disease, intermediate in severity between stable angina pectoris–intense chest pain and acute MI–crushing chest pain; UA is a subacute < 6 months in duration–state with ↑ risk of MI and sudden death Risk factors ♂, cigarette smoking, ↑ cholesterol–in particular, ↑ LDL-C and/or ↓ HDL-C, HTN, DM, family Hx of CAD < age 55, sedentary lifestyle, > 30% ideal body weight, sudden overwhelming stress Clinical Chest pain at rest, or ↑ in severity, frequency, or duration of chest pain at lower levels of activity DiffDx MI, DM, HTN, myxedema, peripheral vascular disease, heart valve disease, cardiomyopathy, ASHD Management Antianginals–eg, nitrates, beta-blockers, CCBs, aspirin, IV heparin. See Angina pectoris, ATACS, FRISC, HASI, Myocardial infarction, RISC, Silent ischemia, TAUSA, TIMI-3A, TIMI-3B, TIMI-7, UNASEM. Cf Prinzmetal's angina.
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.

a·cute cor·o·nar·y syn·drome

(ACS) (ă-kyūt' kōr'ŏ-nar-ē sin'drōm)
A general term for clinical syndromes due to reduction of blood flow in coronary arteries (e.g., unstable angina, acute myocardial infarction).
Synonym(s): acute myocardial infarction, preinfarction angina, unstable angina.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012

unstable angina

A severe and dangerous form of ANGINA PECTORIS due to breakdown of atherosclerotic plaque in the coronary arteries and the formation of blood clot (thrombosis). There may also be coronary artery spasm from products derived from blood platelets. Pain becomes more frequent and prolonged and may occur at rest. The accurate predictability of pain in terms of its relation to a given amount of exertion is lost. The risk of a heart attack is high.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005

a·cute cor·o·nar·y syn·drome

(ACS) (ă-kyūt' kōr'ŏ-nar-ē sin'drōm)
A general term for clinical syndromes due to reduction of blood flow in coronary arteries.
Synonym(s): preinfarction angina, unstable angina.
Medical Dictionary for the Dental Professions © Farlex 2012
References in periodicals archive ?
Altogether the investigated cases were divided into ten combinations of DRGs, and the type of surgery was chosen as the main classification node, which was correlated with the practical situation of patients with unstable angina pectoris in China.
The above table depicts that mean serum ferritin levels in Acute Myocardial Infarction, Unstable Angina and Controls were 81.83 [+ or -] 97.46, 90.24 [+ or -] 41.88 and 165.13 [+ or -] 104.17.
PCI volume in AMI patients rebounded to pre-COURAGE levels, whereas volume in patients with diagnoses of unstable angina or stable angina and other diagnoses remained below 2006 levels.
Though Huxin Formula failed to show superiority in primary and secondary outcomes, it has benefits in improving the quality of life in patients with unstable angina.
Platelet activation in unstable angina depending on troponin I concentration.
The sole exception to this approach might possibly be the small number of patients who initially presented with both proximal LAD disease and either class III or IV stable angina or unstable angina, because eventually over 5 years 71% of these patients underwent revascularization.
The female patients who had heart attacks or unstable angina, conditions known collectively as acute coronary syndromes, were more likely to have had any female relative than any male first-degree relatives with stroke history.
Objective: We aimed to assess the relationship between C-reactive protein (CRP) and the severity and diffusion of coronary artery lesions in patients with unstable angina pectoris (UAP) and the independent association of CRP with this clinical situation.
The US Food and Drug Administration (FDA) has granted approval of the first generic formulation of enoxaparin (Lovenox, Sanofi-Aventis) sodium injection, a low-molecular-weight heparin used for multiple indications, including the treatment of acute ST-segment-elevation MI and the prevention of ischemic complications from unstable angina and non-Q-wave MI 1 .
The composite end point of death or hospitalization due to non-fatal myocardial infarction, repeated revascularization or unstable angina, was determined during one year of follow-up.
METHODS: We randomly assigned 17,802 apparently healthy men and women with low-density lipoprotein (LDL) cholesterol levels of less than 130 mg per deciliter (3.4 mmol per liter) and high-sensitivity C-reactive protein levels of 2.0 mg per liter or higher to rosuvastatin, 20 mg daily, or placebo and followed them for the occurrence of the combined primary end point of myocardial infarction, stroke, arterial revascularization, hospitalization for unstable angina, or death from cardiovascular causes.