angina pectoris
   HOME

TheInfoList



OR:

Angina, also known as angina pectoris, is
chest pain Chest pain is pain or discomfort in the chest, typically the front of the chest. It may be described as sharp, dull, pressure, heaviness or squeezing. Associated symptoms may include pain in the shoulder, arm, upper abdomen, or jaw, along with na ...
or pressure, usually caused by insufficient blood flow to the heart muscle (myocardium). It is most commonly a symptom of
coronary artery disease Coronary artery disease (CAD), also called coronary heart disease (CHD), ischemic heart disease (IHD), myocardial ischemia, or simply heart disease, involves the reduction of blood flow to the heart muscle due to build-up of atherosclerotic pl ...
. Angina is typically the result of obstruction or spasm of the arteries that supply blood to the heart muscle. The main mechanism of coronary artery obstruction is
atherosclerosis Atherosclerosis is a pattern of the disease arteriosclerosis in which the wall of the artery An artery (plural arteries) () is a blood vessel in humans and most animals that takes blood away from the heart to one or more parts of the body ...
as part of coronary artery disease. Other causes of angina include abnormal heart rhythms,
heart failure Heart failure (HF), also known as congestive heart failure (CHF), is a syndrome, a group of signs and symptoms caused by an impairment of the heart's blood pumping function. Symptoms typically include shortness of breath, Fatigue (medical), exc ...
and, less commonly,
anemia Anemia or anaemia (British English) is a blood disorder in which the blood has a reduced ability to carry oxygen due to a lower than normal number of red blood cells, or a reduction in the amount of hemoglobin. When anemia comes on slowly, th ...
. The term derives from the
Latin Latin (, or , ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through ...
''angere'' ("to strangle") and ''pectus'' ("chest"), and can therefore be translated as "a strangling feeling in the chest". There is a weak relationship between severity of angina and degree of oxygen deprivation in the heart muscle, however, the severity of angina does not always match the degree of oxygen deprivation to the heart or the risk of a
myocardial infarction A myocardial infarction (MI), commonly known as a heart attack, occurs when Hemodynamics, blood flow decreases or stops to the coronary artery of the heart, causing ischemia, damage to the cardiac muscle, heart muscle. The most common symptom i ...
(heart attack). Some people may experience severe pain even though there is little risk of a heart attack. Others may have a heart attack and experience little or no pain. In some cases, angina can be quite severe. Worsening angina attacks, sudden-onset angina at rest, and angina lasting more than 15 minutes are symptoms of unstable angina (usually grouped with similar conditions as the
acute coronary syndrome Acute coronary syndrome (ACS) is a syndrome (a set of signs and symptoms) due to decreased blood flow in the coronary artery, coronary arteries such that part of the cardiac muscle, heart muscle is unable to function properly or Necrosis, dies. ...
). As these may precede a heart attack, they require urgent medical attention and are, in general, treated similarly to myocardial infarction. In the early 20th century, severe angina was seen as a sign of impending death. However, modern medical therapies have improved the outlook substantially. Middle-age patients who experience moderate to severe angina ( grading by classes II, III, and IV) have a five-year survival rate of approximately 92%.


Classification


Stable angina

Also known as 'effort angina', this refers to the classic type of angina related to
myocardial ischemia Coronary artery disease (CAD), also called coronary heart disease (CHD), ischemic heart disease (IHD), myocardial ischemia, or simply heart disease, involves Ischemia, the reduction of blood flow to the myocardium, heart muscle due to build-up o ...
. A typical presentation of stable angina is that of chest discomfort and associated symptoms precipitated by some activity (running, walking, etc.) with minimal or non-existent symptoms at rest or after administration of sublingual
nitroglycerin Nitroglycerin (NG), (alternative spelling of nitroglycerine) also known as trinitroglycerin (TNG), nitro, glyceryl trinitrate (GTN), or 1,2,3-trinitroxypropane, is a dense, colorless, oily, explosive liquid most commonly produced by nitration, n ...
. Symptoms typically abate several minutes after activity and recur when activity resumes. In this way, stable angina may be thought of as being similar to intermittent claudication symptoms. Other recognized precipitants of stable angina include cold weather, heavy meals, and emotional stress.


Unstable angina

Unstable angina (UA) (also "''crescendo angina''"; this is a form of
acute coronary syndrome Acute coronary syndrome (ACS) is a syndrome (a set of signs and symptoms) due to decreased blood flow in the coronary artery, coronary arteries such that part of the cardiac muscle, heart muscle is unable to function properly or Necrosis, dies. ...
) is defined as angina pectoris that changes or worsens. It has at least one of these three features: # it occurs at rest (or with minimal exertion), usually lasting more than 10 minutes # it is severe and of new-onset (i.e., within the prior 4–6 weeks) # it occurs with a crescendo pattern (i.e., distinctly more severe, prolonged, or frequent than before). UA may occur unpredictably at rest, which may be a serious indicator of an impending heart attack. What differentiates stable angina from unstable angina (other than symptoms) is the pathophysiology of the atherosclerosis. The pathophysiology of unstable angina is the reduction of coronary flow due to transient platelet aggregation on apparently normal endothelium, coronary artery spasms, or coronary thrombosis. The process starts with atherosclerosis, progresses through inflammation to yield an active unstable plaque, which undergoes thrombosis and results in acute myocardial ischemia, which, if not reversed, results in cell necrosis (infarction). Studies show that 64% of all unstable anginas occur between 22:00 and 08:00 when patients are at rest. In stable angina, the developing atheroma is protected with a fibrous cap. This cap may rupture in unstable angina, allowing blood clots to precipitate and further decrease the area of the coronary vessel's lumen. This explains why, in many cases, unstable angina develops independently of activity.


Microvascular angina

Microvascular angina, also known as ''cardiac syndrome X'', is characterized by angina-like chest pain, in the context of normal epicardial coronary arteries (the largest vessels on the surface of the heart, prior to significant branching) on
angiography Angiography or arteriography is a medical imaging technique used to visualize the inside, or lumen (anatomy), lumen, of blood vessels and organs of the body, with particular interest in the artery, arteries, veins, and the Heart#Chambers, heart ...
. The original definition of cardiac syndrome X also mandated that ischemic changes on exercise (despite normal coronary arteries) were displayed, as shown on
cardiac stress test A cardiac stress test (also referred to as a cardiac diagnostic test, cardiopulmonary exercise test, or abbreviated CPX test) is a cardiology, cardiological test that measures the heart's ability to respond to external Stress (biology), stress in ...
s. The primary cause of microvascular angina is unknown, but factors apparently involved are endothelial dysfunction and reduced flow (perhaps due to spasm) in the tiny "resistance" blood vessels of the heart. Since microvascular angina is not characterized by major arterial blockages, it is harder to recognize and diagnose. Microvascular angina was previously considered a rather benign condition, but more recent data has changed this attitude. Studies, including the Women's Ischemia Syndrome Evaluation (WISE), suggest that microvascular angina is part of the pathophysiology of ischemic heart disease, perhaps explaining the higher rates of angina in women than in men, as well as their predilection towards
ischemia Ischemia American and British English spelling differences#ae and oe, or ischaemia is a restriction in blood supply to any tissue (biology), tissue, Skeletal muscle, muscle group, or Organ (biology), organ of the body, causing a shortage of oxyg ...
and acute coronary syndromes in the absence of obstructive coronary artery disease.


Signs and symptoms

Angina pectoris can be quite painful, but many patients with angina complain of chest discomfort rather than actual pain: the discomfort is usually described as a pressure, heaviness, tightness, squeezing, burning, or choking sensation. Apart from chest discomfort, anginal pains may also be experienced in the epigastrium (upper central abdomen), back, neck area, jaw, or shoulders. This is explained by the concept of referred pain and is because the spinal level that receives visceral sensation from the heart simultaneously receives cutaneous sensation from parts of the skin specified by that spinal nerve's dermatome, without an ability to discriminate the two. Typical locations for referred pain are arms (often inner left arm), shoulders, and neck into the jaw. Angina is typically precipitated by exertion or emotional stress. It is exacerbated by having a full stomach and by cold temperatures. Pain may be accompanied by breathlessness, sweating, and nausea in some cases. In this case, the pulse rate and the blood pressure increases. Chest pain lasting only a few seconds is normally not angina (such as precordial catch syndrome). Myocardial
ischemia Ischemia American and British English spelling differences#ae and oe, or ischaemia is a restriction in blood supply to any tissue (biology), tissue, Skeletal muscle, muscle group, or Organ (biology), organ of the body, causing a shortage of oxyg ...
comes about when the myocardium (the heart muscle) receives insufficient blood and oxygen to function normally either because of increased oxygen demand by the myocardium or because of decreased supply to the myocardium. This inadequate perfusion of blood and the resulting reduced delivery of oxygen and nutrients are directly correlated to blocked or narrowed blood vessels. Some experience "autonomic symptoms" (related to increased activity of the
autonomic nervous system The autonomic nervous system (ANS), formerly referred to as the vegetative nervous system, is a division of the peripheral nervous system that supplies viscera, internal organs, smooth muscle and glands. The autonomic nervous system is a control ...
) such as
nausea Nausea is a diffuse sensation of unease and discomfort, sometimes perceived as an urge to vomiting, vomit. While not painful, it can be a debilitating symptom if prolonged and has been described as placing discomfort on the chest, abdomen, or b ...
,
vomiting Vomiting (also known as emesis and throwing up) is the involuntary, forceful expulsion of the contents of one's stomach through the mouth and sometimes the Human nose, nose. Vomiting can be the result of ailments like Food-poisoning, foo ...
, and
pallor Pallor is a pale color of the skin that can be caused by illness, emotional shock or stress, stimulant use, or anemia, and is the result of a reduced amount of hemoglobin, oxyhaemoglobin and may also be visible as pallor of the Conjunctiva, con ...
. Major risk factors for angina include
cigarette smoking Tobacco smoking is the practice of burning tobacco and ingesting the resulting smoke. The smoke may be inhaled, as is done with cigarettes, or simply released from the mouth, as is generally done with pipes and cigars. The practice is believ ...
,
diabetes Diabetes, also known as diabetes mellitus, is a group of metabolic disorders characterized by a high blood sugar level ( hyperglycemia) over a prolonged period of time. Symptoms often include frequent urination, increased thirst and increase ...
, high cholesterol,
high blood pressure Hypertension (HTN or HT), also known as high blood pressure (HBP), is a Chronic condition, long-term Disease, medical condition in which the blood pressure in the artery, arteries is persistently elevated. High blood pressure usually does not ...
, sedentary lifestyle, and family history of premature heart disease. A variant form of angina— Prinzmetal's angina—occurs in patients with normal coronary arteries or insignificant atherosclerosis. It is believed caused by spasms of the artery. It occurs more in younger women. Coital angina, also known as ''angina d'amour'', is angina subsequent to
sexual intercourse Sexual intercourse (or coitus or copulation) is a sexual activity typically involving the insertion and Pelvic thrust, thrusting of the penis into the vagina for Sexual stimulation, sexual pleasure or sexual reproduction, reproduction.Sexual i ...
. It is generally rare, except in patients with severe
coronary artery disease Coronary artery disease (CAD), also called coronary heart disease (CHD), ischemic heart disease (IHD), myocardial ischemia, or simply heart disease, involves the reduction of blood flow to the heart muscle due to build-up of atherosclerotic pl ...
.


Cause


Major risk factors

Routine counseling of adults by physicians to advise them to improve their diet and increase their physical activity has, in general, been found to induce only small changes in actual behavior. Therefore, as of 2012, The U.S. Preventive Services Task Force does not recommend routine lifestyle counseling of all patients without known cardiovascular disease, hypertension, hyperlipidemia, or diabetes, and instead recommends selectively counseling only those patients who seem most ready to make lifestyle changes and using available time with other patients to explore other types of intervention that would be more likely to have a preventative impact. ; Conditions that exacerbate or provoke angina One study found that smokers with coronary artery disease had a significantly increased level of sympathetic nerve activity when compared to those without. This is in addition to increases in blood pressure, heart rate, and peripheral vascular resistance associated with nicotine, which may lead to recurrent angina attacks. In addition, the
Centers for Disease Control and Prevention The Centers for Disease Control and Prevention (CDC) is the National public health institutes, national public health agency of the United States. It is a Federal agencies of the United States, United States federal agency, under the United S ...
(CDC) reports that the risk of CHD (Coronary heart disease), stroke, and PVD (Peripheral vascular disease) is reduced within 1–2 years of smoking cessation. In another study, it was found that, after one year, the prevalence of angina in smoking men under 60 after an initial attack was 40% less in those having quit smoking compared to those that continued. Studies have found that there are short-term and long-term benefits to smoking cessation.


Other medical problems

* Esophageal disorders *
Gastroesophageal reflux disease Gastroesophageal reflux disease (GERD) or gastro-oesophageal reflux disease (GORD) is one of the upper gastrointestinal chronic diseases where stomach content persistently and regularly flows up into the esophagus, resulting in symptoms and/ ...
(GERD) * Hyperthyroidism * Hypoxemia * Profound
anemia Anemia or anaemia (British English) is a blood disorder in which the blood has a reduced ability to carry oxygen due to a lower than normal number of red blood cells, or a reduction in the amount of hemoglobin. When anemia comes on slowly, th ...
* Uncontrolled
hypertension Hypertension (HTN or HT), also known as high blood pressure (HBP), is a Chronic condition, long-term Disease, medical condition in which the blood pressure in the artery, arteries is persistently elevated. High blood pressure usually does not ...


Other cardiac problems

* Bradyarrhythmia *
Hypertrophic cardiomyopathy Hypertrophic cardiomyopathy (HCM, or HOCM when #Variants, obstructive) is a condition in which the heart becomes hypertrophy, thickened without an obvious cause. The parts of the heart most commonly affected are the interventricular septum and t ...
* Tachyarrhythmia *
Valvular heart disease Valvular heart disease is any cardiovascular disease process involving one or more of the four Heart valve, valves of the heart (the aortic valve, aortic and mitral valves on the left side of heart and the pulmonary valve, pulmonic and tricuspid ...
Myocardial ischemia Coronary artery disease (CAD), also called coronary heart disease (CHD), ischemic heart disease (IHD), myocardial ischemia, or simply heart disease, involves Ischemia, the reduction of blood flow to the myocardium, heart muscle due to build-up o ...
can result from: # a reduction of blood flow to the heart that can be caused by
stenosis A stenosis (from Ancient Greek στενός, "narrow") is an abnormal narrowing in a blood vessel or other tubular Organ (anatomy), organ or structure such as foramina and canals. It is also sometimes called a stricture (as in urethral stricture) ...
, spasm, or acute occlusion (by an embolus) of the heart's arteries. # resistance of the blood vessels. This can be caused by narrowing of the blood vessels; a decrease in radius. Blood flow is proportional to the radius of the artery to the fourth power. # reduced oxygen-carrying capacity of the blood, due to several factors such as a decrease in oxygen tension and hemoglobin concentration. This decreases the ability of hemoglobin to carry oxygen to myocardial tissue.
Atherosclerosis Atherosclerosis is a pattern of the disease arteriosclerosis in which the wall of the artery An artery (plural arteries) () is a blood vessel in humans and most animals that takes blood away from the heart to one or more parts of the body ...
is the most common cause of
stenosis A stenosis (from Ancient Greek στενός, "narrow") is an abnormal narrowing in a blood vessel or other tubular Organ (anatomy), organ or structure such as foramina and canals. It is also sometimes called a stricture (as in urethral stricture) ...
(narrowing of the blood vessels) of the heart's arteries and, hence, angina pectoris. Some people with chest pain have normal or minimal narrowing of heart arteries; in these patients, vasospasm is a more likely cause for the pain, sometimes in the context of Prinzmetal's angina and syndrome X. Myocardial ischemia also can be the result of factors affecting blood composition, such as the reduced oxygen-carrying capacity of
blood Blood is a body fluid in the circulatory system of humans and other vertebrates that delivers necessary substances such as nutrients and oxygen to the Cell (biology), cells, and transports Metabolic waste, metabolic waste products away from th ...
, as seen with severe
anemia Anemia or anaemia (British English) is a blood disorder in which the blood has a reduced ability to carry oxygen due to a lower than normal number of red blood cells, or a reduction in the amount of hemoglobin. When anemia comes on slowly, th ...
(low number of red blood cells), or long-term
smoking Smoking is a practice in which a substance is burned and the resulting smoke is typically breathed in to be tasted and absorbed into the bloodstream. Most commonly, the substance used is the dried leaves of the tobacco plant, which have bee ...
.


Pathophysiology

Angina results when there is an imbalance between the heart's oxygen demand and supply. This imbalance can result from an increase in demand (e.g., during exercise) without a proportional increase in supply (e.g., due to obstruction or atherosclerosis of the coronary arteries). However, the pathophysiology of angina in females varies significantly as compared to males. Non-obstructive coronary disease is more common in females.


Diagnosis

Angina should be suspected in people presenting tight, dull, or heavy chest discomfort that is:NHS Clinical Knowledge Summaries (2009) Angina - stable. Date site accessed: 04/01/2009 # Retrosternal or left-sided, radiating to the left arm, neck, jaw, or back. # Associated with exertion or emotional stress and relieved within several minutes by rest. # Precipitated by cold weather or a meal. Some people present with atypical symptoms, including breathlessness, nausea, or epigastric discomfort, or burning. These atypical symptoms are particularly likely in older people, women, and those with diabetes. Anginal pain is not usually sharp or stabbing or influenced by respiration. Antacids and simple
analgesic An analgesic drug, also called simply an analgesic (American English), analgaesic (British English), pain reliever, or painkiller, is any member of the group of Pharmaceutical drug, drugs used to achieve relief from pain (that is, analgesia or p ...
s do not usually relieve the pain. If chest discomfort (of whatever site) is precipitated by exertion, relieved by rest, and relieved by glyceryl trinitrate, the likelihood of angina is increased. In angina patients momentarily not feeling any chest pain, an electrocardiogram (ECG) is typically normal unless there have been other cardiac problems in the past. During periods of pain, depression, or elevation of the
ST segment In electrocardiography, the ST segment connects the QRS complex and the T wave and has a duration of 0.005 to 0.150 sec (5 to 150 ms). It starts at the J point (junction between the QRS complex and ST segment) and ends at the beginning of the T ...
may be observed. To elicit these changes, an exercise ECG test ("treadmill test") may be performed, during which the patient exercises to his/her maximum ability before fatigue, breathlessness, or pain intervenes; if characteristic ECG changes are documented (typically more than 1 mm of flat or downsloping ST depression), the test is considered diagnostic for angina. Even constant monitoring of the blood pressure and the pulse rate can lead to some conclusions regarding angina. The exercise test is also useful in looking for other markers of myocardial ischemia: blood pressure response (or lack thereof, in particular, a drop in systolic blood pressure), dysrhythmia, and chronotropic response. Other alternatives to a standard exercise test include a thallium scintigram or sestamibi scintigram (in patients unable to exercise enough for the treadmill tests, e.g., due to
asthma Asthma is a chronic (medicine), long-term inflammation, inflammatory disease of the bronchi, airways of the lungs. It is characterized by variable and recurring symptoms, reversible Airway obstruction, airflow obstruction, and easily triggered ...
or
arthritis Arthritis is a term often used to mean any disorder that affects joints. Symptoms generally include joint pain and stiffness. Other symptoms may include redness, warmth, Joint effusion, swelling, and decreased range of motion of the affected j ...
or in whom the ECG is too abnormal at rest) or stress echocardiography. In patients in whom such noninvasive testing is diagnostic, a coronary angiogram is typically performed to identify the nature of the coronary lesion, and whether this would be a candidate for
angioplasty Angioplasty, is also known as balloon angioplasty and percutaneous transluminal angioplasty (PTA), is a minimally invasive procedure, minimally invasive endovascular surgery, endovascular Medical procedure, procedure used to widen narrowed or o ...
, coronary artery bypass graft (CABG), treatment only with medication, or other treatments. In hospitalized patients with unstable angina (or the newer term of "high-risk acute coronary syndromes"), those with resting ischaemic ECG changes or those with raised cardiac enzymes such as
troponin image:Troponin Ribbon Diagram.png, 400px, Ribbon representation of the human cardiac troponin core complex (52 kDa core) in the calcium-saturated form. Blue = troponin C; green = troponin I; magenta = troponin T.; ; rendered with PyMOL Troponin, ...
may undergo coronary angiography directly.


Treatment

Angina pectoris occurs as a result of coronary blood flow insufficiency in the face of increased oxygen demand. The principal goal in the prevention and relief of angina is to limit the oxygen requirement of the heart so it can meet the inadequate oxygen supply derived through the blood supplied from the stenosed or constricted arteries. The main goals of treatment in angina pectoris are relief of symptoms, slowing progression of the disease, and reduction of future events, especially
heart attacks A myocardial infarction (MI), commonly known as a heart attack, occurs when Hemodynamics, blood flow decreases or stops to the coronary artery of the heart, causing ischemia, damage to the cardiac muscle, heart muscle. The most common symptom i ...
and death. Beta blockers (e.g., carvedilol, metoprolol,
propranolol Propranolol, sold under the brand name Inderal among others, is a medication of the beta blocker class. It is used to treat high blood pressure, a number of types of irregular heart rate, thyrotoxicosis, capillary hemangiomas, performanc ...
) have a large body of evidence in morbidity and mortality benefits (fewer symptoms, less disability, and longer life) and short-acting
nitroglycerin Nitroglycerin (NG), (alternative spelling of nitroglycerine) also known as trinitroglycerin (TNG), nitro, glyceryl trinitrate (GTN), or 1,2,3-trinitroxypropane, is a dense, colorless, oily, explosive liquid most commonly produced by nitration, n ...
medications have been used since 1879 for symptomatic relief of angina. There are differing course of treatments for the patient depending on the type of angina the patient has. However, this second can provide a brief overview of the types of medications provided for angina and the purpose by which they are prescribed.
Beta blocker Beta blockers, also spelled β-blockers, are a class of medications that are predominantly used to manage cardiac arrhythmia, abnormal heart rhythms, and to protect the heart from a second myocardial infarction, heart attack after a first heart ...
s, specifically B1 adrenergic blockers without intrinsic sympathomimetic activity are the most preferred for the angina treatment out of B1 selective and non-selective as well as B1 ISA agents. B1 blockers are cardioselective blocking agents such as Nevibolol, Atenolol, Metoprolol and Bisoprolol, which result in blocking cAMP in the heart muscle cells. The cAMP which plays a vital role in phosphorylating the ryanodine receptor and LTCC will usually increase Ca+2 levels in the heart muscle cells, which will then result in contraction is blocked. Therefore, B1 blockade decreases the HR and contraction of the heart muscle, making it need less oxygen demand. An important thing to note is that the B1 cardioselective blockers are cardioselective and not cardio specific. This means that if the beta-adrenergic antagonist is prescribed in higher doses, it can lose the selectivity aspect and begin causing hypertension from B2 adrenergic stimulation of smooth muscle cells. This is why in therapy for patients with angina, the vasodilatory organonitrates complement the use of B-blockers when prescribed the use of angina. The preference for Beta-1 cardioselective blockers is for B1 cardioselective blockers without instrinsic sympathetic activity. Beta blockers with intrinsic sympathetic activity will still do the beta blockade of the heart muscle cells and have a decreased ionotrophic and chronotropic effect, but this effect will be to a lesser extent than if the beta blocker did not have the instrinsic sympathetic activity. A common beta-blocker with ISA prescribed for the treatment of angina is Acebutolol. Non-selective beta-adrenergic antagonists will yield the same action on B1 receptors, however will also act on B2 receptors. These medications, such as Propranolol and Nadolol, act on B1 receptors on smooth muscle cells as well. B1 blockade occurs in the smooth muscle cells. Specifically cAMP is responsible for inhibiting Myosin Light Kinase, the enzyme responsible for acting on Actin-Myosin. The inhibition of B1 will result in decreased levels of cAMP which will lead to increased levels of Myosin Light Chain Kinase in the smooth muscle cells, the enzyme responsible for acting on Actin-Myosin and leading to contraction of the smooth muscle cell. This increased contraction of the smooth muscle cell from B1 blockade is not desirable since it explains the hypertension that may arise with patients taking that medication.
Calcium channel blocker Calcium channel blockers (CCB), calcium channel antagonists or calcium antagonists are a group of medication A medication (also called medicament, medicine, pharmaceutical drug, medicinal drug or simply drug) is a drug used to medical dia ...
s act to decrease the heart's workload, and thus its requirement for oxygen by blocking the calcium channels of the heart muscle cell. With decreased intracellular calcium, the calcium-troponin complex does not form in the heart muscle cell and it does not contract, therefore reducing the need for oxygen. The other class of medication that can be used to treat angina are the organic nitrates. Organic nitrates are used extensively to treat angina. They improve coronary blood flow of the coronary arteries (arteries which supply blood to the heart muscle) by reversing and preventing vasospasm, which increases the blood flow to the heart, improving perfusion and oxygen delivery to the heart associated with the pain of angina. These drugs also reduce systemic vascular resistance, of both veins and arteries but the veins to a greater extent. The decrease in the resistance of the arteries and veins decreases the myocardial oxygen demand, which also reduces myocardial oxygen demand.
Nitroglycerin Nitroglycerin (NG), (alternative spelling of nitroglycerine) also known as trinitroglycerin (TNG), nitro, glyceryl trinitrate (GTN), or 1,2,3-trinitroxypropane, is a dense, colorless, oily, explosive liquid most commonly produced by nitration, n ...
is a potent vasodilator that decreases myocardial oxygen demand by decreasing the heart's workload. Nitroglycerin should not be given if certain inhibitors such as sildenafil, tadalafil, or vardenafil have been taken within the previous 12 hours as the combination of the two could cause a serious drop in blood pressure. Treatments for angina are balloon angioplasty, in which the balloon is inserted at the end of a
catheter In medicine, a catheter (/ˈkæθətər/) is a thin tubing (material), tube made from medical grade materials serving a broad range of functions. Catheters are medical devices that can be inserted in the body to treat diseases or perform a surgi ...
and inflated to widen the arterial lumen.
Stent In medicine, a stent is a metal or plastic tube inserted into the Lumen (anatomy), lumen of an anatomic vessel or duct to keep the passageway open, and stenting is the placement of a stent. A wide variety of stents are used for different purpose ...
s to maintain the arterial widening are often used at the same time. Coronary bypass surgery involves bypassing constricted arteries with venous grafts. This is much more invasive than
angioplasty Angioplasty, is also known as balloon angioplasty and percutaneous transluminal angioplasty (PTA), is a minimally invasive procedure, minimally invasive endovascular surgery, endovascular Medical procedure, procedure used to widen narrowed or o ...
. Calcium channel blockers (such as nifedipine (Adalat) and amlodipine), isosorbide mononitrate and nicorandil are vasodilators commonly used in chronic stable angina. A new therapeutic class, called If inhibitor, has recently been made available: Ivabradine provides heart rate reduction without affecting contractility leading to major anti-ischemic and antianginal efficacy. ACE inhibitors are also vasodilators with both symptomatic and prognostic benefit. Statins are the most frequently used lipid/cholesterol modifiers, which probably also stabilize existing atheromatous plaque. Low-dose
aspirin Aspirin, also known as acetylsalicylic acid (ASA), is a nonsteroidal anti-inflammatory drug (NSAID) used to reduce pain, fever, and/or inflammation, and as an antithrombotic. Specific inflammatory conditions which aspirin is used to treat inc ...
decreases the risk of heart attack in patients with chronic stable angina, and was part of standard treatment. However, in patients without established cardiovascular disease, the increase in hemorrhagic stroke and gastrointestinal bleeding offsets any benefits and it is no longer advised unless the risk of myocardial infarction is very high. Exercise is also a very good long-term treatment for the angina (but only particular regimens – gentle and sustained exercise rather than intense short bursts), probably working by complex mechanisms such as improving blood pressure and promoting coronary artery collateralisation. Though sometimes used by patients, evidence does not support the use of traditional Chinese herbal products (THCP) for angina. Identifying and treating risk factors for further coronary heart disease is a priority in patients with angina. This means testing for elevated cholesterol and other fats in the blood,
diabetes Diabetes, also known as diabetes mellitus, is a group of metabolic disorders characterized by a high blood sugar level ( hyperglycemia) over a prolonged period of time. Symptoms often include frequent urination, increased thirst and increase ...
and
hypertension Hypertension (HTN or HT), also known as high blood pressure (HBP), is a Chronic condition, long-term Disease, medical condition in which the blood pressure in the artery, arteries is persistently elevated. High blood pressure usually does not ...
(high blood pressure), and encouraging smoking cessation and weight optimization. The calcium channel blocker nifedipine prolongs cardiovascular event- and procedure-free survival in patients with coronary artery disease. New overt heart failures were reduced by 29% compared to placebo; however, the mortality rate difference between the two groups was statistically insignificant.


Microvascular angina in women

Women with myocardial ischemia often have either no or atypical symptoms, such as palpitations, anxiety, weakness, and fatigue. Additionally, many women with angina are found to have cardiac ischemia, yet no evidence of obstructive coronary artery disease on cardiac catheterization. Evidence is accumulating that nearly half of women with myocardial ischemia have coronary microvascular disease, a condition often called microvascular angina (MVA). Small intramyocardial arterioles constrict in MVA causing ischemic pain that is less predictable than with typical epicardial coronary artery disease (CAD). The pathophysiology is complex and still being elucidated, but there is strong evidence that endothelial dysfunction, decreased endogenous vasodilators, inflammation, changes in adipokines, and platelet activation are contributing factors. The diagnosis of MVA may require catheterization during which there is an assessment of the microcirculatory response to adenosine or acetylcholine and measurement of coronary and fractional flow reserve. New techniques include positron emission tomography (PET) scanning, cardiac magnetic resonance imaging (MRI), and transthoracic Doppler echocardiography. Managing MVA can be challenging, for example, women with this condition have less coronary microvascular dilation in response to nitrates than do those without MVA. Women with MVA often have traditional risk factors for CAD such as obesity, dyslipidemia, diabetes, and hypertension. Aggressive interventions to reduce modifiable risk factors are an important component of management, especially smoking cessation, exercise, and diabetes management. The combination of non-nitrate vasodilators, such as calcium channel blockers and angiotensin-converting enzyme (ACE) inhibitors along with HMG-CoA reductase inhibitors (statins), also is effective in many women, and new drugs, such as Ranolazine and Ivabradine, have shown promise in the treatment of MVA. Other approaches include spinal cord stimulators, adenosine receptor blockade, and psychiatric intervention.


Suspected angina

Hospital admission for people with the following symptoms is recommended, as they may have unstable angina: pain at rest (which may occur at night), pain on minimal exertion, angina that seems to progress rapidly despite increasing medical treatment. All people with suspected angina should be urgently referred to a chest pain evaluation service, for confirmation of the diagnosis and assessment of the severity of coronary heart disease.


Epidemiology

As of 2010, angina due to ischemic heart disease affects approximately 112 million people (1.6% of the global population) being slightly more common in men than women (1.7% to 1.5%). In the United States, 10.2 million are estimated to experience angina with approximately 500,000 new cases occurring each year. Angina is more often the presenting symptom of coronary artery disease in women than in men. The prevalence of angina rises with increasing age, with a mean age of onset of 62.3 years. After five years post-onset, 4.8% of individuals with angina subsequently died from coronary heart disease. Men with angina were found to have an increased risk of subsequent acute myocardial infarction and coronary heart disease related death than women. Similar figures apply in the remainder of the Western world. All forms of coronary heart disease are much less-common in the
Third World The term "Third World" arose during the Cold War to define countries that remained non-aligned with either NATO or the Warsaw Pact. The United States, Canada, Japan, South Korea, Western European nations and their allies represented the "First W ...
, as its risk factors are much more common in Western and Westernized countries; it could, therefore, be termed a disease of affluence.


History

The condition was named "hritshoola" in ancient India and was described by Sushruta (6th century BC). The first clinical description of ''angina pectoris'' was by a British physician Dr. William Heberden in 1768.


References


External links


Treatment of stable angina recommendations for patients
in layman's terms
British Heart Foundation - Angina

Angina Pectoris Animation Video 3D

Guidelines on the management of stable angina pectoris - European Society of Cardiology

Heart Attack and Angina Statistics
by American Heart Association: Final 2006 statistics for the United States {{DEFAULTSORT:Angina Pectoris Acute pain Ischemic heart diseases