A coronary occlusion, or coronary artery disease, is the partial or complete obstruction of blood flow in a

coronary artery The coronary arteries are the arterial blood vessels of coronary circulation, which transport oxygenated blood to the heart muscle. The heart requires a continuous supply of oxygen to function and survive, much like any other tissue or organ of ...

. This condition was first discussed in 1910 by Sir William Osler. This condition slows or blocks the supply of oxygen-rich blood to the

heart The heart is a muscular Organ (biology), organ found in humans and other animals. This organ pumps blood through the blood vessels. The heart and blood vessels together make the circulatory system. The pumped blood carries oxygen and nutrie ...

. This condition can lead to

myocardial ischemia Coronary artery disease (CAD), also called coronary heart disease (CHD), or ischemic heart disease (IHD), is a type of heart disease involving the reduction of blood flow to the cardiac muscle due to a build-up of atheromatous plaque in the a ...

and if untreated, may cause a

heart attack A myocardial infarction (MI), commonly known as a heart attack, occurs when Ischemia, blood flow decreases or stops in one of the coronary arteries of the heart, causing infarction (tissue death) to the heart muscle. The most common symptom ...

and heart failure. It is the most common form of

cardiovascular disease Cardiovascular disease (CVD) is any disease involving the heart or blood vessels. CVDs constitute a class of diseases that includes: coronary artery diseases (e.g. angina, heart attack), heart failure, hypertensive heart disease, rheumati ...

, and is the leading cause of death in the United States, affecting 18 million adults.

Description

A coronary occlusion can be caused by smoking, having other heart or blood conditions, or being physically inactive. It is also

hereditary Heredity, also called inheritance or biological inheritance, is the passing on of traits from parents to their offspring; either through asexual reproduction or sexual reproduction, the offspring cells or organisms acquire the genetic inform ...

. Symptoms include chest pain, shortness of breath, pain in upper body, fatigue, nausea, an irregular heartbeat, and drowsiness. To diagnose a coronary occlusion, a doctor may view a patient's medical history, or perform a coronary angiography; a doctor will stick a

catheter In medicine, a catheter ( ) 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 surgical procedure. ...

into the wrist or groin, lead it to the heart, and inject a liquid for X-ray imaging. To treat a coronary occlusion, medication may be used to relieve symptoms.

Percutaneous coronary intervention Percutaneous coronary intervention (PCI) is a minimally invasive non-surgical procedure used to treat stenosis, narrowing of the coronary artery, coronary arteries of the heart found in coronary artery disease. The procedure is used to place and ...

coronary artery bypass surgery Coronary artery bypass surgery, also known as coronary artery bypass graft (CABG, pronounced "cabbage"), is a surgical procedure to treat coronary artery disease (CAD), the buildup of plaques in the arteries of the heart. It can relieve chest ...

may also be used.

Signs and symptoms

Symptoms include chest pain or

angina Angina, also known as angina pectoris, is chest pain or pressure, usually caused by insufficient blood flow to the heart muscle (myocardium). It is most commonly a symptom of coronary artery disease. Angina is typically the result of parti ...

shortness of breath Shortness of breath (SOB), known as dyspnea (in AmE) or dyspnoea (in BrE), is an uncomfortable feeling of not being able to breathe well enough. The American Thoracic Society defines it as "a subjective experience of breathing discomfort that con ...

, and

fatigue Fatigue is a state of tiredness (which is not sleepiness), exhaustion or loss of energy. It is a signs and symptoms, symptom of any of various diseases; it is not a disease in itself. Fatigue (in the medical sense) is sometimes associated wit ...

. A completely blocked coronary artery will cause a heart attack. Common heart attack symptoms include chest pain or

, pain or discomfort that spreads to the shoulder, arm, back, neck jaw, teeth or the upper belly, cold sweats, fatigue,

heartburn Heartburn is a burning sensation felt behind the breastbone. It is a symptom that is commonly linked to acid reflux and is often triggered by food, particularly fatty, sugary, spicy, chocolate, citrus, onion-based and tomato-based products. Ly ...

nausea Nausea is a diffuse sensation of unease and discomfort, sometimes perceived as an urge to vomit. It can be a debilitating symptom if prolonged and has been described as placing discomfort on the chest, abdomen, or back of the throat. Over 30 d ...

, or

lightheadedness Lightheadedness is a common and typically unpleasant sensation of dizziness or a feeling that one may faint. The sensation of lightheadedness can be short-lived, prolonged, or, rarely, recurring. In addition to dizziness, the individual may fee ...

Causes

Coronary occlusion is caused by the buildup of fats,

cholesterol Cholesterol is the principal sterol of all higher animals, distributed in body Tissue (biology), tissues, especially the brain and spinal cord, and in Animal fat, animal fats and oils. Cholesterol is biosynthesis, biosynthesized by all anima ...

and other substances in and on the walls of the hearts

arteries An artery () is a blood vessel in humans and most other animals that takes oxygenated blood away from the heart in the systemic circulation to one or more parts of the body. Exceptions that carry deoxygenated blood are the pulmonary arteries in ...

. As plaque builds up, the arteries narrow. Plaque often starts building up during childhood and is heavily influenced by genetics, but also lifestyle and high blood cholesterol. This condition is referred to as

atherosclerosis Atherosclerosis is a pattern of the disease arteriosclerosis, characterized by development of abnormalities called lesions in walls of arteries. This is a chronic inflammatory disease involving many different cell types and is driven by eleva ...

. The buildup on the walls of the hearts arteries is referred to as plaque. Plaque causes arteries to narrow and block blood flow. Conditions that aid in the development of coronary artery disease are

diabetes Diabetes mellitus, commonly known as diabetes, is a group of common endocrine diseases characterized by sustained high blood sugar levels. Diabetes is due to either the pancreas not producing enough of the hormone insulin, or the cells of th ...

insulin resistance Insulin resistance (IR) is a pathological response in which cells in insulin-sensitive tissues in the body fail to respond normally to the hormone insulin or downregulate insulin receptors in response to hyperinsulinemia. Insulin is a horm ...

high blood pressure Hypertension, also known as high blood pressure, is a long-term medical condition in which the blood pressure in the arteries is persistently elevated. High blood pressure usually does not cause symptoms itself. It is, however, a major ri ...

sedentary lifestyle Sedentary lifestyle is a Lifestyle (social sciences), lifestyle type, in which one is physically inactive and does little or no physical movement and/or exercise. A person living a sedentary lifestyle is often sitting or lying down while enga ...

, and

smoking Smoking is a practice in which a substance is combusted, and the resulting smoke is typically inhaled to be tasted and absorbed into the bloodstream of a person. Most commonly, the substance used is the dried leaves of the tobacco plant, whi ...

tobacco Tobacco is the common name of several plants in the genus '' Nicotiana'' of the family Solanaceae, and the general term for any product prepared from the cured leaves of these plants. More than 70 species of tobacco are known, but the ...

use. Risk Factors that are not controllable are age, birth sex, and

family history Genealogy () is the study of families, family history, and the tracing of their lineages. Genealogists use oral interviews, historical records, genetic analysis, and other records to obtain information about a family and to demonstrate kins ...

. Getting older increases the risk of damaged and narrowed arteries. Men are at a greater risk of coronary artery disease, with women's risk increasing after menopause.

Pathophysiology

Coronary occlusion is caused by plaque inside of the blood vessels that direct oxygen rich blood to the heart. Plaque is caused by fatty deposits and scar tissue that cling to the walls of coronary arteries. The development of plaque takes years and leads to

stenosis Stenosis () is the abnormal narrowing of a blood vessel or other tubular organ or structure such as foramina and canals. It is also sometimes called a stricture (as in urethral stricture). ''Stricture'' as a term is usually used when narrowing ...

of the

coronary arteries The coronary arteries are the arteries, arterial blood vessels of coronary circulation, which transport oxygenated blood to the Cardiac muscle, heart muscle. The heart requires a continuous supply of oxygen to function and survive, much like any ...

and progressively reduces blood flow. Due to the slower development of this condition, the body will adapt and create small blood vessels that circumvent the blockage. The small

blood vessels Blood vessels are the tubular structures of a circulatory system that transport blood throughout many animals’ bodies. Blood vessels transport blood cells, nutrients, and oxygen to most of the tissues of a body. They also take waste an ...

form a natural bypass of the blockage, but often do not supply enough blood to meet an increased demand when stressors are applied like

exercise Exercise or workout is physical activity that enhances or maintains fitness and overall health. It is performed for various reasons, including weight loss or maintenance, to aid growth and improve strength, develop muscles and the cardio ...

. When a plaque has a greater than 50% diameter stenosis, the reduced blood flow through the coronary artery during exertion may lead to

. Acute coronary events occur when a

thrombus A thrombus ( thrombi) is a solid or semisolid aggregate from constituents of the blood (platelets, fibrin, red blood cells, white blood cells) within the circulatory system during life. A blood clot is the final product of the blood coagulatio ...

forms due to disruption of a plaque. In acute heart attack, occlusion is greater than in

unstable angina In dynamical systems instability means that some of the outputs or internal states increase with time, without bounds. Not all systems that are not stable are unstable; systems can also be marginally stable or exhibit limit cycle behavior ...

, where arterial occlusion is not full blockage. Downstream embolism of thrombus may also produce microinfarcts.

Diagnosis

Heart disease is often undiagnosed until a serious problem occurs, such as

cardiac arrest Cardiac arrest (also known as sudden cardiac arrest CA is when the heart suddenly and unexpectedly stops beating. When the heart stops beating, blood cannot properly Circulatory system, circulate around the body and the blood flow to the ...

. Regular checkups can lead to an early diagnosis and preventative treatment. Screening tests and risk assessments should begin around age 20 if one does not have any risk factors. Screenings should begin in childhood if one has risk factors such as

obesity Obesity is a medical condition, considered by multiple organizations to be a disease, in which excess Adipose tissue, body fat has accumulated to such an extent that it can potentially have negative effects on health. People are classifi ...

, sedentary lifestyle, or a family history of heart conditions. Healthcare providers will run blood tests to check for

triglycerides A triglyceride (from ''wikt:tri-#Prefix, tri-'' and ''glyceride''; also TG, triacylglycerol, TAG, or triacylglyceride) is an ester derived from glycerol and three fatty acids. Triglycerides are the main constituents of body fat in humans and oth ...

lipoproteins A lipoprotein is a biochemical assembly whose primary function is to transport hydrophobic lipid (also known as fat) molecules in water, as in blood plasma or other extracellular fluids. They consist of a triglyceride and cholesterol center, sur ...

sugar Sugar is the generic name for sweet-tasting, soluble carbohydrates, many of which are used in food. Simple sugars, also called monosaccharides, include glucose Glucose is a sugar with the Chemical formula#Molecular formula, molecul ...

, or

proteins Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, re ...

that are a sign of

inflammation Inflammation (from ) is part of the biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or irritants. The five cardinal signs are heat, pain, redness, swelling, and loss of function (Latin ''calor'', '' ...

To assist in a diagnosis, healthcare providers may also order a electrocardiogram (ECG or EKG), coronary calcium scan,

stress test Stress testing is a form of deliberately intense or thorough testing, used to determine the stability of a given system, critical infrastructure or entity. It involves testing beyond normal operational capacity, often to a breaking point, in orde ...

, cardiac magnetic resonance imaging (MRI), cardiac positron emission tomography (PET), invasive

coronary angiography Coronary () may, as shorthand in English, be used to mean: * Coronary circulation, the system of arteries and veins in mammals ** Coronary artery disease ** Coronary occlusion ** A myocardial infarction, a heart attack As adjective * Referring to ...

, and/or coronary CT angiography.

Treatment

Healthcare providers may recommend lifelong heart-healthy lifestyle choices. These choices included a heart-healthy eating plan, physical activity, quitting smoking, improved

sleep hygiene Sleep hygiene is a behavioral and environmental practice developed in the late 1970s as a method to help people with mild to moderate insomnia. Clinicians assess the sleep hygiene of people with insomnia and other conditions, such as depressio ...

weight loss Weight loss, in the context of medicine, health, or physical fitness, refers to a reduction of the total body mass, by a mean loss of fluid, body fat (adipose tissue), or lean mass (namely bone mineral deposits, muscle, tendon, and other conn ...

, blood pressure control,

control, blood

pressure Pressure (symbol: ''p'' or ''P'') is the force applied perpendicular to the surface of an object per unit area over which that force is distributed. Gauge pressure (also spelled ''gage'' pressure)The preferred spelling varies by country and eve ...

control, and

stress management Stress management consists of a wide spectrum of techniques and psychotherapy, psychotherapies aimed at controlling a person's level of psychological stress, especially chronic stress, generally for the purpose of improving the function of everyda ...

. Some medications may be prescribed to allow the blood vessels to widen and help the heart pump include

ACE inhibitors Angiotensin-converting-enzyme inhibitors (ACE inhibitors) are a class of medication used primarily for the treatment of hypertension, high blood pressure and heart failure. This class of medicine works by causing relaxation of blood vessels as ...

beta blockers Beta blockers, also spelled β-blockers, are a class of medications that are predominantly used to manage abnormal heart rhythms (arrhythmia), and to protect the heart from a second heart attack after a first heart attack (secondary prevention). ...

calcium channel blockers Calcium channel blockers (CCB), calcium channel antagonists or calcium antagonists are a group of medications that disrupt the movement of calcium () through calcium channels. Calcium channel blockers are used as antihypertensive drugs, i.e., a ...

nitrates Nitrate is a polyatomic ion with the chemical formula . Salts containing this ion are called nitrates. Nitrates are common components of fertilizers and explosives. Almost all inorganic nitrates are soluble in water. An example of an insol ...

, and Ranolazine. Some medications may be prescribed to manage cholesterol include

statins Statins (or HMG-CoA reductase inhibitors) are a class of medications that lower cholesterol. They are prescribed typically to people who are at high risk of cardiovascular disease. Low-density lipoprotein (LDL) carriers of cholesterol play ...

, nonstatins, and fribrates. Some medications may be prescribed for other risk factors for heart disease like blood sugar and obesity such as empagliflozin, canagliflozin,

metformin Metformin, sold under the brand name Glucophage, among others, is the main first-line medication for the treatment of type2 diabetes, particularly in people who are overweight. It is also used in the treatment of polycystic ovary syndrome, ...

, liraglutide, orlistat, and

semaglutide Semaglutide is an anti-diabetic medication used for the treatment of type2 diabetes and an anti-obesity medication used for long-term weight management. It is a peptide similar to the hormone glucagon-like peptide-1 (GLP-1), modified with a ...

. Heart surgery may be needed to treat this condition. Some procedures include

percutaneous coronary intervention Percutaneous coronary intervention (PCI) is a minimally invasive non-surgical procedure used to treat stenosis, narrowing of the coronary artery, coronary arteries of the heart found in coronary artery disease. The procedure is used to place and ...

(PCI), coronary artery bypass grafting (CABG), and transmyocardial laser revascularization ( coronary endarterectomy). Preventative procedures like

bariatric surgery Bariatric surgery (also known as metabolic surgery or weight loss surgery) is a surgical procedure used to manage obesity and obesity-related conditions. Long term weight loss with bariatric surgery may be achieved through alteration of gut ho ...

can help lower coronary heart disease risk.

Prognosis

Coronary artery disease cannot be reversed. To reduce future problems, a patient may be referred to get exercise-based cardiac rehabilitation. Patients with coronary artery disease over 15-year period based on expectations in a 1-year follow up saw a mortality rate of those in the highest quartiles of expectations are 28-30 deaths per 100 patients. The lowest

quartile In statistics, quartiles are a type of quantiles which divide the number of data points into four parts, or ''quarters'', of more-or-less equal size. The data must be ordered from smallest to largest to compute quartiles; as such, quartiles are ...

of expectations are 50-57 deaths per 100 patients. Prognosis for heart attacks when people reach emergency care promptly improve dramatically, though many people still die before reaching the hospital. One out of every 10 patients who have a heart attack die within the first three to four months.

Epidemiology

Coronary artery disease is the leading cause of death in men and women. This condition is the cause of one third of all deaths, which is especially worse in areas with lower

socioeconomic Economics () is a behavioral science that studies the Production (economics), production, distribution (economics), distribution, and Consumption (economics), consumption of goods and services. Economics focuses on the behaviour and interac ...

status. Mortality is nearly five times higher in men than women, but mortality difference narrows with age. Black women are more likely than white women to have a heart attack. Black adults have a higher mortality rate than white adults from heart attack. Asian adults have the least incidence of

coronary artery disease Coronary artery disease (CAD), also called coronary heart disease (CHD), or ischemic heart disease (IHD), is a type of cardiovascular disease, heart disease involving Ischemia, the reduction of blood flow to the cardiac muscle due to a build-up ...

. Asian Indian men, Filipino men and Filipino women have a higher risk than white people. Young Hispanic women who have a heart attack have a higher mortality rate than young Hispanic men. They have a higher mortality rate than young Black adults and young white adults.

Research directions

Further research directions in preventing and treating coronary artery disease include: * Cellular Basis of Heart Failure * Genetics and Heart Failure * Sex and Heart Failure * Regenerative Therapies

In history

Coronary occlusion was first discussed in 1910 by Sir William Osler who discussed coronary occlusion during the Lumleian Lectures. In 1912, James Herrick published an article in

JAMA ''JAMA'' (''The Journal of the American Medical Association'') is a peer-reviewed medical journal published 48 times a year by the American Medical Association. It publishes original research, reviews, and editorials covering all aspects of b ...

documenting his findings on coronary occlusion in animals. According to Robert K. Massie's '' Nicholas and Alexandra: The Fall of the Romanov Dynasty'',

Tsar Nicholas II Nicholas II (Nikolai Alexandrovich Romanov; 186817 July 1918) or Nikolai II was the last reigning Emperor of Russia, King of Congress Poland, and Grand Duke of Finland from 1 November 1894 until his abdication on 15 March 1917. He married ...

may have suffered a coronary occlusion right before he was toppled from his throne during the Russian Revolution in 1917. Massie, Robert K. (2012), '' Nicholas and Alexandra: The Fall of the Romanov Dynasty''. New York, The Modern Library, p. 433. . Accessed 2016-11-19. Originally published in 1967 by Artheneum (United States) as ''Nicholas and Alexandra: An Intimate Account of the Last of the Romanovs and the Fall of Imperial Russia''. . Coroners cited a coronary occlusion as the cause of death for Mongomery Clift.

References

{{reflist Heart diseases