CardiologyFrom Wikipedia, the free encyclopediaThis article is about the medical specialty dealing with the heart. For the album by Good Charlotte, see Cardiology (album). For the medical journal, see Cardiology (journal).

Cardiology

Blood flow diagram of the human heart. Blue components indicate de-oxygenated blood pathways

and red components indicate oxygenated blood pathways.

System CardiovascularSubdivisions Interventional, Nuclear

Significant diseases

Heart disease, Cardiovascular disease, Atherosclerosis, Cardiomyopathy, Hypertension (High Blood Pressure)

Significant tests

Blood tests, Electrophysiology study, Cardiac imaging, ECG, Echocardiograms, Stress test

Specialist Cardiologist

Cardiology (from Greek καρδίᾱ kardiā, "heart" and -λογία -logia, "study") is a branch of medicine dealing with disorders of the heart be it human or animal. The field includes medical diagnosis and treatment of congenital heart defects, coronary artery disease, heart failure, valvular heart disease and electrophysiology. Physicians who specialize in this field of medicine are called cardiologists, a specialty of internal medicine. Pediatric cardiologists are pediatricians who specialize in cardiology. Physicians who specialize in cardiac surgery are called cardiothoracic surgeons or cardiac surgeons, a specialty of general surgery.

Contents 1 Specialization

o 1.1 Adult cardiology o 1.2 Pediatric cardiology

2 The heart 3 Disorders

o 3.1 Disorders of the coronary circulation o 3.2 Cardiac arrest o 3.3 Disorders of the myocardium (muscle of the heart) o 3.4 Disorders of the pericardium (outer lining of the heart) o 3.5 Disorders of the heart valves o 3.6 Congenital heart defect o 3.7 Diseases of blood vessels (vascular diseases) o 3.8 Procedures to counter coronary artery disease o 3.9 Devices used in cardiology o 3.10 Diagnostic tests and procedures

4 Cardiologists 5 Journals 6 Associations 7 See also 8 References 9 External links

SpecializationAll cardiologists study the disorders of the heart, but the study of adult and child heart disorders are through different training pathways. Therefore, an adult cardiologist (often unqualified and called just "cardiologist") is inadequately trained to take care of children, and pediatric cardiologists are inadequately trained to take care of adults. The surgical aspects are not included in cardiology and are in the domain of cardiothoracic surgery. For example, coronary artery bypass surgery (CABG) and cardiopulmonary bypass are both surgical procedures performed by surgeons, not cardiologists.

Adult cardiology

Cardiology is a specialty of internal medicine. To be a cardiologist in the United States, a three-year residency in internal medicine is followed by a three-year fellowship in cardiology. It is possible to specialize further in a sub-specialty. Recognized sub-specialties in the United States by the ACGME are:[citation needed]

Cardiac electrophysiology : Study of the electrical properties and conduction diseases of the heart.

Echocardiography : The use of ultrasound to study the mechanical function/physics of the heart.

Interventional cardiology : The use of catheters for the treatment of structural and ischemic diseases of the heart.

Nuclear cardiology : The use of nuclear medicine to visualize the uptake of an isotope by the heart using radioactive sources.

Recognized subspecialties in the United States by the American Osteopathic Association Bureau of Osteopathic Specialists (AOABOS) include:[1]

Clinical cardiac electrophysiology Interventional cardiology

Pediatric cardiology

Pediatric cardiology is a specialty of pediatrics. To be a pediatric cardiologist in the United States, a three-year residency in pediatrics is followed by a three-year fellowship in pediatric cardiology.

The heart

Blood flow through the valvesMain articles: heart and human heart

As the center focus of cardiology, the heart has numerous anatomical features (e.g., atria, ventricles, heart valves) and numerous physiological features (e.g., systole, heart sounds, afterload) that have been encyclopedically documented for many centuries.

Disorders of the heart lead to heart disease and cardiovascular disease and can lead to a significant number of deaths: cardiovascular disease is the leading cause of death and caused 29.34% of all deaths in 2002.[citation needed]

The primary responsibility of the heart is to pump blood throughout the body. It pumps blood from the body — called the systemic circulation — through the lungs — called the pulmonary circulation — and then back out to the body. This means that the heart is connected to and affects the entirety of the body. Simplified, the heart is a circuit of the

Circulation. While plenty is known about the healthy heart, the bulk of study in cardiology is in disorders of the heart and restoration, and where possible, of function.

The heart is a muscle that squeezes blood and functions like a pump. Each part of the heart is susceptible to failure or dysfunction and the heart can be divided into the mechanical and the electrical parts.

The electrical part of the heart is centered on the periodic contraction (squeezing) of the muscle cells that is caused by the cardiac pacemaker located in the sinoatrial node. The study of the electrical aspects is a sub-field of electrophysiology called cardiac electrophysiology and is epitomized with the electrocardiogram (ECG/EKG). The action potentials generated in the pacemaker propagate throughout the heart in a specific pattern. The system that carries this potential is called the electrical conduction system. Dysfunction of the electrical system manifests in many ways and may include Wolff–Parkinson–White syndrome, ventricular fibrillation, and heart block.

The mechanical part of the heart is centered on the fluidic movement of blood and the functionality of the heart as a pump. The mechanical part is ultimately the purpose of the heart and many of the disorders of the heart disrupt the ability to move blood. Failure to move sufficient blood can result in failure in other organs and may result in death if severe. Heart failure is one condition in which the mechanical properties of the heart have failed or are failing, which means insufficient blood is being circulated.

DisordersCardiology is concerned with the normal functionality of the heart and the deviation from a healthy heart. Many disorders involve the heart itself but some are outside of the heart.

Disorders of the coronary circulation

Coronary arteries labeled in red text and other landmarks in blue text.

Contrary to a basic understanding of the cardiovascular system, the heart cannot itself receive enough oxygen and nutrients from the blood it pumps and it must be supplied

with blood as if it were any other organ in the body. Unlike the systemic organs the heart receives perfusion in the phase of diastole rather than systole. This circulation of blood is called the coronary circulation. The coronary circulation consists of coronary arteries and coronary veins.

Disorders of the coronary circulation can have devastating effects to the heart since damage to the heart can reduce coronary circulation which causes further damage. A few examples are presented, as follows:

Acute coronary syndrome (ACS) Acute coronary syndrome is a broad term encompassing many acute myocardial infarction symptoms.

Angina pectorisAngina pectoris literally means "chest pain" that refers to pain caused by ischemia of the heart.

AtherosclerosisAtherosclerosis is the condition in which an artery wall thickens as the result of a build-up of fatty materials (e.g., cholesterol). Atherosclerosis of a coronary artery leads to coronary heart disease.

Coronary heart diseaseCoronary heart disease is a general term for any reduction in coronary circulation. One such condition is atherosclerosis.

Myocardial infarction (a.k.a. heart attack) A myocardial infarction is the death of a part of the heart which is typically caused by a blockage of the coronary circulation or coronary heart disease.

RestenosisRecurrence of stenosis which would refer to a narrowing of a coronary artery in the context of the coronary circulation.

Cardiac arrest

A rhythm strip showing a couple beats of normal sinus rhythm followed by an atrial beat and asystole ("flatline").

Cardiac arrest refers to the cessation of normal systemic circulation due to failure in proper contraction of the heart. There are several conditions that can cause cardiac arrest.

Asystole ("flatline") 

Asystole refers to the absence of electrical activity of the heart and is sometimes referred to as a "flatline" because the electrocardiogram shows a solid line due to the absence of electrical activity.

Pulseless electrical activity (PEA) Pulseless electrical activity is when the electrocardiogram shows a rhythm that should produce a pulse but it does not. PEA is commonly caused by the 6 H's and 6 T's (see PEA article).

Pulseless ventricular tachycardiaPulseless ventricular tachycardia (VT) Is one classification of VT such that no pulse is felt because of an ineffective cardiac output which causes cardiac arrest.

Sudden cardiac deathSudden cardiac death is a concept of natural death rather than a specific medical condition. There are several causes of sudden cardiac death and it is distinct from cardiac arrest.

Ventricular fibrillationVentricular fibrillation is fibrillation of the ventricles of the heart. Rhythmic contraction is necessary for efficient movement of blood, and fibrillation disrupts this rhythm sufficiently to cause cardiac arrest.

Treatment of cardiac arrest includes cardiopulmonary resuscitation (CPR) and defibrillation depending on the exact cause of cardiac arrest.

Disorders of the myocardium (muscle of the heart)

The diagram shows a healthy heart (left) and one suffering from right ventricular hypertrophy (right).

A man with congestive heart failure and marked jugular venous distension. External jugular vein marked by an arrow.Cardiomyopathy

Cardiomyopathy is a deterioration of the myocardium. Ischemic cardiomyopathy Cardiomyopathy causing ischemia of the heart due to coronary artery disease.Nonischemic cardiomyopathy Cardiomyopathy not caused by ischemia of the heart. Amyloid cardiomyopathyCardiomyopathy caused by amyloidosis.Hypertrophic cardiomyopathy (HCM) Cardiomyopathy caused by hypertrophy of the heart. Hypertrophic obstructive cardiomyopathy (HOCM) (Idiopathic hypertrophic subaortic stenosis (IHSS))