Electrocardiogram (ECG, EKG) Glossary of Terms

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Abnormal: Outside the expected norm, or uncharacteristic of a particular patient.

Acute: Of abrupt onset, in reference to a disease. Acute often also connotes an illness th...

Acute myocardial infarction: A heart attack.

Anatomy: The study of human or animal form, by observation or examination of the living be...

Angina: Chest pain due to an inadequate supply of oxygen to the heart muscle. The pain is ...

Anxiety: A feeling of apprehension and fear, characterized by physical symptoms such as pa...

Aorta: The largest artery in the body, the aorta arises from the left ventricle of the he...

Artery: A vessel that carries blood high in oxygen content away from the heart to the far...

Atherosclerosis: A process of progressive thickening and hardening of the walls of medium-...

Atria: The plural of atrium.

Atrial: Pertaining to the atria, the upper chambers of the heart, as in atrial fibrillatio...

Atrial fibrillation: An abnormal and irregular heart rhythm in which electrical signals ar...

Atrial flutter: Well-organized but overly rapid contractions of the atrium of the heart (u...

Atrioventricular node: The electrical relay station between the upper and lower chambers o...

Atrium: An entry chamber. On both sides of the heart, the atrium is the chamber that leads...

AV node: Atrioventricular node.

Axilla: Armpit.

Baseline: Information or data gathered at the beginning of a period from which variations ...

Blood pressure: The blood pressure is the pressure of the blood within the arteries. It is...

Bradycardia: A slow heart rate, usually defined as less than 60 beats per minute.

Brain: The portion of the central nervous system that is located within the skull. It func...

Breast bone: Familiar name for the sternum, the long flat bone in the middle of the front ...

Carbon dioxide: A gas which is the byproduct of cellular metabolism and which collects in ...

Chest: The area of the body located between the neck and the abdomen. The chest contains t...

Chest pain: Pain in the chest that can be a result of many things, including angina, heart...

Circulatory: Having to do with circulation, the movement of fluid in a regular or circuito...

Contraction: The tightening and shortening of a muscle.

Defibrillator: A device that corrects an abnormal heart rhythm by delivering electrical sh...

ECG: Electrocardiogram.

Electrocardiogram: A recording of the electrical activity of the heart. Abbreviated ECG an...

Fibrillation: In cardiology, an abnormal and erratic twitching of the heart muscle.

Flutter: Flutter is a rapid vibration or pulsation. The difference between flutter and fib...

Heart: The muscle that pumps blood received from veins into arteries throughout the body. ...

Heart attack: The death of heart muscle due to the loss of blood supply. The loss of bloo...

Heart block: A blockage in the conduction of the normal electrical impulses in the heart. ...

Heart disease: Any disorder that affects the heart. Sometimes the term "heart disease" is ...

Heart failure: Inability of the heart to keep up with the demands on it and, specifically...

Heart muscle: A type of muscle with unique features only found in the heart. The heart mus...

Heart rate: The number of heartbeats per unit of time, usually per minute. The heart rate ...

Heart rhythm disorders: Abnormal rhythm of the heartbeat due to irregularities in transmis...

Infarction: The formation of an infarct, an area of tissue death, due to a local lack of o...

Inferior: In anatomy, below or toward the feet. As opposed to superior. The liver is infer...

Left atrium: The upper right chamber of the heart. The left atrium receives oxygenated blo...

Left ventricle: The left lower chamber of the heart that receives blood from the left atri...

Leg: In popular usage, the part of the body from the top of the thigh down to the foot, an...

Lightheadedness: A feeling you are "going to faint." Lightheadedness is medically distinc...

Limb: An arm or a leg.

Lungs: The lungs are a pair of breathing organs located with the chest which remove carbon...

Metabolism: The whole range of biochemical processes that occur within a living organism. ...

MPH: Master of public health, a degree designating successful training in analyzing past, ...

Muscle: Muscle is the tissue of the body which primarily functions as a source of power. T...

Muscular: Having to do with the muscles. Also, endowed with above average muscle developme...

Myocardial infarction: A heart attack. Abbreviated MI.

Nausea: Stomach queasiness, the urge to vomit. Nausea can be brought on by many causes, in...

Node: Literally a knot, a node is a collection of tissue. For example a lymph node, is a ...

Nurse: 1) A person trained, licensed, or skilled in nursing. 2) To feed an infant at the ...

Oxygen: The odorless gas that is present in the air and necessary to maintain life. Oxygen...

Pacemaker: A system that sends electrical impulses to the heart in order to set the hear...

Pain: An unpleasant sensation that can range from mild, localized discomfort to agony. Pa...

Palpitations: Unpleasant sensations of irregular and/or forceful beating of the heart. In ...

Pulmonary: Having to do with the lungs.

Pulmonary artery: One of the two vessels which are formed as terminal branches of the pulm...

QRS complex: The deflections in an electrocardiogram (EKG) tracing that represent the vent...

Right atrium: The right upper chamber of the heart. The right atrium receives deoxygenated...

Right ventricle: The lower right chamber of the heart that receives deoxygenated blood fro...

SA node: The SA node (SA stands for sinoatrial) is one of the major elements in the cardi...

Shock: In medicine, a critical condition that is brought on by a sudden drop in blood flow...

Shortness of breath: Difficulty in breathing. Medically referred to as dyspnea. Shortness ...

Shoulder: A structure made up of two main bones: the scapula (shoulder blade) and the hume...

Sinoatrial node: The heart's natural pacemaker, one of the major elements in the cardiac c...

Sinus: 1. An air-filled cavity in a dense portion of a skull bone. The sinuses decr...

Sinus bradycardia: A regular but unusually slow heart beat (50 beats/minute or less at res...

Sinus node: The sinus node is one of the major elements in the cardiac conduction system, ...

Sinus rhythm: The normal regular rhythm of the heart set by the natural pacemaker of the h...

Sinus tachycardia: Fast heartbeat (tachycardia) that occurs because of overly rapid firing...

Stage: As regards cancer, the extent of a cancer, especially whether the disease has spre...

Syncope: Partial or complete loss of consciousness with interruption of awareness of one...

Syndrome: A combination of symptoms and signs that together represent a disease process.

Tachycardia: A rapid heart rate, usually defined as greater than 100 beats per minute.

Vena cava: The superior vena cava is the large vein which returns blood to the heart from ...

Ventricle: A chamber of an organ. For example, the four connected cavities in the central ...

Ventricles: 1, The right ventricle and the left ventricle, the lower two chambers o...

Ventricular: Pertaining to the ventricles, the lower chambers of the heart, as in ventricu...

Ventricular fibrillation: An abnormal and irregular heart rhythm in which there are rapid ...

Ventricular tachycardia: An abnormal heart rhythm that is rapid and regular and that origi...