Dictionary

cardiology The study and treatment of heart disorders.

cardiologist A physician who specializes in treating heart disorders.

cardiac ventricle See ventricle, heart.

cardiac tamponade See tamponade, cardiac.

cardiac septum The dividing wall between the right and left sides of the heart. That portion of the septum that separates the two upper chambers (the right and left atria) of the heart is termed the atrial (or interatrial) septum; the portion that lies between the two lower chambers (the right and left ventricles) of…

cardiac output The amount of blood the heart pumps through the circulatory system in a minute. The amount of blood put out by the left ventricle of the heart in one contraction is called the stroke volume. The stroke volume and the heart rate determine the cardiac output. A normal adult has a cardiac output…

cardiac muscle A type of muscle tissue that is found only in the heart and is distinguishable from the two other forms of muscle, smooth muscle (that moves internal organs, such as the bowels, and vessels, such as the artery walls) and skeletal muscle (that powers joints). Cardiac muscle is responsible for pumping blood throughout…

cardiac index A cardiodynamic measure based on the cardiac output, which is the amount of blood the left ventricle ejects into the systemic circulation in one minute, measured in liters per minute (l/min). Cardiac output is indexed to a patient’s body size by dividing by the body surface area to yield the cardiac index.

cardiac defibrillator, implantable A device that is designed to be put in the body to recognize certain types of abnormal heart rhythms (arrhythmias) and correct them by delivering precisely calibrated and timed electrical shocks to restore a normal heartbeat. Defibrillators continuously monitor the heart rhythm in order to detect overly rapid life-threatening arrhythmias, such as…

cardiac conduction system The electrical conduction system that stimulates the heart to contract and pump blood. This system generates electrical impulses and conducts them throughout the muscle of the heart. Among the major elements in the cardiac conduction system are the sinoatrial node, the atrioventricular (AV) node, and the autonomic nervous system. See also atrioventricular…

Cardiac arrest is a medical emergency that occurs when the heart suddenly stops beating effectively, leading to the cessation of blood flow to the brain and other vital organs. This results in a loss of consciousness and the absence of a pulse. If not treated immediately, cardiac arrest can lead to death within minutes. Causes…

cardiac arrest A heart attack in which the heart suddenly stops pumping sufficient blood. A cardiac arrest that results in the death of heart muscle is referred to as a myocardial infarction. See also myocardial infarction, acute.