Capillaries: Tiny blood vessels between arteries and veins that distribute oxygen rich blood to the body.

Cardiac:  To do with the heart.

Cardiac Arrest: When your heart stops beating.

Cardiomyopathy: Disease of the heart muscle, causing decreased functioning of the heart.

Cardiovascular Disease: Any disease that affects the heart and its circulation.

Cardioversion: Delivery of a shock to the heart to interrupt arrhythmias. Paddles on the chest or electrodes placed directly on the heart are used.

Cholesterol: A waxy substance that is produced by the human body. Cholesterol is found in animal fats (beef, chicken, pork), shellfish, and dairy products (butter, milk, cheese ,eggs). The body needs cholesterol to produce hormones. When too much cholesterol circulates in the blood, atherosclerosis (hardening of the arteries) occurs and an increased risk of heart attack.

Commotio Cortis: Is a disruption of heart rhythm that occurs as a result of a blow to the area directly over the heart (percordial region) at a critical time during the cycle of a heartbeat. It is a form of ventricular fibrillation, not mechanical damage to the heart muscle or surrounding organs, and not the result of heart disease. The fatality rate is about 65%. It can sometimes, but not always, be reversed by defibrillation.

Congenital: Present at birth.

Congenital Heart Disease: A heart defect present at birth. Congestive Heart Failure. A condition in which the heart cannot pump out all the blood. This can lead to an accumulation of blood in the vessels going into the heart and an accumulation of fluid in the body tissues. Excess blood can increase in the lungs blood vessels leading to fluid accumulation in the lungs which creates congestion. Also known as CHF

Coronary Artery: Either of the two arteries that originate in the aorta and supply blood to the heart.

Coronary Artery Disease:: Result of the build up of plaque deposits on the inner lining of the coronary arteries. Also known as CAD.

Coronary Heart Disease: The most common form of heart disease. This type of heart disease is caused by a narrowing of the coronary arteries that feed the heart. The result in not enough oxygen rich blood reaching the heart. Also known as CHD.

Coronary Spasm: Abnormal sustained constriction of a major coronary producing symptoms of ischemia.

Coronary thrombosis: Total blockage of the blood flow to the heart due to a blood clot in a coronary artery, also called a “heart attack” or “myocardial infarction.”

CPR: Cardio-Pulmonary Resuscitation. A life-saving emergency medical procedure for restoring normal heartbeat, through manual and continuous compressions on the chest of the victim.

Cyanosis: Due to an insufficient oxygen supply in the blood that would leave tissue appearing blue, first seen in lips and nails.