Cardiovascular Health Glossary

  • Aneurysm —weak, bulging area of an artery that is prone to a leak or rupture
  • Angina —chest pain caused by insufficient blood flow to the heart
  • Angiography —diagnostic procedure that produces images of large and medium-sized arteries throughout the body
  • Aorta —the largest of the body’s arteries; blood flows from the heart, through the aorta, to the rest of the body
  • Arrhythmias —abnormal pattern of electrical conduction through the heart
  • Artery —blood vessel that carries blood away from the heart
  • Arterioles —branches of smaller arteries that connect the arterial system to the capillaries
  • Atherosclerosis —a disease process characterized by a buildup of fatty deposits and cellular debris inside artery walls that may impede blood flow
  • Atrioventricular (AV) Node —mass of conducting tissue in the lower right atrium that slows the electrical impulses as they pass from the atria to the bundle of His in the ventricles
  • Atrioventricular (AV) Valves —one-way valves located between the atria and ventricles
  • Atria —upper chambers of the heart, which collect blood from the veins
  • Bundle of His —cardiac fibers that conduct electrical impulses from the atria into the ventricles
  • Bradycardia —slow cardiac rate defined as less than 60 beats/minute
  • Capillaries —the smallest, most thinly-walled blood vessels; site of oxygen, nutrient, and waste exchange between blood and body tissues
  • Cardiac Circulation —also called coronary circulation; flow of blood through blood vessels supplying the heart muscle
  • Cardiovascular Disease —a collection of conditions that affect the heart and blood vessels
  • Conduction System —a network of specialized cardiac tissue that initiates and transmits electrical signals in the heart
  • Coronary Artery Disease (CAD, Coronary Heart Disease)—atherosclerotic blockage of arteries that feed that heart muscle; can lead to angina or heart attack
  • Coronary Sinus —a large vein that empties blood from the coronary circulation into the right atrium
  • Diastole —relaxation of the ventricles, during which time they fill with blood
  • Doppler Ultrasound —echocardiographic technique that uses color coding to illustrate the direction and velocity of blood flow through the heart chambers and vessels
  • Duplex Venous Ultrasound —noninvasive vascular study that uses ultrasound technology to visualize the flow of blood in veins
  • Echocardiography —test that using ultrasound technology to produce moving images of chambers, valves, and blood flow of the heart
  • Electrocardiogram —test used to examine the rhythm and electrical activity of the heart
  • Electrophysiology Study —test used to assess electrical conduction abnormalities that increase the risk of life threatening arrhythmias; often used in preparation for the implantation of an artificial pacemaker
  • Embolism —sudden obstruction of a blood vessel by a clot, atherosclerotic plaque, air bubble or other object circulating in the blood
  • Endocardium —innermost layer of the heart; forms continuous extension of endothelium lining the blood vessels
  • Endothelium —innermost layer of blood vessels made of up a single continuous sheet of endothelial cells; initial site of atherosclerosis
  • Fatty Streaks —build up of fatty particles in the endothelium
  • Gap Junctions —electrical synapses in the heart muscle
  • Glucose Intolerance —ineffective control of blood sugar levels usually due to insulin resistance; risk factor for type 2 diabetes
  • Heart Attack —also called myocardial infarction; death of heart muscle cells due to a sustained lack of oxygen
  • Heart Failure —a condition in which the heart is incapable of pumping sufficient blood to meet the needs of the body
  • Hemoglobin —protein in red blood cells that allows them to efficiently absorb, transport, and release oxygen throughout the body
  • High-density Lipoproteins —protein-containing particles that carry cholesterol and other fats from blood vessels to the liver; high levels are protective against atherosclerosis
  • Infarction —death of tissue due to sustained lack of oxygen
  • Insulin Resistance —reduced sensitivity to insulin; hallmark of glucose intolerance and type 2 diabetes
  • Intima —inner layer of arteries that make up the endothelium; initial site of atherosclerosis
  • Ischemia —inadequate oxygen supply to a tissue
  • Leukocytes —also called white blood cells; active in the body’s immune system
  • Low-density Lipoproteins —protein-containing particles that carry cholesterol and other fats from the liver to cells throughout the body; high levels contribute to atherosclerosis
  • Myocardium —heart muscle
  • Myocardial Infarction —also called heart attack; death of heart muscle cells due to a sustained lack of oxygen
  • Myocardial Ischemia —inadequate oxygen supply to the myocardium; occurs when the demand for oxygen exceeds its supply
  • Myocardial Perfusion Imaging —imaging procedure that uses radioactive isotopes to assess how well blood is reaching the heart muscle
  • Oxidation —a common chemical reaction involving oxygen; lipids in the endothelium become oxidized as part of the atherosclerotic process
  • Pacemaker —conducting tissue that spontaneously initiates each cardiac cycle, setting the pace of the heart; normally the sinoatrial (SA) node; artificial pacemaker is an implantable device that paces the heart when its natural pacemaker fails
  • Pericardium —membrane surrounding the heart
  • Peripheral Artery Disease (PAD)—atherosclerosis in arteries that carry blood to the legs
  • Plaque —an atherosclerotic lesion
  • Plasma —liquid component of blood; composed primarily of water; contains electrolytes, proteins, nutrients, waste products, hormones, and drugs
  • Platelets —blood component consisting of cellular remnants that aid in blood clot formation
  • Pulmonary Arteries —transport deoxygenated blood from the right ventricle to the lungs
  • Pulmonary Circulation —flow of blood from the right ventricle of the heart through the lungs and into the heart’s left atrium
  • Pulmonary Veins —transport oxygenated blood from the lungs into the left atrium
  • Purkinje Fibers —conducting tissue that carries electrical impulses from the bundle of His to the myocardium of the ventricles
  • Red Blood Cells —cells that carry oxygen and carbon dioxide throughout the body
  • Semilunar Valves —located at the base of the pulmonary artery and aorta allowing blood to flow to the pulmonary and systemic circulation respectively; prevent backflow of blood into the ventricles
  • Septum —muscular wall separating the left and right sides of the heart
  • Sinoatrial (SA) Node —also known as a pacemaker; mass of conducting tissue in the upper right atrium that normally sets the pace of the heart
  • Stroke —also known as cerebral infarction or cerebrovascular accident (CVA); death of brain cells due to sustained lack of oxygen
  • Systole —contraction of the ventricles, during which blood is ejected from the heart
  • Systemic Circulation —flow of blood throughout the entire body, with the exception of the lungs
  • Tachycardia —excessively rapid heart rate; usually defined as more than 100 beats/min at rest
  • Thrombosis —development or presence of a blood clot
  • Triglycerides —the chemical form in which most fat is stored in the body
  • Veins —blood vessels that return blood to the heart
  • Venae Cavae —2 large veins carrying blood directly to the right atrium of the heart
  • Venography —uses injected dyes and x-rays to examine the interior of veins
  • Ventricle —chamber of the heart that receives blood from the atrium and pumps it into the arteries
  • White Blood Cells —also called leukocytes; active in the body’s immune system

Last reviewed October 2016 by Michael Woods, MD