Med Term Cardiovascular System - HEART

What is the function of the heart?

Pump blood throughout the body

Where is the heart located?

Thoracic cavity

What is the mediastinum?

Space between the lungs where the heart is located

What is the pericardium?

Tough fibrous membrane that protects and separates the heart from other mediastinal structures

What is the pericardial cavity?

Space occupied by the heart within the mediastinum

What are the three layers of the heart from outer to inner?

Epicardium, Myocardium, Endocardium

What is the epicardium?

Outer layer of the heart

What is the myocardium?

Middle muscular layer responsible for contraction

What is the endocardium?

Inner layer lining the heart chambers and valves

What are the four chambers of the heart?

Right atrium, Left atrium, Right ventricle, Left ventricle

What separates the right and left atria?

Interatrial septum

What separates the right and left ventricles?

Interventricular septum

What is an atrioventricular (AV) valve?

Valve between an atrium and ventricle

What is the tricuspid valve?

Right AV valve between the right atrium and right ventricle

What is another name for the bicuspid valve?

Mitral valve

What does the mitral valve separate?

Left atrium and left ventricle

What are the two semilunar valves?

Pulmonary valve and Aortic valve

What does the pulmonary valve separate?

Right ventricle and pulmonary trunk

What does the aortic valve separate?

Left ventricle and aorta

What are the two circulatory circuits?

Pulmonary circuit and systemic circuit

What is the function of the pulmonary circuit?

Transport blood to and from the lungs for gas exchange

What is the function of the systemic circuit?

Deliver oxygenated blood to body tissues and return deoxygenated blood to the heart

What vessels carry deoxygenated blood to the right atrium?

Superior and inferior vena cava

What valve moves blood from the right atrium to the right ventricle?

Tricuspid valve

What vessel carries blood from the right ventricle to the lungs?

Pulmonary trunk

What are the only arteries that carry deoxygenated blood?

Pulmonary arteries

Where does gas exchange occur in the lungs?

Pulmonary capillaries

What vessels carry oxygenated blood from the lungs to the heart?

Pulmonary veins

What are the only veins that carry oxygenated blood?

Pulmonary veins

What chamber receives oxygenated blood from the lungs?

Left atrium

What valve moves blood from the left atrium to the left ventricle?

Mitral valve

What vessel carries blood from the left ventricle to the body?

Aorta

What is diastole?

Relaxation phase when chambers fill with blood

What happens to the AV valves during diastole?

They are open

What is systole?

Contraction phase when ventricles eject blood

What happens to the AV valves during systole?

They close

What valves are open during ventricular systole?

Semilunar valves

What blood vessels supply the myocardium?

Coronary arteries and coronary veins

Why do myocardial cells need their own blood supply?

To receive oxygen and nutrients and remove waste products

What type of muscle makes up the heart?

Cardiac muscle tissue

How many nuclei do cardiac muscle cells usually contain?

One to two nuclei

What connective tissue surrounds cardiac muscle cells?

Endomysium

What organelle is abundant in cardiac muscle cells?

Mitochondria

What are pacemaker cells?

Cells that spontaneously depolarize and initiate heartbeats

What is depolarization?

Change in membrane potential from negative toward positive

Why can pacemaker cells fire on their own?

They have leaky sodium and potassium channels

What is the natural pacemaker of the heart?

Sinoatrial (SA) node

Where is the SA node located?

Right atrium

What is the function of the SA node?

Initiates electrical impulses that set heart rhythm

What are gap junctions?

Connections that allow electrical impulses to pass between cardiac cells

What is the atrioventricular (AV) node?

Structure that delays electrical impulses before ventricular contraction

Why does the AV node delay the impulse?

Allows atria to finish contracting before ventricles contract

What is another name for the atrioventricular bundle?

Bundle of His

What is the function of the Bundle of His?

Carries impulses from the AV node toward the ventricles

What are Purkinje fibers?

Fibers that distribute impulses throughout the ventricles

How do ventricles contract?

From the bottom upward

What is arrhythmia?

Abnormal heart rhythm

What is hypertension?

High blood pressure

What does occlude mean?

To block or close tightly

What is auscultation?

Listening to heart sounds

What is diaphoresis?

Excessive sweating

What is a sphygmomanometer?

Instrument used to measure blood pressure

What does congenital mean?

Present at birth

What is a bruit?

Abnormal blowing or swishing sound heard during auscultation

What is an aneurysm?

Localized dilation of a blood vessel wall

What is a stethoscope?

Instrument used to listen to heart and lung sounds

What is syncope?

Brief loss of consciousness or fainting

What is a myocardial infarction (MI)?

Heart attack caused by loss of blood flow to heart tissue

What is cardiomyopathy?

Abnormal enlargement or disease of the heart muscle

What is hypertrophic cardiomyopathy?

Abnormal thickening of the myocardium

What is dilated cardiomyopathy?

Enlargement of the ventricles

What is arrhythmogenic cardiomyopathy?

Inherited disease causing abnormal heart rhythms

What is restrictive cardiomyopathy?

Condition causing stiffening or scarring of the myocardium

What is heart failure?

Inability of the heart to pump enough blood to meet the body's needs

What is another name for heart failure?

Congestive heart failure (CHF)

What are two common symptoms of CHF?

Shortness of breath and swelling of lower extremities

What is valvular heart disease?

Disease affecting proper opening and closing of heart valves

What is mitral valve prolapse (MVP)?

Failure of the mitral valve to close completely causing regurgitation

What is aortic stenosis?

Narrowing and hardening of the aortic valve

What causes an aneurysm?

Weakening and thinning of a vessel wall

What is an aortic dissection?

Blood leaking between layers of the aortic wall