Chapter 14: The Heart and Heart Disease

Flashcards covering heart anatomy, chambers, valves, conduction system, cardiac cycle, diagnostic methods, and various heart diseases based on Chapter 14 lecture notes.

Circulation

A continuous one-way circuit of blood through the blood vessels.

Apex

The pointed inferior portion of the heart that points to the left.

Base

The broad superior portion of the heart where large vessels are attached.

Endocardium

A thin layer of epithelial cells that lines the heart’s interior and forms the flaps of heart valves.

Myocardium

The muscle layer of the heart wall.

Epicardium

The serous membrane forming the outermost layer of the heart, also considered the visceral layer of the pericardium.

Pericardium

The sac that encloses the heart, consisting of an outer parietal layer and an inner visceral layer (epicardium).

Intercalated Disks

Modified plasma membranes in the myocardium that firmly attach adjacent cells and allow for the rapid transfer of electrical impulses.

Pulmonary circuit

The right side of the heart that pumps blood low in oxygen into the lungs.

Systemic circuit

The left side of the heart that pumps oxygenated blood through the body.

Right atrium

The chamber that receives blood low in oxygen returning from the body via the superior and inferior vena cava.

Pulmonary arteries

Vessels that carry low oxygenated blood from the right ventricle away from the heart to the lungs.

Left ventricle

The chamber with the largest muscle wall that pumps blood through the aorta into the body and forms the entire apex of the heart.

Aorta

The body’s largest artery.

Interventricular Septum

The wall that separates the two ventricles of the heart.

Atrioventricular (AV) Valves

The valves located between the atria and the ventricles.

Right AV valve

Also known as the Tricuspid valve; it has three cusps and prevents backflow into the right atrium when the right ventricle contracts.

Left AV Valve

Also known as the Mitral Valve or Bicuspid; it has two cusps and is located between the left atrium and left ventricle.

Chordae Tendinae

Thin fibrous threads attached to papillary muscles in the ventricle walls that stabilize valve flaps to prevent backflow.

Semilunar Valves

The exit valves of the heart, named for their shape, including the pulmonary and aortic valves.

Coronary circulation

The system of arteries and veins that supplies blood to and from the myocardium.

Systole

The action or contraction phase of the cardiac cycle.

Diastole

The resting or relaxation phase of the cardiac cycle.

Cardiac cycle

The complete sequence of heart contraction and relaxation, lasting approximately $0.8\,\text{seconds}$.

Cardiac Output (CO)

The volume of blood pumped by each ventricle in $1\,\text{minute}$; calculated as $CO = HR \times SV$.

Stroke Volume (SV)

The volume of blood ejected from the ventricle with each beat.

Sinoatrial (SA) node

Also known as the Pacemaker, located in the upper wall of the right atrium, it initiates the heartbeat.

Atrioventricular bundle

Also known as the Bundle of His; it is located at the top of the interventricular septum and branches into the walls of the ventricles.

Vagus Nerve (CN X)

The part of the parasympathetic nervous system that decreases the heart rate to return it to normal.

Bradycardia

A heart rate of less than $60/\text{min}$.

Tachycardia

A heart rate of greater than $100/\text{min}$.

Stenosis

The narrowing of a valve opening.

Auscultation

Listening to heart sounds using a stethoscope.

Electrocardiograph (EKG/ECG)

A device that records the electrical activity of the heart.

Angioplasty

The surgical formation or molding of a vessel, often involving a catheter with a balloon or stent to open an occluded coronary artery.

Arrhythmia

An abnormal rhythm of the heartbeat.

Fibrillation

A rapid, wild, and uncoordinated heartbeat.

Foramen ovale

A small hole in the atrial septum used in fetal circulation to bypass the lungs.

Ductus arteriosus

A fetal vessel connecting the aorta and the pulmonary artery to bypass the lungs.

Tetralogy of Fallot

A condition involving four congenital defects: pulmonary artery stenosis, interventricular septal defect, aortic displacement to the right, and right ventricular hypertrophy.

Rheumatic Heart Disease

Damage to heart valves caused by rheumatic fever following a streptococcus infection.

Atherosclerosis

A form of coronary artery disease involving the thickening and hardening of arteries due to plaque (fatty material) and loss of elasticity.

Ischemia

A lack of blood supply to an area, caused by suppression.

Myocardial Infarction (MI)

A heart attack; a life-threatening occlusion of a coronary artery (thrombosis) leading to necrosis (death) of the muscle tissue.

Angina Pectoris

Discomfort in the chest and left arm due to inadequate blood flow to the heart muscle, typically lasting less than $15\,\text{minutes}$.

Congestive Heart Failure (CHF)

A condition where the heart is unable to pump enough blood, leading to fluid backup in the lungs, legs, feet, liver, and abdomen.

C-reactive protein (CRP)

A blood marker produced in the liver in response to chronic inflammation; indicates high risk for heart disease.

Cardioversion

A treatment for arrhythmias involving shocking the heart to restore normal rhythm.

Coronary artery bypass graft (CABG)

A surgical procedure where arteries harvested from other body parts are grafted to bypass an occluded coronary artery.