Cardiovascular System

pericardium

pericardium

a thin sac that protects the heart

epicardium

the outer layer of the heart

myocardium

heart muscle

endocardium

the innermost layer, which lines the heart’s chambers and covers its valves

atrium

atria (plural)

• two upper chambers of the heart

• have thin wall, serve as reservoirs for blood

ventricles - ventriculi

• two lower chambers of the heart

• have thick wall, pump blood throughout the body

superior vena cava

the vein that carries blood from the upper body to the right atrium

inferior vena cava

the vein that carries blood from the lower body to the right atrium

pulmonary artery

the blood vessel where blood is pushed through to the lungs

• tricuspid valve: separate the right atrium from the right ventricle, and have 3 cups

• mitral (bicuspid) valve: separate the left atrium from the left ventricle

What are the names of the 2 atrioventricular valves?

What do they separate?

• pulmonic valve: separate the right ventricle from the pulmonary artery

• aortic valve

What are the names of the 2 semilunar valves?

What do they separate?

sinoatrial node (SA)

the heart’s pacemaker

AV node → AV bundle → bundle of His → Purkinje fibers

Thr route of the impulses of the heart

• Slow heart rate

• Reduce impulse conduction

• Dilate coronary arteries

What is the parasympathetic action on the heart?

• Increase heart rase

• Increase impulse conduction

• Constricts and dilates the coronary arteries

What is the sympathetic action on the heart?

Systole

The phase when the ventricles contract and send blood on an outward journey to the aorta and the pulmonary artery

Diastole

The phase when the heart relaxes and fills with blood

During this phase, the mitral and tricuspic valves are open, the aortic and pulmonic valves are closed

• Ventricular filling: 70% of blood in the atria drains into the ventricles as a result of gravity

• Atrial contraction: accounts for the 30% remaining of blood that passes into the ventricles

What are the two parts of diastole?

Circumplex artery of the left coronary artery

Which blood vessel supplies blood to the left atrium and the posterior walls of the left ventricle?

Anterior intraventricular artery of the left coronary artery

Which blood vessel supplies blood to the intraventricular septum and anterior walls of both ventricles?

Right coronary artery

Which blood vessels supllies blood to the right atrium (include SA and AV nodes), part of the left atrium, most of the right ventricle and the inferior part of the left ventricle?

S1 (the lub of lub-dub)

What is the name of the first heart sound when the tricuspid and mitral valves snap closed?

Cardiac output

The amount of blood pumped out by the heart in 1 minute

Stroke volume

• The amount of blood ejected with each heartbeat

• Depends on contractility, preload, afterload

Preload

• The stretching of muscle fibers in the ventricles

• The more the muscles stretch, the more forcefully they contract during systole

Afterload

The pressure the ventricular muscles must generate to overcome the higher pressure in the aorta

• Arteries, arterioles

• Veins, venules

• Capillaries

What does the peripheral vascular system consist of?

Carry oxygen-rich blood from the heart to the rest of the body

What is the role of nearly all arteries?

Carry oxygen-depleted blood to the lungs

What is the role of the pulmonary arteries?

Exchange of fluid, nutrients and metabolic wastes betwee blood and cells

What is the role of the capillaries?

Carrry oxygen-depleted blood

What is the role of nearly all veins?

Carry oxygen-rich blood from the lungs to the heart

What is the role of pulmonary veins?

• Blood pressure

• Pulse

What are the 2 vital signs that related to cardiovascular system?

Systolic blood pressure

• Blood pressure caused by contraction phase of the left ventricle of the heart

• Normal measurement: 120 mmHg

Diastolic blood pressure

• Blood pressure during the relaxation phase

• Normal measurement: 80 mmHg

Pulse pressure

The numerical difference between the systolic and diastolic blood pressure

Sphygmomanometer

An instrument that consists of an inflatable cuff, bulb and a gauge, which is designed to measure arterial blood pressure

Stethoscope

• An instrument used to auscultation of respiratory, cardiac, intestinal, uterine, fetal, arterial and venous sounds

• Consist of 2 earpieces that are connected flexible tubing to a diaphragm

Korotkoff sounds

The first faint sounds heard as the pressure in the cuff is released and blood begins to flow

• Korotkoff sounds

• The last sound heard before silence as blood flow

What are the two sounds that correspond to the systolic and diastolic pressures?

Murmur

A soft blowing or fluttering sound of cardiac and vascular origin

Bruit

An abnormal sound heard over arteries that indicates turbulent blood flow

Cyanosis

A bluish discoloration of the skin and mucous membrane that results from an excessive amount of deoxygenated hemoglobin in the blood or a structural defect in the Hb molecule

pallor

paleness

edema

the accumulation of abnormal amounts of fluid in the intercellular tissues, pericardial sac, pleural cavity, peritoneal cavity or joint capsules

Diaphoresis

Profuse perspiration associated with an elevated body temperature (excessive sweating)

Angina

Chest pain that last for several minutes due to an inadequate supply of oxygen and blood flow to the heart muscle

Activated partial thromboplastin time

The test to measure the time required for formation of a fibrin clot, requires a blood sample to evaluate all the clotting factors of the intrinsic pathway

Cardiac enzyme test

The test to determine if cardiac tissue has been damaged

Creatinine kinase and the isoenzyme CK-MB

Elevated levels of which enzyme confirm a myocardial infarction?

Cardiac troponin test

The most precise way to diagnose an myocardial infarction

Cardiac cathererization

A procedure in which a catheter is inserted into a large artery or vein and then threaded through the vessel to the patient’s heart. After injection of a radiopaque contrast medium, X-rays are taken to detect heart anomalies.

Angiocardiography

Create an X-ray of the heart and great vessels after injection of contrast medium into a blood vessel or one of the heart chambers

Angiography

Produce an X-ray of the blood vessels after injection of a radiopaque contrast medium

Radionuclide scan

A test that helps to measure heart function and damage

During this test, a mildly radioactive material is injected into the patient’s bloodstream → computer-generated pictures are used to locate the radioactive element in the heart

Thallium stress test

A test that helps diagnose coronary artery disease

The patient is given a thallium isotope IV after a treadmill stress test. The isotope doesn’t collect in areas of poor blood flow and damaged cells and show up as “cold spots” on a scanner

Electrophysiologic studies

An invasive tests that help diagnose conduction system disease and serious heart rhythm disturbance

The cardiologist induces a rhythm disturbance. After identifying the source of rhythm disturbance, the cardiologist either admisters medications or uses high-frequency waves to terminate the disturbance.

Pericardiocentesis

A procedure in which the pericardium cavity is punctured for the aspiration of fluid from the pericardial sac

Transesophageal echocardiography

A technique in which a probe is passed through the mouth and down the esophagus to study the structure and motion of the heart using an echo from the beams of ultrasonic waves.

Electrocardiogram (ECG)

A graphic record that is produced by an electrocardiograph and shows variation in electrical potential

Atrial depolarization

What does the P-wave represent on the ECG?

Electrical acitivity absence (for a brief period)

What does the PR interval represent on the ECG?

Ventricular depolarization

What does QRS complex represent on the ECG?

Repolarization of the ventricular muscle

What does the ST segment represent on the ECG?

The actual recovery

What does the T wave represent on the ECG?

Transthoracic echocardiography

A technique that is used to study the structure and motion of the heart by echo from ultrasonic waves directed through the chest wall

Arrythmia

Lack of normal heart rhythm

Atrial flutter

• Arrhythmia in which atrial rhythm is regular, but the rate is 250-400 beats/minute

• The flutter waves have a sawtooth appearance

• The ventricular rate is variable

Cardiac arrest

When the heart stops abruptly with an absence of blood pressure or pulse

Cardiac tamponade

Blood and fluid fills the pericardial space and presses against the heart, compressing the heart chambers and obstructing venous return to the heart

Cardiogenic shock

• Pump failure

• When > 40% of the heart muscle is damaged by a MI → heart can’t pump effectively and body tissues don’t receive the necessary amount of oxygen and nutrients

Hypotension

Blood pressure is below normal values

Hypovolemic shock

Reduced intravascular blood volume → circulatory dysfunction and inadequate blood flow to tissues

Pulmonary edema

An accumulation of excess fluid in the lungs

Ventricular aneurysm

An outpounching of the ventricular wall (commonly seen in the left ventricle)

Bradycardia

Slow heart beat (<60 beats/min)

Tachycardia

Resting heartbeat > 100 beats/min

Fibrillation

• An uncoordinated, irregular contraction of the heart muscle, which may originate in the atria or ventricles.

• Can lead to cardiac arrest if left untreated

Heart block

An impaired conduction of the heart’s electrical impulses at the AV node → lead to a slow heartbeat

Paroxysmal atrial tachycardia

An arrhythmia in which the atrial and ventricular rates are regular and exceed 160 beats/min → characterized by a sudden onset and termination

Premature atrial contraction

An arrhythmia characterized by premature abnormal-looking P-waves

Premature ventricular contraction

The QRS complex is premature, wide and distorted

Ventricular tachycardia

A potentially deadly arrhythmia in which QRS complexes are wide and bizzare and originate in the ventricles

Atrial septal defect

• Opening between two atria

• Blood shunt from left to right (because the LA has higher pressure than the RA) → overload on the right of the heart → enlarge right side to accomodate the increased volume

Coarctation of the aorta

Narrowing of the lumen (opening of the aorta) → high pressure above and low pressure below the stricture

Patent ductus arteriosus

When the passage between the aorta and pulmonary artery (that normally closes at birth) remains open and send oxygenated blood back to the lungs

Tetralogy of Fallot

Involve four major defects of the heart and great vessels, first describe by the French doctor Etienne Fallot

Ventricular septal defect

Opening between the two ventricles → allow blood to shunt between them

Degenerative heart disease

Progressive deterioration of heart structures, tissue and function

Coronary artery disease (CAD)

Arteries that serve the heart are obstructed or narrowed

Atherosclerosis

What is the most common cause of CAD?

Dilated cardiomyopathy

The heart dilates and takes on a round shape as a result of extensively damaged heart muscle fibers

Heart failure

When the heart can’t effectively pump blood and becomes congested with extra fluid

Hypertension

When the blood pressure is higher than normal values (>140/90 mmHg or >130/80 in patients with diabetes or CKD)

Pre-hypertensive

A patient which SBP = 120-139 and DBP = 80-89

Hypertrophic cardiomyopathy

Disproportionate thickening of the interventricular septum and ventricular walls

Myocardial infarction (heart attack)

Reduced blood flow through one of the coronary arteries → myocardial ischemia (lack of blood supply) and necrosis (tissue death)

Restrictive cardiomyopathy

Restricted ventricular filling (result of LV hypertrophy) and endocardial fibrosis

Endocarditis

Bacterial or fungal infection of the heart valves or endocardium

Myocarditis

Inflammation of the heart muscle that can be acute or long-term