EKG CH 1

Review

Influences on heart size/ weight

age

body weight

build

physical exercise

heart disease

How many chambers does the heart have?

The heart has four chambers: two atria and two ventricles, which play a crucial role in blood circulation.

What are the 3 tissue layers

endocardium

myocardium

epicardium

Where does the heart sit?

Behind Sternum

What are the 4 valves of the heart?

The heart contains four valves: the tricuspid valve, the pulmonary valve, the mitral valve, and the aortic valve, which regulate blood flow through the heart.

How many phases does the cardiac cycle have?

The cardiac cycle consists of two main phases: diastole, when the heart muscle relaxes and fills with blood, and systole, when the heart muscle contracts and pumps blood out.

What is the pericardium?

The pericardium is a double-layered membrane that surrounds the heart, providing protection and anchoring it within the chest cavity while also allowing for movement during the heart's contractions.

What are the two layers of the pericardium called?

Parietal & Visceral

What layer is the Parietal pericardium?

The outer layer

What layer is the Visceral pericardium?

The inner layer that directly covers the heart.

What are the two Atrioventricular valves ?

The tricuspid and mitral (bicuspid) valves.

What are the two Semilunar Valves?

The aortic and pulmonary valves.

What are the Big Arteries & Veins

▪ Right coronary artery (RCA)
▪ Right marginal artery
▪ Posterior descending artery
▪ Left main coronary artery(LMCA)
▪ Left circumflex artery
▪ Left marginal artery
▪ Left anterior descending artery
▪ SA Node Artery
▪ AV Node Artery
▪ Posterior Descending

What is the main purpose of the Left Coronary Artery

Supplies oxygenated blood to its two primary
branches: the left anterior descending (LAD), which
is also called the anterior interventricular artery,
and the circumflex (Cx)

What si the purpose of the Right Coronary Artery

A branch of the RCA supplies the following structures:
▪ Right atrium
▪ Right ventricle
▪ Inferior surface of the left ventricle in about 85% of
individuals
▪ Posterior surface of the left ventricle in 85%
▪ Sinoatrial (SA) node in about 60%
▪ AV bundle in 85% to 90%

What are the steps for Electrical Conduction in the Heart?

1. SA nods depolarizes

2. Electrical activity goes rapidly to AV node via internodal pathways

3. Depolarization spreads more slowly across atria. Conduction slows through AV node

4. Depolarization moves rapidly through ventricular conducting system to the apex of the heart

5. Depolarization wave spreads upward from apex.

Systole

Working

Contracting

Top number