Cardiovascular System: Heart - Unit 8 Overview, Lecture notes of Anatomy

Download Cardiovascular System: Heart - Unit 8 Overview and more Lecture notes Anatomy in PDF only on Docsity!

Cardiovascular

System- Heart

Miss Wheeler Unit 8

Overview

CARDIOVASCULAR SYSTEM

“heart” “vessels”

Made up of heart, blood

vessels, and blood

The right side of

the system

deals with

deoxygenated

blood.

The left side of

the system

deals with

oxygenated

blood.

How Does It Work?

The Heart

› Hollow organ, about

the size of your fist

› Made of muscle to

pump blood

› Surrounded by

pericardium - fluid

filled sac

General Structure Veins bring blood to the heart Arteries bring blood away from the heart Atria are the upper 2 chambers Ventricles are the lower 2 chambers

External Structure

Superior Vena Cava Right Pulmonary Artery Right Pulmonary Veins Right Atrium Right Ventricle Inferior Vena Cava Left Pulmonary Artery Left Pulmonary Artery Left Pulmonary Veins Left Atrium Left Ventricle Apex Aorta

Valves

Atrioventricular Valves guard the entrances of

ventricles.

› Tricuspid valve- between atria and ventricle

entrance on the right side. Prevents blood from

washing back into the right atrium.

› Bicuspid valve (Mitral valve)- between atria and

ventricle entrance on the left side. Prevents

oxygenated blood from re-entering left atrium

Semilunar Valves guard the exits of the ventricles.

› Pulmonary semilunar valve- located between

right ventricle exit and pulmonary artery.

› Aortic semilunar valve- located between left

ventricle exit and the aorta.

Blood Flow

https://www.youtube.com/watch?v=7XaftdE_h

Sinotrial (SA) Node

› At the top of the

heart

› Acts as a

pacemaker

› Sends impulse for the

atria to contract and

start pumping blood

SA Node

Beating Heart

blood from

the body

blood

from the

lungs

The atria contract at the same time:

2. The atria then contract

and the valves open to

all blood into the

ventricles.

1. The heart beat begins

when the heart muscles

relax and blood flows into

the atria.

EKG (Electrocardiogram)

› Your heart sends an electrical impulse through it

each time it beats.

› An EKG measures those impulses in 2 waves (atria

contracting and ventricles contracting)

P wave- Atria contract QRS wave- Ventricles contract T wave- Ventricles relax Time Voltage https://www.youtube.com/watch? v=v3b-YhZmQu

Arrhythmia

Any change in

normal electrical

impulses of the heart

Tachycardia Fibrillation Bradychardia Normal EKG -more than 100 beats/ min -lack of blood flow to heart -less than 60 beats/min