Anatomy and Function of the Cardiovascular System

Anatomy and Function of the Anatomy and Function of the Cardiovascular SystemCardiovascular System

The Central Role of the CV is to Distribute Oxygen to Cells

Left Ventricle

Right Ventricle

The Primary Organ of the CV System is the Heart, a Four-Chamber Pump That Provides the Driving Force for Blood Flow

The Flow of Blood From the Body to the Heart and Back Again

The Circulation Also Must Supply the Heart Muscle Itself

The Flow To and From the Heart Is Systematic

Atherosclerosis is Restricted Blood Flow Through the Coronary Arteries

Consequences of Disruption of Coronary Artery Flow

Thrombosis Myocardial Infarction…. “Heart Attack”

Coronary Bypass Surgery-Method to Circumvent Arterial Blockage and Restore Coronary Circulation

Arterial Graphs

Pacemaker Leads

Spontaneous Electrical Activity in the Heart

The electrical signals generated by the heart are what are referred to as an EKG or “electrocardiogram”

Signal Begins here

“Normal” EKG is an indication that all the tissues are properly conducting electrical impulses

There are a large number of departures from this normal-looking EKG that indicate tissue damage or dysfunction.

• Distorted QRS complex

• ST segment depression

PS vagus nerve

Sympathetic accelerator nerve

A-V Node

S-A Node

Heart Rate and Contractile Strength are Controlled by Input From Two Systems:Parasympathetic and Sympathetic

Spinal Cord

Effects of the Parasympathetic and Sympathetic on Cardiovascular Function

PS Vagus

Heart Heart Rate Blood pumped from the Heart & Blood Pressure

Sympathetic

Heart Heart Rate Blood pumped from the Heart & Blood Pressure

Arterioles Constriction

Blood Pressure

“Fight or Flight”

As vessels get further from the heart, they decrease in size but increase in importance.

Constriction Versus Capacitance Vessels

The Ability to Constrict Arterioles is Vital for Distributing Blood to Various Tissues

Critical because there is a limited supply of blood and competition exists between tissues

ARTERIOLES ARE THE PRIMARY “FLOW REGULATING” VESSELS

Capillaries assist in this process by opening/closing in response to different metabolic conditions.

This is also the site where fuel and gas exchange takes place

CapillariesArterioles

Capillaries are the smallest elements of the “plumbing system”

Their density is a function of the need of the specific tissue for oxygen e.g. fast twitch versus slow twitch muscle

Transfer of fuel,O2,CO2 etc. to and from blood and cells is accomplished at the capillaries via a process called “diffusion” which requires a difference in concentration between the two compartments.

Cell

Capillary

i.e. Concentration blood O2 > Concentration cell O2 = flow from blood to cell