CADIOVASCULAR SYSTEM

Submitted by-Munesh Kumar Singh

M.Tech.(ICE) Ist yrReg.No-136323

Human body Subsystem. Cardiovascular system. Structure and Functioning of Heart. Blood flow. Cardiac cycle Electrical activity

contents:

Biochemical System Cardiovascular System Respiratory System Muscular System

Human Body Subsystem

Communication and transportation -Blood -Cardiovascular System -Nervous System -Lymphatic System Intake and waste Disposal -Respiratory System -Digestive System -Urinal System

Physiology system

Protection and Survival -Skin -Immune System

-Skeletal -Muscular System -Reproduction System

Physiology System

· A closed system of the heart and blood vessels· The heart pumps blood

· Blood vessels allow blood to circulate to all parts of the body

· The function of the cardiovascular system is to deliver oxygen and nutrients and to remove carbon dioxide and other waste products

Cardiovascular system

· Location· Thorax between the lungs

· Pointed apex directed toward left hip

· About the size of your fist

The Heart

Heart

· Pericardium – a double serous membrane· Visceral pericardium

· Next to heart

· Parietal pericardium

· Outside layer

· Serous fluid fills the space between the layers of pericardium

Heart covering

· Three layers· Epicardium

· Outside layer· This layer is the parietal pericardium· Connective tissue layer

· Myocardium· Middle layer· Mostly cardiac muscle

· Endocardium· Inner layer· Endothelium

Heart wall

External Heart Anatomy

Four chambers· Right and left side act as separate pumps

· Atria· Receiving chambers

· Right atrium· Left atrium

· Ventricles· Discharging chambers

· Right ventricle· Left ventricle

The heart Chambers

Blood Circulation

· Allow blood to flow in only one direction· Four valves

· Atrioventricular valves – between atria and ventricles· Bicuspid valve (left)· Tricuspid valve (right)

· Semilunar valves between ventricle and artery· Pulmonary semilunar valve· Aortic semilunar valve

Heart:valves

Operation of Heart valve

· Aorta· Leaves left ventricle

· Pulmonary arteries· Leave right ventricle

· Vena cava· Enters right atrium

· Pulmonary veins (four)· Enter left atrium

Heart associate great vessel

· Intrinsic conduction system (nodal system)

· Heart muscle cells contract, without nerve impulses, in a regular, continuous way

Heart electrical/conduction system

· Special tissue sets the pace

· Sinoatrial node

· Pacemaker

· Atrioventricular node

· Atrioventricular bundle

· Bundle branches

· Purkinje fibers

· Contraction is initiated by the sinoatrial node

· Sequential stimulation occurs at other autorhythmic cells

Heart contraction

Cardiac cycle

· Atria contract simultaneously

· Atria relax, then ventricles contract

· Systole = contraction

· Diastole = relaxation

· Cardiac cycle – events of one complete heart beat

· Mid-to-late diastole – blood flows into ventricles

· Ventricular systole – blood pressure builds before ventricle contracts, pushing out blood

· Early diastole – atria finish re-filling, ventricular pressure is low

· Cardiac output (CO)

· Amount of blood pumped by each side of the heart in one minute

· CO = (heart rate [HR]) x (stroke volume [SV])

· Stroke volume

· Volume of blood pumped by each ventricle in one contraction

Cardiac output

Cardiac output regulation

Blood Pressure

Electrocardiogram

Stress Test

Angiography

Measuring cardiac function

Measure of fluid pressure within system Systolic Pressure: Pressure generated by contraction Diastolic Pressure: Pressure achieved between

contractions. SBP reflects the amount of work the heart is performing

DBP indicates the amount of peripheral resistance encountered

Arterial pressure increases with age, DBP more than SBP

With aging, major blood vessels increase in rigidity

Blood Pressure

Electrocardiogram Measure of the electrical activity of the heart

ECG block diagram

Stress Test ECG during Exercise

Cardiac catheterization Inject dye into heart X-ray to examine blockages

Angiography

Bipolar lead (Three leads):-

lead I = left arm minus right arm (LA–RA)

lead II = left leg minus right arm (LL–RA)

lead III = left leg minus left arm (LL–LA)

Lead ll =Lead l + Lead lll (called Einthoven triangle)

ECG acquisition

Unipolar leads These have an exploring electrode placed on a chosen site linked with an indifferent electrode with a very small potential.

Unipolar Chest leads V1, the fourth intercostals space just to the right of the sternum V2, the fourth intercostals space just to the left of the sternum V3, midway between V2 and V4 V4, the fifth intercostals space in the midclavicular line V5, the left anterior axillaries line at the same horizontal level as

V4 V6, the left midaxillary line at the same horizontal level as V4.