the Heart

Heart wall layers

Endocardium- lines heart interior; provides smooth surface for easy blood flow through heart-which covers flaps of heart valve

Myocardium-thickest layer of the heart wall; pumps blood through vessels

Epicardium-forms thin outermost layer of heart wall

Pericardium

Sac that encloses heart; sacs most outermost and heaviest layer, fibrous and is a connective tissue membrane

Myocardium

Uses intercalated disks that permit electric impulses, sends signals to contract through heart muscle to have affective pumping

Divisions of heart

Acts as a double pump; right side pumps blood LOW in oxygen to lungs-pulmonary circuit

Left side pumps HIGHLY oxygenated blood into the remainder of body-systemic circuit

Four chambers of heart

Right atrium- receives blood from other body parts, superior vena cava- brings blood from head chest and arms, inferior delivers blood from trunk and legs

Right ventricle- receives blood from right atrium and pumps it to the lungs which then goes through the pulmonary trunk

Left atrium- receives oxygenated rich blood as it returns from lungs then to pulmonary veins

Left ventricle- pumps oxygenated blood to all parts of the body, including lung tissue

Four valves

right (av) node- aka tricuspid valve, it has three cusps that open and close, when open it allows blood to flow freely through right atrium into right ventricle

Left (av) node- aka mitral valve, 2 heavy cusps that permit blood to flow freely from left atrium to left ventricle

Pulmonary valve- when right ventricle relaxes, pressure in chamber drops, then closes to prevent blood from returning to ventricle. Located between right ventricle and pulmonary trunk

Aortic valve- left ventricle relaxes, back pressure closes aortic valve and prevents back flow of blood from aorta to ventricle

Hearts conduction system

Potential spread rapidly through conducting cells in a specific pattern;

Sa node-sends signal

Internodal pathways-give signal

Av node- delays signal

Right and left bundle branch-signal ventrical septum

Perjunke Fibers-carry signal through ventricle, stimulating contraction

Cardiac output

Cardiac output; volume of blood pumped by each ventricle in one minute

CO=HRxSV

Heart sounds

Normal- Lub Dup

Abnormal-organic murmur

Functional murmur- normal sounds that are heart when the heart is working

Heart studies

Examples include; echocardiogram, electrocardiography, coronary angiography, catheterization/fleuroscope, stethoscope

Heart inflammation

Examples- endocarditis, myocarditis, pericarditis

Valve disorders

Valvular stenosis- failure to open completely l or have narrowed openings

Valvular insufficiencies- failure to close properly leading to back flow

Rheumatic heart disease- originates from rheumatic fever

Coronary artery disease

Caused by; degenerative changes

Cant change- heredity, age, gender, body type

Can change- exercise, smoking habits, weight

Heart failure

Hearts inability to pump efficiently

Can occur from myocardial infarction, hypertension or valvular deficiencies

Heart disease treatment

-Lifestyle changes

-medications such as statins, anticoagulants, digitalis, beta blockers, calcium channel blockers etc