THE HEART

THE HEART BEAT BEGINS AT 4 WEEKS ENUTERO FUNCTION TO PUMP BLOOD THROUGH THE BODY VIA THE ARTERIES, CAPILLARIES, AND VEINS DID YOU KNOW… THE HEART BEAT BEGINS AT 4 WEEKS ENUTERO

LOCATION IN THE THORACIC CAVITY IN THE MEDIASTINUM THE BASE IS AT THE TOP AND THE APEX IS AT THE BOTTOM JUST LEFT OF THE MIDLINE

CARDIAC MEMBRANES PARIETAL PERICARDIUM – LINES THE CAVITY VISCERAL PERICARDIUM – ON THE SURFACE OF THE HEART

LAYERS OF THE HEART EPICARDIUM – OUTERMOST LAYER OF THE HEART TISSUE MYOCARDIUM – MUSCLE THAT MAKES UP THE CHAMBERS OF THE HEART ENDOMETRIUM – INNER LAYER THAT IS SMOOTH TO PREVENT ABNORMAL BLOOD CLOTTING. IT MAKES UP THE VALVES.

CHAMBERS OF THE HEART UPPER CHAMBERS – LEFT AND RIGHT ATRIA SEPARATED BY THE INTERATRIAL SEPTUM LOWER CHAMBERS – LEFT AND RIGHT VENTRICLES SEPARATED BY THE INTERVENTRICULAR SEPTUM

FLOW OF BLOOD BLOOD ENTERS THE HEART FROM THE BODY VIA THE SUPERIOR AND INFERIOR VENA CAVA TRAVELS TO THE RIGHT ATRIUM PASSES THROUGH THE RIGHT AV VALVE (TRICUSPID VALVE) TRAVELS TO THE RIGHT VENTRICLE PASSES THROUGH THE PULMONARY SEMILUNAR VALVE TRAVELS THROUGH THE PULMONARY ARTERY TO THE LUNGS BLOOD HAS BEEN DEOXYGENATED AND NEEDS TO GO TO THE LUNGS TO PICK UP OXYGEN (BECOMES OXYGENATED BLOOD)

FLOW OF BLOOD BLOOD LEAVES LUNGS AND REENTERS HEART THROUGH 4 PULMONARY VEINS TRAVELS TO THE LEFT ATRIUM PASSES THROUGH THE LEFT AV VALVE (BICUSPID AKA MITRAL VALVE) TRAVELS TO THE LEFT VENTRICLE PASSES THROUGH THE AORTIC SEMILUNAR VALVE EXITS THE HEART THROUGH THE AORTA

FLOW OF BLOOD BLUE – DEOXYGENATED RED – OXYGENATED

PARTS OF THE AORTA ASCENDING AORTIC ARCH DESCENDING THORACIC ABDOMINAL

VALVES PREVENT THE BACKFLOW OF BLOOD

CARDIAC CYCLE PULSE – “LUB DUB” FIRST SOUND IS THE CONTRACTION OF THE VENTRICLES CLOSING THE AV VALVES (LUB) SECOND SOUND IS THE CLOSURE OF THE AORTIC AND PULMONARY SEMILUNAR VALVES (DUB) MURMUR – VALVE DOESN’T CLOSE PROPERLY

PULSE RATES NORMAL – RESTING PULSE IS 60 - 90 BRADYCARDIA – RESTING PULSE LESS THAN 60 TACHYCARDIA – RESTING PULSE GREATER THAN 100

BLOOD PRESSURE SYSTOLIC/DIASTOLIC SYSTOLE – CONTRACTION OF THE CHAMBERS OF THE HEART DIASTOLE – RELAXATION OF THE CHAMBER OF THE HEART HYPERTENSION – BP GREATER THAN 140/90

CARDIAC CONDUCTION CARDIAC MUSCLE HAS THE ABILITY TO CONTRACT SPONTANEOUSLY SA NODE – NATURAL PACEMAKER OF THE HEART LOCATED IN WALLS OF RIGHT ATRIUM IMPULSE TRAVELS TO THE AV NODE AND CONTINUES THROUGHOUT HEART

CORONARY ARTERIES SUPPLY BLOOD AND OXYGEN TO THE HEART FIRST BRANCHES OFF THE ASCENDING AORTA

REGULATION OF THE HEART MEDULLA OBLONGATA