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Heart Diagram
Label
FUNCTION
TO PRESSURIZE THE BLOOD
AND CAUSE IT TO FLOW THROUGH THE
VESSELS.
LAYERS OF THE HEART
PERICARDIUM- A DOUBLE LAYERED SAC THAT COVERS
THE HEART.
INSIDE THE SAC IS SEROUS FLUID WHICH PREVENTS
FRICTION.
• MYOCARDIUM- THE HEART MUSCLE ITSELF. (THE
THICKEST LAYER).
• ENDOCARDIUM- LINES THE HEART.
WHAT IS PERICARDITIS?
• AN INFLAMMATION OF THE PERICARDIUM
• USUALLY INFLAMMATORY OR VIRAL
• NOT USUALLY BACTERIAL
• DECREASED PRODUCTION OF SEROUS FLUID
• CAUSES A RUSTLING SOUND, A FRICTION RUB
PROBLEM
IF THE HEART CONTINUES TO RUB, THIS CAN
EXERT EXCESS PRESSURE & CAUSE HEART
FAILURE.
WHAT IS ENDOCARDITIS?
• INFLAMMATION OF THE ENDOCARDIUM
• USUALLY THE ENDOCARDIUM COVERING THE
HEART VALVES
• A BACTERIAL INFECTION
ANATOMY OF THE HEART
4 CHAMBERS:
• 2 SUPERIOR, THIN-WALLED ATRIA
• 2 INFERIOR, THICK-WALLED VENTRICLES
HEART VALVES
PREVENT THE BACKFLOW OF BLOOD
(Tricuspid valve, pulmonary valve, bicuspid
valve, Aortic valve)
animation of heart valves
find the heart with a virtual
stethescope
http://www.smm.org/heart/heart/stet
h.htm
VALVE PROBLEMS
1. INCOMPETENT VALVE
THE VALVE OPENS BUT DOES NOT CLOSE
COMPLETELY. BACKWARD LEAKAGE OCCURS.
THE HEART WORKS HARDER & THIS CAN LEAD
TO HEART FAILURE.
2. VALVULAR STENOSIS
•
A STIFF VALVE
•
DOES NOT OPEN ALL THE WAY
•
MOST OFTEN DUE TO A SERIOUS BACTERIAL
INFECTION
•
BACTERIA CAUSE FORMATION OF SCAR
TISSUE ON THE VALVE.
NORMAL AORTIC VALVE
AORTIC
STENOSIS WITH
CALCIFICATION
Tx
VALVE REPLACEMENT: EITHER
MECHANICAL
MECHANICAL
MITRAL VALVE
REPLACEMENT
PATHWAY OF BLOOD THROUGH THE BODY
(valves not included)
SUPERIOR & INFERIOR VENA CAVA & CORONARY VEINS
RIGHT ATRIUM
RIGHT VENTRICLE
PULMONARY ARTERY
LUNGS
Pulmonary veins
LEFT ATRIUM
LEFT VENTRICLE
AORTA
ARTERIOLES
Capillary (TISSUES) venule to veins
Please follow the path of circulation through
the heart in the link below.
http://www.smm.org/heart/heart/pumping.htm
BLOOD SUPPLY TO THE
MYOCARDIUM
THE HEART IS NOT NOURISHED BY THE BLOOD
THAT PASSES THROUGH IT.
CORONARY ARTERIES SUPPLY O2 RICH BLOOD
B. MYOCARDIAL INFARCTION (MI)
• A HEART ATTACK
• PART OF THE MYOCARDIUM DIES
• DUE TO PROLONGED LACK OF BLOOD & O2
• SCAR TISSUE FORMS
• SCAR TISSUE CANNOT CONTRACT
• HEART BECOMES STIFF
• WORST MI?
• THE LEFT VENTRICLE
FACTS
1 MILLION DIE FROM HEART DISEASE IN
THE U.S. EACH YEAR
#1 CAUSE OF DEATH IN THE U.S.
MOST IMPORTANT Sx?
CHEST DISCOMFORT THAT LASTS FOR MORE THAN A
FEW MINUTES
Tx
1. CLOT BUSTERS
2. ANGIOPLASTY
3. BY-PASS
CLOT BUSTERS
• TPA & STREPTOKINASE
• MUST BE GIVEN WITHIN THE FIRST 90 MINUTES
• WHY?
• TISSUE DIES BY THIS TIME
• WHEN SHOULD YOU NOT GIVE A CLOT BUSTER?
• WHEN THERE IS A CHANCE OF SURGERY
ANGIOPLASTY
• ALSO CALLED BALLOON SURGERY
• AN INFLATED BALOON IS PRESSED AGAINST
THE WALL OF THE ARTERY TO COMPRESS THE
OBSTRUCTION (PLAQUE)
• ABOUT 2/3 FAIL WITHIN ONE YEAR
OCCLUDED ARTERY
BLOOD
BLOOD
VESSEL
PLAQUE
BALLOON TO BE INFLATED
HEART CONDITIONS
A. ANGINA PECTORIS- CHEST PAIN DUE TO LACK OF O2
TO THE MYOCARDIUM
1.
2 CAUSES:
SPASM OF THE CORONARY ARTERIES.
COLD CAN TRIGGER.
•
Tx: NITROGLYCERINE
2. TOO MUCH PHYSICAL DEMAND
•
Tx: SLOW DOWN
BY-PASS SURGERY
• IS THE MOST DANGEROUS
• CHEST WALL IS CRACKED OPEN
• A VEIN IS USED TO REPLACE THE BLOCKED AREA OF
THE ARTERY
• USUALLY A VEIN FROM THE LEG
•
• ONLY GOOD FOR ABOUT 10 YEARS
Prevention Therapy
Recommendations: A baby aspirin each day
Who should avoid taking aspirin?
1. anyone with an allergy to aspirin
2. anyone with asthma
3. anyone with stomach ulcers
4. anyone with bleeding disorders
5. anyone with reduced liver or kidney function
6. anyone with uncontrolled high blood pressure