11.3 Healthy Circulatory System

Plaque based diseases

• Over a lifetime we build up a deposit on the inside walls of our arteries– Made up of cholesterol

(LDL-C type), calcium and fat

• Too much of this can narrow the diameter of the arteries and lead to cardiovascular diseases

Plaque based diseases

• Atherosclerosis is the narrowing of the arteries due to plaque buildup

• If this occurs in the vessels that supply the heart it can lead to angina or a heart attack– Angina may also be caused by a blood clot and can

sometimes be treated using angioplasty– Heart attack, or myocardial infarction, occurs

when the blood supply has been stopped and some of the cells start to die

Plaque based diseases

• Arteriosclerosis is also known as ‘hardening of the arteries’– Arteries loose their ability to stretch due to plaque

build up– Increases blood pressure and the chance of blood

clots (hypertension)– Blocked coronary arteries may be treated with

bypass surgery

Plaque based diseases

• Sudden cardiac arrest can occur from many sources including coronary heart disease– If the heart stops beating or beats irregularly

(fibrillation) so blood is not being pumped through the body a person will die within minutes

– Defibrillators are used to restore the heart beat, also CPR can be used in emergencies

Cardiovascular disorders

• Arrhythmia occurs when the heart beats irregularly– One treatment is to install an artificial pacemaker

in the heart

Cardiovascular disorders

• Hypertension occurs when blood pressure exceeds 140/90 for an extended period of time– The higher pressure of blood flow/volume can

cause the heart muscles to expand– Over time they expand so much they can no longer

push blood through the body– Causes are sometimes genetic but in North

America are more likely due to excess weight, diet and lack of exercise

Cardiovascular disorders

• Heart failure occurs when the heart cannot pump enough blood or with enough force– Affects children and

adults– In some cases a heart

transplant is the only treatment

Cardiovascular disorders

• Aneurysm occurs when the walls of an artery bulge and may burst– Can be caused by injury,

disease or genetics– Often found in branches of

the aorta

Cardiovascular disorders

• Stroke occurs if a blood clot form in the brain and the tissues no longer get a supply of oxygen and nutrients– Can result in paralysis, loss of speech, memory

loss and sometime death

Cardiovascular disorders

• These are easier to prevent than to cure– Cholesterol – your body requires HDL-C but most

of us have diets high in LDL-C as found in beef, butter, ice cream, deep fried food, trans fats etc.• Learn to read labels and cook from scratch!

– Keep a healthy weight – Exercise regularly– Avoid smoking and second hand smoke– Regular yearly check ups to detect any problems