Ch 13 bb - Cardiovascular Disease

cardiovascular system

• heart and blood vessels

heart disease

• conditions that affect heart structure and function

coronary artery disease

• also called ischemic heart disease

• major cause of death in US

• narrowing or blockage of coronary arteries

• result: arteries f the heart can’t deliver enough oxygen-rich blood to the heart

• lack of enough blood cause ischemia (conditions where heart doesn’t get the oxygen and nutrients it needs)

• ischemia can cause angina (discomfort or pain in chest) and increased risk of heart attack

angina

• most common symptom of coronary artery disease; pain or discomfort when your heart doesn’t get enough blood

• stable angina: happens during exercise or under stress

• unstable angina: happens at rest; considered a medical emergency

what causes narrowing of arteries?

• atherosclerosis

• vasospasms

• plaque buildup and vasospasms may occur individually, or may co-occur in the same artery

atherosclerosis

• buildup of plaque (fats, cholesterol and other substances) in & on the walls of large and medium-sized arteries, which leads to narrowing of the inside of the arteries

vasospams

• arteries can undergo spasms (tighterning) that temporarily narrow the arteries and block blood flow to the heart

types of coronary artery disease

• obstructive coronary artery disease

• non-obstructive coronary artery disease

obstructive coronary artery disease

• plaque builds up in the large arteries, causing them to narrow gradually & reducing the supply of oxygen-rich blood to the heart

• over 50% of heart’s arteries are blocked

• blood flow may eventually be completely blocked in one or more of the three large coronary arteries

non-obstructive coronary artery disease

• arteries are less than 50% blocked

plaque

• substance made of fat, cholesterol, calcium & other substances that builds up and hardens in arteries

coronary microvascular disease

• affects the heart’s smallest arteries

• can happen either alone or with obstructive or non-obstructive coronary artery disease or other heart heart disease

• most often occurs when molecular changes in the tiny blood vessels of the heart prevent normal blood flow through the small arteries

(congestive) heart failure

• heart can’t pump enough blood to meet the body’s needs

• doesn’t mean the heart has stopped pumping

• fluid buildup in lungs, liver, GI tract, arms, egs

• only curable with a heart transplant

• both adults and children can have it

leading causes of heart failure

• high blood pressure

• diabetes

• coronary artery disease can weaken the heart muscle, leading to heart failure

heart attack

• also called a myocardial infarction

• happens when a part of the heart muscle doesn’t receive enough blood; e.g., due to blood clot

• coronary artery disease is the major cause of heart attacks

• permanent damage to heart muscle

• ~750,000 americans have a heart attack every year

• 1 in 5 heart attacks occurs without the person realizing it

• fast medical attention reduces heart damage

cardiac arrest

• heart stops beating

• causes:

  • coronary artery diseases

  • cardiomyopathy

  • valvular heart disease

  • arrythmias

• without treatment, death occurs within minutes after cardiac arrest

• heart attack can trigger ventricular fibrillation and sudden cardiac arrest

cardiomyopathy

• heart muscle thickens, stiffens, or otherwise becomes abnormal, can lead to irregular heart beat

valvular heart disease

• damage or disease affecting any heart valve

arrythmias

• electrical malfunction in heart that causes irregular heartbeat; heart can’t pump blood properly

• ventricular fibrillation

ventricular fibrillation

• type of arrythmia affecting heart ventricles

• ventricles of heart (pumping chambers) don’t pump effectively

• cuts off blood supply to vital organs

• can be deadly within seconds

cardimyopathy

• heart becomes enlarged, stiff, or otherwise abnormal; can weaken heart

• causes include family history, hypertension, prior heart attacks, viral or bacterial infections

congenital heart defects

• most common type of major birth defect

• examples: abnormal heart valves or holes in the walls of the heart

non-modifiable heart disease risk factors

• age

• sex

• family history

• genetic predisposition

modifiable heart disease risk factors

• hypertension

• smoking & nicotine use

• poor diet

• alcohol intake

• physical inactivity

• dyslipidemias

• obesity

• diabetes

• metabolic syndrome

• stress

lipids and dyslipidemia (hyperlipidemia)

• high triglycerides + low HDL + high LDL → increased risk f cardiovascular disease

cholesterol

• a waxy substance your body needs, too much LDL can cause problems

triglycerides

• type of fat found in blood

stent for treating narrowed coronary artery

• long, thin tube (catheter) is inserted into narrowed section of artery

• a wire with a deflated balloon is passed through the catheter to the narrowed section

• balloon is inflated, compressing the deposits against the artery walls

• the stent (a metal mesh) is often left in to help keep artery open, may slowly release medication

treatment: coronary artery bypass surgery

• requires open heart surgery

• normally done if there are multiple narrowed coronary arteries

• graft to bypass blocked artery is created with a vessel from another part of the patient’s body

stroke

• blood supply to part of brain is reduced or interrupted

• brain tissue is deprived of oxygen and nutrients → cell death within minutes

• medical emergency - quick treatment can help reduce brain damage/disability

types of strokes

• ischemic stroke

• hemorrhagic stroke

• TIA (transient ischemic attack)

ischemic stroke

• occurs due to obstruction in blood vessel supplying blood to brain; accounts for 87% of all stroke cases

hemorrhagic stroke

• occurs when a weakened blood vessel ruptures; most common cause is uncontrolled hypertension

TIA (transient ischemic attack)

• caused by a temporary clot; often called a “mini-stroke”

• produces stroke-like symptoms but often has no lasting effects; medical treatment for TIAs can reduce the risk of a major stroke

risk factors for stroke

• smoking

• diabetes

• high LDL cholesterol

• carotid artery or other artery disease(carotid arteries supply most of the blood to brain)

• physical inactivity

• obesity

• personal or family history of stroke or TIA

• atrial fibrillation (upper chambers of heart quiver, don’t beat properly, can cause blood to pool & clot)

• sickle cell anemia

• excessive alcohol intake

• sleep apnea

• increasing age

• female gender (higher lifetime risk)

• race: hispanics and african americans have higher stroke risk