TOPIC 4 - cardiac system Flashcards
stages of atherosclerosis
- damage to endothelium
- fatty streak
- fibrous plaque
- complicated lesion
what causes endothelial injury
hypertension, tobacco use, hyperlipidemia, hyperhomocystemia, diabetes, infections, toxins
what happens in the fatty streak phase
lipids accumulates and migrates into smooth muscle cells
what happens in the fibrous plaque stage
collagen covers the fatty streak
vessel lumen is narrowed
blood flow is reduced
fissures can develop
what happens in the complicated lesion stages
plaque rupture
thrombus formation
further narrowing or total occlusion of vessel
factors contributing to the growth and extent of collateral circulation
inherited predisposition to develop new blood vessels
presence of chronic ischemia
non modifiable risk factors for CAD
age, gender, ethnicity, family hx, genetics
major modifiable risk factors
hypertension, tobacco use, elevated serum lipids, physical inactivity, obesity
contributing modifiable risk factors
DM, metabolic syndrome, psychologic states, substance abuse
clinical manifestations of CAD angina
chronic and progressive
greater O2 demand than O2 supply = myocardial ischemia
how much do arteries need to be blocked in order to be considered CAD
blocked 70% or more
50% or more for left main coronary artery
clinical manifestations of CAD causing chronic stable angina
intermittent chest pain that occurs over a long period with same pattern of onset, duration, and intensity of symptoms
few minutes in duration
ST depression and/or T wave inversion
controlled with drugs
pressure, heaviness, discomfort in chest (squeezing, heavy, tight, suffocating) not sharp or stabbing
dyspnea or fatigue
what provokes CAD
physical exertion, stress, or emotional upset
pain at rest is unusual
if angina is not treated, what can it turn into
MI
locations of where pain may be felt with angina
substernal, mid sternum, epigastric, intrascapular
can radiate to jaw, neck, shoulders, and arms
