PBM Lecture Exam 2 Flashcards
Most coronary blood flow during what stage of cardiac cycle?
diastole
Compare skeletal and cardiac m
O2 debt
anaerobic metabolic
Skeletal
- -O2 debt repaid during rest
- -anaerobic provides 40% of energy during exercise
Cardiac
- -O2 debt rarely incurred
- -anaerobic only used during extreme hypoxia
Atherosclerosis
complex arterial disease in which cholesterol deposition, EC matrix, and thrombus formation play major roles
Atherothrombosis involves…
heart (coronary aa)
brain (carotid, vert, cerebral aa)
aorta
periph aa
if there is a significant underlying coronary epicardial stenosis present,
blood flow at rest is maintained by…
compensatory dilation of coronary bed beyond the stenosis
if there is a significant underlying coronary epicardial stenosis present,
diminished coronary reserve results in
inability to meet O2 requirements as myocardial demand inc –> creates supply/demand mismatch
Stable angina vs unstable angina
stable: vague chest/arm discomfort that is reproducibly associated w/ physical exertion or stress and is relieved w/in 5-10 min by rest of sublingual nitroglycerin
unstable: freq angina, even at rest/minimal exertion – lasts more than 20 min, severe PAIN, occur w/ crescendo pattern (more severe, prolonged, frequent)
how much of coronary a must be blocked for there to be a problem?
70%
Describe physiology of plaque
foam cells
cholesterol builds up in matrix of aa (thin, fibrous caps and lipid rich cores)–> plaque
plaque inflamed and pops –> bleeds
thrombus forms (platelet aggregtion, fibrin deposition, vasoconstriction)–> obstructs a –> MI
another plaque forms over this –> further narrowing
Angina occurs when myocardial work load (O2 demand) ____ the capacity of myocardial blood supply (O2 delivery)
when O2 demand exceeds O2 delivery
Clinical presentation of angina
symptoms provoked by: 4E's -exertion -eating (heavy meals) -emotional distress -environment symptoms reproducible and present for prolonged period of time
CAD symptoms experienced by women
back right side weak sweats nausea atypical pain
Risk factors for CAD
obesity BP carotid bruit dec periph pulses S4 sounds may have normal ECG
Areas where angina pain radiates
neck jaw upper abdomen shoulders arms
Diagnose CAD using
cardiac risk factors ECG Chest X ray stress test angiography guided therapy
