Coronary Artery Disease Flashcards
Outer Layer
Adventitia
Basic support structure
Middle Layer
Media
Multiple layers of smooth muscle cells
Makes adjustments to luminal diameter
Inner Layer
Intima
Intima
endothelial layer, basement membrane, smooth muscle cells
What is the primary driving force moving blood into myocardial tissue?
diastolic BP
What plays a role in determining volume of blood passed along to tissue?
vasomotor tone
Left ventricular end-diastolic pressure
the pressure within the ventricle at end diastole
Atherosis
Fatty streak that consists of lipid-laden macrophages and smooth muscle cells
Sclerosis
Responsible for reduction of blood vessel compliance
Organization of “fibrous cap” of thrombi over advanced plaques that have developed on endothelial lining
Lesions of Atherosclerosis
Fatty Streak
Raised Fibrous Plaque
Complicated Plaque
Vasospasm
Hyperplasia of intimal smooth muscle cells is hallmark of advanced atherosclerosis creating a coronary artery that is prone to spasm
Prinzmetal angina
variant angina associated with ST-segment elevation, at rest, and not associated with any preceding increase in myocardial oxygen demand
Modifiable risk factors:
Cigarette/tobacco smoking
High blood pressure (over 140/90)
High blood cholesterol levels – best predictor is ratio of total cholesterol to HDL
Physical inactivity
Nonmodifiable risk factors:
Heredity
Male sex
Increased age
Classic stable angina:
tightness, pressure, indigestion anywhere above the waist that develops with exertional activity and relieved with NTG
Unstable angina:
chest discomfort that is accelerating in frequency or severity and may occur while at rest but does not result in myocardial necrosis
-acute MI
Pericarditis:
pain at rest, may worsen with activity,but is not relieved with rest or NTG, responds to anti inflammatory meds.
Factors that Contribute to Unstable Angina
Circadian variations in catecholamine levels
Increases in plasma viscosity
Increases in platelet activation
Pathological changes in atherosclerotic plaques
Printzmetal’s variant angina (vasospasm)
supply ischemia
Chronic stable angina (fixed stenosis)
demand ischemia
Unstable angina (thrombus)
supply ischemia
STEMI
develops a Q wave on ECG in subsequent 24 to 48 hrs (transmural infaction)
Non-STEMI
does not develop a Q wave on ECG (referred to nontransmural or subendocardial region infarction)
Right coronary artery infarction
increased risk of AV block and/or arrhythmia
50% have right ventricular infarct
Left main artery infarction:
pump dysfunction or failure
Left anterior descending (LAD) infarction
pump dysfunction or failure
Circumflex infarction
non specific
Abnormal contraction patterns
Dyssynchrony
Hypokinesis
Akinesis
Dyskinesis
Dyssynchrony
uncoordinated contraction with adjacent segments
Hypokinesis
reduction in the strength of contraction
Akinesis
no contraction
Dyskinesis
abnormal movement during contraction
Factors that affect remodeling
Size of infarct
Ventricular load
increased pressure or increased volume will increase load
Patency of the artery that was infarcted
Hypertensive Heart Disease
Produces a pressure overload on left ventricle
Diastolic dysfunction with impairment of LV relaxation develops early
Systolic Dysfunction:
an impairment in ventricular contraction, resulting in decrease in stroke volume and decrease in ejection fraction (less than 40%). An increase in end systolic volume will also occur. Now called heart failure with reduced ejection fraction or HFREF.
Prehypertension Systolic
120-139
Prehypertension Diastolic
80-89
Stage 1 hypertension systolic
140-159
Stage 1 hypertension diastolic
90-99
Stage 2 hypertension systolic
greater than 159
Stage 2 hypertension diastolic
greater than 99
Dystolic Dysfunction:
Changes in ventricular diastolic properties that lead to an impairment in ventricular filling and an impairment in ventricular relaxation.
Medical clearance needed:
SBP >180 mmHg & DBP >110 mmHg) pt’s must have medial clearance & prescribed medication for HTN
Exercise testing should be terminated if
SBP >250mmHg or DBP >115 mmHg
Orthostatic hypotension
SBP dop of >20mmHg or DBP drop >10mmHg
Refer to physician if resting BP is
(SBP >200 mm Hg or DBP >100 mm Hg)
Exercise recommendations for PAD:
short intervals (1-5 mins) with frequent rest breaks (gradually increase)
walking
longer warm up times in colder environments
sensory exam
footwear and foot hygiene
