chapter 13 - CAD Flashcards
what is the most common cause of death in adults in the US
CAD
what is the prognosis of CAD dependent on
number of coronary vessels obstructed by plaque and the severity of obstruction/occlusion
is left ventricular dysfunction an important factor in predicting survival outcomes in CAD
yes
evidence of _________ will usually predict reduced survival in the absence of medical or surgical intervention
ongoing ischemia
what does risk factor analysis include (CAD)
age and gender, genetic predisposition such as familial dyslipidemias, lipids, obesity, HTN, DM, homocysteine and CRP
the coronary arteries are major blood vessels that emerge from the _______ to supply the heart muscle with ______ and ______
aortic root, oxygen and nutrients
what are the 3 layers of the coronary arterial wall
intima, medial, adventitia
what is the name of the open space through which blood flows in the coronary arteries
lumen
Myocardial ischemia occurs when the ________ cannot meet the ________ in a region of the ventricle
myocardial oxygen supply…. myocardial oxygen demand
myocardial infarction refers to the _________ that occurs following prolonged ischemia
irreversible myocardial cell injury and death
myocardial oxygen demand is controlled by:
heart rate, contractility of the myocardium, LV wall tension
what classification system is often use to classify the severity of angina
Canadian Cardiovascular Society
what anginal symptoms are presumptive evidence of typical angina with 90% likelihood of angiographically significant disease
CP with exercise, effort and emotion, and relief with rest or NTG
coronary revascularation offers high probability for relief or improvement of angina symptoms over what time period
5-10 yrs
what is prinzmetal angina (variant angina pectoris) and what can it be associated with
CP at rest, ST-segment elevation on ECG, associated with acute MI, severe cardiac arrhythmias, sudden death
what is cardiac syndrome C
angina or angina-like chest pain with a normal coronary angiogram. no EKG changes.
what is silent myocardial ischemia
episodes of asymptomatic ischemia, with objective evidence of coronary insufficiency
most people with unstable angina have ____
multi vessel CAD
approximately 1/4 of all deaths are due to ____
MI
more than 50% of deaths from MI occur within ______ of the event and are attributable to ______
one hour, arrhythmias, often ventricular fibrillation
what labs are done and repeated after 8-24 hrs if suspected MI
CPK, MB fraction, myoglobin and cardiac-specific troponin (T and I)
what are the most specific and sensitive biomarkers for MI
cardiac troponins
more than 20 hrs after MI the ______ may return to normal and _____ can be elevated instead
CPK, LDH
what is the major cause of death for people with CAD and how is it defined
sudden cardiac death, death from cardiac disease within one. hour of the onset of symptoms in someone who was not expected to die
most sudden cardiac deaths are due to _____
arrhythmias occurring in presence of chronic coronary or structural heart disease. less often - cardiomyopathy, inherited depolarization abnormalities.
what is a stress test terminated by
reading maximal heart rate, marked EKG changes, sig BP changes, or reproduction of typical chest pain
what is indication of myocardial ischemia
ST-segment depression, radionuclide imaging defects or wall motion abnormalities on echo
what are possible explanations for false-positive tests (for MI)
ventricular hypertrophy, MVP, conduction abnormalities
possible explanations for false negative tests for MI include
failure to achieve adequate HR, baseline EKG changes that limit the interpretation of exercise tracings, meds that suppress the development of ischemia
how is PET useful to test for CAD
identifies how much of the heart has been damaged by infarction and how much is still viable
what degree of stenosis is usually considered significant (for CAD)
50-70% or greater
proximal lesion implies the stenosis is ____
close to the origin of the artery
distal lesions are those that occur _______
near the terminal portions of the imaged artery
the prognosis of CAD will be directly related to the amount of damage that could occur should the lesion undergo sudden and total occlusion, termed the ______
myocardium at risk
in CAD, survival is best in what scenario
single-vessel disease where obstruction is limited to one artery
in CAD, intermediate survival rates in what type of disease
two vessel or doubele vessel disease
worst prognosis for CAD in what situation
triple vessel disease
lesions in what artery are most significant (CAD)
left main
do distal lesions or proximal lesions have greater risk
proximal
are LAD lesions associated with large amount of myocardium at risk? why or why not?
yes, because this artery provides blood flow to the functionally important anterior, septal, and apical walls of the LV.
when myocardial oxygen supply cannot meet demand it is:
- angina
- hypoxia
- ischeima
- infarction
3, ischemia
all of the following findings on a post-myocardial infarction exercise test can help identify individuals at high risk for recurrent event EXCEPT:
- angina symptoms
- low exercise capacity
- rising systolic BP
- ischemic ST-segment depression at low workloads
- rising systolic BP
which of the following statements regarding adenosine stress testing is/are accurate?
A. its results are typically less accurate than the results of standard exercise testing
B. it is used for individuals who are unable to undergo standard exercise testing
C. it requires concurrent radionuclide or echocardiographic imaging
B and C
