Cardiovascular Flashcards
is a condition that occurs when perfusion of the myocardium is compromised due to some imbalance between myocardial oxygen supply and/or demand
Ischemia
is regulated by the patency or size of the lumen of the coronary vessel, the ability of the ventricular wall to compress and the amount of time the ventricle spends in diastole
Oxygen supply
is dependent upon myocardial contractility, HR, and amount of ventricular stress
Demand
an abrupt or acute reduction in blood flow to the myocardium caused by thrombus, coronary vasospasm or platelet aggregation.
Supply ischemia
an increase in need for oxygen and nutrients due to exercise or stress
Demand ischemia
3 common causes of ischemia?
- blockage of coronary artery (thrombus)
- spasm of coronary artery
- coronary artery obstruction (formation of plaque)
It only takes ___ mins to progress to necrosis if the flow to the myocardium is not restored
20 mins
is a continuum that begins with plaque rupture within a coronary artery and results in infarction of myocardial tissue if perfusion is not restored in good time.
acute coronary syndrome
3 phases of acute coronary syndrome
- unstable angina
- NSTEMI
- STEMI
Formation of fatty fibrous lesion with a lipid core and fibrous cap
stable angina
Rupture of fibrous cap allows leaking of lipids and platelet aggregation
unstable angina
Clot formation
NSTEMI
Thrombus causes occlusion of vessel
STEMI
The T wave represents
ventricular repolarization
is often seen on an ECG as ST segment depression and T wave inversion during the period of pain.
unstable angina
necrosis of myocardial tissue occurs, but because the full thickness of the ventricle is not involved, electrical activity is not disrupted and there are no obvious changes on the ECG.
non-STEMI
is an enzyme found in the heart, brain, and skeletal muscle and is released when these cells are damaged.
Creatinine Kinase (CK)
CK-MM
skeletal muscle
CK-BB
brain tissue
CK-MB
myocardial tissue
- a protein found in skeletal and cardiac muscle
- increases earlier, more quickly, and stays elevated longer than CK
Troponin
arterial occlusion is complete, resulting in necrosis of the full thickness of the ventricle, which alters electrical conduction.
STEMI
seen as ST elevation on the ECG and cardiac biomarkers are elevated
STEMI
cell death and necrosis has occurred; seen as pathological Q waves on the ECG; cells replaced with scar tissue.
zone of infarct
injured but potentially viable tissue, surrounding the area of infarct; seen as ST segment elevation on the ECG
zone of injury
outer region of the infarcted area; cells are still viable; manifests as T wave inversion on the ECG.
zone of ischemia
is depicted by the flipped or inverted T wave
ischemia
depicted by the elevated ST segment
injury
depicted by a pathological Q wave (deep or wide)
infarct
are often caused by movement to anaerobic metabolism in the presence of ischemia without manufacture of enough ATP
Dysrhythmias
decreases afterload through vasodilation
morphine
vasodilates vascular smooth muscle, decreases afterload and myocardial oxygen demand and improves coronary and artery blood flow.
nitroglycerin
prevents platelet aggregation; should be chewed
ASA
decrease workload of the heart by decreasing contractility and heart rate
beta-blockers
prevents activation of the glycoprotein IIIb/IIIa complex required for platelet aggregation
Adenosine Diphosphate Receptor Antagonist (Clopidogrel)
accelerates action of anti-thrombin, which inactivates thrombin to prevent formation of thrombus
Anticoagulant (Heparin)
fibrinolysis is achieved with tenecteplase (TNK) to re-establish artery patency.
Reperfusion therapy
A balloon tipped catheter is used to open occluded arteries in the catherization lab; a stent may be inserted to keep the artery open
PCI- percutaneous coroniary intervention
A surgical technique where the patient’s own blood vessels are harvested from a distant site, and used to bypass an occluded artery.
CABG- coronary artery bypass grafting
Decreases thrombus formation by making platelets less “sticky” so that risk of clot formation is decreased.
Glycoprotein IIIb/IIIa inhibitors
Results in relaxed vessels and decreased LV workload
Prevents conversion of angiotensin I to angiotensin II
ACE-I
Prevents angiotensin from attaching to receptors, which inhibits vasoconstriction and ultimately decreases LV workload
ARB (angiotensin receptor blocker)
Inhibit HMG-CoA Reductase, the enzyme needed for cholesterol synthesis, reducing LDL levels
Statins
Due to fluid shifting from capillaries, the individual develops congestion of peripheral tissues, including the liver, GI tract and distant periphery such as the ankles
right sided HF
Pulmonary congestion occurs, as fluid leaks into pulmonary tissues
left sided HF
what is a normal ejection fraction?
50-75%
the amount of volume in the ventricle at the end of diastole
preload
the amount of resistance the ventricle is up against as it tries to contract
afterload
the ability of the muscle to stretch and contract, like an elastic
contractility
refers to the patient for whom normal daily falls to produce symptoms
class I
refers to those whose normal daily activities initiates symptoms but the patient controls them with rest
class II
is reserved for those in whom minimal activity produces symptoms, but they remain symptom free at rest
class III
is attributed to those for whom any activity precipitates symptoms
class IV
____ balances arterial and venous vasodilation reducing BP, permitting the LV to eject more efficiently, raising the CO and decreasing serum levels of NE and aldosterone, and blunting activation of the RAA system
Nesiritide (a synthetic BNP)
is a unique form of pacemaking that helps to re-establish normal coordinated contractions between the atria and ventricles of the heart
Cardiac resynchronization therapy (CRT)
are medications that improve contractility, decrease afterload
inotropes
reduce volume and thus, pressures by inducing sodium and water excretion
diuretics
Increase contractility, but also increase oxygen consumption and should be used with caution
beta adrenergic agonists
also improves contractility through inotrope effects but also acts as a negative chronotrope, reducing heart rate and thus myocardial workload
cardiac glycosides (ex. Digoxin)
improve contractility, vasodilate, increase CO and reduce BP, given IV and in the short term
phosphodiesterase inhibitors
Prevents angiotensin II activity as well as that of aldosterone; improves hemodynamic function; decreases afterload and MV02
ACE-I
increase venous capacity, reducing afterload
vasodilators
have negative chronotropic and inotropic activity, decreasing the overall workload of the heart
Beta blockers
