Exam 2 Cardiac Flashcards
what is acute coronary syndrome?
unstable angina
NSTEMI
STEMI
what is the triad of I’s?
Ischemia
injury
infarction
what do the triad of I’s represent?
all represent an O2 supply problem:
ischemia = reversible
injury = acute period of both ischemia and infarction
infarction = irreversible cell death
a clinical syndrome usually resulting from disrupted atherosclerotic plaque, which subsequently results in an imbalance between myocardial oxygen supply and demand.
unstable angina (U/A)
U/A and _______ ___________ are closely related in presentation.
Non-STEMI
what do U/A ECG show?
May show ST depression or may be normal
cardiac enzymes are normal
Ischemia is reversible
differs from unstable angina mostly due to severity of ischemia, causes enough myocardial damage to release detectable cardiac markers indicating myocardial injury [Troponin I (TnI), Troponin T (TnT), and/or creatinine kinase (CK-MB)]
Non-ST elevation Myocardial Infarction (Non-STEMI)
what ECG changes occur with a Non-STEMI?
changes my occur, no sustained ST segment elevation.
can limit the area of infarction through medical and nursing interventions.
a loss of cardiac myocytes as a result of prolonged ischemia due to a perfusion-dependent imbalance between supply and demand.
ST elevation myocardial infarction (STEMI)
does not cause immediate cell death but rather it occurs over a finite period of time. it can take at least 4-6 H for complete necrosis of myocardial cells.
myocardial ischemia
what is dependent upon the presence of collateral blood flow into the ischemic zone or coronary artery occlusion?
STEMI
What is important to know about the cardiac marker Troponin (T,I)?
very specific and more sensitive than CK, rises 4-8 H after injury, may remain elevated for up to 2 wks, can provide prognostic info, and may be elevated with renal dz, poly/dermatomyositis
What is important to know about the cardiac marker CK-MB Isoenzyme?
rises 4-6H after injury and peaks at 24H, remains elevated 36-48H, positive if CK/MB >5% of total CK and 2 times normal, elevation can be predictive of mortality, and false positives with exercise, trauma, muscle dz, DM, and PE
what are the cardiac risk factors that cannot be changes?
heredity
gender
age
what are the cardiac risk factors that can be changed or controlled?
smoking
HTN
hypercholesterolemia
obesity
physical inactivity
stress
DM
What is the most important diagnostic info?
the patient’s “story”
- current symptoms
-time of onset
-pain assessment
-past med history/meds
what are the typical S/S of MI?
chest discomfort:
-crushing, pressure, tightness
-sustained
-unrelieved or partially relieved by rest
-unrelieved or partially relieved by nitroglycerin
pain may radiate to other areas
what are the cardiac care goals?
-decrease amt. of myocardial necrosis
-preserve LV function
-prevent major adverse cardiac events
-treat life threatening complications
-start fibrinolytic therapy quick
-percutaneous coronary intervention (Cath lab) –> goal: door to balloon <90M)
NOTE: any recent bleeds (GI, cerebral, surgical) or ischemic stroke within 3 months are ABSOLUTE CONTRAINDICATIONS to these treatments!
Cardiac treatments?
Morphine
Oxygen
Nitroglycerin
Aspirin
What is the percutaneous coronary intervention?
- given an IV and anesthetic
- tube (cath) is inserted through groin or arm to reach hearts blood vessels
- dye is injected into blood vessels so they’ll appear on x-ray
- DR will look for blockages and any other issues
- Cath can also be used to clear blockages and make repairs
what is the nursing management after cardiac cath?
-cath site is observed for bleeding or hematoma
-temp and color of the affected extremity are elevated
-dysrhythmias are carefully assessed by observing the cardiac monitor
-bed rest must be maintained for 2-6H after the procedure
-observe for contrast agent induced renal failure
a blocked artery is bypassed within a vessel taken from another a vessel taken from another part of your body, this allows blood to flow freely to your heart again
coronary artery bypass grafting (CABG)
what do you need to understand with intra aortic balloon pump (IABP)?
the balloon pump operates on the principle of counter-pulsation
the pump inflates during diastole with increases coronary artery perfusion pressure, thus improving myocardial o2 supply
the pump deflates during systole which reduces afterload and augments cardiac output, thus reducing myocardial O2 supply.
what does a VAD pump do and what parts make up the VAD?
moves blood from the heart to the body, controller operates the pump and alerts the pt if the pump isn’t working correctly, 2 batteries pump power the pump and controller, and has a driveline connected to the heart.
