CV Labs & Diagnostics Flashcards
what is Troponin an indicator of?
most sensitive indicator of myocardial damage
what does troponin differentiate between?
cardiac vs non cardiac chest pain
how long after an MI does a troponin elevate?
2-3 hours
when does a troponin level return to baseline?
10-14 days
what is the lab draw schedule for troponin?
initial occurrence, 12 hours, then daily for 3-5 days
What is a CK-MB?
an enzyme found primarily in the heart muscle, helps to diagnose an acute MI
how long is a CK-MD elevated after an MI?
3 hours
when does a CK-MD peak?
24 hours after MI
between a troponin and a CK-MB which is more specific to cardiac damage?
troponin
What does CRP indicate?
inflammatory illness
NONSPECIFIC
when does a CRP peak?
18-72 hours
if a CRP fails to normalize what may it indicate?
ongoing damage to heart muscle
how is a CRP useful?
monitors acute inflammation
when is a CRP not elevated?
with angina
What is a ESR used for?
nonspecific indicator of acute OR chronic infection, inflammation, or tissue infarction
how is an ESR useful?
monitors for chronic inflammation
What is a BNP the main source in?
cardiac ventricle
what does BNP aid in?
distinguishing between cardiac vs. respiratory causes of dyspnea
when are concentrations higher in a Pro-BNP?
Left ventricular dysfunction
levels are approximately fourfold higher than BNP concentrations
what is the main lipid associated with CV disease?
cholesterol
what are the two sources of cholesterol?
endogenous and exogenous
what affects cholesterol?
malnutrition
what are two types of lipoprotiens?
HDL,LDL
are lipoproteins an accurate predictor of heart disease?
yes
what is HDL’s job?
to remove cholesterol
HDL is good cholesterol
What is LDL’s job?
to deposit cholesterol in peripheral tissues
LDL “low down dirty” bad cholesterol
what is a normal cholesterol range?
150-200
<200 low risk of CAD
200-400 mod risk of CAD
>240 high risk of CAD
what is a normal range of triglycerides?
40-160
>190 high risk of CAD
What is a normal range of LDL?
<100
130-159 mod risk for CAD
>160 high risk of CAD
What is a normal range of HDL?
> 40-50
60 low risk of CAD
<40 high risk of CAD
types of non-invasive procedures for CV disease
EGK/ECG
Holter monitor
Exercise stress test
Echocardiogram
what is the difference between a 12 lead EKG and telemetry?
EKG provides a more accurate picture of electroconductivity of the heart
What is a holter monitor
ambulatory EKG/ECG monitoring
what do you teach a patient prior to a holter monitor
test is painless
requires no prep
electrodes must stay firm against chest.
continue with usual activities
how long do patients wear a holter monitor?
24 hours
what is a holter monitor used for?
to dx atrial fib
what are some reasons a patient may wear a holter monitor?
syncope or tachycardia
what is an exercise stress/treadmill test used for?
to evaluate the hearts response to exercise
can use a treadmill or exercise bike
exercise may unmask symptoms of CAD or dysrhythmias in patients with minimal symptoms with normal activity
what must be continuously monitored during a exercise stress test?
heart monitoring and vital signs
is there special prep for an exercise stress test?
no, wear comfortable shoes and clothes
what are echocardiograms used for?
uses sound waves to create moving pictures of the heart to evaluate valves and chambers of the heart.
what does an echocardiogram measure?
ejection fraction
what do you teach a patient about an echocardiogram?
no prep
no radiation is used
painless
can be done at bedside
what is ejection fraction?
Percentage of blood pumped out of the left ventricle with each contraction.
what is a ejection fraction an indicator of?
effectiveness of the heart to pump
what is a normal ejection fraction?
55-70%
values less than 40% are seen with HF
types of invasive procedures of CV disease
trans-esophageal echocardiogram (TEE)
cardiac catheterization
Electrophysiology study (EPS)
What department is a TEE done in?
vascular lab
how is a TEE done?
a probe with an ultrasound inducer is placed down the throat with the end near the heart. Provides improved images, compared to an echo
contrast dye may be used
what type of sedation is used with a TEE?
requires IV access
can be local or conscious sedation
how long must a patient be NPO for a TEE?
6 hours
what must be removed from the patient prior to a TEE?
dentures
What must return before a patient can take anything by mouth after a TEE?
gag reflex
what symptom can be expected after a TEE?
sore throat
What does an EPS do?
evaluates the electrical health of the heart
induces dysrhythmia’s
confirms the root of the suspected electrical problem of the heart
what must be stopped several days before an EPS?
anti-dysrhythmics
how long must a patient be NPO before a EPS?
8 hours
What type of sedation is used for an EPS?
IV sedation
where are the catheters placed during a EPS?
near SA, AV nodes, and right ventricle
what must be checked frequently after a EPS?
VS
what is diagnostic use of cardiac catheterization with angiography “heart cath” used for?
to confirm location and extent of CAD
what is the therapeutic use of a heart cath?
to perform an intervention such as angioplasty/stent placement
what type of information does a heart cath provide?
about heart muscles, blood vessels and valves.
what path does a LT heart cath follow?
aorta RT coronary artery LT anterior descending coronary artery Circumflex coronary artery LT main coronary artery
what are the insertion sites of a heart cath?
neck or groin ( RT or LT femoral, radial, brachial artery)
angiogram
done during a heart cath
contrast dye injected through catheter and xray images are taken.
pt may feel a warm flush
nursing pre-procedure responsibilities of a heart cath
NPO (some may be allowed morning meds with small sip of water) consent signed pt/family teaching little pain will experience hot flash when dye injected check labs BUN/Cr empty bladder local anesthesia and IV sedation likely
nursing post-procedure responsibilities of a heart cath
will occur in cath lab or observation area
heparin drip will be d/c and clotting time monitored before sheath is pulled
when sheath removed apply pressure
bed rest
frequent circulation checks of extremities
check for pulses, color and sensation
what must be checked before the sheath can be removed following a heart cath?
clotting times
how long must you apply pressure after removing the sheath from a heart cath?
20 min
how long must a patient remain in bed after a heart cath and what position?
at least 6 hours with affected leg straight and HOB BELOW 30 degrees
potential complications of a heart cath?
bleeding (heparin drip used during procedure, monitor puncture site closely for hematoma)
emboli ( monitor for s/s of stroke)
infection
dysrhythmias
damage to heart (cardiac tamponade)
allergic reaction to dye
renal failure (r/t contrast dye “nephrotoxic”)
what is contrast nephrotoxicity?
AKI occurring within 3 days of contrast dye injection
major cause of AKI in hospitalized patients
what patient populations are at higher risk of contrast nephrotoxicity?
pre-existing renal impairment, diabetic, FVD patients
how do you prevent contrast nephrotoxicity?
sodium bicarb IV and acetylcysteine PO before and after procedure
force fluids
