Diagnostic Tests Flashcards
Holter Monitor
- Patient Activated monitor:
– Hit button when feel Sx - Indication: pt with syncope, dizziness, intermittent symptoms
- Pt keeps a 24 hr diary
– 1-3 days duration - Diagnosis and manage symptomatic arrhythmias
– Rest and with Ex - ECG for entire length of time
How is a resting ECG different from a 12 lead exercise ECG?
The Right and Left Foot are in different places.
Resting ECG: On actual eet
Exercise: On the ribs
What abnormalities might someone see on a resting ECG?
- Identify Ischemia
– ST depression - Identify injury
- MI
- Arrhythmias
– Afib; SVT; Vtach; Vfib
– Aflutter; AV blocks
What is a GXT?
- Incremental exercise test
- Treadmill or bike/cycle
- 12 lead ECG
- HR, BP, RPE monitored at each stage
- Maximal or Symptom limited
- Sub-max
What is the GXT used for?
- Evaluate cardiac symptoms
- Evaluate effects of medical / surgical intervention
- Evaluate arrhythmias & hemodynamic response to ex
- Determine Exercise prescription
What is done in an electrophysiological study?
- Catheter inserted groin, up to the heart
- Electrical signals are sent to the heart; evaluate the SA node and the conduction pathways
- Dysrhythmia may be induced
– Meds given to stop & evaluate effectiveness of the meds - Mapping to locate the spot where a dysrhythmia starts
– If found an ablation (freezing or radiofrequency) can be done
When is an ablation indicated?
- SVT, A fib and A flutter
- Goal is to remove ectopic foci (scar tissue doesn’t allow signal)
- Radiofrequency ablation
What tests can be done to test for ischemia?
- Resting ECG
- Exercise ECG (stress test)
- Angiography
- Radioactive Nuclide Perfusion testing
- Pharmacological stress testing
- MRI
What can cause ischemia?
Vasospasm or artherosclerosis
What is an angiogram and what does it look at?
- A long thin flexible catheter is inserted through femoral artery up to heart (Sometimes brachial artery is used)
- Goal: establish or confirm Dx of CAD
- X-rays are taken of heart chambers and coronary arteries
- Data on R coronary, L main, LAD & Circumflex circulation
- Radio-opaque contrast material is injected into heart chamber or coronary arteries
What is a Thallium Stress Test?
- Use isotope Thallium to evaluate coronary artery perfusion (blood flow)
- EKG and treadmill
- Two phases: Pre and during exercise (isotope injected near peak)
- Evaluate perfusion of the heart = IPE
A Thallium Stress Test is performed, an area of the heart perfused at rest but not during exercise (IPE), what does that tell you
IPE: Immediate post exercise
It is transient ischemia
A Thallium Stress Test is performed, no areas of the heart perfused at rest nor during exercise (IPE). What does that mean?
MI with scarring
What is the alternative test to Thallium Stress Test for those that cannot exercise? What does it do?
Persantine-Thallium Stress Test
Persantine helps to expand the coronary arteries (similar to exercise)
How is the Thallium Stress Test and GXT Stress Test different?
Thallium is similar but also uses additional information by using the isotope Thallium to evaluate coronary blood flow.
What is an echocardiography?
- Noninvasive
- Ultrasound of heart through the intercostal space
- Looks at the size, struture and function of the heart, chambers and valves
What is a Transesophageal Echo and how is it different than ultrasound?
- Thin flexible tube (special tip) inserted down throat. Anethetic applied to inhibit gag reflex. Tip sends out an ultrasound wave
- It is different because of location and you get a much clearer image
What is a stress echo?
- Echo and Treadmill Stress Test
- Echo done at rest and again at peak heart rate
- Looking at wall motion, chamber size, wall thickness and valves
What is a Dobutamine Stress Echo?
- Evaluate heart movement, valves and chambers for those who can’t exercise on treadmill
- Dobutamine – medication to increase HR and BP similar to ex
What is a carotid ultrasound measure?
Diameter and velocity
Tilt Table Test
- Done with pt’s with syncope
- Point is to cause symptoms they were having before
- Increase to 80 degrees
- If they can get to 80 degrees will be given glyceryl trinitrate to drop BP and more likely to have symptoms
Oximetry - Values
- Normal 98-100%
- If drops below 90% with exercise – evaluate situation
- PaO2 >80 mm Hg ~ SpO2 >93 - 95%
- PaO2 <60 mm Hg ~ SpO2 <88 - 90%
NEED TO KNOW; REALIZE RELATIONSHIP BETWEEN PRESSURE AND O2 SAT
What is a PCI?
- Percutaneous Coronary Innervention
- Performed when stenotic lesion is not too large (~>70%) occluded
- Catheterization; Change tip on catheter with balloon and inflate the balloon where the obstruction is to try to push the atherosclerosis along the line of flow
How common is restenosis after a PCI?
Within the first 6 months:
* Restenosis of 32-42% with no Stent
* Restenosis less than 10% with Stent
