Cardiac Diagnostic Studies Lecture Powerpoint Flashcards
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Most important tool in evaluating cardiac patient
History and physical
10 year old experiencing palpitations suddenly, what are the 5 big tests would you order for diagnosis?
- EKG #1
- Echocardiogram
- Holter monitor
- Event recording
- Symptom diary and pulse checks
Holter Monitor definition and one big disadvantage
5 lead EKG recording that records every heartbeat up to 48 hours, provides avg heart rate as well as minimum and max heart rate, patients should self record symptomatic moments to correlate to the arrhythmia
-Disadvantage: short time frame relatively speaking so many patients will not have symptoms
Holter Monitor indications
-Evaluate symptoms such as palpitations, chest pain, syncope caused by dysrythmia, or evaluate medical therapy being used to suppress dysrhythmia
Event recorders definition and one big disadvantage
- Devices that continously monitor ECGs for 30-60 days, device has a memory that will store a triggered event (regardlss of if patient is aware or if patient triggers device manually) as well as the previous 10 minutes
- Disadvantage is that patient must wear for a month and change patches
Event recorders indications
Suspected dysrhythmia not occurring on a daily basis
Implantable cardiac monitor
Implanted on upper chest wall subcutaneously, hand held device activator placed over device to mark and save rhythms before, during, and after event, new models can automatically send transmission to physician
Tilt table test
Older test that is used for evaluation of vasovagal syncope opposed to a cardiac syncope, thru strapping patient to table that moves from horizontal to vertical position while monitoring heart rate and blood pressure and assessing for syncope
65 year old presenting to cardiologist complaining of intermittent dyspnea related to activity, what are 4 tests you would order?
- EKG
- Echocardiogram
- Stress Test
- Chest X ray
Echocardiography and 3 subtypes
- 2D mapping allows for evaluation of anatomy, hemodynamics, function of cardiac structures, assessment for clot presence, tumor, or pericardial effusion
- Transthoracic echo, transesophageal echo, or doppler
White on an echocardiogram represents ____ and black represents ___
muscle, lumen
Doppler imaging
A continuous wave doppler that can measure the velocity of the fluid in the heart helpful in diagnosing stenosis or other conditions (color flow mapping)
Benefits and limitations of echocardiography
Benefits - non invasive, inexpesnive, mobile
Limitations - poor windows, technologist dependent, subjective interpretations by physicians
Poor windows
Refers to when there is extra tissue (adipose, muscle, etc) that makes it difficult to obtain clear echocardiogram images
65 male with mildly elevated cholesterol presents with chest tightness when walking, what 4 tests do you order?
- EKG
- echocardiogram
- exercise stress test
- Holter monitor
Cardiac stress testing and 2 ways to enhance the study
Goal is to evaluate perfusion/function of myocardium at times of stress (exercise induced or pharmacologically induced) that can evaluate exercise intolerance or rhythm abnormalities, can evaluate for ST segment changes, BP response, maximum achieved predicted HR
-enhanced with imaging studies such as echocardiogram or nuclear imaging
Stress test indications (4)
- Evaluate patients with known or suspected CHD
- assess therapeutic effects of drugs
- post MI
- Preop risk assessment
Exercise stress tests without imaging advantages and disadvantages
Advantages - assessment of ischemia, equipment widely available
Disadvantages - Sensitivity lower than that of stress imaging techniques, female population not as accurate
Absolute and relative contraindications for exercise testing
Absolute - recent MI, unstable angina, acute aortic dissection or PE
Relative - Left coronary artery stenosis, electrolyte abnormalities, mental or physical impairment
Stress test Echocardiography advantages and disadvantages
Advantages - Useful for diagnosing CAD, provides immediate results
Disadvantages - interpretation subjective and not standardized, images may be nondiagnostic
Pharmacological alternatives to treadmill for stress testing (3)
- Dobutamine
- Adenosine
- Persantine
Dobutamine stress testing function
Prominent inoropic and less prominent chronotropic effects on myocardium that increases heart rate, blood pressure, and contractility closely simulating exercise, up titrated as infusion to achieve max acheived predicted HR
Adenosine stress testing function
Coronary vasodilator that decreases blood pressure but has no effect on HR, can cause transient heart block or induce bronchospasm, can accurately assess CAD in patients unable to exercise and is relatively safe with side effects that can be rapidly reversed
Nuclear stress test (perfusion imaging)
Involves nuclear isotope with an affinity for the heart is injected, ischemic areas will have decreased uptake and infarcted will have none, highly sensitive for coronary artery disease as it directly measures PERFUSION
Interpreting nuclear stress test
Compare rest image with stress image, if defect present at stress and rest then that indicates previous MI in the artery of the region
Cardiac catheterization
Angiogram that allows for location of stenosis or aneurysm in blood vessels, allows to assess hemodynamics, pressure in heart and lungs, biopsy, and identify congenital heart defects
Cardiac catheterization risks (4)
- bruising
- stroke
- arrhythmia
- dye can have allergic rxn
Cardiac MRI
Examines size of heart chambers and thickness of the wall and other anatomy, determines extent of damage caused by heart attack or progressive heart disease, detects plaque buildup, assesses a patients recovery following treatment
Teens with chest pain and elevated troponin levels indicates ____ for which the study of choice to image is ____
Viral myocarditis, cardiac MRI
Benefits and drawbacks of cardiac MRI
Benefits - 3D analysis, non invasive, no radiation
Drawbacks - no pacemakers, only diagnostic not therapeutic
Nuclear stress test is directly measuring ____
perfusion
Cardiac CT angiogram
Uses CT and IV contrast to obtain 3D images of heart and great vessels, enable visualization of plaque or ca2+ deposits on artery walls, noninvasive method to detect blockages
Cardiac CT angiogram benefits and drawbacks
Benefits - 3D, noninvasive analysis, superior to catheter angiography
Drawbacks - Radiation exposure, diagnostic not therapeutic, risk of contrast allergy
Electrophysiology study
Tests function of heart’s electrical system, can be useful in identifying an arrhythmia and helping decide best therapy for it especially when there is risk for future cardiac events
Risks and benefits of electrophysiology study
Benefits - may be able to cure arrhythmia via ablation
Risks - bleeding, infection, injury
Calcium score screening CT
Method for predicting risk for CAD in asymptomatic patient by detecting Ca2+ buildup, quick screening tool but may miss some plaques and gives radiation exposure
