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Therefore, based on current data, diagnostic stress testing is recommended for patients with a low to moderate pretest probability of CAD but is unlikely to be helpful in those at very low risk or high risk
==Background==


ECG-Based Exercise Treadmill Testing
*Stress testing is recommended for patients with low-moderate pretest probability of CAD
The most commonly used definition of a positive exercise test result from an ECG standpoint is 1 mm of horizontal or downsloping ST-segment depression or elevation for at least 60 to 80 milliseconds after the end of the QRS complex.
**Not helpful in patients with very low risk or high risk


Table 55-5 Contraindications to Exercise Testing
==ECG-Based Exercise Treadmill Testing==


Absolute
*68% sn, 77% sp<ref>Gianrossi R, Detrano R, Mulvihill D, Lehmann K, Dubach P, Colombo A, McArthur  D, Froelicher V. Exercise-induced ST depression in the diagnosis of coronary artery disease. A meta-analysis. Circulation. 1989 Jul;80(1):87-98.</ref>
  Acute myocardial infarction (within 2 d)
*Contraindications to Exercise Testing
  High-risk unstable angina
**Absolute  
  Uncontrolled cardiac dysrhythmias causing symptoms or hemodynamic compromise
***[[Myocardial infarction]] (within 2 days)  
  Symptomatic severe aortic stenosis
***High-risk unstable angina  
  Uncontrolled symptomatic heart failure
***Uncontrolled cardiac dysrhythmias  
  Acute pulmonary embolus or pulmonary infarction
***Symptomatic aortic stenosis  
  Acute myocarditis or pericarditis
***Uncontrolled symptomatic heart failure  
  Acute aortic dissection
***Acute pulmonary embolus or pulmonary infarction  
Relative*
***Acute myocarditis or pericarditis  
  Left main coronary stenosis
***Acute aortic dissection  
  Moderate stenotic valvular heart disease
**Relative  
  Electrolyte abnormalities
***Baseline ST segment abnormalities
  Severe arterial hypertension (>200 mm Hg systolic, >110 mm Hg diastolic)
***Left main coronary stenosis  
  Tachydysrhythmias or bradydysrhythmias
***Moderate stenotic valvular heart disease  
  Hypertrophic cardiomyopathy and other forms of outflow tract obstruction
***Electrolyte abnormalities  
  Mental or physical impairment leading to inability to exercise adequately
***Severe hypertension (>200 sys, >110 dia)  
  High-degree atrioventricular block
***Tachydysrhythmias or bradydysrhythmias  
***HOCM
***Mental or physical impairment  
***High-degree atrioventricular block


<br>


Echocardiography
*The Bottom Line:
. Advantages of stress echocardiography over exercise treadmill testing are its higher sensitivity and specificity for significant coronary disease and nondependence on the ECG.
**ETT has low sensitivity and specificity overall (especially for women) and as such is not a good test for patients in whom suspicion for ACS is high
**ETT is safe in low-risk and select intermediate-risk patients as a way of determining who is at low risk for short term adverse events (and therefore can go home)
**ETT does not have prognostic value for patients who return to the ED with concerning symptoms or ECG changes


Overall, stress echocardiography is associated with 80% sensitivity and 84% specificity when evaluating for significant coronary disease.55 Thus, it is superior to ECG-based stress testing. When evaluated among low-risk ED patients, three studies have reported NPVs for subsequent cardiac events to be 97% to 100%, comparable to that of stress testing using nuclear imaging techniques.54
==Stress Echocardiography==


*Sn 80% sp 84%
**When used in low-risk patients, NPV 97-100%


Nuclear Medicine
*Who should be tested (ACC/AHA Class IIa)<br>
**patients with abnormal baseline ECG
**patients unable to exercise
**women with low- to intermediate-risk


*Who shouldn’t be tested with stress echo
**patients in whom a sub-optimal study is likely (very obese, COPD with expanded AP chest diameter, etc)
**patients with grossly abnormal baseline LV or valvular function (e.g. severe AS)


Combined with conventional ECG-based stress testing, thallium imaging offers improved sensitivity and specificity for detection of significant CAD over ECG-based testing alone. Furthermore, thallium testing (or other perfusion imaging) is likely to be of value in patients who would not otherwise benefit from stress testing due to a confounding or potentially masking abnormal baseline ECG.
<br>


*The Bottom Line
**Stress echocardiography (chemical or exercise induced) has greater sensitivity and specificity than ETT for ACS (especially for women)
**Patients with normal stress echos are at very low risk for mortality within 1 year
**A normal stress echo does not preclude subsequent ACS, nor should it lower suspicion for ACS when a patient presents with new symptoms!


<br>


==Cardiac Radionuclide Imaging==


Nuclear myocardial perfusion imaging is generally appropriate in patients with acute chest pain in which the diagnosis of acute coronary syndrome is unclear, to determine whether or not cardiac catheterization is indicated, or to determine prognosis. Appropriate Use Criteria (AUC) has been developed by the American College of Cardiology and is updated regularly. <ref>Hendel RC, Berman DS, Di Carli MF et al. ACCF/ASNC/ACR/AHA/ASE/SCCT/SCMR/SNM 2009 Appropriate Use Criteria for Cardiac Radionuclide Imaging: A Report of the American College of Cardiology Foundation Appropriate Use Criteria Task Force, the American Society of Nuclear Cardiology, the American College of Radiology, the American Heart Association, the American Society of Echocardiography, the Society of Cardiovascular Computed Tomography, the Society for Cardiovascular Magnetic Resonance, and the Society of Nuclear Medicine. [http://content.onlinejacc.org/article.aspx?articleid=1139755 J Am Coll Cardiol. 2009 Jun 9;53(23):2201-29.]</ref>. Absolute contraindications to stress testing include acute myocardial infarction (within 2 days), unstable angina, and symptomatic heart failure. <ref>Gibbons RJ, Balady GJ, Beasley JW et al.  ACC/AHA guidelines for exercise testing: executive summary. A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Committee on Exercise Testing). [http://circ.ahajournals.org/content/96/1/345.long Circulation. 1997 Jul 1;96(1):345-54.]</ref>. The decision to perform nuclear myocardial perfusion imaging or stress echo imaging generally depends upon local expertise. The benefit of nuclear imaging is that it can be performed in nearly 100% of patients, whereas echo stress testing is more limited by body habitus and the ability to obtain good imaging windows quickly after stressing the patient. The benefit of echo stress testing is lower costs and no radiation exposure. The amount of radiation exposure from a stress-rest nuclear myocardial perfusion scan is typically 10 mSv or less for gamma camera based imaging (similar to a chest CT), and under 5 mSv for PET imaging.




*PATIENTS WITH ACUTE CHEST PAIN: APPROPRIATE INDICATIONS
**Patients with acute chest pain with possible acute coronary syndrome: a) ECG shows no ischemic changes, LBBB, or electronically ventricular paced rhythm; and b) negative to borderline elevated [[troponin]] levels.
**In this setting, nuclear imaging is considered appropriate in both low-risk TIMI score and high-risk TIMI score patients


*PATIENTS WITH ACUTE CHEST PAIN: INAPPROPRIATE INDICATIONS
**Patients with definite acute coronary syndrome
**Early stress testing contraindicated within 2 days after myocardial infarction


==Sensitivities/Specificities==
*THE BOTTOM LINE
TREADMILL: sens spec
**Asymptomatic patients in need of risk stratification typically will undergo exercise ECG testing only. Imaging is indicated only when the ECG is uninterpretable, the patient is unable to adequately exercise, or the pretest probability is intermediate or high.
**Symptomatic patients with an uncertain diagnosis of acute coronary syndrome frequently undergo a stress imaging procedure first, then depending upon the result, may or may not undergo cardiac catheterization.
**The decision regarding stress nuclear versus stress echo is usually made based upon availability of local expertise.


Overall 68% 77%
==See Also==
*[[Acute Coronary Syndrome (Main)]]


ED 90% 50%
==References==
<references/>


[[Category:Cardiology]]
 
SPECT
 
Overall 88% 77%
 
ED 86% 74%
 
 
ECHO
 
Overall 76% 88%
 
ED 47% 99%
 
which test to use?
 
 
ETT- no baseline ST segment abnormalities (no LBBB LVH w/strain), no digoxin use, Beta blockers and CCB ok...and if a negative result will just meant the person is going to get the next test...
 
==Def of a positive treadmill:==
#>1mm horizontal or downsloping ST segment depression or elevation at 80ms after J point
#significant arrythmias
#decreased systolic BP of > 10 mmHg
#significant symptoms
 
a negative stress test has @ 98% negative predictive value.
 
does a postive stress mandate admission? not necessarily (yes at Harbor), the following are predictive of L main disease or severe multi vessel disease:
 
#ST depression > 2.5mm
#serious ventricular arrythmias
#ST depression within 3 minutes of beginning
#prolonged >8 minute ST segment recovery
#hypotension >10mmHb during test or diastolic HTN >110 during test.
 
these either need admission or at least a discussion with a cardiologist.
 
==Utility of past tests==
Angiography- if normal, progrssion to greater than 50% occlusion is unlikely within five years.
 
if <50% occlusion, about 30% progress to >50% obstruction at 3 years.
 
the change in chest pain and risk factors is predictive of progression (a diabetic with BS OOC not taking his/her lipid meds can accelerate much faster than your ordinary guy that does everything he should be doing...)
 
SPECT or EST-
 
<1% cardiac event rate at one year in patients with normal tests.
 
Bottom line:some low risk patients (10%) will have an adverse event within 31 months of initial evaluation, these are most likely the "higher risk" segment of the low risk population and therefore are quite likely to have some outpatient testing done within the next 31 months.
 
10 mets good 10 yr prognosis
 
85% max hr is adequate est
 
==ECG Stress Testing==
===Protocol===
#need to reach 85- 100% maximum heart rate
#max heart rate is 220- age
#exercise capacity reported in minutes or met eq of ox consumption
#test is adequate if >6 METs reported
#test stopped when target heart rate reached
#test also stopped if BP decrease more than 10mm, sustained v- tach, st elevation >1mm, chest pain, dizziness.
#relative stop indications- st depression >2mm, arr, BP>250/115, claudication, SOB, BBB
#Positive test if horizontal or downsloping st depression >1mm for 60 - 80ms, inappr slow heart rate, decrease in BP, sust V tach, st elevation
##if positive then need angio
##if equivocal- do stress echg or nuclear scan
##no beta blockers, ca channel blockers or nitrates
 
==Source ==
6/06 MISTRY
 
[[Category:Cards]]

Latest revision as of 11:58, 5 January 2020

Background

  • Stress testing is recommended for patients with low-moderate pretest probability of CAD
    • Not helpful in patients with very low risk or high risk

ECG-Based Exercise Treadmill Testing

  • 68% sn, 77% sp[1]
  • Contraindications to Exercise Testing
    • Absolute
      • Myocardial infarction (within 2 days)
      • High-risk unstable angina
      • Uncontrolled cardiac dysrhythmias
      • Symptomatic aortic stenosis
      • Uncontrolled symptomatic heart failure
      • Acute pulmonary embolus or pulmonary infarction
      • Acute myocarditis or pericarditis
      • Acute aortic dissection
    • Relative
      • Baseline ST segment abnormalities
      • Left main coronary stenosis
      • Moderate stenotic valvular heart disease
      • Electrolyte abnormalities
      • Severe hypertension (>200 sys, >110 dia)
      • Tachydysrhythmias or bradydysrhythmias
      • HOCM
      • Mental or physical impairment
      • High-degree atrioventricular block


  • The Bottom Line:
    • ETT has low sensitivity and specificity overall (especially for women) and as such is not a good test for patients in whom suspicion for ACS is high
    • ETT is safe in low-risk and select intermediate-risk patients as a way of determining who is at low risk for short term adverse events (and therefore can go home)
    • ETT does not have prognostic value for patients who return to the ED with concerning symptoms or ECG changes

Stress Echocardiography

  • Sn 80% sp 84%
    • When used in low-risk patients, NPV 97-100%
  • Who should be tested (ACC/AHA Class IIa)
    • patients with abnormal baseline ECG
    • patients unable to exercise
    • women with low- to intermediate-risk
  • Who shouldn’t be tested with stress echo
    • patients in whom a sub-optimal study is likely (very obese, COPD with expanded AP chest diameter, etc)
    • patients with grossly abnormal baseline LV or valvular function (e.g. severe AS)


  • The Bottom Line
    • Stress echocardiography (chemical or exercise induced) has greater sensitivity and specificity than ETT for ACS (especially for women)
    • Patients with normal stress echos are at very low risk for mortality within 1 year
    • A normal stress echo does not preclude subsequent ACS, nor should it lower suspicion for ACS when a patient presents with new symptoms!


Cardiac Radionuclide Imaging

Nuclear myocardial perfusion imaging is generally appropriate in patients with acute chest pain in which the diagnosis of acute coronary syndrome is unclear, to determine whether or not cardiac catheterization is indicated, or to determine prognosis. Appropriate Use Criteria (AUC) has been developed by the American College of Cardiology and is updated regularly. [2]. Absolute contraindications to stress testing include acute myocardial infarction (within 2 days), unstable angina, and symptomatic heart failure. [3]. The decision to perform nuclear myocardial perfusion imaging or stress echo imaging generally depends upon local expertise. The benefit of nuclear imaging is that it can be performed in nearly 100% of patients, whereas echo stress testing is more limited by body habitus and the ability to obtain good imaging windows quickly after stressing the patient. The benefit of echo stress testing is lower costs and no radiation exposure. The amount of radiation exposure from a stress-rest nuclear myocardial perfusion scan is typically 10 mSv or less for gamma camera based imaging (similar to a chest CT), and under 5 mSv for PET imaging.


  • PATIENTS WITH ACUTE CHEST PAIN: APPROPRIATE INDICATIONS
    • Patients with acute chest pain with possible acute coronary syndrome: a) ECG shows no ischemic changes, LBBB, or electronically ventricular paced rhythm; and b) negative to borderline elevated troponin levels.
    • In this setting, nuclear imaging is considered appropriate in both low-risk TIMI score and high-risk TIMI score patients
  • PATIENTS WITH ACUTE CHEST PAIN: INAPPROPRIATE INDICATIONS
    • Patients with definite acute coronary syndrome
    • Early stress testing contraindicated within 2 days after myocardial infarction
  • THE BOTTOM LINE
    • Asymptomatic patients in need of risk stratification typically will undergo exercise ECG testing only. Imaging is indicated only when the ECG is uninterpretable, the patient is unable to adequately exercise, or the pretest probability is intermediate or high.
    • Symptomatic patients with an uncertain diagnosis of acute coronary syndrome frequently undergo a stress imaging procedure first, then depending upon the result, may or may not undergo cardiac catheterization.
    • The decision regarding stress nuclear versus stress echo is usually made based upon availability of local expertise.

See Also

References

  1. ↑ Gianrossi R, Detrano R, Mulvihill D, Lehmann K, Dubach P, Colombo A, McArthur D, Froelicher V. Exercise-induced ST depression in the diagnosis of coronary artery disease. A meta-analysis. Circulation. 1989 Jul;80(1):87-98.
  2. ↑ Hendel RC, Berman DS, Di Carli MF et al. ACCF/ASNC/ACR/AHA/ASE/SCCT/SCMR/SNM 2009 Appropriate Use Criteria for Cardiac Radionuclide Imaging: A Report of the American College of Cardiology Foundation Appropriate Use Criteria Task Force, the American Society of Nuclear Cardiology, the American College of Radiology, the American Heart Association, the American Society of Echocardiography, the Society of Cardiovascular Computed Tomography, the Society for Cardiovascular Magnetic Resonance, and the Society of Nuclear Medicine. J Am Coll Cardiol. 2009 Jun 9;53(23):2201-29.
  3. ↑ Gibbons RJ, Balady GJ, Beasley JW et al. ACC/AHA guidelines for exercise testing: executive summary. A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Committee on Exercise Testing). Circulation. 1997 Jul 1;96(1):345-54.
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