Stress echocardiography- ASE guidelines

Ischemic heart disease (IHD) is on the rise and is the leading cause of death globally. Stress echocardiography is a standard test which routinely used for the detection of blockages in the coronary arteries in patients with symptoms such as exertional chest pain or shortness of breath.

It is a mature technique for the assessment of known or suspected IHD. It may be performed with either a treadmill or bicycle exercise or combined with a pharmacologic agent for the patient who is unable to complete an exercise protocol.

The advantages of stress echocardiography for the patient presenting with symptoms of potential cardiac origin are essential and can't be understated.

The American Society of Echocardiography (ASE) has updated its 2007 guidelines for using echocardiography to image ischemia. The older guidelines did not include class of recommendation and level of evidence, which are now included in this updated document, in addition to current practice recommendations and training requirements. The current guidelines include new recommendations regarding the quantitative analysis of stress echocardiography, including assessment of myocardial deformation with speckle tracking.

The guideline document is available on the Journal of American Society of Echocardiography (JASE) website OnlineJASE.com.

"Stress echocardiography is appropriate for evaluation of the patient presenting with symptoms of suspected ischemic heart disease," said the ASE's Chair of the writing group, Patricia Pellikka, M.D., FACC, FAHA, FASE, of Mayo Clinic in Rochester, Minn. "In addition to detecting ischemia, stress echo can reveal diastolic dysfunction, pulmonary hypertension, valvular disease, and other cardiac causes of symptoms. Stress echo is also useful in periodic assessment of children at risk of ischemia, such as those who have undergone a heart transplant or with Kawasaki Disease. Exercise stress echocardiography is particularly well-tolerated by all patients who can exercise."

She added, "Comparative studies of stress echocardiography versus other modalities have not taken into account the incremental value of the ancillary findings detected by echocardiography at the time of stress echocardiography, including detection of non-ischemic causes of cardiac symptoms."

Key Points

1. For treadmill exercise protocols, images obtained at rest and immediately after exercise should be compared side-by-side using the quad-screen format.

2. For pharmacologic stress echocardiography, images from peak stress stages should be compared to rest, low dose, and pre-peak or early recovery stages using the quad-screen format.

3. Obtaining data from multiple cardiac cycles at peak stress enhances the accuracy of test interpretation. For the continuous recording of rest and stress images, the use of digital recordings software is preferable to recording on videotape.

Major recommendations-

1. UEAs should be utilized during stress echocardiography when-ever two or more contiguous segments cannot be visualized or a coronary artery territory cannot be completely visualized

2. The use of very low dose bolus injections (0.1 ml of Definity, 0.2-0.4 ml of Optison, and 0.5-1.0 ml of Lumason) followed by slow saline flushes is optimal for reducing cavity shadowing.

3. Alternatively, Definity has been given as a 3-5% dilution in normal saline, and Optison has been infused as a 10% dilution.

4. VLMI imaging pulse sequence schemes that detect non-linear fundamental frequency responses at <0.2 MI are recommended for optimal LVO and reduced basal segment attenuation

5. Exercise stress tests are more physiologic than pharmacologic stress tests and include the prognostically important finding of the patient's exercise capacity. Thus, if a patient can exercise, this is the preferred stress modality.

6. Bicycle stress echocardiography (upright or supine) is technically more feasible for the assessment of both coronary flow reserve and diastology.

7. DSE is a preferred alternative test for the evaluation of myocardial ischemia when a patient cannot exercise.

8. Diagnostic endpoints include achievement of at least 80% of the age- and sex-predicted workload for exercise testing and target HR for DSE.

9. The RV free wall should be included in apical 4-chamber images for assessment of lateral wall and tricuspid annular motion when the right CAD is suspected. The right ventricular lateral wall and tricuspid annular motion should be assessed for the detection of RV ischemia. (Level of evidence I, class of recommendation B)

10. Patients who experience hypertensive responses to stress should be evaluated or managed like any patient who has positive stress findings.

11. The outcomes of patients with false-positive stress results are similar to those with true-positive results. Patients with false-positive results on stress echocardiograms should receive intensive risk factor management and careful follow-up.

12. When properly performed, perfusion imaging with VLMI imaging (RTMCE) appears to improve the detection of coronary artery stenoses during DSE or vasodilator stress imaging. If perform- ing myocardial perfusion imaging, VLMI imaging should be used with real-time high MI flash replenishment techniques for simultaneous perfusion and wall motion assessment (Level of Evidence IIa, Class of Recommendation B).

13. ESE or DSE are appropriate for the evaluation of the patient presenting with exertional dyspnea. In addition to detecting ischemia, diastolic dysfunction, pulmonary hypertension and other cardiac causes of this symptom can be readily detected.

14.. ESE or DSE may be used for detection of ischemia and risk stratification in patients with LBBB

15. In LBBB, stress echocardiography allows recognition of nonischemic conditions also associated with LBBB.

16. In patients in whom preoperative stress testing is appropriate before noncardiac surgery, a normal DSE has been shown to be associated with an excellent outcome whereas a positive study is associated with peri-operative events.

17. The heart rate at which ischemia develops during DSE can be used for risk stratification.

18. When properly performed, perfusion imaging with RTMCE improves the prognostic value of bicycle, dobutamine, and vasodilator stress echocardiography.

19. VLMI multi-pulse imaging with UEAs is preferred over low MI imaging to improve the detection of regional wall motion abnormalities.

For more details, read the full study on the following link

Patricia A. Pellikka, Adelaide Arruda-Olson, Farooq A. Chaudhry, et al. Guidelines for Performance, Interpretation, and Application of Stress Echocardiography in Ischemic Heart Disease: From the American Society of Echocardiography. JASE, Vol. 33, Issue 1, p1–41.e8. DOI: https://doi.org/10.1016/j.echo.2019.07.001