TN 48 (11-94)
DI 32594.020 Evaluating the Results of Tests
Consider results of a test in context with all symptoms, signs, other laboratory findings, and any medical opinions.
1. Coronary arteriogram
Generally, the arteriogram is superior to the ET for establishing the diagnosis of IHD and extent of coronary artery obstruction, while the ET is superior to the arteriogram for estimating functional loss. However, neither the results of an arteriogram, nor the results of an ET necessarily correlates accurately with the true degree of a claimant's functional loss. For this reason, all evidence must be considered.
Useful with clinical assessment to determine the feasibility of and need for revascularization procedures.
Defines structural or anatomical abnormalities.
2. Myocardial perfusion scan (thallium stress test)
The myocardial perfusion scan (thallium stress test):
Images regional myocardial blood flow.
May provide data useful for confirming ischemia.
May be useful for assessing severity (e.g., a positive stress thallium study at a low workload indicates substantial restriction of exertional capacity).
3. Ventriculography (radionuclide MUGA scans and echocardiography)
Ventriculography (radionuclide MUGA scan and echocardiography):
Provides information on heart chamber size and valve anatomy.
Provides data on ejection fraction (EF) and ventricular function.
Detects ventricular wall motion abnormalities resulting from ischemia or necrosis of myocardium.
Detects abnormalities such as cardiomyopathies and intracardiac tumors or masses.
May be useful for assessing severity (e.g., a fall in EF on exercise at a low workload indicates substantial restrictions of exertional capacity).
4. Ambulatory electrocardiogram monitoring (e.g., holter monitor)
Ambulatory electrocardiogram monitoring (e.g., Holter Monitor):
Provides a record to determine presence of dysrhythmias.
May provide suggestive evidence for ischemia.
5. Exercise test
The Exercise Test:
Markedly limited peak aerobic capacity (i.e., 5 METs or less) is useful for the identification and allowance of individuals who are so functionally impaired they cannot be expected to work.
A TET (or other exercise ECG modality) should be considered along with all other evidence in determining the severity of the impairment(s). Adjudicators may not place exclusive weight on the results of an ET in denying (or ceasing) a claim.
The ET is valuable for estimating maximal aerobic capacity in an individual with a cardiovascular impairment. However, for a number of reasons, there are limits to the use and reliability of the ET in evaluating an individual's ability to perform work-related activities. These include:
The ET has a substantial incidence of false negative results indicating no IHD in some individuals who actually have this disorder. Furthermore, the ET has a certain incidence of false positive results indicating ischemia in some individuals who actually do not have this disorder.
Individuals with regional dyskinesia may demonstrate an elevation of the ST segment that cancels the ischemic depression of the ST segment.
The TET provides an estimate of aerobic capacity for walking on a grade in an environmentally controlled laboratory. Therefore, TET results do not correlate with the ability to perform several other types of exertional activities and do not provide an estimate of ability to perform throughout a workday activities required for gainful work in all possible work environments. A TET (or other ECG modality) is not to be relied on as the sole basis for rejecting a claim. You must consider other signs, symptoms, laboratory findings, environmental restrictions, susceptibility to psychological stress, or other evidence that may establish the claimant's disability.