In 2013, in its "Exercise Standards for Testing and Training", the AHA indicated that high frequency QRS analysis during ECG treadmill test have useful test performance for detection of coronary heart disease. Perfusion stress test (with 99mTc labelled sestamibi) is appropriate for select patients, especially those with an abnormal resting electrocardiogram. Intracoronary ultrasound or angiogram can provide more information at the risk of complications associated with cardiac catheterization. Diagnostic value
The common approach for stress testing by American College of Cardiology and American Heart Association indicates the following:
Treadmill test: sensitivity 73-90%, specificity 50-74% (modified Bruce protocol)
Nuclear test: sensitivity 81%, specificity 85-95%(Sensitivity is the percentage of people with the condition who are correctly identified by the test as having the condition; specificity is the percentage of people without the condition are correctly identified by the test as not having the condition). To arrive at the patients posttest likelihood of disease, interpretation of the stress test result requires integration of the patients pretest likelihood with the tests sensitivity and specificity. This approach, first described by Diamond and Forrester in the 1970s, results in an estimate of the patients post-test likelihood of disease. The value of stress tests has always been recognized as limited in assessing heart disease such as atherosclerosis, a condition which mainly produces wall thickening and enlargement of the arteries.
more than 2 mm horizontal or downsloping ST segment depression in non-Q wave leads, or marked axis shift
Arrhythmias other than sustained ventricular tachycardia e.g. Premature ventricular contractions, both multifocal or triplet; heart block; supraventricular tachycardia or bradyarrhythmias
Intraventricular conduction delay or bundle branch block or that cannot be distinguished from ventricular tachycardia
Increasing chest pain
Fatigue, shortness of breath, wheezing, claudication or leg cramps
Hypertensive response (systolic blood pressure > 250 mmHg or diastolic blood pressure > 115 mmHg)

Adverse effects
Side effects from cardiac stress testing may include
Palpitations, chest pain, myocardial infarction, shortness of breath, headache, nausea or fatigue. Adenosine and dipyridamole can cause mild hypotension. As the tracers used for this test are carcinogenic, frequent use of these tests carries a small risk of cancer. Pharmacological agents
Pharmacologic stress testing relies on coronary steal. Vasodilators are used to dilate coronary vessels, which causes increased blood velocity and flow rate in normal vessels and less of a response in stenotic vessels. This difference in response leads to a steal of flow and perfusion defects appear in cardiac nuclear scans or as ST-segment changes.The choice of pharmacologic stress agents used in the test depends on factors such as potential drug interactions with other treatments and concomitant diseases. Pharmacologic agents such as adenosine, Lexiscan (regadenoson), or dipyridamole is generally used when a patient cannot achieve adequate work level with treadmill exercise, or has poorly controlled hypertension or left bundle branch block.