Provocative Testing in ACS
No risk
No test.
Even an exercise ECG is dangerous in these people because a false positive will lead to an Angiogram which may lead to a stroke, dissection, renal failure, cancer. Whilst these complications are unlikely if they just don't have the disease clinically then no test is indicated.Low risk
Male with exercise ability
Exercise ECG generally the appropriate test.
Recurrent presentations depsite negative EST or unable to exercise
Cardiac CT gives lower rates of people coming back with undifferentiated chest pain.. Once you have seen the arteries are normal you can feel more confident. Here this is only available as an outpatient (medicare) test. Radiology will provide same day or next business day test. Order must include consultant provider number and signature.
Remember, while it has a high sensitivity for significant stenoses ot has a much lower specificity so false positives are a problem in this group. Really it is better as an intermediate risk patient test but it might help with the repeat visitors.
Low risk female
Stress ECHO test of choice.
Too many false positives with exercise ECG and too much breast radiation with cardiac CT .
Intermediate risk
Young patient
Stress ECHO.
Older patient
Cardiac CT and/or thallium. The combination of CTCA, followed by thallium if positive, helps to sort out who has lesions that are meaningful although there is some uncertainty about whether you should just get on to the definitive procedure if you get a positive on either test rather than mucking around more.
Save the stress ECHO spots for those at more risk from radiation.High Risk
You shouldn't even be here! If the patient has a positive Troponin or ECG changes or the whole thing just screams crescendo angina then they should be getting admitted for an angiogram.
