[Provocation tests for coronary spasm. Methods, value and indications].
Five methods are currently used to demonstrate coronary spasm: they use derivatives of ergotamine, alkalinisation, cold, adenosine triphosphate and exercise stress test. The criteria used to confirm spasm are either direct visualisation at coronary angiography or indirect electrocardiographic changes. The value of these test is beginning to be established: --their specificity is excellent with all methods (a positive test is diagnostic); --their sensitivity is mediocre (a negative test does not exclude the diagnosis). This depends on three factors: the choice of criteria of positivity: angiographic appearances is the most reliable; the timing of the test: it is more likely to be positive when the test is carried out close to episodes of chest pain; the method of provocation: the most sensitive tests use either the ergotamine derivatives or alkalinisation; --reproductibility is satisfactory at short and long term. These tests have diagnostic and therapeutic indications. It is preferable to perform diagnostic tests during coronary angiography in patients with normal coronary arteries and unexplained episodes of chest pain. However, in patients with fixed coronary lesions (except triple vessel and left main stem disease) when coronary bypass surgery is planned, the results of the test can help in the choice of associated therapy, such as plexectomy and calcium antagonist drugs. The repetition of the test is useful in the evaluation of antispastic therapy: when the test becomes negative the drug used is probably effective. In conclusion, with equal patient comfort and MSR, provocation tests using the ergotamine derivatives would seem to be the method of choice: alkalinisation is a good alternative.
D000255:Adenosine Triphosphate; D003080:Cold Temperature; D003329:Coronary Vasospasm / Q000175:diagnosis* / Q000000981:diagnostic imaging; D004562:Electrocardiography; D004879:Ergotamines; D005080:Exercise Test; D006801:Humans; D011859:Radiography
D004879:Ergotamines; D000255:Adenosine Triphosphate
Les tests de provocation du spasme coronarien. Méthodes, valeur et indications.