New combined spasm provocation test in patients with rest angina - Intracoronary injection of acetylcholine after intracoronary administration of ergonovine

The incidence of provoked coronary spasm with the standard single spasm pro vocation test has been relatively low in patients with rest angina. The pre sent study examined the clinical usefulness of a newly designed spasm provo cation test, an intracoronary injection of acetylcholine (ACh) following an ergonovine (ER) test, in patients with rest angina who demonstrated low di sease activity and atypical chest pain. Triple sequential spasm provocation tests were performed in 24 patients with atypical chest pain who had no is chemia and in 40 patients with rest angina who had distinct ischemia. Initi ally, an ACh test (20-100 mu g) and then an ER test (40-64 mu g) were perfo rmed and then, if no spasm was provoked, an intracoronary injection of ACh was given after the ER test to evaluate coronary spasm. Coronary spasm was defined as total or subtotal occlusion. In the 24 patients with atypical ch est pain, no spasm was provoked by intracoronary injection of either ACh or ER, but coronary spasms were induced in 2 patients using the new method, w ith the remaining 22 not experiencing spasm (specificity of new method, 92% ). In the 40 patients with rest angina, intracoronary injection of ACh indu ced coronary spasm in 22 patients (group I) and 6 (group II) demonstrated s pasm with intracoronary injection of ER. Coronary spasm was not induced by either the ACh test or the ER test in 12 patients (group III). The intracor onary administration of ACh after the ER test provoked spasm in 11 of 12 pa tients. Diffuse spasms were provoked in 10 of 11 patients. In patients with rest angina, the frequency of chest pain attacks in 1 month experienced by patients in group III (0.8+/-0.8) was significantly lower than that of pat ients in group I (7.0+/-5.3, p<0.01) or II (3.5+/-2.3, p<0.05). No serious or irreversible complications related to this new combined method were obse rved. In conclusion, this method was safe and reliable fur the induction of coronary spasm in patients with rest angina who may have low disease activ ity.