Ultra-long acting calcium channel blockers may decrease accuracy of the acetylcholine provocation test

• Published in: International journal of cardiology 2017-06, Vol.236, p.71-75
• Main Authors: Kurabayashi, Manabu, Asano, Mitsutoshi, Shimura, Tsukasa, Suzuki, Hidetoshi, Aoyagi, Hideshi, Yamauchi, Yasuteru, Okishige, Kaoru, Ashikaga, Takashi, Isobe, Mitsuaki
• Format: Article
• Language: English
• Subjects: Acetylcholine - administration & dosage; Acetylcholine provocation test; Aged; Angina Pectoris, Variant - diagnosis; Angina Pectoris, Variant - drug therapy; Calcium channel blocker; Calcium Channel Blockers - administration & dosage; Calcium Channel Blockers - classification; Calcium Channel Blockers - pharmacokinetics; Cardiovascular; Coronary Angiography - methods; Coronary artery spasm; Coronary artery tone; Coronary Vasospasm - chemically induced; Coronary Vasospasm - physiopathology; Coronary Vessels - diagnostic imaging; Coronary Vessels - drug effects; Coronary Vessels - physiopathology; Dimensional Measurement Accuracy; Female; Half-Life; Humans; Male; Middle Aged; Outcome Assessment (Health Care); Vasodilator Agents - administration & dosage; Withholding Treatment - standards
• ISSN: 0167-5273; 1874-1754
• DOI: 10.1016/j.ijcard.2017.02.123

Abstract Background When drug-induced coronary spasm provocation tests are performed, a washout period of > 48 h for calcium channel blockers (CCBs) is uniformly recommended. However, each CCB has a distinct half-life, and little is known about the influence of prior oral administration of CCBs on acetylcholine provocation test to evaluate coronary vasomotor reaction. Methods and results We examined 245 consecutive patients with suspected vasospastic angina who had undergone acetylcholine provocation test. Of those patients, 29 patients had been on amlodipine, an ultra-long term acting CCB (group A), 34 on other CCBs (group O), and 182 patients on no CCB (group N). After CCBs had been withheld > 48 h, we performed acetylcholine provocation, which resulted in 152 positive, 36 intermediate, and 57 negative reactions. We evaluated coronary artery tone calculated as follows: (luminal diameter after nitrate − baseline luminal diameter) ÷ (luminal diameter after nitrate) × 100 (%). In group A patients, coronary artery tone was lower (A:9.1 ± 6.9% vs. O:11.7 ± 8.3% vs. N:12.1 ± 8.5%, p = 0.0011) and the positive rate of acetylcholine provocation test was lower than group O and group N (A:41% vs. O:68% vs. N:64%, p = 0.047). Multivariate logistic analysis showed that taking amlodipine until 2 days before acetylcholine provocation test was a significant inverse predictor for acetylcholine-provoked coronary spasm (odds ratio 0.327; 95% confidence interval 0.125–0.858, p = 0.023). Conclusions Residual vasodilatory effects of ultra-long acting CCB may decrease coronary artery tone and the vasoconstrictive reaction to acetylcholine suggesting that a 2-day pre-test drug holiday may not be long enough.