Assessment of coronary vasomotor responses to acetylcholine in German and Japanese patients with epicardial coronary spasm-more similarities than differences?

Coronary spasm is an established cause for angina pectoris. Ethnic differences have been suggested among Asian compared to Caucasian patients regarding prevalence, gender distribution, and angiographic patterns of coronary spasm. The aim of this study was to compare contemporary German and Japanese patients with coronary spasm. Between 2011 and 2015, 149 patients with resting angina and unobstructed coronary arteries with acetylcholine-induced epicardial spasm were enrolled in Stuttgart, Germany (n = 69) and Sendai, Japan (n = 80). All patients underwent intracoronary acetylcholine testing according to a standardized protocol. Comprehensive analysis included type of spasm (focal/diffuse), dose of acetylcholine leading to spasm, and frequency of multivessel spasm. Patients in this study were 61 ± 11 years old, predominantly female (54%), and had normal left ventricular ejection fraction (73 ± 9%). Diffuse spasm was the most prevalent type of spasm (85%) whereas focal spasm was found in the remaining 15% of patients. 31% of patients had multivessel spasm. Comparing the German with the Japanese patients, distribution of spasm type (focal/diffuse, p = 0.19) and frequency of multivessel spasm (p = 0.22) were comparable. Moreover, when Japanese patients were compared with German patients and diffuse spasm with focal spasm patients, respectively, no significant differences were observed regarding the acetylcholine dose required to induce spasm (p = 0.078 and p = 0.46, respectively). In conclusion, diffuse epicardial coronary spasm is the most frequent finding among German and Japanese patients with resting angina, unobstructed coronary arteries, and epicardial spasm on acetylcholine testing. Japanese and German patients share several similarities including comparable types of spasm and frequency of multivessel spasm.

In vivo assessment of ergonovine-induced coronary artery spasm by 64-slice multislice computed tomography.

BACKGROUND: The potential of multislice CT (MSCT) to predict coronary spasm has not been elucidated. The aim of this study was to investigate whether the morphological features observed on MSCT at the site of ergonovine-induced epicardial spasm could be used as diagnostic criteria for coronary spasm. METHODS AND RESULTS: A total of 296 plaques in 199 patients with clinically suspected coronary spastic angina without coronary stenosis (<75%) who underwent invasive angiography with intravenous ergonovine provocative testing were analyzed by MSCT. Calcification, CT attenuation, and patterns of vascular remodeling were evaluated in each plaque by MSCT. Plaques were divided into spasm group or nonspasm group based on the results of the ergonovine provocative test. On a per-plaque basis, noncalcified plaques were more frequently observed in the spasm group (96% versus 20%, P<0.01). Intermediate attenuation plaques (CT density ≥53.8 Hounsfield units identified by receiver operating characteristic analysis) were more common in the spasm group (93% versus 28%, P<0.01), as was negative remodeling (67% versus 11%, P<0.01). Multivariable analysis revealed noncalcified (odds ratio [OR], 48.7; 95% CI, 8.81-269; P<0.01), intermediate attenuation (OR, 19.3; 95% CI, 4.96-75.4; P<0.01); negative remodeling (OR, 8.83; 95% CI, 2.87-27.2; P<0.01); and male sex (OR, 4.55; 95% CI, 1.24-16.6; P=0.02) as predictors of the plaque associated with coronary spasm. CONCLUSIONS: MSCT can detect differences in individual plaque composition and morphology among atherosclerotic plaques without significant luminal narrowing in areas of inducible vasospasm compared to areas without vasospasm.

Pharmacological assessment of composite arterial conduits using angiography early in the postoperative period.

OBJECTIVES: Muscular arteries are vulnerable to vasospasm unlike elastic arteries. Having developed experimental models of composite arterial grafts, we assessed and compared the responses of the grafts with different pharmacological agents using angiography early in the postoperative period. SUBJECTS AND METHODS: We harvested the internal thoracic artery (ITA) and brachial-median artery (BMA) from 10 sheep. BMA was used as an alternative to the radial artery. Each vessel was assessed histologically and morphologically. Then, a serial composite graft was constructed so that BMA was interposed. On postoperative day one or two, angiography was performed on the composite graft to measure the diameter of each vessel in response to phenylephrine (alpha-adrenergic receptor agonist), nitroglycerin+phenylephrine, and milrinone+phenylephrine. RESULTS: The BMA had a wide media layer which consisted of abundant smooth muscle cells. The combined intima and media were thicker in BMA than in ITA (p<0.01). After injection of phenylephrine, the BMA diameter decreased (2.5+/-0.4 mm to 1.9+/-0.3 mm, p<0.01), while the ITA diameter remained unchanged (3.7+/-0.2 mm to 3.6+/-0.2 mm). Continuous infusion of nitroglycerin or milrinone prevented phenylephrine-induced vasoconstriction of the BMA (p<0.05). CONCLUSIONS: These results suggest that muscular arteries have a more pronounced vasoconstrictive response to alpha-adrenergic receptor agonists than the elastic arteries. To avoid potential decrease in graft flow of muscular artery, it is advisable to use a vasodilator nitroglycerin or milrinone early in the postoperative period.