title: Evaluation of coronary microvascular function in patients with vasospastic angina.
abstract: OBJECTIVE
  To investigate endothelium-dependent and -independent coronary microvascular functions in patients with vasospastic angina (VSA).
  
  
  METHODS
  Thirty-six patients with VSA (30 men and 6 women; mean age, 58 years) were enrolled in this study. VSA was defined as ≥ 90% narrowing of the epicardial coronary arteries on angiography performed during a spasm provocation test, presence of chest pain, and/or ST-segment deviation on an electrocardiogram (ECG). Patients (n = 36) with negative spasm provocation test results and those matched for age and sex were enrolled as a control group (nonVSA group). Low-dose acetylcholine (ACh; 3 μg/min) was infused into the left coronary ostium for 2 min during the spasm provocation test. Following the spasm provocation test, nitroglycerin (0.2 mg) was administered intracoronally. Coronary blood flow (was calculated from quantitative angiography and Doppler flow velocity measurements, and the coronary flow reserve was calculated as the ratio of coronary flow velocity after injection of adenosine triphosphate (20 μg) to the baseline value. Changes in the coronary artery diameter in response to ACh and nitroglycerin infusion were expressed as percentage changes from baseline measurements.
  
  
  RESULTS
  Body mass index was significantly lower in the VSA group than in the nonVSA group. The frequency of conventional coronary risk factors and the rate of statin use were similar between the 2 groups. The left ventricular ejection fraction as evaluated by echocardiography was similar between the 2 groups. The duration of angina was 9 ± 2 mo. The results of blood chemistry analysis were similar between the 2 groups. Low-dose ACh did not cause coronary spasms. The change in coronary artery diameter in response to ACh was lower in the VSA group (-1.4% ± 9.3%) than in the nonVSA group (3.1% ± 6.5%, P < 0.05), whereas nitroglycerin-induced coronary artery dilatation and coronary blood flow increase in response to ACh or coronary flow reserve did not differ significantly between the 2 groups.
  
  
  CONCLUSIONS
  These findings suggest that microvascular coronary function may be preserved despite endothelial dysfunction of the epicardial coronary arteries in patients with VSA.
authors: Hiroki Teragawa, Department of Cardiovascular Medicine, Hiroshima General Hospital of West Japan Railway Company, Hiroshima 732-0057, Japan.
authors: Hiroki
authors: H
authors: Teragawa
authors: Naoya
authors: N
authors: Mitsuba
authors: Ken
authors: K
authors: Ishibashi
authors: Kenji
authors: K
authors: Nishioka
authors: Satoshi
authors: S
authors: Kurisu
authors: Yasuki
authors: Y
authors: Kihara
keywords: Acetylcholine; Coronary spasm; Endothelial function
references: J Cardiol. 2000 Jul;36(1):17-27
references: 10929262
references: J Cardiovasc Pharmacol. 1993;22 Suppl 4:S1-14
references: 7523767
references: Circ J. 2002 Jan;66(1):58-62
references: 11999667
references: J Cardiol. 2008 Feb;51(1):2-17
references: 18522770
references: Clin Chem. 1972 Jun;18(6):499-502
references: 4337382
references: Circ J. 2010 Aug;74(8):1745-62
references: 20671373
references: Cardiovasc Res. 1999 Sep;43(4):1029-39
references: 10615430
references: Clin Cardiol. 2003 Aug;26(8):377-83
references: 12918640
references: Eur Heart J. 2013 Jan;34(4):258-67
references: 22782943
references: Lancet. 1989 Oct 28;2(8670):997-1000
references: 2572793
references: Coron Artery Dis. 2003 Sep;14(6):423-9
references: 12966262
references: Circulation. 1988 Mar;77(3):535-42
references: 3342484
references: Clin Cardiol. 2005 Oct;28(10):460-6
references: 16274093
references: Am J Cardiol. 1997 Sep 15;80(6):705-10
references: 9315573
references: Am J Cardiol. 2003 Dec 15;92(12):1394-8
references: 14675572
references: Circulation. 1986 Nov;74(5):955-63
references: 3769179
references: Heart. 2004 Jul;90(7):750-4
references: 15201242
references: Circulation. 2002 Apr 2;105(13):1545-7
references: 11927519
references: J Am Coll Cardiol. 1996 Feb;27(2):304-10
references: 8557898
references: World J Cardiol. 2010 Jul 26;2(7):205-10
references: 21160752
references: World J Cardiol. 2010 Feb 26;2(2):34-42
references: 21160682
references: Am Heart J. 1996 Jun;131(6):1051-7
references: 8644581
references: Nature. 1980 Nov 27;288(5789):373-6
references: 6253831
references: Am J Cardiol. 2007 Sep 15;100(6):962-4
references: 17826378
references: J Clin Invest. 1992 Mar;89(3):1047-52
references: 1371774
references: Hypertension. 1989 Jun;13(6 Pt 2):658-67
references: 2661425
references: Heart. 1997 Nov;78(5):493-8
references: 9415011
references: J Am Coll Cardiol. 1997 Oct;30(4):920-6
references: 9316519
references: J Am Coll Cardiol. 1992 Jun;19(7):1426-34
references: 1593035
references: Heart. 2001 Aug;86(2):212-6
references: 11454846
references: Coron Artery Dis. 2003 Sep;14(6):451-7
references: 12966266
references: Cardiovasc Res. 2002 Feb 15;53(3):620-6
references: 11861032
references: Intern Med. 1997 Nov;36(11):760-5
references: 9392345