Shapira O M, Xu A, Vita J A, Aldea G S, Shah N, Shemin R J, Keaney J F
Department of Cardiothoracic Surgery and Evans Department of Medicine, Boston University School of Medicine, Boston, MA, USA.
J Thorac Cardiovasc Surg. 1999 May;117(5):906-11. doi: 10.1016/S0022-5223(99)70370-3.
Recent reports of improved radial artery patency have been attributed, in part, to routine use of diltiazem to prevent vasospasm. However, diltiazem is costly, and its use may be associated with negative inotropic and chronotropic side effects. This study compares the vasodilatory properties of diltiazem to those of nitroglycerin.
In vitro, with the use of organ chambers, the vasodilatory properties of diltiazem and nitroglycerin were compared in matched segments of radial artery, internal thoracic artery, and saphenous vein that were harvested from the same patients (n = 11). The vasodilatory response of the radial artery to intravenous diltiazem or nitroglycerin was compared in vivo (n = 10) with the use of ultrasonographic measurements of radial artery diameter.
The maximum relaxation of radial artery (100% +/- 4%), internal thoracic artery (96% +/- 4%), and saphenous vein (100% +/- 3%) to nitroglycerin were significantly greater than the response to diltiazem (33% +/- 6%, 22% +/- 7%, and 34% +/- 5%, respectively; P <.001). The thromboxane mimetic, U46619, induced radial artery spasm with a median effective concentration of 3.7 +/- 0.8 nmol/L. Physiologic concentrations of nitroglycerin (0.1+/- micromol/L) significantly inhibited the radial artery response to U46619 (median effective concentration, 6.2 +/- 1.1 nmol/L; P =.046), whereas diltiazem (1 micromol/L) did not (median effective concentration, 3.7 +/- 0.8 nmol/L; P =.64). In vivo, nitroglycerin increased radial artery diameter 22% +/- 3%, which was significantly greater than diltiazem (3% +/- 0.5%; P =.001).
Nitroglycerin is a superior conduit vasodilator and is more effective in preventing graft spasm than diltiazem. Nitroglycerin should be strongly considered as the drug of choice to prevent conduit spasm after coronary bypass grafting.
近期有关桡动脉通畅率提高的报道部分归因于常规使用地尔硫䓬预防血管痉挛。然而，地尔硫䓬成本高昂，且其使用可能与负性肌力和变时性副作用相关。本研究比较了地尔硫䓬与硝酸甘油的血管舒张特性。
在体外，使用器官腔室，比较了从同一患者（n = 11）获取的桡动脉、胸廓内动脉和大隐静脉匹配节段中地尔硫䓬和硝酸甘油的血管舒张特性。在体内（n = 10），通过超声测量桡动脉直径，比较了桡动脉对静脉注射地尔硫䓬或硝酸甘油的血管舒张反应。
桡动脉（100% ± 4%）、胸廓内动脉（96% ± 4%）和大隐静脉（100% ± 3%）对硝酸甘油的最大舒张幅度显著大于对地尔硫䓬的反应（分别为33% ± 6%、22% ± 7%和34% ± 5%；P <.001）。血栓素类似物U46619诱导桡动脉痉挛，中位有效浓度为3.7 ± 0.8 nmol/L。生理浓度的硝酸甘油（0.1 ± μmol/L）显著抑制桡动脉对U46619的反应（中位有效浓度，6.2 ± 1.1 nmol/L；P =.046），而地尔硫䓬（1 μmol/L）则无此作用（中位有效浓度，3.7 ± 0.8 nmol/L；P =.64）。在体内，硝酸甘油使桡动脉直径增加22% ± 3%，显著大于地尔硫䓬（3% ± 0.5%；P =.001）。
硝酸甘油是一种更优的血管桥血管舒张剂，在预防移植血管痉挛方面比地尔硫䓬更有效。硝酸甘油应被强烈视为冠状动脉旁路移植术后预防血管桥血管痉挛的首选药物。
