Rott D, Lawson W E, Lillis O, Dervan J P
George Hyman Research Building, Room 117, 108 Irving Street, N.W., Washington, D.C., 20010, USA.
J Invasive Cardiol. 2000 Mar;12(3):130-3.
Coronary artery reference diameters increase during coronary angioplasty (PTCA). However, in clinical practice, balloon selection is often based on a preceding diagnostic coronary angiogram. It is common to find that the initially selected balloon is undersized due to resting vasomotor tone. This may contribute to a suboptimal angioplasty result.
Quantitative coronary angiography (QCA) was used to determine the magnitude of coronary artery vasodilatation over baseline angiography and its impact on balloon size choice. Pre-PTCA clinical and treatment variables were analyzed for their potential contribution to resting vasomotor tone.
QCA of reference coronary diameters was performed in a group of 103 patients undergoing PTCA. Post PTCA proximal and distal reference diameters significantly increased over baseline. The average increase of the proximal segment was 0.368 mm (13.6%) p < 0. 001 and of the distal segment 0.567 mm (24.8%) p < 0.001. The initial nominal balloon diameter was smaller than the post PTCA proximal segment by an average of 0.34 mm (12.6%) p < 0.001. Of the clinical and treatment variables examined age < 65 years and pre-PTCA beta blocker use, significantly affected baseline vasomotor tone p < 0.05.
Routine diagnostic angiography underestimates the true diameter of the coronary artery. Due to baseline vasomotor tone, coronary reference segments can be expected to increase approximately 13% in diameter during successful PTCA. Patients under 65 years of age and those using beta-blockers may have a significantly increased baseline vasomotor tone. Underestimation of coronary artery diameter based on initial angiography necessitated a second, larger balloon in 16.5% of cases.
冠状动脉血管成形术（PTCA）期间冠状动脉参考直径会增加。然而，在临床实践中，球囊的选择通常基于先前的诊断性冠状动脉造影。由于静息血管舒缩张力，常发现最初选择的球囊尺寸过小。这可能导致血管成形术效果欠佳。
采用定量冠状动脉造影（QCA）来确定冠状动脉相对于基线造影的扩张程度及其对球囊尺寸选择的影响。分析PTCA术前的临床和治疗变量对静息血管舒缩张力的潜在影响。
对103例行PTCA的患者进行了冠状动脉参考直径的QCA检查。PTCA术后近端和远端参考直径较基线显著增加。近端节段平均增加0.368 mm（13.6%），p < 0.001；远端节段平均增加0.567 mm（24.8%），p < 0.001。初始标称球囊直径比PTCA术后近端节段平均小0.34 mm（12.6%），p < 0.001。在所检查的临床和治疗变量中，年龄<65岁以及PTCA术前使用β受体阻滞剂，对基线血管舒缩张力有显著影响，p < 0.05。
常规诊断性血管造影会低估冠状动脉的真实直径。由于基线血管舒缩张力，在成功的PTCA期间，冠状动脉参考节段直径预计会增加约13%。65岁以下的患者以及使用β受体阻滞剂的患者基线血管舒缩张力可能会显著增加。基于初始血管造影对冠状动脉直径的低估使得16.5%的病例需要使用第二个更大的球囊。
