Oliveira M, Galrinho A, Rosário L, Cacela D, Ferreira R, Ferreira M, Roquette J, Quininha J, Bento R, Antunes A M
Internato Complementar de Cardiologia, Hospital de Santa Marta, Lisboa.
Rev Port Cardiol. 1996 Sep;15(9):633-8, 611-2.
Although treadmill exercise testing (TET) has been used to identify ischaemia and determine clinical prognosis after myocardial revascularization, considerable controversy remains on its role in the detection of obstructive lesions of the arterial grafts.
To assess the value of TET in determining the patency of arterial conduits after coronary bypass surgery with complete revascularization.
Twenty five patients - 21 men and 4 women; age 53.7 +/- 8.7 years - submitted to complete myocardial revascularization exclusively with arterial conduits (CABG-A), undergoing coronary angiography and a symptomlimited TET (Bruce protocol) within 9 months after CABG-A. Angiograms were visually classified in 2 groups (Group I - conduits without lesions, n = 14; Group II > 50% stenosis or occlusion of > or = 1 conduit, n = 11). Clinical characteristics and the following parameters of the TET were compared: total exercise time (ETime); metabolic equivalents (METS); % of predicted maximal heart rate (% MHR); exercise-induced ST depression (decreases ST); and occurrence of angina. The arterial conduits used were: left internal mammary artery -24-; right internal mammary artery -11-; gastroepiploic artery -14-.
There were no differences in age, gender, left ventricular systolic function, severity of coronary artery disease, and number of conduits per patient. Group I attained superior values for the following parameters: ETime (p < 0.01) and METS (p < 0.01). Among Group II there were more patients with angina (p = 0.03). Fourteen patients exceeded 8 METS (11 from Group I and 3 from Group II - p = 0.002-). There was no statistical difference among the number of patients with ST depression during exercise.
After CABG-A the exercise tolerance seems to be related with the patency of the conduits and may play an important role in the detection of graft abnormalies. On the contrary, exercise-induced ST depression had low specificity in detecting obstructive lesions of the conduits.
尽管跑步机运动试验（TET）已被用于识别心肌血运重建术后的缺血情况并确定临床预后，但其在检测动脉移植物阻塞性病变中的作用仍存在相当大的争议。
评估TET在确定完全血运重建的冠状动脉搭桥术后动脉导管通畅性方面的价值。
25例患者——21例男性和4例女性；年龄53.7±8.7岁——仅接受动脉导管完全心肌血运重建（CABG - A），在CABG - A术后9个月内接受冠状动脉造影和症状限制性TET（布鲁斯方案）。血管造影图像在视觉上分为两组（I组——无病变的导管，n = 14；II组——1条或多条导管狭窄或闭塞>50%，n = 11）。比较临床特征和TET的以下参数：总运动时间（ETime）；代谢当量（METS）；预测最大心率百分比（%MHR）；运动诱发的ST段压低（ST段下降）；以及心绞痛的发生情况。使用的动脉导管有：左内乳动脉——24条；右内乳动脉——11条；胃网膜动脉——14条。
在年龄、性别、左心室收缩功能、冠状动脉疾病严重程度以及每位患者的导管数量方面没有差异。I组在以下参数上达到更高值：ETime（p < 0.01）和METS（p < 0.01）。II组中有心绞痛的患者更多（p = 0.03）。14例患者的代谢当量超过8（I组11例，II组3例——p = 0.002）。运动期间出现ST段压低的患者数量之间没有统计学差异。
CABG - A术后运动耐量似乎与导管通畅性有关，并且可能在检测移植物异常方面发挥重要作用。相反，运动诱发的ST段压低在检测导管阻塞性病变方面特异性较低。
