Marwick T H, D'Hondt A M, Mairesse G H, Baudhuin T, Wijns W, Detry J M, Melin J A
Division of Cardiology, Clinique Universitaires St Luc, University of Louvain, Brussels, Belgium.
Br Heart J. 1994 Jul;72(1):31-8. doi: 10.1136/hrt.72.1.31.
To compare the ability of dobutamine and exercise stress to induce myocardial ischaemia and perfusion heterogeneity under routine clinical circumstances.
86 active patients without previous myocardial infarction were studied by dobutamine and exercise stress protocols and coronary angiography. During both tests patients underwent electrocardiography, digitised echocardiography, and perfusion scintigraphy using Tc-99m methoxybutylisonitrile (MIBI) single photon emission computed tomography.
Coronary disease defined as an ST segment depression of > or = 0.1 mV, a resting or stress induced perfusion defect, or a resting or stress induced wall motion abnormality on exercise and dobutamine stress testing.
Dobutamine stress was submaximal in 51 patients because of ingestion of beta adrenoceptor blocking agents on the day of the test (n = 25) or failure to attain the peak dose owing to side effects (n = 28). Exercise was limited in 23 patients by non-cardiac symptoms. The peak heart rate with dobutamine was less than that attained with exercise (105 (25) v 132 (24) beats/min, P < 0.0001); the response to maximal dobutamine stress significantly exceeded that to submaximal stress. Peak blood pressure was greatest with exercise (206 (27) v 173 (25) mm Hg, P < 0.001), values at maximal and submaximal dobutamine stress being comparable. Electrocardiographic evidence of ischaemia was induced less frequently by dobutamine than exercise (32% v 77% of the 56 patients with significant coronary disease, P < 0.01), as was abnormal wall motion (54% v 88%, P < 0.001). Ischaemia was induced more readily with maximal stress of either type; thus the sensitivities of dobutamine and exercise echocardiography were comparable only in patients undergoing a maximal dobutamine testing (73% v 77%, NS). Perfusion heterogeneity was induced in 58% of patients with coronary disease at submaximal dobutamine stress, 73% at maximal dobutamine stress, and 73% at exercise stress (NS). Among 30 patients without coronary stenoses, normal function was obtained in 83% of echocardiography studies with dobutamine and in 80% with exercise (NS). Normal perfusion was identified in 70% of these patients at exercise MIBI, and 68% at dobutamine stress (NS).
In a group of patients studied under normal clinical circumstances antianginal treatment and inability to complete the stress protocol are frequent and compromise the capacity of dobutamine stress to induce ischaemia. In contrast, the induction of perfusion heterogeneity is less susceptible to submaximal stress.
比较在常规临床情况下多巴酚丁胺和运动负荷诱发心肌缺血及灌注不均一性的能力。
对86例无既往心肌梗死的活动患者采用多巴酚丁胺和运动负荷方案及冠状动脉造影进行研究。在两项检查过程中，患者均接受心电图、数字化超声心动图检查，并使用锝-99m甲氧基异丁基异腈（MIBI）单光子发射计算机断层扫描进行灌注闪烁显像。
冠状动脉疾病定义为在运动和多巴酚丁胺负荷试验中ST段压低≥0.1 mV、静息或负荷诱发的灌注缺损，或静息或负荷诱发的室壁运动异常。
51例患者的多巴酚丁胺负荷试验未达最大剂量，原因是试验当天服用了β肾上腺素能阻滞剂（n = 25）或因副作用未能达到峰值剂量（n = 28）。23例患者因非心脏症状而运动受限。多巴酚丁胺负荷试验时的最高心率低于运动负荷试验时的最高心率（105（25）次/分钟对132（24）次/分钟，P < 0.0001）；对最大多巴酚丁胺负荷试验的反应明显超过对次最大负荷试验的反应。运动时的最高血压最高（206（27）mmHg对173（25）mmHg，P < 0.001），最大和次最大多巴酚丁胺负荷试验时的血压值相当。多巴酚丁胺诱发缺血性心电图证据的频率低于运动负荷试验（在56例有显著冠状动脉疾病的患者中分别为32%对77%，P < 0.01），室壁运动异常的情况也是如此（54%对88%，P < 0.001）。两种类型的最大负荷试验更容易诱发缺血；因此，多巴酚丁胺和运动超声心动图的敏感性仅在接受最大多巴酚丁胺试验的患者中相当（73%对77%，无显著性差异）。次最大多巴酚丁胺负荷试验时，58%的冠状动脉疾病患者出现灌注不均一性，最大多巴酚丁胺负荷试验时为73%，运动负荷试验时为73%（无显著性差异）。在30例无冠状动脉狭窄的患者中，83%的多巴酚丁胺超声心动图检查和80%的运动超声心动图检查结果正常（无显著性差异）。在这些患者中，运动MIBI检查时70%的患者灌注正常，多巴酚丁胺负荷试验时68%的患者灌注正常（无显著性差异）。
在一组正常临床情况下研究的患者中，抗心绞痛治疗和无法完成负荷试验的情况很常见，这会影响多巴酚丁胺负荷试验诱发缺血的能力。相比之下，次最大负荷试验对灌注不均一性诱发的影响较小。
