Coronary flow limitation during the development of ischemia. Effect of atrial pacing in patients with left anterior descending coronary artery disease.
Coronary flow limitation during the development of ischemia. Effect of atrial pacing in patients with left anterior descending coronary artery disease.
复制标题
缺血发生期间冠状动脉血流受限。
DOI：
10.1016/0002-9149(81)90316-7
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发表时间：
1981
期刊：
影响因子：
--
通讯作者：
Yin,FC
中科院分区：
文献类型：
--
作者：
Fuchs,RM;Brinker,JA;Maughan,WL;Weisfeldt,ML;Yin,FC
心房起搏性心动过速引起心肌需氧量增加，在冠状动脉明显狭窄的患者中，当冠状动脉增加血流的能力有限时，可导致心绞痛的发展。本研究评估了单冠状动脉床因需氧量逐渐增加而缺血时冠状动脉血流的反应。在20例患者中，通过增量心房起搏增加心率，直到达到最大心率或心绞痛发生时，获得了心脏大静脉流量的热稀释测量，代表了左冠状动脉前降支区域的流出量。20例患者中有10例在血管造影中没有明显的冠状动脉狭窄，10例病变阻塞了超过50%的左冠状动脉前降支直径，但没有其他明显的冠状动脉狭窄。两组在静息心率、主动脉压、左室舒张末压、心大静脉流量方面无显著差异。在整个起搏试验中，随着心率的每一次增加，无明显冠状动脉狭窄的患者心脏大静脉血流稳定增加。在所有次最大起搏增量期间，有和没有明显狭窄的患者每增加一次心率的心大静脉流量的增加是相似的（平均值±标准差分别为1.05±0.48 ml/次和0.79±0.31 ml/次）。然而，在最终起搏增量中，冠状动脉狭窄患者的心大静脉流量没有增加，而无疾病患者的心大静脉流量继续增加（Δ= 0.10±0.19 ml/次vs . 1.3±0.69 ml/次，p < 0.001）。10例冠状动脉狭窄患者均出现这种血流受限现象，且均伴有心绞痛或S-T段改变，或两者兼有。冠状动脉左前降支病变患者与非左前降支病变患者冠状动脉血流模式的显著差异可能有助于(1)进一步研究人类心肌缺血的病理生理学和治疗，以及(2)对特定患者冠状动脉左前降支病变血流动力学重要性的临床评估。
Atrial pacing-induced tachycardia causes increased myocardial oxygen demand and leads to the development of angina in patients with significant coronary arterial narrowing, when the ability to augment coronary flow is limited. This study evaluated the response of coronary flow in a single coronary bed as that bed was rendered ischemic by progressive increases in oxygen demand. Thermodilution measurements of great cardiac vein flow, representing the efflux from the territory of the left anterior descending coronary artery, were obtained in 20 patients as heart rate was increased by incremental atrial pacing until the maximal heart rate was reached or angina developed. Ten of the 20 patients had no significant coronary narrowing on angiography, and 10 had a lesion obstructing more than 50 percent of the diameter of the left anterior descending coronary artery but no other significant coronary narrowing. No significant difference was found between the two groups in resting heart rate, aortic pressure, left ventricular end-diastolic pressure or great cardiac vein flow. With each increment in heart rate throughout the pacing test, the patients without significant coronary stenosis showed a steady increase in great cardiac vein flow. During all submaximal pacing increments, the increase in great cardiac vein flow per increment in heart rate was similar in those with and without significant stenosis (mean ± standard deviation 1.05 ± 0.48 ml/beat versus 0.79 ± 0.31 ml/beat, respectively). However, over the final pacing increment, the patients with coronary stenosis had no increase in great cardiac vein flow, whereas those without disease continued to have increased flow (Δ= 0.10 ± 0.19 ml/beat versus 1.3 ± 0.69 ml/beat, respectively, p < 0.001). This flow limitation phenomenon was observed in all 10 patients with coronary stenosis and was accompanied by angina or S-T segment changes, or both, in all 10. This striking difference in coronary flow patterns between patients with and without significant left anterior descending coronary artery disease may prove useful in (1) further studies of the pathophysiology and therapy of myocardial ischemia in human beings, and (2) clinical evaluation of the hemodynamic importance of left anterior descending coronary arterial lesions in selected patients.