Andersen Mads P, Terkelsen Christian J, Sørensen Jacob T, Kaltoft Anne K, Nielsen Søren S, Struijk Johannes J, Bøtker Hans E
Department of Health Science and Technology, Aalborg University, Aalborg, Denmark.
J Electrocardiol. 2010 Mar-Apr;43(2):121-31. doi: 10.1016/j.jelectrocard.2009.12.001.
Analysis of ST deviations from the 12-lead electrocardiogram allows for estimation of a spatial ST injury vector. The goal of the present study was to compare the location and extent of transmural myocardial ischemia evaluated by myocardial perfusion imaging with the direction and magnitude of the ST injury vector.
Twelve-lead electrocardiograms were recorded from 75 acute myocardial infarction patients with single-vessel disease and thrombolysis in myocardial infarction (TIMI) flow 0/1 (30 left anterior descending [LAD], 28 right coronary artery [RCA], 17 left circumflex artery [LCX]). ST deviations were measured in the J point in all leads and used to estimate ST injury vectors for each patient. Myocardial perfusion imaging was performed to evaluate the extent and location of myocardial ischemia at the time of coronary intervention.
Ninety-two percent of the patients showed ST injury vectors within the expected directional range for the identified anatomic segment of ischemia by myocardial perfusion imaging. ST injury vector direction separated LAD, RCA, and LCX occlusion patients; 90% of the LAD patients showed anterior vectors, 82% of the RCA patients showed posteroinferoseptal vectors, and 59% of the LCX patients showed posteroinferolateral vectors. Eight patients did not fulfill the ST elevation criteria for ST elevation myocardial infarction but showed anterior ST depression and prominent ST injury vectors in the posterior torso direction. There was a moderate correlation between the extent of ischemia and ST injury vector magnitude for the ischemic patients, r = 0.29.
We found strong agreement between the direction of the ST injury vector and the location of myocardial ischemia. The ST injury vector may be the key to higher diagnostic accuracy for inferobasal transmural ischemia and may help distinguishing between RCA and LCX occlusions in the acute phase.
分析12导联心电图的ST段偏移可估计空间ST段损伤向量。本研究的目的是比较心肌灌注成像评估的透壁心肌缺血的位置和范围与ST段损伤向量的方向和大小。
记录了75例单支血管病变且心肌梗死溶栓（TIMI）血流为0/1的急性心肌梗死患者的12导联心电图（30例左前降支[LAD]、28例右冠状动脉[RCA]、17例左旋支[LCX]）。测量所有导联J点处的ST段偏移，并用于估计每位患者的ST段损伤向量。在冠状动脉介入时进行心肌灌注成像以评估心肌缺血的范围和位置。
92%的患者的ST段损伤向量在心肌灌注成像确定的缺血解剖节段的预期方向范围内。ST段损伤向量方向可区分LAD、RCA和LCX闭塞患者；90%的LAD患者表现为前向向量，82%的RCA患者表现为后下间隔向量，59%的LCX患者表现为后下外侧向量。8例患者不符合ST段抬高型心肌梗死的ST段抬高标准，但表现为前壁ST段压低和后躯干方向明显的ST段损伤向量。缺血患者的缺血范围与ST段损伤向量大小之间存在中度相关性，r = 0.29。
我们发现ST段损伤向量的方向与心肌缺血的位置之间有很强的一致性。ST段损伤向量可能是提高下基底透壁缺血诊断准确性的关键，并且可能有助于在急性期区分RCA和LCX闭塞。
