Lombardi F, Sandrone G, Spinnler M T, Torzillo D, Lavezzaro G C, Brusca A, Malliani A
Medicina Interna II, Istituto Scienze Biomediche, Ospedale L. Sacco, Università Milano, Milan, Italy.
Am J Cardiol. 1996 May 15;77(12):1037-44. doi: 10.1016/s0002-9149(96)00127-0.
The occurrence of an autonomic disturbance early in acute myocardial infarction (AMI) has been reported: signs of sympathetic activation were mainly observed in relation to an anterior localization, whereas signs of vagal overactivity were more frequent in inferior wall AMI. Information is limited in relation to the persistence of these alterations during the early hours of AMI. We studied 33 patients with an AMI within 188 +/- 16 minutes from the onset of symptoms and 1 week after hospital admission. From a 20-minute Holter recording, we computed with autoregressive methodology, time and frequency domain indexes of heart rate variability. At admission, patients with an anterior wall AMI exhibited a smaller RR variance (593 +/- 121 ms2) than did those with an inferior wall AMI (1,122 +/- 191 ms2). In both groups the spectral profile was characterized by a predominant (73 +/- 4 and 61 +/- 4 normalized units) low frequency and by a small (13 +/- 2 and 22 +/- 3 normalized units) high-frequency component, indicating the presence of a sympathetic excitation and of a diminished vagal modulation. Although signs of sympathetic activation were more evident in patients with anterior wall AMI, no evidence of a vagal hyperactivity was observed in patients with inferior wall AMI. In the latter group, we noticed 1 week after the acute event an increase in the low-frequency component, which reached the values observed in patients with anterior wall AMI. Thrombolysis did not affect heart rate variability parameters. Thus, this study suggests the presence of an autonomic disturbance characterized by signs of sympathetic excitation and of a reduced vagal modulation, which was more evident in patients with an anterior localization early after AMI.
急性心肌梗死（AMI）早期自主神经功能紊乱的发生已有报道：交感神经激活的体征主要见于前壁梗死，而迷走神经活动亢进的体征在下壁AMI中更为常见。关于这些改变在AMI早期数小时内的持续情况，相关信息有限。我们研究了33例症状发作后188±16分钟内发生AMI且入院1周后的患者。通过20分钟的动态心电图记录，我们采用自回归方法计算心率变异性的时域和频域指标。入院时，前壁AMI患者的RR间期方差（593±121ms²）低于下壁AMI患者（1122±191ms²）。两组的频谱特征均以低频成分占主导（分别为73±4和61±4标准化单位）和高频成分较小（分别为13±2和22±3标准化单位）为特点，提示存在交感神经兴奋和迷走神经调节减弱。尽管交感神经激活的体征在前壁AMI患者中更明显，但在下壁AMI患者中未观察到迷走神经活动亢进的证据。在后一组中，我们注意到急性事件1周后低频成分增加，达到了前壁AMI患者观察到的值。溶栓治疗未影响心率变异性参数。因此，本研究提示存在以交感神经兴奋体征和迷走神经调节减弱为特征的自主神经功能紊乱，在AMI早期前壁梗死患者中更为明显。
