Mizushige K, Matsuo H, Nozaki S, Kwan O L, DeMaria A N
Cardiology Division, University of California, San Diego 92103-8411, USA.
Am Heart J. 1996 Jan;131(1):131-7. doi: 10.1016/s0002-8703(96)90061-7.
Although the hemodynamic responses to isotonic and isometric exercise are different, few data exist comparing the response to left ventricular (LV) diastolic filling dynamics with these two forms of exertion. Therefore we performed Doppler examination before and at the end of isotonic and isometric exercise in 20 normal volunteers to define the differential responses of LV filling to these two forms of exertion. Transmitral inflow velocity signals from the apical view and phonocardiography were recorded before and at the termination of treadmill exercise (TRD) to 11 METs and handgrip (HG) 50% maximal for 2 minutes). Mean blood pressure (mBP), heart rate (HR), early diastolic (E) and late atrial (A) inflow velocities, mean acceleration rate (ACC) of E wave, time velocity integral of inflow (Ti), and isovolumic relaxation time (IRT) from second heart sound to onset mitral inflow were measured. Absolute changes from baseline were significantly different for the two forms of exertion: TRD versus HG: BP = 11 +/- 9 versus 36 +/- 10 mm Hg, HR = 37 +/- 16 versus 16 +/- 9 beats/min, E = 11.6 +/- 11.3 versus -7.0 +/- 9.4 cm/sec, A = 29.9 +/- 14.5 versus 14 +/- 12 cm/sec, ACC = 164 +/- 151 versus -56 +/- 135 cm/sec2, Ti = 1.9 +/- 3.0 versus -1.7 +/- 1.7 cm, and IRT = -12 +/- 9 versus 9 +/- 10 msec, all p < 0.0001 except for A, p < 0.001). Isotonic treadmill exercise resulted in enhanced early diastolic filling manifested by increases in E and ACC and a decreased in IRT. Conversely, isometric handgrip exercise produced evidence of reduced early filling including decreased E and ACC and slightly increased IRT. Thus the response of LV filling dynamics recorded by Doppler differs for isotonic and isometric exertion and likely reflects the variable pressure and flow alterations induced by these two forms of exertion.
尽管等张运动和等长运动的血流动力学反应不同，但比较这两种运动形式对左心室（LV）舒张期充盈动力学反应的数据却很少。因此，我们对20名正常志愿者在等张运动和等长运动前及运动结束时进行了多普勒检查，以确定左心室充盈对这两种运动形式的不同反应。在跑步机运动（TRD）达到11代谢当量（METs）并持续2分钟以及手握力（HG）达到最大力的50%并持续2分钟之前和结束时，从心尖视图记录二尖瓣流入速度信号并进行心音图检查。测量平均血压（mBP）、心率（HR）、舒张早期（E）和心房晚期（A）流入速度、E波的平均加速度（ACC）、流入时间速度积分（Ti）以及从第二心音到二尖瓣流入开始的等容舒张时间（IRT）。两种运动形式与基线相比的绝对变化有显著差异：TRD与HG相比：血压=11±9与36±10mmHg，心率=37±16与16±9次/分钟，E=11.6±11.3与-7.0±9.4cm/秒，A=29.9±14.5与14±12cm/秒，ACC=164±151与-56±135cm/秒²，Ti=1.9±3.0与-1.7±1.7cm，IRT=-12±9与9±10毫秒，除A外所有p<0.0001，A的p<0.001）。等张跑步机运动导致舒张早期充盈增强，表现为E和ACC增加以及IRT减少。相反，等长手握力运动显示早期充盈减少，包括E和ACC降低以及IRT略有增加。因此，通过多普勒记录的左心室充盈动力学反应在等张运动和等长运动中有所不同，这可能反映了这两种运动形式引起的压力和血流变化。
