Kimura A, Toyota E, Lu S, Goto M, Yada T, Chiba Y, Ebata J, Tachibana H, Ogasawara Y, Tsujioka K, Kajiya F
Department of Medical Engineering and Systems Cardiology, Kawasaki Medical School, Okayama, Japan.
J Am Coll Cardiol. 1996 Mar 15;27(4):810-6. doi: 10.1016/0735-1097(95)00561-7.
We sought to evaluate the effect of intraaortic balloon pumping on the phasic blood velocity waveform into myocardium with severe coronary artery stenosis.
In the presence of severe coronary artery stenosis, it is not clear whether intraaortic balloon pumping augments intramyocardial inflow during diastole or changes systolic retrograde blood flow from the myocardium to the extramural coronary arteries.
Using anesthetized open chest dogs (n=7), we introduced severe stenosis in the left main coronary artery to reduce the poststenotic pressure to approximately 60 mm Hg (>90% diameter stenosis). Septal arterial blood flow velocities were measured with a 20-MHz, 80-channel ultrasound pulsed Doppler velocimeter. Left anterior descending arterial flow, aortic pressure and poststenotic distal coronary pressure were measured simultaneously. The diastolic anterograde flow integral and systolic retrograde flow integral were compared in the presence and absence of intraaortic balloon pumping.
Although intraaortic balloon pumping augmented diastolic aortic pressure, this pressure increase was not effectively transmitted through stenosis. Septal arterial diastolic flow velocity was not augmented, and left anterior descending arterial flow was unchanged during intraaortic balloon pumping.
In the presence of severe coronary artery stenosis, intraaortic balloon pumping failed to increase diastolic inflow in the myocardium and did not enhance systolic retrograde flow from the myocardium to the extramural coronary artery. Thus, the major effect of intraaortic balloon pumping on the ischemic heart with severe coronary artery stenosis may be achieved by reducing oxygen demand by systolic unloading.
我们旨在评估主动脉内球囊反搏对严重冠状动脉狭窄时心肌内相性血流速度波形的影响。
在存在严重冠状动脉狭窄的情况下，尚不清楚主动脉内球囊反搏是否能增加舒张期心肌内血流或改变收缩期从心肌到壁外冠状动脉的逆行血流。
使用麻醉开胸犬（n = 7），在左主冠状动脉中引入严重狭窄，使狭窄后压力降至约60 mmHg（直径狭窄> 90%）。用20 MHz、80通道超声脉冲多普勒测速仪测量间隔动脉血流速度。同时测量左前降支动脉血流、主动脉压力和狭窄后远端冠状动脉压力。比较有无主动脉内球囊反搏时舒张期顺行血流积分和收缩期逆行血流积分。
尽管主动脉内球囊反搏增加了舒张期主动脉压力，但这种压力增加并未有效通过狭窄处传递。间隔动脉舒张期血流速度未增加，在主动脉内球囊反搏期间左前降支动脉血流无变化。
在存在严重冠状动脉狭窄的情况下，主动脉内球囊反搏未能增加心肌舒张期血流，也未增强从心肌到壁外冠状动脉的收缩期逆行血流。因此，主动脉内球囊反搏对严重冠状动脉狭窄缺血性心脏的主要作用可能是通过收缩期卸载降低氧需求来实现的。
