Khir Ashraf W, Price Susanna, Henein Michael Y, Parker Kim H, Pepper John R
Department of Bioengineering, Imperial College, Exhibition Rd., London, SW7 2AZ, UK.
Eur J Cardiothorac Surg. 2003 Aug;24(2):277-82. doi: 10.1016/s1010-7940(03)00268-9.
The intra-aortic balloon pump is the most widely used form of temporary cardiac assist and often utilised in patients before and after cardiac surgery. Several effects of balloon counter-pulsation have been reported previously, but its effect on left ventricular diastolic function has not been thoroughly investigated. The aim of this study is to examine the effect of the intra-aortic balloon pump on left ventricular wall motion and transmitral flow.
We studied 20 patients in the intensive care unit, less than 36 h following cardiac surgery. We recorded left anterior descending coronary artery and transmitral E-wave flow velocities using transesophageal echocardiography pulsed Doppler. We also recorded left ventricular long axis free-wall movement using M-mode. The intra-aortic balloon pump was set to full augmentation and recordings were made at pumping cycles 1:1, 1:2, 1:3, and when the pump was on stand-by, leaving a minimum of 5 min between the pumping modes to allow the return to control conditions. In order to eliminate time effects, the sequence of recording was varied between patients using a 4 by 4 Latin-square.
The peak diastolic left anterior descending coronary artery and transmitral E-wave flow velocities, and left ventricular free-wall early diastolic lengthening velocity increased significantly with intra-aortic balloon pumping cycles 1:1, 1:2 and 1:3 compared to their value with the pump on stand-by, all P < 0.001. The increase in peak transmitral E-wave flow velocity correlated with the increase in peak left anterior descending coronary artery diastolic flow velocity (r = 0.74, P = 0.02), and with the increase in left ventricular free-wall early diastolic lengthening velocity (r = 0.80, P < 0.001).
Using the intra-aortic balloon pump post-cardiac surgery significantly increases peak diastolic left anterior descending coronary artery flow velocities and left ventricular free-wall early diastolic lengthening velocity, whose increase explains the increase in peak transmitral E-wave velocity. Although coronary flow is epicardial and mitral flow is intracardial, their close relationship suggests an improvement in left ventricular diastolic function with intra-aortic balloon pump.
主动脉内球囊反搏是最广泛使用的临时心脏辅助形式，常用于心脏手术前后的患者。此前已报道了球囊反搏的多种效应，但其对左心室舒张功能的影响尚未得到充分研究。本研究的目的是探讨主动脉内球囊反搏对左心室壁运动和二尖瓣血流的影响。
我们研究了20例心脏手术后不到36小时入住重症监护病房的患者。我们使用经食管超声心动图脉冲多普勒记录左前降支冠状动脉和二尖瓣E波血流速度。我们还使用M型记录左心室长轴游离壁运动。将主动脉内球囊反搏设置为全增强模式，并在泵血周期1:1、1:2、1:3以及泵处于备用状态时进行记录，各泵血模式之间至少留出5分钟以恢复至对照状态。为消除时间效应，采用4×4拉丁方在患者之间改变记录顺序。
与泵处于备用状态时相比，在泵血周期1:1、1:2和1:3时，舒张期左前降支冠状动脉和二尖瓣E波血流速度峰值以及左心室游离壁舒张早期延长速度显著增加，所有P<0.001。二尖瓣E波血流速度峰值的增加与左前降支冠状动脉舒张期血流速度峰值的增加相关（r = 0.74，P = 0.02），并与左心室游离壁舒张早期延长速度的增加相关（r = 0.80，P<0.001）。
心脏手术后使用主动脉内球囊反搏可显著增加舒张期左前降支冠状动脉血流速度峰值和左心室游离壁舒张早期延长速度，其增加解释了二尖瓣E波速度峰值的增加。虽然冠状动脉血流是心外膜的，二尖瓣血流是心内的，但它们的密切关系表明主动脉内球囊反搏可改善左心室舒张功能。
