Theoretical Establishment of a New Algorithm for Intra-Aortic Balloon Pumping for the Patients with Atrial Fibrillation, and Its Clinical Application.

房颤患者左室舒张末期容积受左室充盈时间（即ECG上的R-R间期）调节。基于此，我们设计了一种新的IABP气囊充气时间由前R-R间隔与中央主动脉压R-dicrotic缺口间隔之间的回归方程决定的算法，并将该算法与其他5种商用驱动程序的算法进行了比较。【方法】在本课题第一年对二次回归方程进行分析并建立统计拟合优度的基础上，我们使用心房颤动患者在心脏手术后立即应用主动脉内球囊泵送的心电图和中央主动脉压波同时记录的新算法进行测试。最后，我们发明了一种新的主动脉内球囊泵送驱动程序，该驱动程序在主动脉内球囊泵送周期性短停时自动计算出先前R-R间隔与R-dicrotic缺口间隔之间的二次回归方程，并利用新计算的方程重新调整球囊充气的最佳时机。[结果]二次方程具有统计学显著性和良好的拟合性，但在R-R区间大于900 mesc时，各参数之间呈线性关系。决定性系数值分布在0.6 ~ 0.75之间。在与市买驱动程序算法的对比研究中，新算法显示出最优的时间点，最佳膨胀时间点（主动脉dicrotic切迹）与真实时间点的时间差标准差（sd）与其他5种驱动程序相比值最小，具有统计学意义。新算法的sd值为8.50 msec。其中，对房颤反应最好的是Kontron K-2000，为14.89 msec。算法无效的AVCO模型-10，平均为54.44毫秒。最后，我们为房颤患者制作了一个新的驱动程序，并应用于临床，血流动力学得到了明显的改善。少

In a case with atrial fibrillation, left ventricular(LV) end-diastolic volume is regulated by LV filling time (namely, preceding R-R interval on ECG). From this view point, we devised a new algorithm that the timing of IABP balloon inflation is decided by a regression equation between preceding R-R interval and interval of R-dicrotic notch in central aortic pressure, and compared the new algorithm with other five algorithms used in commercially available drivers.[Methods] on the basis of secondary regression equations which were analyzed and established statistical goodness of fit in the 1st year of this research project, we tested this new algorithm using the ECG and central aortic pressure waves recorded simultaneously from the patients with atrial fibrillation who had undergone cardiac operation and applied intra-aortic balloon pumping immediately after the surgery. Finally, we invented a new driver for intra-aortic balloon pumping, in which the secondary regression equation between … More preceding R-R interval and R-dicrotic notch interval is calculated automatically during the periodical short stop of the intra-aortic balloon pumping and the optimal timing of balloon inflation is readjust using newly calculated equation.[Results] The secondary equations were revealed statistical significance and good fitness but the relationship between these parameters became liner in the R-R interval longer than 900 mesc. and the decisive coefficient value were distributed from 0.6 to 0.75. In the comparative study of this new algorithm with the algorithms used in commercially available drivers, the new algorithm showed most optimal timing and the standard deviation(S.D.) of timing difference between the best inflation timing (aortic dicrotic notch) and the true timing of this new algorithm showed smallest value with statistical significance compared with other five drivers. The S.D. value in new algorithm was 8.50 msec., Kontron K-2000, which had most excellent response to atrial fibrillation, showed 14.89 msec. and AVCO model-10, which had ineffective algorithm, 54.44 msec. Lastly, we made a new driver regulated by this new optimal algorithm for the patients with atrial fibrillation and applied clinically with marked hemodynamic improvements. Less