Wave intensity analysis of para-aortic counterpulsation

作者：Lu Pong Jeu^*; Yang Chi Fu Jeffrey; Wu Meng Yu; Hung Chun Hao; Chan Ming Yao; Hsu Tzu Cheng

来源：American Journal of Physiology - Heart and Circulatory Physiology, 2012, 302(7): H1481-H1491.

DOI：10.1152/ajpheart.00551.2011

• counterpulsatile circulatory support
• heart failure
• coronary blood steal
• ventricular assist device
• arterial waves

Lu PJ, Yang CFJ, Wu MY, Hung CH, Chan MY, Hsu TC. Wave intensity analysis of para-aortic counterpulsation. Am J Physiol Heart Circ Physiol 302: H1481-H1491, 2012. First published January 6, 2012; doi: 10.1152/ajpheart. 00551.2011.-Wave intensity analysis (WIA) was used to delineate and maximize the efficacy of a newly developed para-aortic blood pump (PABP). The intra-aortic balloon pump (IABP) was employed as the comparison benchmark. Acute porcine experiments using eight pigs, randomly divided into IABP (n = 4) and PABP (n = 4) groups, were conducted to compare the characteristics of intra-and para-aortic counterpulsation. We measured pressure and velocity with probes installed in the left anterior descending coronary artery and aorta, during and without PABP assistance. Wave intensity for aortic and left coronary waves were derived from pressure and flow measurements with synchronization correction applied. To achieve maximized support efficacy, deflation timings ranging from 25 ms ahead of to 35 ms after the R-wave were tested. Similar to those associated with IABP counterpulsation, the PABP-generated backward-traveling waves predominantly drove aortic and coronary blood flows. However, in contrast with IABP counterpulsation, the nonocclusive nature of the PABP allowed systolic unloading to be delayed into early systole, which resulted in near elimination of coronary blood steal without diminution of systolic left ventricular ejection wave intensities. WIA can elucidate subtleties among different counterpulsatile support means with high sensitivity. Total accelerating wave intensity (TAWI), which was defined as the sum of the time integration of accelerated parts of the positive and negative wave intensities, was used to quantify counterpulsation efficacy. In general, the larger the TAWI gain, the better the counterpulsatile support efficacy. However, when PABP deflation timings were delayed to after the R-wave, the TAWI was found to be inversely correlated with coronary perfusion. In this delayed deflation timing setting, greater wave cancellation occurred, which led to decreased TAWI but increased coronary perfusion attributed to blood regurgitation reduction.

• 出版日期2012-4
• 单位长春大学