New Algorithm of Intra Aortic Balloon Pumping in Patients With Atrial Fibrillation

Abstract

Intra aortic balloon pumps have been operated inaccurately when used in patients with atrial fibrillation. In 36 pre-operative cardiac surgical patients with atrial fibrillation, the interval between the R wave of the electrocardiogram and the dicrotic notch (R-DCN interval) of the aortic pressure waveform showed significant correlation with the preceding R-R interval by second degree polynomial curves (0.53 < r2 < 0.74, p < 0.01). Based on these results a new algorithm for atrial fibrillation was designed. During brief off periods of the intra-aortic balloon pump in atrial fibrillation, electrocardiograms and aortic pressure waveforms were simultaneously recorded and analyzed to obtain a second degree polynomial curve between the preceding R-R and R-DCN intervals. The precise timing of balloon inflation was controlled using the equation in response to the preceding R-R interval. This new algorithm showed the smallest time lags (SD = 8.5 msec) when compared to other existing algorithms (the Kontron model-10, 53.49 msec; the Aries Medical model-700, 43.69 msec; the Datascope system-90, 25.98 msec; the Mansfield 3000, 19.65 msec; and the Kontron K-2000, 14.89 msec) in mock simulation driving using data obtained from clinically recorded waveforms.