Abstract
Background The effects of intraaortic balloon pumping (IABP) are considered to be a reduction in myocardial oxygen demand because of systolic left ventricular unloading and an increase in coronary blood flow. Although the former effect has been consistently recognized, the latter effect remains controversial. The purpose of this study was to examine the effects of IABP on the angiographic no-reflow phenomenon. Methods and Results The coronary flow velocity pattern of the left anterior descending artery (LAD) was assessed by transthoracic Doppler echocardiography during IABP counterpulsation, and the effects of IABP were compared between angiographic no-reflow and good reflow patients. The study group comprised 17 patients with anterior myocardial infarction who underwent percutaneous coronary intervention and IABP for typical clinical indications. Echocardiographic data were obtained during 2:1 balloon pumping after coronary angioplasty. In the good reflow group (n=9), IABP counterpulsation increased the mean diastolic flow velocity (MDFV) and peak diastolic flow velocity (PDFV) by 56±32% (p<0.001) and 48±27% (p<0.001), respectively. In contrast, in the no-reflow group (n=8), IABP only increased the MDFV and PDFV by 19±33% (p=0.24) and 6±12% (p=0.22), respectively. Diastolic deceleration time was smaller and the prevalence of systolic retrograde flow was greater in the no-reflow group than in the good reflow group, and IABP affected neither parameter. Conclusions IABP had limited effects on LAD flow velocity pattern in patients with the angiographic no-reflow phenomenon. (Circ J 2006; 70: 37 - 43)
