[Improved occlusion tolerance time by continuous coronary perfusion with a modified Grüntzig coronary angioplasty...

We evaluated the modified Grüntzig coronary angioplasty catheter, which allows for continuous antegrade coronary perfusion during balloon occlusion without the use of an external pump. During in vitro tests the flow rates for effective pressure differences between aorta and distal coronary vessel in the range between 25 and 100 mm Hg were determined. During in vivo tests in 10 dogs the effect of balloon occlusion with continuous perfusion (OM) was compared with conventional occlusion without perfusion (OC). The occlusion tolerance time (OTZ) as determined by the appearance of unequivocal signs of ischemia in the ECG, was 486 +/- 77 s for OM versus 256 +/- 82 s for OC with a relative, individual increase of 191 +/- 54% (p less than 0.01, data are given +/- SEM). Observed ST-elevation was less with OM than with OC (0.22 +/- 0.05 versus 0.33 +/- 0.06, p less than 0.05). Occlusion related pressure difference between aorta and occluded coronary vessel was less with OM than with OC (31 +/- 8 mm Hg versus 40 +/- 10 mm Hg, p = 0.05). In selected cases such a prolongation of the intracoronary balloon occlusion time may represent a distinct advantage.