Ascending versus descending aortic balloon pumping: organ and myocardial perfusion during ischemia.

BACKGROUND: The ICS-Supracor (Abiomed, Danvers, MA) is a preshaped ascending aorta balloon pump. We compared the effects of this catheter with the classical descending intraaortic balloon pump (IABP). The study focused on hemodynamic effects, myocardial blood flow in normal and ischemic regions, cerebral perfusion, and peripheral organ perfusion.

METHODS: We placed a stenosis on the lateral branch of the coronary artery to reduce flow 50% (sheep). Measurements included hemodynamic changes, myocardial blood flow, and organ flow (colored microspheres) at baseline, after stenosis, during IABP support, and during ICS support.

RESULTS: Counterpulsation with the ICS led to a significantly higher peak diastolic aortic augmentation than with the IABP (IABP, 99 +/- 14 mm Hg; ICS, 140 +/- 29 mm Hg; p = 0.003). There was no significant change in cerebral perfusion or peripheral organ perfusion. Myocardial blood perfusion was significantly increased by the IABP as well as the ICS. This effect was seen in ischemic and nonischemic regions (subendocardial and subepicardial). The ICS improved myocardial blood flow significantly more than the IABP (IABP, 0.65 +/- 0.1 mL/min/g; ICS, 0.94 +/- 0.06 mL/min/g; p = 0.0005).

CONCLUSIONS: The ICS increases myocardial blood flow in ischemic regions significantly more than the IABP, without impairment of cerebral flow. Assessment of vascular complications, peripherally and in the ascending aorta, has to await results of clinical trials.