Adenosine use during aortocoronary vein graft interventions reverses but does not prevent the slow-no reflow phenomenon

Slow or no reflow (SNR) complicates 10-15% of cases of percutaneous interve ntion (PI) in saphenous vein bypass graft (SVG). To date there have been li mited options for the prevention and treatment of this common and potential ly serious complication. We evaluated the procedural outcome of 143 consecu tive SVG interventions. We compared patients who received pre-intervention intra-graft adenosine boluses with those who did not. In addition we examin ed the efficacy of adenosine boluses to reverse slow-no reflow events. Angi ograms were reviewed and flow graded (TIMI grade) by film readers blinded t o the use of any intraprocedural drug or clinical history. Seventy patients received intragraft adenosine boluses before percutaneous intervention (AP PI), 73 received no preintervention adenosine (NoAPPI). There were no signi ficant angiographic differences between the two groups at baseline. A total of 20 patients experienced SNR. The incidence of SNR was similar in the tw o groups (APPI = 14.2% vs. NoAPPI = 13.6%, P = 0.9). SNR was treated with r epeated, rapid boluses (24 mug each) of intra-graft adenosine. Reversal of SNR was observed in 10 of 11 patients (91%) who received high doses of aden osine (greater than or equal to5 boluses, mean 7.7 +/- 2.6) and in 3 of 9 ( 33%) of those who received low doses (<5 boluses, mean 1.5 +/- 1.2). Final TIMI flow was significantly better in the high dose than in the low dose gr oup (final TIMI 2.7 +/- 0.6 vs. 2 +/- 0.8, P = 0.04). No significant untowa rd complications were observed during adenosine infusion. These findings su ggest that SNR after PI in SVG is not prevented by pre-intervention adenosi ne, but it can be safely and effectively reversed by delivery of multiple, rapid and repeated boluses of 24 <mu>g of intra-graft adenosine. Cathet Car diovasc. Intervent. 51:394-399, 2000. (C) 200 Wiley-Liss, Inc.