Treating acute "no-reflow" with intracoronary adenosine in 4 patients during percutaneous coronary intervention.

Angiographic evidence of impaired tissue perfusion, known as the "no-reflow" phenomenon, is a serious complication of percutaneous coronary intervention-one that is associated with increased mortality rates. Adenosine is an endogenous nucleoside that attenuates many of the mechanisms that are responsible for no-reflow. Herein, we report the cases of 4 patients who developed the no-reflow phenomenon after elective percutaneous coronary intervention to their native coronary arteries and saphenous vein grafts. In all 4 patients, and without adverse effects, small bolus doses of adenosine through the guiding catheter improved epicardial perfusion--measured by either Thrombolysis In Myocardial Infarction (TIMI) flow grade or corrected TIMI frame count-and tissue-level perfusion, graded according to myocardial blush. In view of adenosine's extremely short half-life in blood, the continuous administration of adenosine into the distal vascular bed throughout percutaneous coronary intervention may further improve outcomes by reversing or preventing the no-reflow phenomenon.