Intracoronary epinephrine in the treatment of refractory no-reflow after primary percutaneous coronary intervention: a retrospective study.

Background: Despite the advances in medical and interventional treatment modalities, some patients develop epicardial coronary artery reperfusion but not myocardial reperfusion after primary percutaneous coronary intervention (PCI), known as no-reflow. The goal of this study was to evaluate the safety and efficacy of intracoronary epinephrine in reversing refractory no-reflow during primary PCI.

Methods: A total of 248 consecutive STEMI patients who had undergone primary PCI were retrospectively evaluated. Among those, 12 patients which received intracoronary epinephrine to treat a refractory no-reflow phenomenon were evaluated. Refractory no-reflow was defined as persistent TIMI flow grade (TFG) ≤ 2 despite intracoronary administration of at least one other pharmacologic intervention. TFG, TIMI frame count (TFC), and TIMI myocardial perfusion grade (TMPG) were recorded before and after intracoronary epinephrine administration.

Results: A mean of 333 ± 123 mcg of intracoronary epinephrine was administered. No-reflow was successfully reversed with complete restoration of TIMI 3 flow in 9 of 12 patients (75%). TFG improved from 1.33 ± 0.49 prior to epinephrine to 2.66 ± 0.65 after the treatment (p < 0.001). There was an improvement in coronary flow of at least one TFG in 11 (93%) patients, two TFG in 5 (42%) cases. TFC decreased from 56 ± 10 at the time of no-reflow to 19 ± 11 (p < 0.001). A reduction of TMPG from 0.83 ± 0.71 to 2.58 ± 0.66 was detected after epinephrine bolus (p < 0.001). Epinephrine administration was well tolerated without serious adverse hemodynamic or chronotropic effects. Intracoronary epinephrine resulted in significant but tolerable increase in heart rate (68 ± 13 to 95 ± 16 beats/min; p < 0.001) and systolic blood pressure (94 ± 18 to 140 ± 20; p < 0.001). Hypotension associated with no-reflow developed in 5 (42%) patients. During the procedure, intra-aortic balloon pump counterpulsation was required in two (17%) patients, transvenous pacing in 2 (17%) cases, and both intra-aortic balloon counterpulsation and transvenous pacing in one (8%) patients. One patient (8%) died despite all therapeutic measures.

Conclusion: Intracoronary epinephrine may become an effective alternative in patients suffering refractory no-reflow following primary PCI.