Efficacy and safety of intracoronary epinephrine versus conventional treatments alone in STEMI patients with refractory coronary no‐reflow during primary PCI: The RESTORE observational study

Abstract

Objectives We aimed to compare intracoronary (IC) epinephrine versus conventional treatments alone in patients with ST‐elevation myocardial infarction and refractory coronary no‐reflow during primary percutaneous coronary intervention (PPCI). Methods Thirty consecutive patients with severe refractory coronary no‐reflow (TIMI 0–1, MBG 0–1) during PPCI were prospectively included after initial failure of conventional treatments. Conventional treatments used in both groups included IC nitrates, thrombectomy. Glycoprotein IIb/IIIa inhibitors and adenosine. Patients received IC epinephrine or no epinephrine. Results Intracoronary administration of epinephrine yielded significantly better coronary flow patterns (28.6% TIMI 3, 64.3% TIMI 2, 7.1% TIMI 1, and 0% TIMI 0), compared to those after treatment with conventional agents alone (18.8% TIMI 3, 12.5% TIMI 2, 37.5% TIMI 1, and 31.3% TIMI 0) (p value between groups = .004). In the IC epinephrine vs. no epinephrine group there was a significant reduction of 30‐day composite of death or heart failure (35.7% vs. 81.25%), improvement of ejection fraction (p = .01) and ST‐segment resolution (p = .01). Conclusions The findings of this proof‐of‐concept study suggest that as compared to use of conventional agents alone, IC epinephrine provides substantial improvement of coronary flow in STEMI patients with refractory no‐reflow during PPCI that may result into improved prognosis.

Intracoronary epinephrine and verapamil in the refractory no-reflow phenomenon in patients with acute myocardial infarction

“…The difference in the combined endpoint of death + heart failure reached statistical significance: 35,7 vs 81,25% (p=0,01). At the same time, left ventricular (LV) ejection fraction (EF) one day after the procedure in the adrenaline group increased significantly compared to the study before PCI: 44,57±8,20 vs 36,9%±13,9% (p=0,01), while the patients of the control group did not demonstrate such positive dynamics: 40,93±34,48 vs 38,31±14,70% (p=0,45) [11].…”

“…Taking into account the results of previous studies assessing the use of epinephrine in the setting of no-ref low phenomenon [11] and Using the Bland-Alrman method [15,16] for sample size calculation, we determined the minimum necessary number of patients enrolled in each group to be 30 (total 120), in order achieve 80% power with 0,05 statistical significance level.…”

“…IC epinephrine will be administered at a dose of 80-100 µg and verapamil at a dose of 500 µg. The dose of IC epinephrine was selected empirically and based on the experience of previous studies [10,11,13]. The dose of IC verapamil was selected based on the experience of previous studies [12,14].…”

The challenges of coronary no‐reflow phenomenon

“…There are both pharmacologic and device‐based strategies that have been proposed to resolve coronary no‐reflow (Table 1), but these strategies have not been fully validated in clinical trials. In this issue of Catheterization and Cardiovascular Interventions , Navarese et al 3 sought to compare intracoronary (IC) epinephrine versus conventional treatments alone in patients with STEMI and refractory coronary no‐reflow during PPCI.…”

REPLY: ITT (intrepret and test to effectively treat) approach for no‐reflow

“…Patients with refractory no‐reflow continue to experience worse outcomes owing to the failure of conventional agents. We appreciate the interest by Dr. Movahed to our study that is the first report comparing intracoronary epinephrine versus no epinephrine in ST‐elevation myocardial infarction patients with refractory no‐reflow to conventional treatments 1 …”