Preservation of Myocardial Microcirculation During Mechanical Reperfusion for Myocardial Ischemia With Either Abciximab or Eptifibatide

George Stoupakis, James Orlando, Harmit Kalia, Joan Skurick, Muhamed Saric, Rohit Arora; UMDNJ-New Jersey Medical School, Newark, NJ
 

ABSTRACT: Myocardial Blush Grade (MBG) is an angiographic method of assessing myocardial microcirculation and provides independent risk stratification among patients with normal TIMI 3 flow. The efficacy of abciximab and eptifibatide in the prevention of platelet aggregation and distal microembolization is unknown. We sought to compare the effect on myocardial perfusion between abciximab and eptifibatide following primary coronary intervention in stable angina or acute coronary syndrome.

Microcirculatory perfusion was reviewed in 101 consecutive patients (23 stable angina, 61 unstable angina, 17 Non q-MI) undergoing PTCA/stenting. One group of 51 patients an one group of 50 patients received standard bolus and infusion of abciximab and eptifibatide respectively. Angiograms were evaluated by 2 blinded independent reviewers for MBG as follows: 0, no blush; 1, minimal blush; 2, moderate blush; and 3, normal blush. TIMI 3 flow was seen in 98 patients. MBG scores were not significantly different in the abciximab group (67% MBG 3; 31% MBG 2; 2.0% MBG 0-1) than in the eptifibatide group (58% MBG 3; 36% MBG 2; 6.0% MBG 0-1 ), p=0.34. Patients with prior PTCA/stenting had lower MBG scores (0-2) compared to patients without prior PTCA (58% vs. 31%, p=0.03). There were significantly lower MBG scores in all patients with prior PTCA or CABG compared to patients without (55% vs. 30%, p=0.03). MBG scores significantly and inversely correlated with peak troponin I levels (r = -0.18, p = 0.04).

The lack of a difference in myocardial perfusion between abciximab and eptifibatide suggests that both compounds are equally effective in reducing platelet aggregation and microembolization during mechanical reperfusion. Lower MBG scores in patients with prior PTCA or revascularization may be explained by irreversible microvascular dysfunction resulting from distal microembolization during the previous procedure. Lower MBG scores in patients with higher troponin I levels may reflect more frequent microemboli and microinfarcts during an ischemic event. Larger prospective studies need to be performed to validate these findings.

Key words: microcirculation, glycoprotein llb/llla receptor antagonist, microembolization