OBJECTIVES We assessed whether the intravenous administration of nicorandil
, an adenosine triphosphate (ATP)-sensitive K+ channel opener, exerts benef
icial effect-on microvascular function and functional and clinical outcomes
in patients with acute myocardial infarction (AMI).
BACKGROUND Experimental studies documented that ATP-sensitive K+ channel op
ener exerts cardioprotection after prolonged ischemia.
METHODS We randomly divided 81 patients with a first anterior AMI into two
groups, nicorandil (n = 40) and control groups (n = 41). All patients recei
ved successful coronary angioplasty within 12 h after the symptom onset and
underwent myocardial contrast echcardiography (MCE) with the intracoronary
injection of sonicated microbubbles. In the nicorandil group, we injected
4 mg of nicorandil followed by the infusion at 6 mg/h for 24 h and by oral
nicorandil (15 mg/day).
RESULTS The improvement in regional left ventricular function, nail motion
score and regional wall motion was significantly better in the nicorandil g
roup then in the control group. Intractable congestive heart failure, malig
nant ventricular arrhythmia and pericardial effusion were more frequently f
ound in the control group than in the nicorandil group (15% vs. 37%, 5% vs.
20% and 8% vs. 37%, p < 0.05, respectively). The frequency of sizable MCE
no reflow phenomenon was significantly lower in the nicorandil group than i
n the control group (15% vs. 33%, p < 0.05).
CONCLUSIONS Intravenous nicorandil in conjunction with coronary angioplasty
is associated with better functional and clinical outcomes compared to ang
ioplasty alone in patients with an anterior AMI. Myocardial contrast echoca
rdiography findings imply that an improvement in microvascular function wit
h nicorandil may be attributable to this better outcome. CT Am (C) 1999 by
the American College of Cardiology.