Time course of impaired coronary flow reserve after reperfusion in patients with acute myocardial infarction.
To evaluate the time course of coronary flow reserve after reperfusion, 14 patients with a first anterior wall acute myocardial infarction who underwent successful coronary angioplasty within 6 hours after symptom onset were studied. After angioplasty, coronary flow reserve of the left anterior descending artery was measured with a coronary Doppler guidewire and intravenous dipyridamole (0.56 mg/kg over 4 minutes). Measurements were repeated at predischarge (16 +/- 3 days, n = 12) and at follow-up (6 +/- 3 months, n = 9). Patients with restenosis at the time of repeat catheterization were excluded. An additional 13 patients with normal angiograms served as reference patients. Coronary flow reserve was 1.33 +/- 0.29 after angioplasty. It increased to 1.88 +/- 0.36 at predischarge (p <0.01) and further to 2.34 +/- 0.38 at follow-up (p <0.01 vs after angioplasty and at predischarge, respectively). However, compared with reference patients (3.15 +/- 0.48), coronary flow reserve was significantly reduced in the infarct patients even at follow-up (p <0.01). In infarct patients, the infarct region wall motion was initially -3.86 +/- 0.67 SD/chord. It significantly improved to -2.07 +/- 1.04 SD/chord at predischarge (p <0.01) and to -1.67 +/- 1.43 SD/chord at follow-up (p <0.01). However, there was no significant relation between coronary flow reserve and region wall motion after angioplasty (r = 0.10), at predischarge (r = 0.35), and at follow-up (r = 0.28). Thus, coronary flow reserve is severely impaired early after reperfusion. Coronary flow reserve improves over 2 weeks, but the impairment persists at 6 months after acute myocardial infarction. The impairment of coronary flow reserve cannot be predicted by left ventricular function. Small sample size is a potential limitation of this study, and a larger study should be performed to confirm these findings.
Department of Cardiology, Hiroshima City Hospital, Japan.
M
M
Ishihara
H
H
Sato
H
H
Tateishi
T
T
Kawagoe
Y
Y
Shimatani
S
S
Kurisu
K
K
Sakai
D000368:Aged; D015906:Angioplasty, Balloon, Coronary; D001783:Blood Flow Velocity; D006328:Cardiac Catheterization; D017023:Coronary Angiography; D003326:Coronary Circulation / Q000502:physiology*; D004176:Dipyridamole; D005260:Female; D005500:Follow-Up Studies; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis / Q000503:physiopathology* / Q000628:therapy*; D015425:Myocardial Reperfusion / Q000009:adverse effects*; D018608:Ultrasonography, Doppler; D016277:Ventricular Function, Left / Q000502:physiology
D004176:Dipyridamole