Prediction of short- and intermediate-term prognoses of patients with acute myocardial infarction using myocardial contrast echocardiography one day after recanalization.
OBJECTIVE
This study sought to determine whether microvascular integrity in the risk area (RA) for myocardial infarction (MI) one day after recanalization predicts the outcome in patients with first acute MI.


BACKGROUND
Immediately after recanalization, microcirculation in the RA is modified by both hyperemic response and microvascular impairment.


METHODS
Fifty consecutive patients who underwent serial myocardial contrast echocardiography before and one day after recanalization (day 2) were studied. All patients had a completely occluded lesion in the left anterior descending coronary artery alone, and underwent successful reperfusion therapy. The relative size of the initial RA (RA ratio) and peak gray scale ratio (PGSR) within the RA on day 2 were determined. Patients were followed for a median of 22 months to evaluate clinical outcome.


RESULTS
On day 2, PGSR was a median of 0.46. Study patients were subdivided into two groups, group A of 24 patients with acceptable opacification (PGSR > 0.46 on day 2) and group B of 26 patients without it. Major cardiac events (cardiac death, nonfatal MI and repeat admission for congestive heart failure) were more frequently observed in group B (28% vs. 4%, Cox hazard ratio=8.5, p=0.05, 95% confidence interval [CI] 1.03 to 69.9). The median value of the RA ratio was 0.45. Patients (n=15) with RA ratio > 0.45 on day 1 and PGSR on day 2 < or = 0.46 exhibited a 10.7-fold relative risk for major cardiac events (p=0.005, 95% CI 2.06 to 55.8) and a 3.69-fold relative risk for composite cardiac events (major cardiac events and target lesion revascularizations) after the initial intervention (p=0.004, 95% CI 1.51 to 9.04).


CONCLUSIONS
The assessment of both the size of the initial RA and microvascular integrity on day 2 enables precise determination of the efficacy of reperfusion therapy and prediction of the short- and intermediate-term prognoses of patients with recanalized MI.
Sakuma
T
T
Division of Cardiology, Akane Foundation Tsuchiya General Hospital, Hiroshima, Japan. sakuma@urban.ne.jp
Hayashi
Y
Y
Sumii
K
K
Imazu
M
M
Yamakido
M
M
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003287:Contrast Media; D017023:Coronary Angiography; D004452:Echocardiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007485:Ioxaglic Acid; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications / Q000000981:diagnostic imaging / Q000188:drug therapy*; D015588:Observer Variation; D011237:Predictive Value of Tests; D011379:Prognosis; D015203:Reproducibility of Results; D015912:Thrombolytic Therapy; D013997:Time Factors
D003287:Contrast Media; D007485:Ioxaglic Acid