Prediction of myocardial functional recovery by noninvasive evaluation of Basal and hyperemic coronary flow in patients with previous myocardial infarction.

BACKGROUND: The aim of this study was to evaluate the relation of basal and hyperemic coronary flow with myocardial functional improvement in patients with previous myocardial infarction undergoing elective percutaneous coronary intervention (PCI).
METHODS: Coronary flow was measured using transthoracic Doppler echocardiography in 50 patients (41 men; mean age, 53 ± 8 years) with previous myocardial infarction before, 24 hours, and 3 months after elective PCI. Diastolic deceleration time (DDT) was measured from the peak diastolic velocity to the point of intercept of initial decay slope with baseline. Coronary flow reserve (CFR) was calculated as the ratio of hyperemic to basal peak diastolic flow velocities.
RESULTS: In comparison with patients without improvements in left ventricular function, patients with recovered left ventricular function had longer DDTs before angioplasty (841 ± 286 vs. 435 ± 80 msec, P < .001). CFR was significantly higher in recovered compared with nonrecovered patients (2.60 ± 0.70 vs. 2.16 ± 0.34, P = .034) 24 hours after PCI. Global and regional wall motion scores before PCI, end-diastolic and end-systolic volumes, and CFR 24 hours after PCI and DDT before PCI were univariate predictors of left ventricular functional recovery. By multivariate analysis, DDT and regional wall motion score before PCI were independent predictors of left ventricular recovery in the follow-up period (P = .003 and P = .007, respectively).
CONCLUSIONS: In patients with previous myocardial infarction undergoing elective PCI, evaluation of basal coronary flow pattern and measurement of DDT before angioplasty may predict functional improvement of myocardium in the follow-up period and could be useful quantitative parameters in the evaluation of potential improvement in myocardial function.