[Coronary flow reserve assessment by transthoracic color Doppler echocardiography after primary angioplasty: relationship with recovery of left ventricular function].

BACKGROUND

The aim of this study was to determine the relationship between coronary flow reserve measurement by transthoracic Doppler echocardiography in recent acute myocardial infarction treated with primary coronary angioplasty (PTCA) and recovery of left ventricular function.

METHODS

Forty-one consecutive patients (3 patients excluded for not good quality of the Doppler signal) have been studied with: (1) recent first acute myocardial infarction treated with primary PTCA within 6 hours of pain onset; (2) optimal angioplasty result with stent deployment, anti-IIb/IIIa infusion and TIMI 3 flow; (3) lack of type 1 diabetes and/or hypertension; (4) good tolerance to adenosine. Transthoracic Doppler echocardiography was used to record coronary flow velocities in the distal left anterior descending and posterior descending coronary arteries at rest and after infusion of adenosine. Coronary flow reserve was measured after 11 +/- 1 days from the acute event. The wall motion score index (WMSI) was calculated at baseline, 1 month and 3 months from myocardial infarction.

RESULTS

Patients of group A (n = 29 with coronary flow reserve > or = 1.6) showed a progressive and significant recovery of left ventricular function at follow-up. Patients of group B (n = 9 with coronary flow reserve < 1.6) had persistent left ventricular dysfunction at 3 months (ANOVA, p < 0.0001). WMSI was 1.64 +/- 0.26 in group A and 1.81 +/- 0.16 in group B (p = 0.09) at baseline; 1.30 +/- 0.26 in group A and 1.75 +/- 0.16 in group B (p < 0.0001) at 1 month; and 1.20 +/- 0.25 in group A and 1.73 +/- 0.17 in group B at 3 months. There was an inverse correlation between coronary flow reserve and WMSI at 1 month (r = -0.564, p < 0.0001), and at 3 months (r = -0.583, p < 0.0001). On multivariate analysis baseline WMSI and coronary flow reserve were the only predictors of 1-month WMSI recovery and of WMSI recovery at 3 months.

CONCLUSIONS

Coronary flow reserve by transthoracic color Doppler echocardiography is a useful method for predicting left ventricular function recovery in patients after primary PTCA.