Early and rapid prediction of patency of the infarct-related coronary artery by using left ventricular wall thickness as measured by two-dimensional echocardiography.

OBJECTIVES

The aim of this study was to determine whether echocardiography can distinguish between persistent coronary occlusion and reperfusion.

BACKGROUND

There are no adequate clinical or noninvasive laboratory markers to accurately predict successful reperfusion in an acute myocardial infarction.

METHODS

In a closed chest swine model, the effect of reperfusion on myocardial wall thickness was studied by comparing a 150-min total coronary artery occlusion (group 1) with 120 min of occlusion followed by 30 min of reperfusion (group 2) in the area of risk as measured by echocardiography. Wall thickness was measured at baseline and at 90 and 150 min.

RESULTS

In group 1 (n = 4), there was no appreciable change in mean wall thickness from 90 min to 150 min of occlusion at either end-diastole or end-systole (0.54 +/- 0.02 to 0.52 +/- 0.03 cm, 0.55 +/- 0.03 to 0.54 +/- 0.03 cm, respectively; p = NS). In contrast, in group 2 (n = 6), an increase in mean wall thickness from 0.53 +/- 0.02 to 0.97 +/- 0.05 cm at end-diastole and from 0.56 +/- 0.04 to 1.04 +/- 0.07 cm at end-systole was found from 90 min of occlusion to 30 min of reperfusion (p < 0.001). Reperfusion resulted in an increase in wall thickness of 83 +/- 11% at end-diastole and 92 +/- 17% at end-systole. In contrast, persistent coronary occlusion showed minimal changes of -3.0 +/- 5% at end-diastole and -2.0 +/- 6% at end-systole.

CONCLUSIONS

This study confirms the hypothesis that an increase in wall thickness can accurately distinguish between reperfusion and permanent coronary occlusion.