Detection of significant residual stenosis of the infarct-related artery after thrombolysis by high-dose dipyridamole echocardiography test: Is it detected often enough?

Abstract

Background and hypothesis: It has been reported that high-dose dipyridamole echocardiography test (DET) can be successfully used for the detection of critical residual stenosis of the infarct-related artery (IRA). However, we have recently noticed low sensitivity of DET for the detection of residual IRA stenosis in patients with single-vessel disease. This study sought to determine the value of DET for the detection of significant residual stenosis of the IRA after thrombolysis. Methods: Dipyridamole echocardiography test was performed in 55 consecutive patients after a first acute myocardial infarction before hospital discharge. All patients underwent coronary angiography 23 ± 6 days after infarction. Results: Nine of 19 patients with positive DET revealed new adjacent asynergy and all of the patients had patent and significantly stenotic IRA. Sensitivity and specificity of DET in identifying significant residual stenosis of the IRA were 24 and 100%, respectively. Among 49 patients with significantly stenotic or occluded IRA, 40 patients without adjacent asynergy during DET had higher baseline wall motion score index (WMSI) compared with 9 patients who revealed adjacent asynergy during DET (1.45 ± 0.30 vs. 1.24 ± 0.18; p<0.05). When all patients with positive DET (adjacent or remote asynergy) were compared with those with negative DET no difference in baseline WMSI was found (1.37 ± 0.24 vs. 1.44 ±0.24; p>0.05). Conclusions: Our data indicate that sensitivity of DET in detecting significant residual stenosis of the IRA after thrombolysis is low. It seems that the extent of myocardial infarction affects the ability of DET to detect adjacent, but not remote asynergy.