[Comparison of myocardial contrast echocardiography and 99mTc MIBI single photon emission computed tomography in the assessment of myocardial perfusion in patients with acute myocardial infarction].

UNLABELLED

The myocardial perfusion assessment in myocardial infarction is crucial to proper therapeutical decisions and patient's prognosis. The aim of the study to assess the efficacy of intravenous contrast echocardiography (MCE) in detecting myocardial perfusion defects in patients with acute myocardial infarction compared with 99mTc MIBI SPECT study.

MATERIAL AND METHODS

86 patients (mean age 58.4 +/- 11.2) underwent primary percutaneous coronary (PCI) for acute anterior myocardial infarction. TIMI grade flow, myocardial blush grade (TMPG), corrected TIMI frame count (cTFC) and segmental contractility and segmental perfusion were estimated in real time before and immediately after PCI, using injections of intravenous Optison. MCE performed before PCI described the risk area as the sum of segments with the lack of perfusion. A MCE perfusion defect size after PCI < 25% of the MCE perfusion defect size before PCI was used to define myocardial reperfusion. MCE was repeated on the third day after PCI. All patients underwent a rest 99mTc MIBI SPECT study (SPECT) on the third day after PCI.

RESULTS

Based on MCE, 54 patients had reperfusion ("reflow" group) and 32 had non-reperfusion ("no-reflow" group). Patients from the non-reperfusion group showed a higher creatine kinase peak (p = 0.0034), higher kinase-MB (p = 0.0033) and higher troponine level (p = 0.0629), longer time span between the onset of pain and reperfusion (p = 0.003), and worse baseline regional contractile function (p = 0.0022). All angiographic parameters were worse in this group before as well as after PCI: more often TIMI 0 or 1, TMPG 0 or 1 in patients from "no-reflow" group was observed. These patients had higher cTFC than ones from "reflow" group. The agreement between MCE and SPECT for detecting perfusion abnormality was 87%.

CONCLUSIONS

MCE facilitated identification of myocardial perfusion abnormalities in patients with acute myocardial infarction, whereas serial MCE facilitated identification of patients with early and late improvement of myocardial perfusion. MCE correlated very well with SPECT images in assessing perfusion defect.