Detection of no-reflow zones using intra venous ultrasound contrast and intermittent harmonic imaging in patients with acute myocardial infarction and angiographically successful recanalization

Intermittent Harmonic Ultrasound Imaging (IHI) following intravenous perfluorocarbon exposed sonicated dextrose albumin (PESDA) microbubble injections (MBI) has identified myocardial perfusion abnormalities due to ischemia. Since intracoronary MBI have also detected no-reflow zones (NRZ) in acute myocardial infarction (AMI), we hypothesized that IHI with IV PESDA could may also detect NRZ in this same setting. Accordingly, we gave 0.000625 to 0.00125 ml/kg doses of PESDA during IHI in 18 patients (pts) with AMI (2.1 ±1.3 days after AMI). All 18 had quantitative angiograms and TIMI grading of flow in the infarct vessel (IV). Peak myocardial video intensity (PMVI) in the infarct zone (IZ) and the ratio of PMVI in the IZ to a non-IZ were measured, as well as a visual regional myocardial contrast score (MCS) graded as 1=normal, 2=mildly reduced, l^severely reduced contrast in the IZ. In the five pts with TIMI 0-2 flow in the IV, all had a PMVI ratio <0.6 and 4/5 had a MCS≥2 in the IZ. Seven of 13 pts with TIMI 3 now in the IV had a MCS≥2 in the IZ (Group I), while in the remaining 6 (Group II), MCS was normal. There were no differences in wall motion score in the IZ between the two groups (2.6±0.7 Group I, 1.8 ±0.7 Group 11), or use of ehrombolytics. Multivessel disease was present in 5/7 Group I and only 1/6 Group II pts. An example in two different pts: TIMI 3 flow;No Reflow-IHI TIMS 3 Flow;Normal MCS- IHI We conclude the IHI with IV PESDA can non-invasively identify NRZ in patients with AMI. Over 50% of patients with angiographically TIMI grade III flow after recanalization in AMI still have evidence of no reflow with IHI.