Acute assessment of microvascular perfusion patterns by myocardial contrast echocardiography during myocardial infarction: relation to timing and extent of functional recovery

Objective-To examine the relation between the initial microvascular perfusi on pattern, as assessed by intracoronary myocardial contrast echocardiograp hy ((MCE), immediately after restoration of TIMI (thrombolysis in myocardia l infarction) (TIMI) grade 3 flow during acute myocardial infarction, and t he extent and timing of functional recovery in the area at risk. Setting-Referral centre for interventional cardiology. Methods-Intracoronary MCE was performed 15 minutes after TIMI grade 3 recan alisation of the infarct artery in 25 patients. Segmental myocardial contra st patterns were graded semiquantitatively (0, none; 0.5, heterogeneous; 1, homogeneous). Functional recovery was assessed by echocardiography on days 9 and 42. Results-Among 174 myocardial segments in the area at risk, wall motion reco very on day 9 was observed in 40% of MCE grade 1 segments but there was no significant recovery in grade 0 or 0.5 segments. On day 42, recovery had oc curred in 56% of MCE grade 1 segments (p < 0.0001 v MCE grade 0 and 0.5; p = 0.0001 v MCE grade 1 on day 9), and 22% of MCE grade 0.5 segments (p = 0. 02 v MCE grade 0; p = 0.0005 v MCE grade 0.5 on day 9); MCE grade 0 segment s did not recover. Negative predictive value in predicting recovery by cont rast enhancement was 95% and 89% by days 9 and 42, respectively. Conclusions-Contractile recovery occurs earliest in well reperfused segment s. Up to one quarter of segments with heterogeneous contrast enhancement sh ow wall motion recovery within the first six weeks. Myocardial perfusion af ter recanalisation in acute myocardial infarction, even if heterogeneous, i s a prerequisite for postischaemic functional recovery. Thus preservation o f acute myocardial perfusion is associated with more complete and early fun ctional recovery.