Optimal analysis of intravenous myocardial contrast echocardiography for predicting myocardial functional recovery in patients with acute myocardial infarction.
OBJECTIVE
This study attempted to determine the optimal interpretation method of intravenous myocardial contrast echocardiography (MCE) for predicting myocardial functional recovery in patients with acute myocardial infarction.


BACKGROUND
Assessment of the myocardial contrast effect is subjective and there is currently no universal agreement on the pulsing interval (PI) for imaging.


METHODS
Twenty-nine patients underwent percutaneous transluminal coronary angioplasty (PTCA) 4.8 +/- 1.9 days after acute myocardial infarction and intravenous MCE before and 24 hours after PTCA by using intermittent harmonic angioimaging at a series of PIs of 4, 8, 12, and 16 cardiac cycles. Adequate contrast enhancement was defined by homogeneous (MCEhomo score) and heterogeneous patterns (MCEheter score), and by a combination of intensity threshold and computed planimetry (MCEcom score). Adequate contrast enhancement at a shorter PI defined a higher MCE score (1 vs 5). The regional wall motion in the risk area was assessed before PTCA and 2 months after PTCA to evaluate functional recovery.


RESULTS
A significant improvement after PTCA was noted in the MCEhomo score (3.2 +/- 1.7 vs 3.6 +/- 1.7, P =.008) and the MCEcom score (2.9 +/- 1.6 vs 3.3 +/- 1.5, P <.0001), but not in the MCEheter score (4.3 +/- 1.3 vs 4.5 +/- 1.1, P =.058). Twenty-four hours after PTCA, segments with functional recovery had a higher MCEheter score (4.9 +/- 0.5 vs 3.8 +/- 1.6, P =.002), MCEhomo score (4.2 +/- 1.4 vs 2.6 +/- 1.9, P <.0001), and MCEcom score (3.8 +/- 1.2 vs 2.1 +/- 1.4, P <.0001) than those without. For the prediction of function recovery, MCEheter generally had a higher sensitivity but a lower specificity and accuracy than did MCEhomo and MCEcom. MCEcom had the best accuracy (83%) with a sensitivity of 95% and specificity of 61% at a PI of 16 cardiac cycles.


CONCLUSIONS
Using a combination of intensity threshold and computed planimetry for interpreting myocardial contrast enhancement at a long PI can optimize the value of MCE in predicting functional recovery after PTCA in patients with acute myocardial infarction.
Wang
Chao-Hung
CH
Cardiology Section, Department of Medicine, Chang Gung Medical College, Chang Gung Memorial Hospital, Keelung, Taiwan.
Cherng
Wen-Jin
WJ
Hung
Ming-Jui
MJ
Kuo
Li-Tang
LT
D000368:Aged; D015906:Angioplasty, Balloon, Coronary; D004452:Echocardiography; D005260:Female; D006321:Heart / Q000502:physiology*; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000000981:diagnostic imaging* / Q000503:physiopathology* / Q000628:therapy; D011237:Predictive Value of Tests; D011446:Prospective Studies; D020127:Recovery of Function / Q000502:physiology*; D012680:Sensitivity and Specificity; D013318:Stroke Volume / Q000502:physiology; D016896:Treatment Outcome