| Title | Usefulness of myocardial contrast echocardiography using low-power continuous imaging early after acute myocardial infarction to predict late functional left ventricular recovery. | | Author(s) | Janardhanan R, Swinburn JM, Greaves K, Senior R | | Institution | Department of Cardiovascular Medicine, Northwick Park Hospital, Harrow, United Kingdom. | | Source | Am J Cardiol 2003 Sep 1; 92(5):493-7. | | MeSH | Aged
Albumins
Blood Flow Velocity
Confounding Factors (Epidemiology)
Contrast Media
Creatine Kinase
Echocardiography
Female
Fluorocarbons
Humans
Male
Middle Aged
Myocardial Infarction
Myocardial Reperfusion
Necrosis
Predictive Value of Tests
Recovery of Function
Research Support, Non-U.S. Gov't
Sensitivity and Specificity
Stroke Volume
Time Factors
Treatment Outcome
Ventricular Function, Left
| | Abstract | Microvascular perfusion is a prerequisite for ensuring viability early after acute myocardial infarction (AMI). For adequate assessment of myocardial perfusion, both myocardial blood volume and velocity need to be evaluated. Due to its high frame rate, low-power continuous myocardial contrast echocardiography (MCE) can rapidly assess these parameters of myocardial perfusion. We hypothesized that the technique can accurately differentiate necrotic from viable myocardium after reperfusion therapy in AMI. Accordingly, 50 patients underwent low-power continuous MCE using intravenous Optison (Amersham Health, Amersham, Middlesex, United Kingdom) 7 to 10 days after AMI. Myocardial perfusion (contrast opacification assessed over 15 cardiac cycles after the destruction of microbubbles with high energy pulses) and wall thickening were assessed at baseline. Regional and global left ventricular (LV) function was reassessed after 12 weeks. Out of the 297 dysfunctional segments, MCE detected no contrast enhancement during 15 cardiac cycles in 172 segments, of which 160 (93%) failed to show improvement. MCE demonstrated contrast opacification during 15 cardiac cycles in 77 segments, of which 65 (84%) showed recovery of function. The greater the extent and intensity of contrast opacification, the better the LV function at 3 months (p <0.001, r = -0.91). Almost all patients (94%) with <20% perfusion in dysfunctional myocardium (assessing various cut-offs) failed to demonstrate an improvement in LV function. MCE and peak creatine kinase proved to be independent predictors of functional recovery (p <0.001). In conclusion, low-power continuous MCE is an accurate and rapid bedside technique to identify microvascular perfusion after AMI. This technique may be utilized to reliably predict late recovery of function in dysfunctional myocardium after AMI. | | Language | eng | | Pub Type(s) | Journal Article
Validation Studies
| | PubMed ID | 12943865 |
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