Abstract 19159: Assessment of Myocardial Viability After Acute Myocardial Infarction: A Head-to-head Comparison of the Perfusable Tissue Index by PET and Delayed Contrast-enhanced CMR
Introduction: Early recognition of viable myocardium is of great clinical importance after acute myocardial infarction (AMI). Delayed contrast-enhanced magnetic resonance imaging (DCE-CMR) has been validated extensively for the detection of viability. An alternative method for detecting viability is the perfusable tissue index (PTI), a positron emission tomography (PET) derived parameter, which is inversely related to the extent of myocardial scar (nonperfusable tissue).
Aims: To investigate the predictive value of PTI on recovery of LV function after percutaneous coronary intervention (PCI) for AMI.
Methods: Twenty-six patients with AMI successfully treated by PCI were included. Subjects were examined one week and three months after AMI with [15O]H2O PET and DCE-CMR to assess PTI, regional function and scar. Viability was defined as recovery of systolic wall thickening (SWT) ≥ 3.0 mm at follow-up.
Results: A total of 396 segments were available for serial analysis. At baseline, 166 segments were dysfunctional, of which 125 (75%) exhibited significant DCE and were located in the myocardial territory supplied by the culprit-artery. Fourty-nine of these dysfunctional segments showed full recovery during follow-up (viable), whereas 76 segments remained dysfunctional (nonviable). Baseline PTI of viable segments was 0.94 ± 0.07 and was significantly higher compared to nonviable segments (0.80 ± 0.11, p = 0.01). The optimal cut-off value for the PTI was 0.85 with a sensitivity of 92% and specificity of 71%, and an area under the curve (AUC) of 0.88. In comparison, a cut-off value of 40% for the extent of DCE resulted in a sensitivity of 75% and a specificity of 65%, and an AUC of 0.75 (p = 0.02 vs PTI).
Conclusions: This study shows that assessment of myocardial viability shortly after reperfused AMI is feasible with PET, and that the PTI is a good prognostic indicator for recovery of contractile function when compared to DCE-CMR.
Author Disclosures: S.A. Timmer: None. P.F. Teunissen: None. I. Danad: None. L.F. Robbers: None. P. Raijmakers: None. A.M. Beek: None. A.C. van Rossum: None. A.A. Lammertsma: None. N. van Royen: None. P. Knaapen: None.
- © 2014 by American Heart Association, Inc.