Luigi Natale MD, Abstract Co-Author: Nothing to Disclose

Alessandra Porcelli MD, Presenter: Nothing to Disclose

Antonella Lombardo MD, Abstract Co-Author: Nothing to Disclose

Agostino Meduri MD, Abstract Co-Author: Nothing to Disclose

Antonio Bernardini MD, Abstract Co-Author: Nothing to Disclose

Lorenzo Bonomo MD, Abstract Co-Author: Nothing to Disclose

To define early contrast enhanced (CE) MRI prediction of functional recovery after acute myocardial infarction

31 consecutive patients with first AMI (61+/-8 yrs., 18 anterior, 7 inferior, 18 primary PTCA, 4 thrombolysis) underwent cine- and CE-MRI within seventh day after onset. MRI was performed with a 1.5T scanner (GE Signa Excite2)as follows: cine-MRI (FIESTA) short axis from base to apex (8-10 slices); first pass imaging (FP)(FGR-ET) with iv 0.02 ml/kg Gd-DTPA, 3 ml/s) three to six short axis slices ; multi-slice (8 slices) delayed T1 imaging (DE)(IR-prepFGRE) short axis and vertical or horizontal long axis 15 min after Gd injection. Images were analyzed using a 17 segments LV model. FP and DE were scored from 0 to 4, based on transmural extension (0=normal, 1≤25%, 2≤50%, 3≤75%, 4=transmural). 527 segments were classified as: 1) normal first-pass, absent or delayed hyperenhancement 50%; 3) hypoenhancement both at first-pass and delayed imaging. Segments out of first-pass slices (total amount 961) were classified at delayed imaging as normal (=pattern 1), hyperenhanced (= pattern 2) and hypoenhanced (pattern 3). Patterns 2 and 3 were considered not predictive for functional recovery if transmural extension was larger than 50%. Four to six months follow-up MRI was performed to assess functional recovery and scar extent.

Pattern 1 was observed in 1377 segments and functional recovery was appreciated in 1259 (91%). Pattern 3 was present in only 22 segments al without recovery (100%). Pattern 2 was observed in 111 segments: 89 resulted non viable at follow up but 22 showed recovery (20%).

Pattern 1 identifies functional recovery. Pattern 3 is extremely rare and is due to large microvascular damage; furthermore its appearance depends on delay time from Gd injection. Pattern 2 is less specific, as in 25% functional recovery was demonstrated. In acute infarction pattern may represent also viable myocardium, as Gd extravasation could be increased by edema and should be carefully interpreted in the viability assessment, while in chronic infarctions it is a very accurate tool.

Natale, L, Porcelli, A, Lombardo, A, Meduri, A, Bernardini, A, Bonomo, L, Contrast-enhanced MRI Early Assessment of Myocardial Viability after Acute Myocardial Infarction.  Radiological Society of North America 2004 Scientific Assembly and Annual Meeting, November 28 - December 3, 2004 ,Chicago IL. http://archive.rsna.org/2004/4411239.html