Author + information
- Carlos G. Santos-Gallego,
- Torsten Vahl,
- Georg Goliasch,
- Kiyotake Ishikawa,
- Roger J. Hajjar,
- Valentin Fuster,
- Javier Sanz and
- Juan Jose Badimon
Non-invasive assessment of the area at risk (AAR) during myocardial infarction (MI) is of paramount importance in cardioprotection studies. Current cardiac magnetic resonance (CMR) methods require 2 separate scans for assessment of cardiac function (cine balanced steady-state free precession sequence – bSSFP-) and myocardial edema (T2-weighted sequence -T2W-). The aim of this study was to investigate the capabilities of bSSFP CMR as a novel approach for characterizing myocardial edema in animals after reperfused MI.
Acute MI was induced in 19 Yorkshire pigs by transient balloon occlusion of the proximal LAD. CMR was performed 1 week post MI. AAR was quantified as regions with signal intensity >2 standard deviations above that of remote myocardium in both conventional T2W and bSSFP sequences. MI size was measured by standard late gadolinium enhancement. At 1 month dobutamine-MRI was performed to assess contractile reserve; prior to euthanasia AAR was also quantified by Evans blue staining.
AAR derived from the bSSFP sequence encompassed 39.5±5.7% of left ventricular (LV) mass, and did not differ from T2W-derived AAR (40.1±5.8%; p=NS) or Evans blue-derived AAR (39.1±4.8%; p=NS). AAR detected by both bSSFP and T2W was larger than scar size (33.2±7.8% of LV, p<0.05 for both) allowing for quantification of salvaged myocardium. There was a strong correlation between bSSFP and T2W edema size both on a slice-by-slice analysis (r=0.94, p<0.01) and on a whole-heart analysis (r=0.95, p<0.01); and between bSSFP and Evans blue (r=0.93, p<0.01). The myocardial salvage derived from bSSFP correlated with parameters of post-MI LV remodeling: LVEF (r=0.71), contractile reserve (r=0.73), LVESV (r= −0.75) and LV mass at 1 month (r= −0.8, p<0.05 for all).
bSSFP cine imaging allows for simultaneous evaluation of cardiac function and edema. Importantly, bSSFP accurately quantifies AAR similar to conventional T2W-CMR and Evans blue. This new imaging approach allows evaluation of cardiac function and edema simultaneously, offering the possibility to reduce scan time and increase efficiency.
Poster Sessions, Expo North
Monday, March 11, 2013, 9:45 a.m.-10:30 a.m.
Session Title: Imaging: MRI VI – Clinical Applications and Advances in CMR
Abstract Category: 19. Imaging: MRI
Presentation Number: 1310-322
- 2013 American College of Cardiology Foundation