Myocardial viability with chronic total occlusion assessed by hybrid positron emission tomography/magnetic resonance imaging.

BACKGROUND

The present study was performed to compare the relationship of 18F-fluorodeoxyglucose (FDG) uptake and late gadolinium enhancement (LGE) transmurality with the improvement of left ventricular function in patients with coronary chronic total occlusion (CTO) assessed by hybrid FDG positron emission tomography (PET)/magnetic resonance imaging (MRI).

METHODS

Thirty-eight consecutive patients with CTO underwent FDG PET/MRI. Twenty-three patients then underwent percutaneous coronary intervention (PCI), and the final study population comprised 15 patients who underwent both initial and follow-up MRI. The degree of wall motion abnormality in each of the 17 myocardial segments was evaluated based on the extent of wall thickening on cine MRI using a 5-point scale.

RESULTS

Among all 646 myocardial segments at baseline, FDG uptake significantly decreased as the transmurality of LGE is advanced. Of the 15 patients who underwent PCI, 152 segments showed wall motion abnormalities at baseline. The functional recovery of the wall motion abnormality of the PET-viable/MRI-viable segments was highest, and that of the PET-nonviable/MRI-nonviable segments was lowest. There were no differences in functional recovery between the PET-viable/MRI-nonviable and PET-nonviable/MRI-viable segments.

CONCLUSION

Simultaneous assessment of FDG and LGE using a hybrid PET/MRI system can help to predict functional recovery after PCI in patients with CTO.