RESUMO
Objective:To evaluate the value of integrated PET/MR in assessing myocardial viability in ischemic heart disease.Methods:A total of 39 patients (28 males, 11 females; age (60.1±12.0) years) diagnosed with ischemic heart disease in Xuanwu Hospital, Capital Medical University were retrospectively enrolled from September 2020 to December 2021. All patients underwent cardiac 13N-NH 3·H 2O and 18F-FDG PET/MR examinations. Late gadolinium enhancement (LGE) sequence was included in MRI scan. PET and MRI images were analyzed and myocardial viability of each myocardial segment was evaluated according to the American Heart Association (AHA) 17 segment method. The extent of left ventricular infarcted myocardium was measured based on PET and MRI images. Weighted Kappa test was used to evaluate the agreement of PET and MRI in assessing myocardial viability. The extent of infarcted myocardium measured by PET and MRI was compared by paired- t test, and Pearson correlation analysis was used to assess the correlation between them. Results:There was a moderate agreement between PET and MRI in assessing myocardial viability ( Kappa=0.532, P<0.001), with the agreement rate of 69.83%(463/663). There was no significant difference but strong correlation between the extents of infarcted myocardium measured by PET and MRI ((23.89±14.23)% vs (23.55±11.90)%; t=-0.24, P=0.809; r=0.79, P<0.001). In segments with normal perfusion and metabolism on PET, 22.52% (100/444) showed abnormal enhancement on MRI. On the other hand, 39.89% (73/183) of the segments classified as non-viable on MRI showed normal or viable on PET. Conclusion:Integrated PET/MR is able to take full advantage of the complementary nature of PET and MRI, achieving the comprehensive and accurate evaluation of myocardial viability.