Clinical Electrophysiology -> SCA Risk Assessment: -> Other Noninvasive Techniques D-PO04 - Poster Session IV (ID 15) Poster


Background: Myocardial replacement fibrosis has been reported to occur in one-third of patients with mitral valve prolapse (MVP) and significant mitral regurgitation (MR). It remain unknown, however, if there are detectable changes in myocardial metabolism, suggestive of inflammation, that accompany the development of fibrosis.
Objective: To characterize the burden and distribution of 18F-fluorodeoxyglucose (18F-FDG PET) uptake (to identify active inflammation) and late gadolinium enhancement (LGE; to identify scar) in patients with degenerative MVP and ventricular ectopy.
Methods: Twenty patients with primary degenerative MVP and significant MR underwent Hybrid PET/MRI. Ventricular arrhythmias were categorized as either complex (c-VAs; n=12) or minor (m-VAs, n=8). Co-registered hybrid 18F-FDG PET and MRI LGE images were assessed and categorized.
Results: Focal, or focal-on-diffuse, uptake of 18F-FDG (PET+) was detected in 17 of 20 patients (85%). There was a trend towards a higher LGE burden in those patients with c-VAs (5.9 ± 3.9%), compared to those with m-VAs (3.3 ± 2.3%). There was less FDG uptake in the c-VA cohort, as compared to the m-VA cohort (SUVmax = 3.5 ± 1.2 vs 6.9 ± 4.2).
Conclusion: In this pilot study, we demonstrate a novel association between degenerative MVP and FDG uptake, a surrogate for myocardial inflammation. The higher LGE burden and lower FDG uptake in those with complex ventricular arrhythmias raises the intriguing possibility that ventricular arrhythmia burden may represent different stages of a progressive disease process.