24 May 18. Featured Paper
18f-fluoride positron emission tomography: computed tomography angiography predicts bioprosthetic valve degeneration.
Patients with established bioprosthetic valve dysfunction (cohort 1) were compared to patients without known dysfunction (cohort 2) and underwent serial echocardiography, contrast-enhanced CT and 18F-fluoride PET (to detect microcalcification , target-to-background ratio (TBRmean) >1.3).
In cohort 1, all patients (n=6) exhibited valve abnormalities on both CT and PET, and had the highest TBRmean values. In cohort 2 (1 month (n=9), and 2 (n=22), 5 (n=20) and 10 years (n=20) post-valve implantation), 3 subjects had bioprosthesis dysfunction on echocardiography, 13 had valve abnormalities on CT (6 calcification, 4 non-calcific leaflet thickening, 7 pannus) and 27 had increased 18F-fluoride uptake on PET. Those with CT or PET abnormalities had the most rapid valve deterioration (Figure: p=0.004 and p<0.001 respectively) while those with both CT and PET abnormalities had the fastest hemodynamic progression (Δmean gradient: 2.8 [0.44-7.3] versus -0.17 [-2.1-1.5] mmHg/year, p<0.001). 18F-Fluoride was the only independent predictor of haemodynamic progression (Figure).
18F-Fluoride PET-CT detects early bioprosthesis degeneration and predicts functional deterioration. This holds major promise to assess valve durability and to guide clinical management.