24 May 18. Featured Paper

18f-fluoride positron emission tomography: computed tomography angiography predicts bioprosthetic valve degeneration.

Link to paper on Journal of American College of Cardiology

Authors

Timothy Cartlidge, Audrey White, Edwin Van Beek, David Newby, Marc Dweck

Abstract

Purpose

We hypothesised that ¹⁸F-fluoride positron emission tomography (PET) and computed tomography (CT) could detect bioprosthetic valve degeneration before functional deterioration was apparent.

Methods

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 (TBR_mean) >1.3).

Results

In cohort 1, all patients (n=6) exhibited valve abnormalities on both CT and PET, and had the highest TBR_mean 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).

Conclusion

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.