Morpho-metabolic post-surgical patterns of non-infected prosthetic heart valves by [18F]FDG PET/CTA: "normality" is a possible diagnosis.

AIMS: To define characteristic PET/CTA patterns of FDG uptake and anatomic changes following prosthetic heart valves (PVs) implantation over time, to help not to misdiagnose post-operative inflammation and avoid false-positive cases. METHODS AND RESULTS: Prospective evaluation of 37 post-operative patients without suspected infection that underwent serial cardiac PET/CTA examinations at 1, 6, and 12 months after surgery, in which metabolic features (FDG uptake distribution pattern and intensity) and anatomic changes were evaluated. Standardized uptake values (SUVs) were obtained and a new measure, the valve uptake index (VUI), (SUVmax-SUVmean)/SUVmax, was tested to homogenize SUV results.In total, 111 PET/CTA scans were performed in 37 patients (19 aortic and 18 mitral valves). FDG uptake was visually detectable in 79.3% of patients and showed a diffuse, homogeneous distribution pattern in 93%. Quantitative analysis yielded a mean maximum standardized uptake value (SUVmax) of 4.46 ± 1.50 and VUI of 0.35 ± 0.10. There were no significant differences in FDG distribution or uptake values between 1, 6, or 12 months. No abnormal anatomic changes or endocarditis lesions were detected in any patient during follow-up. CONCLUSIONS: FDG uptake, often seen in recently implanted PVs, shows a characteristic pattern of post-operative inflammation and, in the absence of associated anatomic lesions, could be considered a normal finding. These features remain stable for at least 1 year after surgery, so questioning the recommended 3-month safety period. A new measure, the VUI, can be useful for evaluating the FDG distribution pattern.

Effect of bioprostheses anti-calcification treatment: comparative follow-up between Mitroflow LX and Magna pericardial xenografts using a propensity score-weighted analysis.

Objectives: The efficacy of anti-calcification treatment of bioprosthetic heart valves remains unclear. The aim of this study was to compare the clinical outcomes between Mitroflow LX valve, without anti-calcification treatment, and the Carpentier-Edwards Perimount Magna (P-Magna), with anti-calcification treatment. Methods: Between 2005 and 2012, 625 consecutive patients underwent aortic valve replacement either with a Mitroflow LX ( n = 329) or a P-Magna ( n = 296). Variables regarding patient-related risk factors and operative data were accounted for an inverse probability of treatment weighting analysis. Then, adjusted survival outcomes and the rate of structural valve disease (SVD) were assessed for each group. Results: Mean follow-up times were 4.1 ± 2.29 years and 3.9 ± 2.63 years, respectively ( P = 0.34). Adjusted overall survival rate was higher in the P-Magna group than in the Mitroflow LX group at 8 years (69.1% vs 51.9%, respectively) [HR = 1.44, 95% CI: 1.01 to 2.06; P = 0.0467]. Similarly, the 8-year cardiac-related survival rate was also higher in the P-Magna group [HR = 1.99, 95% CI: 1.19 to 3.32; P = 0.0083]. One patient (0.8%) with P-Magna and 23 patients (18.5%) with Mitroflow LX group developed SVD (0.24% per patient-year vs 4.5% per patient-year, respectively; P < 0.001). At 5 and 8 years, valve-related survival rates did not differ significantly between both groups [HR = 1.67, 95% CI: 0.95 to 2.95; P = 0.075]. Conclusions: The P-Magna prosthesis showed significantly better overall and cardiac-related survival than the Mitroflow LX. The higher early SVD and reoperation rates seen with the Mitroflow LX prosthesis did not impact negatively on valve-related survival.