Fusie van cardiale CT en PET scan voor bepalen van normale glucose (suiker) opname rondom een Aorta Kunstklep

Rationale:
Prosthetic Heart Valve (PHV) endocarditis is complicated by peri-annular extension (abscesses/mycotic aneurysms) in up to 50% of patients and has an in-hospital mortality of approximately 30%. However, with current standard imaging tools such as Echocardiography and Computed Tomography Angiography (CTA), it remains difficult to detect peri-annular extension, which is an indication for urgent surgery in order to reduce mortality. Furthermore, if peri-annular abnormalities are found with imaging, differentiation between active and non-active inflammatory tissue is impossible, because of the lack of metabolic information. Hybrid imaging with combined anatomical information by CTA and metabolic information by FDG-PET may provide this additional information. However, normal baseline FDG uptake at different time points after aortic PHV implantation is unknown and obligatory for correct interpretation of CTA/PET scans in PHV patients.


Objective: To determine normal FDG-uptake around PHV’s in aortic position.


Study design: Prospective multi-centre cross-sectional study


Methods: 18-Fluorine FDG-PET is performed to assess uptake around the PHV after fusion with the CTA. FDG uptake is scored by: 1. Qualification Visual Score for Hypermetabolism (QVSH) which can be: none, mild, moderate or severe. 2. Standardized Uptake Value (SUV) ratio’s, defined as the maximum SUV value around the PHV divided by the mean SUV value in the mediastinum.


Study population: The total group consists of patients (≥ 50 years) after uncomplicated PHV implantation in aortic position (n=75). The FDG-PET/CTA imaging is performed in the early and late and chronic postoperative episode (group 1, 2 and 3 respectively):

• Early postoperative (group 1, n=25): 5 (± 1) weeks after PHV implantation .

• Late postoperative (group 2, n=25): 12 (± 2) weeks after PHV implantation .

• Chronic postoperative (group 3, n=25): 12 (± 2) months after PHV implantation.



We will only include patients in group 3 in case FDG uptake around the PHV in group 2 results in moderate or severe FDG uptake according to the QVSH score in 1 or more patients.
Of note: patients cannot be included in two groups.


Main study parameters: 18F-FDG/PET baseline uptake measured by the QVSH value and the SUV ratio’s around the PHV in early, late and possibly also in the chronic postoperative phase: 5 (± 1) weeks, 12 (± 2) weeks and 12 (± 2) months respectively.

Prosthetic Heart Valve (PHV) endocarditis is complicated by peri-annular extension (abscesses/mycotic aneurysms) in up to 50% of patients and has an in-hospital mortality of approximately 30%. However, with current standard imaging tools such as Echocardiography and Computed Tomography Angiography (CTA), it remains difficult to detect peri-annular extension, which is an indication for urgent surgery in order to reduce mortality. Furthermore, if peri-annular abnormalities are found with imaging, differentiation between active and non-active inflammatory tissue is impossible, because of the lack of metabolic information. Hybrid imaging with combined anatomical information by CTA and metabolic information by FDG-PET may provide this additional information. However, normal baseline FDG uptake at different time points after aortic PHV implantation is unknown and obligatory for correct interpretation of CTA/PET scans in PHV patients.

cross-sectional

PET-CT and CTA