The value of 18F-FDG PET/CT for the diagnosis of device-related infections in patients with a left ventricular assist device: a systematic review and meta-analysis.

BACKGROUND: Left ventricular assist devices (LVADs) are increasingly used for the treatment of advanced heart failure. LVADs improve quality of life and decrease mortality, but the driveline carries substantial risk for major infections. These device-related LVAD and driveline infections are difficult to diagnose with conventional imaging. We reviewed and analysed the current literature on the additive value of 18F-fluorodeoxyglucose positron emission tomography combined with computed tomography (FDG-PET/CT) imaging for the diagnosis of LVAD-related infections." MATERIALS/METHODS: We performed a systematic literature review using several databases from their inception until the 31st of December, 2019. Studies investigating the diagnostic performance of FDG-PET/CT in patients with suspected LVAD infection were retrieved. After a bias risk assessment using QUADAS-2, a study-aggregate meta-analysis was performed on a per examination-based analysis. RESULTS: A total of 10 studies were included in the systematic review, eight of which were also eligible for study-aggregate meta-analysis. For the meta-analysis, a total of 256 FDG-PET/CT scans, examining pump/pocket and/or driveline infection, were acquired in 230 patients. Pooled sensitivity of FDG-PET/CT was 0.95 (95% confidence interval (CI) 0.89-0.97) and pooled specificity was 0.91 (95% CI 0.54-0.99) for the diagnosis of device-related infection. For pump/pocket infection, sensitivity and specificity of FDG-PET/CT were 0.97 (95%CI 0.69-1.00) and 0.93 (95%CI 0.64-0.99), respectively. For driveline infection, sensitivity and specificity were 0.96 (95%CI 0.88-0.99) and 0.99 (95%CI 0.13-1.00) respectively. Significant heterogeneity existed across studies for specificity, mostly caused by differences in scan procedures. Predefined criteria for suspicion of LVAD and/or driveline infection were lacking in all included studies. CONCLUSIONS: FDG-PET/CT is a valuable tool for assessment of device-related infection in LVAD patients, with high sensitivity and high, albeit variable, specificity. Standardization of FDG-PET/CT procedures and criteria for suspected device-related LVAD infections are needed for consistent reporting of FDG-PET/CT scans.

Hemodynamic performance of stented and stentless aortic bioprostheses.

BACKGROUND: This study compares the hemodynamic performance of stented and stentless bioprostheses used for aortic valve replacement in patients with aortic stenosis and small aortic root. METHODS: Between 1995 and 1998, 37 patients with a 21-mm aortic annulus (group 1) underwent aortic valve replacement with either a 21-mm Edwards Perimount or a 23-mm St. Jude Toronto bioprosthesis whereas 47 patients with a 23-mm aortic annulus (group 2) received either a 23-mm Medtronic Mosaic or a 25-mm Edwards Prima bioprosthesis. In each group mean and peak gradients, effective orifice area index, and left ventricular mass index were compared during follow-up. RESULTS: Group 1 patients showed a significant reduction of mean (p < 0.001) and peak gradients (p = 0.001) during follow-up, more evident for St. Jude Toronto versus Edwards Perimount (p = 0.02 and p = 0.05, respectively). Group 2 patients showed a significant reduction of mean and peak gradients (p < 0.001), more evident for Edwards Prima versus Medtronic Mosaic (p < 0.001 and p = 0.07, respectively). Effective orifice area index significantly increased only in group 1 (p = 0.005). Left ventricular mass index significantly decreased in all patients regardless of the type of valve (p < 0.001). Patients with Edwards Prima showed a trend to a higher regression of left ventricular mass index versus Medtronic Mosaic recipients (p = 0.07). CONCLUSIONS: After aortic valve replacement, stented and stentless bioprostheses exhibited similar results with a more evident hemodynamic improvement during follow-up in the stentless valves. Stented bioprostheses of new generation, however, may parallel the hemodynamic performance of stentless valves and appear to be a valid alternative for aortic valve replacement in elderly patients with a small aortic annulus.

Evaluation of valve-related complications in patients with Sorin Bicarbon prosthesis: a seven-year experience.

BACKGROUND AND AIM OF THE STUDY: The study aim was to evaluate the medium-term results of aortic valve replacement (AVR), mitral valve replacement (MVR) and double valve replacement (DVR) with the Sorin Bicarbon prosthesis. METHODS: A total of 990 patients (568 men, 422 women; mean age 60+/-10 years; range: 20-86 years) was reviewed who received 1,108 Sorin Bicarbon prostheses between 1992 and 1998 at three institutions. AVR was performed in 541 patients (55%), MVR in 330 (33%) and DVR in 119 (12%). Concomitant procedures, mainly coronary artery grafting, were performed in 222 patients (22%). Follow up was 98% complete; total cumulative follow up was 3,091 patient-years. RESULTS: Hospital mortality was 3.7% (n = 37). There were 49 late deaths; actuarial survival at seven years was 88+/-2% after AVR, 86+/-5% after MVR, and 78+/-8% after DVR. At last follow up, 915 survivors were in NYHA functional class I or II. At seven years, actuarial freedom from valve-related deaths, valve thrombosis, embolism and bleeding respectively was 96+/-1%, 99+/-1%, 93+/-2% and 91+/-3% after AVR; 97+/-2%, 97+/-3%, 90+/-3% and 86+/-7% after MVR; and 92+/-6%, 98+/-1%, 64+/-2% and 82+/-2% after DVR. Reoperation was required in 20 patients (due to valve thrombosis in six, endocarditis in five and periprosthetic leak in nine). At seven years, actuarial freedom from reoperation was 97+/-1%, 96+/-2% and 84+/-9% after AVR, MVR and DVR, respectively; actuarial freedom from endocarditis was 99+/-1%, 99+/-1% and 95+/-5%. Nine patients experienced a nonstructural valve dysfunction (all periprosthetic leak), while no cases of structural failure were observed. CONCLUSION: The Sorin Bicarbon prosthesis has shown good medium-term results with regard to clinical improvement, and low incidence of valve-related complications. Thus, it appears to be a reliable valve substitute when the use of a mechanical prosthesis is indicated.