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We report our experience with using integrated molecular and anatomic hybrid imaging to assess infection in patients who have a left-ventricular-assist device (LVAD). Methods: Thirteen 99m Tc-exametazime-leukocyte planar and SPECT/CT scans were obtained for 8 consecutive patients who had an implanted LVAD. SPECT/CT was used to assess suspected device-related infections (n 5 8) and to evaluate the efficiency of current antibiotic therapy (n 5 5). Results: Device-related infection was seen on 8 of the 13 scans. SPECT/CT was positive for infection in all 8 patients, whereas planar scans were positive in 6 of 8. SPECT/CT provided relevant information on the extent of infection and its exact location in all patients. Additional distant infectious foci were demonstrated in 3 of 13 patients. Conclusion: SPECT/CT led to an accurate diagnosis of LVAD-related infection, revealing both anatomic location and extent. This noninvasive approach could lead to improved therapeutic strategies. Impl antation of a left-ventricular-assist device (LVAD) is increasingly becoming a therapy of choice in patients with advanced heart failure (1). However, device-related infection continues to be a morbid problem and remains a serious limitation to long-term use of the device (2). Major clinical issues include diagnosing the infection early, determining the location and extent of the infection, and assessing treatment efficacy. Anatomic imaging modalities such as CT and MRI are of limited value because of the presence of metallic CT artifacts and MRI contraindications.Leukocyte planar scintigraphy is indicated for the diagnosis of infection in various clinical settings (3,4) and has a documented high sensitivity (98%) and specificity (89%) for identifying vascular graft infection (4,5). However, the poor spatial resolution of planar scintigraphy and the lack of anatomic landmarks are limiting factors. Integrated SPECT/CT allows coregistration of functional and anatomic imaging (6) and has been successfully proposed for the assessment of infectious processes in patients prone to metallic artifacts, especially in the field of bone and joint infection (7,8). However, not enough data are available on patients with soft-tissue infection (9). This study reports our early experience with radiolabeled leukocyte SPECT/CT in patients with an LVAD and suspected ongoing infectious inflammatory processes. MATERIALS AND METHODS PatientsBetween February 2007 and September 2008, 13 imaging procedures were performed on 8 consecutive men (mean age 6 SD, 56 6 11 y) who had an implanted LVAD. The mean duration that the device was in use was 666 d (range, 188-868 d). Patients were referred for leukocyte scintigraphy if device-related infection was suspected or to assess the outcome of antibiotic therapy. Five patients underwent 2 imaging procedures. Bacteriologic samples were taken from all patients (repeated blood cultures and local sample collection at the cable exit site). All patients were implanted with a HeartMate II (Thoratec) metallic rotary blood pump...

A standardized and physiologic approach to aortic valve repair, considering both the aorta (root remodeling) and the valve (resuspension of the cusp effective height and subvalvular ring annuloplasty) improved the preliminary results and might affect their long-term durability. The ongoing Conservative Aortic Valve Surgery for Aortic Insufficiency and Aneurysm of the Aortic Root (CAVIAAR) trial will compare this strategy to mechanical valve replacement.

Percutaneous heart valve implantation is feasible in inoperable patients with end-stage AS leading to hemodynamic and clinical improvement. Continued advances and improved patient selection should decrease adverse events in the near future.