Table 1 Image quality (IQ) score specified per PHV manufacturer type Type Manufacturer N = Median IQ score (minimum-maximum) General IQ score Supravalvular Perivalvular Subvalvular Valvular Carbomedics St. Jude Sorin ON-X Duromedics Medtronic Hall Björk-Shiley Sorin monoleaflet Perimount Medtronic intact Medtronic mosaic Mitroflow St. Jude Epic Freestyle 20 14 8 7 1 13 5 2 13 2 2 2 1 1 3.8 (2.5–4.0) 3.0 (2.0–4.0) 3.5 (2.5–4.0) 3.5 (3.5–4.0) 3.0 (3.0–3.0) 3.0 (2.5–4.0) 1.0 (1.0–1.0) 1.0 (1.0–1.0) 3.5 (3.0–4.0) 3.5 (3.0–4.0) 4.0 (4.0–4.0) 3.3 (3.0–3.5) 3.5 (3.5–3.5) 4.0 (4.0–4.0) Results Patient characteristics A total of 84 ECG-gated examinations of 83 patients (age 56.3 ± 14.8 years (mean ± SD), 47 men) with 91 PHVs were available. Seventy mechanical PHVs and 21 biological PHVs were evaluated. One patient, who underwent two CTs, was included twice. This patient underwent a reoperation in which different PHVs were implanted between both CTs. PHVs were positioned in the aortic (n = 71), mitral (n = 17), pulmonary (n = 1) and tricuspid position (n = 2). Seventy mechanical PHVs of 8 different manufacturers including 50 bileaflet PHVs (20 Carbomedics, 14 St Jude and 16 other PHVs) and 20 tilting disc valves (13 Medtronic Hall valves, 5 Björk-Shiley valves and 2 Sorin monoleaflet valves) were assessed. Twenty-one biological PHVs, 13 Perimount valves and eight other valves, were evaluated. 1392 Type Biological (n=21) Mechanical (n=70) Bileaflet (n=50) Tilting disc (n=20) Table 2 Image quality (IQ) score specified per PHV design type Type Bileaflet Tilting disc Biological N = 50 20 21 Median IQ score (minimum-maximum) Supravalvular 3.5 (2.0–4.0) 3.0 (1.0–4.0) 3.5 (3.0–4.0) Perivalvular 3.3 (2.0–4.0) 2.5 (1.0–4.0) 3.5 (2.0–4.0) Subvalvular 3.5 (2.0–4.0) 2.8 (1.0–4.0) 4.0 (2.5–4.0) Valvular 3.5 (1.5–4.0) 2.5 (1.0–4.0) 2.0 (1.0–4.0) General IQ score 3.5 (2.5–4.0) 2.8 (1.0–4.0) 3.0 (2.0–4.0) Eur Radiol (2011) 21:1390–1396 3.5 (2.0–4.0) 3.0 (2.0–4.0) 3.5 (2.5–4.0) 3.5 (3.5–4.0) 2.0 (2.0–2.0) 3.0 (2.0–4.0) 1.0 (1.0–1.0) 1.0 (1.0–1.0) 3.5 (3.0–4.0) 3.3 (3.0–3.5) 3.8 (3.5–4.0) 2.0 (2.0–2.0) 3.5 (3.5–3.5) 4.0 (4.0–4.0) CT parameters 3.5 (2.5–4.0) 3.0 (2.0–4.0) 3.5 (2.5–4.0) 4.0 (3.0–4.0) 2.5 (2.5–2.5) 3.5 (2.5–4.0) 1.0 (1.0–1.0) 1.0 (1.0–1.0) 4.0 (3.0–4.0) 3.3 (2.5–4.0) 3.8 (3.5–4.0) 3.5 (3.0–4.0) 3.5 (3.5–3.5) 4.0 (4.0–4.0) 3.5 (2.0–4.0) 3.0 (1.5–4.0) 4.0 (2.5–4.0) 4.0 (3.5–4.0) 3.0 (3.0–3.0) 3.0 (2.0–4.0) 1.0 (1.0–1.0) 1.0 (1.0–1.0) 2.0 (1.5–4.0) 1.5 (1.0–2.0) 2.5 (2.0–3.0) 1.8 (1.5–2.0) 1.5 (1.5–1.5) 2.0 (2.0–2.0) 3.5 (1.5–4.0) 3.0 (2.5–4.0) 3.5 (3.0–4.0) 4.0 (3.5–4.0) 2.5 (2.5–2.5) 3.0 (2.0–4.0) 1.0 (1.0–1.0) 1.0 (1.0–1.0) 3.0 (3.0–4.0) 3.0 (2.5–3.5) 3.8 (3.4–4.0) 2.5 (2.0–3.0) 3.0 (3.0–3.0) 4.0 (4.0–4.0) All patients underwent a retrospectively ECG-gated CT on a 16-slice (n = 4), 64-slice (n = 28) or 256-slice (n = 52) MDCT system (Brilliance 16, Brilliance 64 and iCT, Philips Medical Systems, Cleveland, Ohio). The indications for the CT examinations were PHV or surrounding anatomy assessment (n = 42), evaluation of aortic aneurysms or dissection (n = 22) and other cardiac and pulmonary indications (n = 20). In 38/84 (45%) of the patients the delay between surgery and CT could be inferred from the medical records. The median interval between surgery and the CT examination was 31 months (range: 0–175). Mean heart rate during CT was 58 ± 31 bpm (range 48–139). In 13 of the 83 patients (16%) the mean heart rate during CT was unknown. Sixty-six out of 84 (79%) examinations were performed as a dedicated cardiac CT (≥600 mAs) and 18/84 (21%) as an ECG-gated CT of the aorta (200–400 mAs). Fourty-two of the 66 (64%) dedicated cardiac CT exami- nations were performed assessed for diagnostic PHV