Coronary artery assessment by multidetector computed tomography in patients with prosthetic heart valves

Objectives

Patients with prosthetic heart valves may require assessment for coronary artery disease. We assessed whether valve artefacts hamper coronary artery assessment by multidetector CT.

Methods

ECG-gated or -triggered CT angiograms were selected from our PACS archive based on the presence of prosthetic heart valves. The best systolic and diastolic axial reconstructions were selected for coronary assessment. Each present coronary segment was scored for the presence of valve-related artefacts prohibiting coronary artery assessment. Scoring was performed in consensus by two observers.

Results

Eighty-two CT angiograms were performed on a 64-slice (n?=?27) or 256-slice (n?=?55) multidetector CT. Eighty-nine valves and five annuloplasty rings were present. Forty-three out of 1160 (3.7%) present coronary artery segments were non-diagnostic due to valve artefacts (14/82 patients). Valve artefacts were located in right coronary artery (15/43; 35%), left anterior descending artery (2/43; 5%), circumflex artery (14/43; 32%) and marginal obtuse (12/43; 28%) segments. All cobalt-chrome containing valves caused artefacts prohibiting coronary assessment. Biological and titanium-containing valves did not cause artefacts except for three specific valve types.

Conclusions

Most commonly implanted prosthetic heart valves do not hamper coronary assessment on multidetector CT. Cobalt-chrome containing prosthetic heart valves preclude complete coronary artery assessment because of severe valve artefacts.

Key Points

? Most commonly implanted prosthetic heart valves do not hamper coronary artery assessment ? Prosthetic heart valve composition determines the occurrence of prosthetic heart valve-related artefacts ? Bj?rk–Shiley and Sorin tilting disc valves preclude diagnostic coronary artery segment assessment     

Hope for male fecundity: clinically insignificant changes in semen parameters over 10 years at a single clinic while assessing an infertility population

Journal of Assisted Reproduction and Genetics - What is the trend in sperm parameters in a group of men attending a single reproductive center, over a 10-year period? A retrospective study was...     

Cardiac computed tomography angiography results in diagnostic and therapeutic change in prosthetic heart valve endocarditis

Echocardiography may miss prosthetic heart valve (PHV) endocarditis which advocates for novel imaging techniques to improve diagnostic accuracy and patient outcome. The purpose of this study was to determine the complementary diagnostic value of cardiac computed tomography angiography (CTA) to the clinical routine workup including transthoracic and transesophageal echocardiography (TTE/TEE) in patients with suspected PHV endocarditis and its impact on patient treatment. A diagnostic prospective cross-sectional study was chosen as design. Besides clinical routine workup (including TTE/TEE), CTA was performed to assess its diagnostic accuracy and complementary diagnostic/therapeutic value. For the diagnostic accuracy, the reference standard was surgical findings or clinical follow-up. To determine the complementary diagnostic/therapeutic value an expert-panel was used as reference standard. Twenty-eight patients were included. CTA resulted in a major diagnostic change in six patients (21 %) mainly driven by novel detection of mycotic aneurysms by CTA. Furthermore, treatment changes occurred in seven patients (25 %) compared to clinical routine workup. Diagnostic accuracy of routine clinical workup plus CTA was superior to clinical routine workup alone for the detection of PHV endocarditis in general, vegetations and peri-annular extension. This study demonstrates that CTA and clinical workup including TTE and TEE are complementary in patients with PHV endocarditis. Therefore, CTA imaging has to be considered after clinical routine workup in patients with a high suspicion on PHV endocarditis.     

Abnormal testicular function: potential of P-31 MR spectroscopy in diagnosis

Phosphorus-31 MR spectroscopy of the human testis was performed on healthy volunteers (n = 17) and oligospermic (n = 7) and azoospermic patients (n = 4). All patients in the latter group had the Sertoli-cell-only syndrome. Determination of the ratios of phosphomonoesters (PMs) to adenosine triphosphate (ATP), phosphodiesters (PDs) to ATP, and inorganic phosphate (Pi) to ATP made it possible to discriminate among these three groups. The testicular PM/ATP ratio was 1.71 +/- 0.03 (mean +/- standard deviation) in the healthy volunteers and dropped to 1.41 +/- 0.06 (P less than .001 in comparison with healthy volunteers) in the oligospermic patients and to 1.22 +/- 0.07 (P less than .001) in the azoospermic patients. The testicular PD/ATP ratio did show a slight increase from 0.52 +/- 0.10 in healthy volunteers to 0.68 +/- 0.09 (not significant) for oligospermic patients and to 0.83 +/- 0.10 (P less than .01) for azoospermic patients. The Pi/ATP ratio did not show significant differences between healthy volunteers (0.12 +/- 0.07) and oligospermic patients (0.23 +/- 0.08) but was elevated in the azoospermic patients (0.79 +/- 0.12) (P less than .001).     

Quantitative analysis of gene expression in human articular chondrocytes assigned for autologous implantation

Autologous chondrocyte implantation (ACI) relies on the implantation of in vitro expanded cells. The aim was to study the dedifferentiation of human articular chondrocytes under different cultivating conditions [days 0–10 in the primary culture (P0); passages in a monolayer from P0 to P3; monolayer vs. alginate and monolayer vs. alginate/agarose hydrogels] using real‐time PCR analysis. The relative gene expressions for collagen type I and II, aggrecan and versican were quantified and the corresponding differentiation indexes (Col2/Col1, Agr/Ver) were calculated. The values of both differentiation indexes decreased exponentially with time in the P0 monolayer culture, and continued with a significant decrease over the subsequent monolayer passages. On the contrary, the chondrocytes seeded in either of the hydrogels significantly increased the indexes compared to their parallel monolayer cultures. These results indicate that alginate and alginate/agarose hydrogels offer an appropriate environment for human articular chondrocytes to redifferentiate after being expanded in vitro. Therefore the three‐dimensional (3D) hydrogel chondrocyte cultures present not only surgical, but also biological advantage over the classic suspension–periosteum chondrocyte implantation. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:847–853, 2008