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Background: The feasibility of synchrotron radiation-based phase-contrast computed tomography (PCCT) for visualization of the atrioventricular (AV) conduction axis in human whole heart specimens was tested using four postmortem structurally normal newborn hearts obtained at autopsy., Methods: A PCCT imaging system at the beamline BL20B2 in a SPring-8 synchrotron radiation facility was used. The PCCT imaging of the conduction system was performed with "virtual" slicing of the three-dimensional reconstructed images. For histological verification, specimens were cut into planes similar to the PCCT images, then cut into 5-μm serial sections and stained with Masson's trichrome., Results: In PCCT images of all four of the whole hearts of newborns, the AV conduction axis was distinguished as a low-density structure, which was serially traceable from the compact node to the penetrating bundle within the central fibrous body, and to the branching bundle into the left and right bundle branches. This was verified by histological serial sectioning., Conclusion: This is the first demonstration that visualization of the AV conduction axis within human whole heart specimens is feasible with PCCT., (© The Author(s) 2016.)

Mycotic aneurysm secondary to vertebral spondylitis is a rare but life-threatening pathology with high mortality and morbidity. The authors describe a successfully treated case of mycotic aneurysm of the common iliac artery complicated with vertebral spondylitis in a 74-year-old man. Under midline laparotomy, complete debridement of the infected tissues, in-situ replacement of the common iliac artery with cryopreserved aortic allograft, and iliac bone autotransplantation and omentopexy to fill the debrided cavity were performed. The postoperative course was uneventful, and he remains well 3 years after his operation without persistent infection or allograft rejection.

To determine the permissible range of the St. Jude Medical 19 mm valve (SJM19) as an aortic prosthesis, transvalvular maximal pressure gradient (maxPG) and postoperative reduction of left ventricular (LV) hypertrophy were examined in 21 patients (body surface area [BSA] 1.28-1.56 m2, mean 1.42 m2). Doppler echocardiographically measured maxPG at rest was 31 +/- 16 mmHg, which showed no significant difference from the differences in patients' diseases (aortic regurgitation = AR or stenosis = AS), or BSA. The maxPG, also measured during dobutamine administration when they were less than 40 mmHg at rest, increased significantly from 21 +/- 11 mmHg to 32.1 +/- 15 mmHg, having no differences from the differences in diseases or BSA. Reduction of LV hypertrophy was achieved postoperatively (mean postoperative period of ten months), with the reduction rates of 26 +/- 19% in LV mass and 21 +/- 15% in LV cross-sectional area. No significant differences were found between the reduction rates and the differences in the patients' diseases or BSA. These results indicate that, following the implantation of SJM19, LV hypertrophy was reduced in patients with AR as well as with AS, when their BSA values were less than 1.6 m2. However, limited use is recommended because the increase in pressure gradient during exercise cannot be ignored.

The authors manufactured an experimental catheter to obtain blood flow rate, measuring not only the flow velocity but also the vessel diameter. This catheter consists of 3F Doppler and 7F external sheath catheters, and four thin wires 3 cm in length are attached to the catheters at both tips at a 90 degrees pitch. After the insertion of the catheter into the vessel, vessel diameter is calculated from the maximal width of the wires, which are expanded to a spindle shape inside the vessel; the maximal width is corrected with calibration metal markers also attached at the proximal site of the external sheath catheter. The flow velocity of the blood is calculated with the FFT (Fast Fourier Transform) analyzer. In experimental circuits as well as in the canine aorta, wires were adequately expanded, and the catheter was placed at the center of the tube or the aorta. The blood flow rate, which was calculated as a product of flow velocity and vessel diameter, was well correlated to that from the electromagnetic flowmeter, not only in the experimental circuits, but also in the canine aorta.