Citations

SUMMARY Quantification and characterization of the hemodynamic environment created after flow diversion treatment of cerebral aneurysms is important to understand the effects of flow diverters and their interactions with the biology of the aneurysm wall and the thrombosis process that takes place subsequently. This paper describes the construction of multi‐modality image‐based subject‐specific CFD models of experimentally created aneurysms in rabbits and subsequently treated with flow diverters. Briefly, anatomical models were constructed from 3D rotational angiography images, flow conditions were derived from Doppler ultrasound measurements, stent models were created and virtually deployed, and the results were compared with in vivo digital subtraction angiography and Doppler ultrasound images. The models were capable of reproducing in vivo observations, including velocity waveforms measured in the parent artery, peak velocity values measured in the aneurysm, and flow structures observed with digital subtraction angiography before and after deployment of flow diverters. The results indicate that regions of aneurysm occlusion after flow diversion coincide with slow and smooth flow patterns, whereas regions still permeable at the time of animal sacrifice were observed in parts of the aneurysm exposed to larger flow activity, that is, higher velocities, more swirling, and more complex flow structures. Copyright © 2014 John Wiley & Sons, Ltd.

The purpose of this case is to describe the complex perioperative management of a 30-year-old woman with congenital heart disease and multiple resternotomies presenting with pulmonary homograft dysfunction and evaluation for percutaneous pulmonary valve replacement. Transvenous, transcatheter Melody valve placement caused left main coronary artery occlusion and cardiogenic shock. An Impella ventricular assist device (VAD) provided rescue therapy during operating room transport for valve removal and pulmonary homograft replacement. ECMO support was required following surgery. Several days later during an attempted ECMO wean, her hemodynamics deteriorated abruptly. Transesophageal and epicardial echocardiography identified pulmonary graft obstruction, requiring homograft revision due to large thrombosis. This case illustrates a role for Impella VAD as bridge to definitive procedure after left coronary occlusion and describes management of complex perioperative ECMO support challenges.

Mitogenic stimulation of lymphocytes involves alkalinization of intracellular pH (pHi). Subsequent pHi regulation may involve HCO3− extrusion through Cl−/HCO3− exchangers and/or Na+‐HCO3− co‐transporters with acid‐loading capability. Abnormalities in these mechanisms could result in immune dysfunctions, as suggested by the CD8+ T‐cell expansion encountered in mice lacking Ae2 (a widely expressed acid loader with electroneutral and Na+‐independent Cl−/HCO3− anion‐exchange activity). Here we report that CD8+ T cells but not CD4+ T cells or other lymphocyte populations, are crucially dependent on Ae2 for pHi regulation. While total lymphocytes (including isolated CD4+ T cells) exhibit Ae1 expression and Na+‐HCO3− co‐transport with acidifying potential, CD8+ T cells lack these acid‐loading mechanisms. In Ae2‐KO mice, CD4+ but not CD8+ T cells upregulate these potential Ae2 surrogates. As a consequence, Ae2‐KO CD8+ T cells exhibit alkalinized pHi, and dramatically increase their pHi upon CD3 stimulation. Moreover, stimulated Ae2‐deficient CD8+ T cells show enhanced intracellular production of IL‐2 and membrane expression of its receptor IL‐2Rα, together with increased cell proliferation and activation. These findings demonstrate that CD8+ T cells are critically dependent on Ae2 for pHi homeostasis and tuning of cell proliferation and activation. Ae2 thus constitutes a novel target to modulate CD8+ T‐cell responses.

We assessed the clinical results, radiographic outcomes and complications of patients undergoing total shoulder replacement (TSR) for osteoarthritis with concurrent repair of a full-thickness rotator cuff tear. Between 1996 and 2010, 45 of 932 patients (4.8%) undergoing TSR for osteoarthritis underwent rotator cuff repair. The final study group comprised 33 patients with a mean follow-up of 4.7 years (3 months to 13 years). Tears were classified into small (10), medium (14), large (9) or massive (0). On a scale of 1 to 5, pain decreased from a mean of 4.7 to 1.7 (p = < 0.0001), the mean forward elevation improved from 99° to 139° (p = < 0.0001), and the mean external rotation improved from 20° (0° to 75°) to 49° (20° to 80°) (p = < 0.0001). The improvement in elevation was greater in those with a small tear (p = 0.03). Radiographic evidence of instability developed in six patients with medium or large tears, indicating lack of rotator cuff healing. In all, six glenoid components, including one with instability, were radiologically at risk of loosening. Complications were noted in five patients, all with medium or large tears; four of these had symptomatic instability and one sustained a late peri-prosthetic fracture. Four patients (12%) required further surgery, three with instability and one with a peri-prosthetic humeral fracture.Consideration should be given to performing rotator cuff repair for stable shoulders during anatomical TSR, but reverse replacement should be considered for older, less active patients with larger tears.Cite this article: Bone Joint J 2014;96-B:224–8.

Flow diversion treatment of cerebral aneurysms has increasingly been considered, especially for large complex aneurysms with wide necks that are difficult to treat with coils of by clipping. However, the relationship between the hemodynamic environment created immediately after implantation of flow diverters (FD) and the subsequent aneurysm occlusion is poorly understood [1].

Since treatment of cerebral aneurysms with flow diverters (FD) has gained much attention in recent years, it is important to understand what is the effect of these devices on the flow through arteries jailed or crossed by these devices [1].

Objectives/Hypothesis Pharyngocutaneous fistulae (PCF) are known to occur in nearly one‐third of patients after salvage total laryngectomy (STL). PCF has severe impact on duration of admission and costs and quality of life and can even cause severe complications such as bleeding, infection and death. Many patients need further surgical procedures. The implications for functional outcome and survival are less clear. Several studies have shown that using vascularized tissue from outside the radiation field reduces the risk of PCFs following STL. This review and meta‐analysis aims to identify the evidence base to support this hypothesis. Data Sources English language literature from 2004 to 2013 Review Methods We searched the English language literature for articles published on the subject from 2004 to 2013. Results Adequate data was available to identify pooled incidence rates from seven articles. The pooled relative risk derived from 591 patients was 0.63 (95% CI: 0.47 to 0.85), indicating that patients who have flap reconstruction/reinforcement reduced their risk of PCF by one‐third. Conclusion This pooled analysis suggests that there is a clear advantage in using vascularized tissue from outside the radiation field in the laryngectomy defect. While some studies show a clear reduction in PCF rates, others suggest that the fistulae that occur are smaller and rarely need repair. Laryngoscope , 124:1848–1853, 2014