Adjuncts to transcatheter aortic valve implantation

Introduction: The appreciable rise in percutaneous valve procedures has been pursued by a wave of development in advanced technology to help guide straightforward, streamlined and safe intervention. This review article aims to highlight the adjunctive devices, tools and techniques currently used in transcatheter aortic valve implantation procedures to avoid potential pitfalls.

Areas covered: The software and devices featured here are at the forefront of technological advances, most of which are not yet in widespread use. These products have been discussed in national and international structural intervention conferences and the authors felt it important to showcase particularly well designed adjuncts that improve procedural efficacy and safety. Whilst vascular pre-closure systems are used routinely and are an integral part of these complex cardiovascular procedures, these have been well summarised elsewhere and are beyond the scope of this article.

Expert commentary: The rising volume of patients with aortic stenosis who are treatable with TAVI means that this exponential increase in procedures must be accompanied by a steady decline in procedural complications. This section provides an overview of our current perspective, and what we feel the direction of travel will be.     

Prevalence of Sarcopenia and Its Impact on Postoperative Outcome in Patients With Crohn's Disease Undergoing Bowel Resection

Background: Sarcopenia has been proposed to be a prognostic factor of outcomes for various diseases but has not been applied to Crohn's disease (CD). We aimed to assess the impact of sarcopenia on postoperative outcomes after bowel resection in patients with CD. Materials and Methods: Abdominal computed tomography images within 30 days before bowel resection in 114 patients with CD between May 2011 and March 2014 were assessed for sarcopenia as well as visceral fat areas and subcutaneous fat areas. The impact of sarcopenia on postoperative outcomes was evaluated using univariate and multivariate analyses. Results: Of 114 patients, 70 (61.4%) had sarcopenia. Patients with sarcopenia had a lower body mass index, lower preoperative levels of serum albumin, and more major complications (15.7% vs 2.3%, P = .027) compared with patients without sarcopenia. Moreover, predictors of major postoperative complications were sarcopenia (odds ratio [OR], 9.24; P = .04) and a decreased skeletal muscle index (1.11; P = .023). Preoperative enteral nutrition (OR, 0.13; P = .004) and preoperative serum albumin level >35 g/L (0.19; P = .017) were protective factors in multivariate analyses. Conclusion: The prevalence of sarcopenia is high in patients with CD requiring bowel resection. It significantly increases the risk of major postoperative complications and has clinical implications with respect to nutrition management before surgery for CD.     

Operative Effect Comparison of Flexible Drill Guiding vs. Traditional Drill Guiding Template for Lower Cervical Pedicle Screw Insertion: A Retrospective Analysis

Objective

Accurately inserting pedicle screws is the key point of posterior pedicle screw fixation for lower cervical spine (C3–C7) instability. 3D printing technology can improve the accuracy of screw placement. This study compared the safety of 3D-printed flexible drill guiding template vs. traditional rigid drill guiding template for lower cervical pedicle screw insertion.

Methods

This was a retrospective study. A total of 34 patients who underwent lower cervical pedicle screw fixation from March 2018 to May 2021 were enrolled in this study, and they were divided into the flexible drill flexible drill group and the traditional drill group. A total of 18 patients in the flexible drill flexible drill group underwent pedicle screw fixation assisted by 3D printed flexible drill guiding templates for the lower cervix, and 16 patients in the traditional drill group underwent pedicle screw fixation assisted by 3D printed regular drill guiding templates for the lower cervix. The length of the incision and intraoperative blood loss during surgery were recorded and compared for the two groups. The grade, deviation of the screw entry point, deviation of the screw medial angle and screw length were measured and compared after surgery for the two groups by independent-sample tests.

Results

There was a significant difference in the length of the incision and blood loss between the two groups (P < 0.05). There was a significant difference between the two groups for grade (P = 0.016). The deviation of the screw entry point was 0.65 ± 0.50 mm in the flexible drill group and 0.78 ± 0.83 mm in the traditional drill group. The deviation of the screw medial angle was 2.14 ± 1.78 in the flexible drill group and 4.23 ± 2.51 in the traditional drill group, with a significant difference between the two groups (P < 0.05).

Conclusion

Compared with regular guiding techniques, lower cervical pedicle screw placement assisted by multistep navigation templates and flexible K-wires results in less trauma and better safety.     

The enhancement of siPLK1 penetration across BBB and its anti glioblastoma activity in vivo by magnet and transferrin co-modified nanoparticle

In order to enhance the penetration of small interference RNA against the polo-like kinase I (siPLK1) across BBB to treat glioblastoma (GBM), transferrin (Tf) modified magnetic nanoparticle (Tf-PEG-PLL/MNP@siPLK1) was prepared. The in vitro experiments indicated that Tf-PEG-PLL/MNP@siPLK1 enhanced the cellular uptake of siPLK1, which resulted in an increase of gene silencing effect and cytotoxicity of Tf-PEG-PLL/MNP@siPLK1 on U87 cells. Besides, Tf-PEG-PLL/MNP@siPLK1 significantly inhibited the growth of U87 glioblastoma spheroids and markedly increased the BBB penetration efficiency of siPLK1 with the application of external magnetic field in in-vitro BBB model. The in vivo experiments indicated that siPLK1 selectively accumulated in the brain tissue, and markedly reduced tumor volume and prolonged the survival time of GBM-bearing mice after Tf-PEG-PLL/MNP@siPLK1 was injected to GBM-bearing mice via tail vein. The above data indicated that magnet and transferrin co-modified nanoparticle enhanced siPLK1 penetration across BBB and increased its anti GBM activity in vivo.