OBJECTIVES
After a panel process, recommendations on the use of sutureless and rapid deployment valves in aortic valve replacement were given with special respect as an alternative to stented valves.
...METHODS
Thirty-one international experts in both sutureless, rapid deployment valves and stented bioprostheses constituted the panel. After a thorough literature review, evidence-based recommendations were rated in a three-step modified Delphi approach by the experts.
RESULTS
Literature research could identify 67 clinical trials, 4 guidelines and 10 systematic reviews for detailed text analysis to obtain a total of 28 recommendations. After rating by the experts, 12 recommendations were identified and degree of consensus for each was determined. Proctoring and education are necessary for the introduction of sutureless valves on an institutional basis as well as for the individual training of surgeons. Sutureless and rapid deployment should be considered as the valve prosthesis of first choice for isolated procedures in patients with comorbidities, old age, delicate aortic wall conditions such as calcified root, porcelain aorta or prior implantation of aortic homograft and stentless valves as well as for concomitant procedures and small aortic roots to reduce cross-clamp time. Intraoperative transoesophageal echocardiography is highly recommended, and in case of right anterior thoracotomy, preoperative computer tomography is strongly recommended. Suitable annular sizes are 19–27 mm. There is a contraindication for bicuspid valves only for Type 0 and for annular abscess or destruction due to infective endocarditis. Careful but complete decalcification of the aortic root is recommended to avoid paravalvular leakage; extensive decalcification should be avoided not to create annular defects. Proximal anastomoses of concomitant coronary artery bypass grafting should be placed during a single aortic cross-clamp period or alternatively with careful side clamping. Available evidence suggests that the use of sutureless and rapid deployment valve is associated with (can translate into) reduced early complications such as prolonged ventilation, blood transfusion, atrial fibrillation, pleural effusions and renal replacement therapy, respectively, and may result in reduced intensive care unit and hospital stay in comparison with traditional valves.
CONCLUSION
The international experts recommend various benefits of sutureless and rapid deployment technology, which may represent a helpful tool in aortic valve replacement for patients requiring a biological valve. However, further evidence will be needed to reaffirm the benefit of sutureless and rapid deployment valves.
The European Society of Thoracic Surgeons (ESTS) organized a workshop dealing with lymph node staging in non-small cell lung cancer. The objective of this workshop was to develop guidelines for ...definitions and the surgical procedures of intraoperative lymph node staging, and the pathologic evaluation of resected lymph nodes in patients with non-small cell lung cancer (NSCLC). Relevant peer-reviewed publications on the subjects, the experience of the participants, and the opinion of the ESTS members contributing on line, were used to reach a consensus. Systematic nodal dissection is recommended in all cases to ensure complete resection. Lobe-specific systematic nodal dissection is acceptable for peripheral squamous T1 tumors, if hilar and interlobar nodes are negative on frozen section studies; it implies removal of, at least, three hilar and interlobar nodes and three mediastinal nodes from three stations in which the subcarinal is always included. Selected lymph node biopsies and sampling are justified to prove nodal involvement when resection is not possible. Pathologic evaluation includes all lymph nodes resected separately and those remaining in the lung specimen. Sections are done at the site of gross abnormalities. If macroscopic inspection does not detect any abnormal site, 2-mm slices of the nodes in the longitudinal plane are recommended. Routine search for micrometastases or isolated tumor cells in hematoxylin-eosin negative nodes would be desirable. Randomized controlled trials to evaluate adjuvant therapies for patients with these conditions are recommended. The adherence to these guidelines will standardize the intraoperative lymph node staging and pathologic evaluation, and improve pathologic staging, which will help decide on the best adjuvant therapy.
Background: In addition to its multipotent capability, the mesenchymal stem cell (MSC) can secrete and supply a large amount of vascular endothelial growth factor (VEGF). The stromal-derived factor-1 ...alpha (SDF-1α) plays an important role in the homing of stem cells to the injured tissues of the heart. Therefore, the MSCs over-expressing SDF-1α could augment the angiogenesis pathway. Methods: In vitro, the differentiation of the MSCs into endothelial-like cells was induced by cultivation of cells in 10% foetal calf serum and 50 ng ml−1 SDF-1α or in specific inhibitors for endothelial nitrous oxide synthase (eNOS). In vivo, the rat model of myocardial infarction was established by occlusion of the left anterior descending coronary artery. Seven days following surgery, 5.0 × 109 pfu Ad-SDF-1α (adenoviral vector containing human SDF-1α gene under the control of the rous sarcoma virus (RSV) promoter), 5.0 × 106 Ad-LacZ-MSC or 5.0 × 106 Ad-SDF-MSC suspension in a 0.2-ml serum-free medium was injected into four sites in infarcted areas (0.05 ml per site). The rats receiving Ad-SDF-MSC also received the nitrous oxide (NO) synthesis inhibitor NG-nitro-l-arginine methyl ester (l-NAME) in drinking water (1 mg kg−1). The rats in the control group received the same volume of cell-free medium. Four weeks following transplantation, the heart function was assessed, and histological and molecular analyses were conducted. Results: The MSCs could differentiate into endothelial cells in the presence of SDF-1α, and the effect could be inhibited by l-NAME in vitro and in vivo. Western Blotting revealed an increased expression of VEGF, Akt and eNOS. Four weeks following transplantation, a reduced infarct size and fibrosis, greater vascular density and thicker left ventricular wall were observed in the Ad-SDF-MSC group. The measurement of haemodynamic parameters showed an improvement in the left ventricular performance in the Ad-SDF-MSC group as compared with other groups. Conclusion: The MSCs over-expressing the SDF-1α can produce effective angiogenesis, resulting in the prevention of progressive heart dysfunction after a myocardial infarction.
PDF
