Ryuji Tominaga — Page 2

PubMed2002

Adaptive immunity is severely impaired by open-heart surgery.

OBJECTIVE: The influence of open-heart surgery on antigen-specific immunity, also called adaptive immunity, remains to be clarified. We explored the effects of open-heart surgery on adaptive immunity. METHODS: In 8 consecutive adult patients undergoing elective cardiac surgery with cardiopulmonary bypass, we measured the T cell-response to purified protein derivative (PPD) antigen perioperatively. We separately measured the proliferation of T cells and the antigen presentation of antigen-presenting cells (APCs) using a cross-reaction system. RESULTS: T cell response to PPD antigen was severely impaired by open-heart surgery. Compared to preoperative values, T cell response to PPD antigen fell to 5.7 +/- 4.4% immediately after surgery, 4.5 +/- 3.2% on postoperative day (POD) 1, to 22.4 +/- 24.6% on POD 3 and to 50.1 +/- 34.3% on POD 7. T cell proliferation on POD1 decreased to 29 +/- 26%. APC antigen-presentation on POD 1 also decreased to 31 +/- 36%. CONCLUSIONS: Open-heart surgery impaired both T cell proliferation and the antigen-presentation. Such synergistic impairment severely impaired adaptive immunity. This impairment was both severer and longer than we anticipated based on previous studies using the response of T cells to lectin as a marker of cell-mediated immunity.

Aged↗

PubMed2002

Extensive use of polytetrafluoroethylene artificial grafts for prolapse of bilateral mitral leaflets.

OBJECTIVES: There are an increasing number of reports concerning mitral valve repair by reconstruction of the chordae tendinae with the use of expanded polytetrafluoroethylene (PTFE) sutures. However, little information is available about the extended application or results of this technique for extended prolapse of bilateral mitral leaflets, which is considered to be difficult to repair. METHODS: Between October 1993 and May 1998, 17 patients (age range 16-74 years) who had from moderate to severe mitral regurgitation as the result of a prolapse of bilateral leaflets underwent mitral valve repair by reconstruction of artificial chordae with CV-4 expanded PTFE sutures. Either bilateral or unilateral Kay's suture annuloplasty was also performed to correct annular dilatation in all patients. RESULTS: No operative death or late mortality was observed. Before discharge, immediate postoperative echocardiography showed less than moderate mitral regurgitation in 16 of 17 patients. The follow-up was completed in all cases by a clinical examination and serial echocardiograms, and the median follow-up period was 52 months (range 27-82 months). There was one failure that required re-operation because of worsening mitral regurgitation (elongation of the anchored side of papillary muscle). When the re-operated patient was excluded from the following data, the degree of mitral regurgitation, estimated by echocardiography performed at recent follow-up, was none in four patients, trivial in eight patients, and mild in four patients. The systolic and diastolic dimensions of the left ventricle decreased significantly (P<0.01). CONCLUSIONS: Because replacement of artificial chordae was not complicated and seemed to preserve fine relationships among leaflet tissues, chordae, and papillary muscles, we therefore suggest that the extensive use of PTFE artificial chordae appears to be a promising procedure for the repair of all kinds of mitral lesions causing mitral regurgitation.

Adolescent↗