Intraoperative stress in cardiac surgery: attendings versus residents.

BACKGROUND: Performing cardiac surgery is associated with stress for surgeons. We investigated stress levels of experienced surgeons and trainees during coronary artery bypass graft teaching procedures. METHODS: We assessed heart rate (HR) and sympathovagal balance (SVB) of experienced surgeons (attendings; n = 7) and residents enrolled in a training program (residents; n = 3) using a one-lead electrocardiogram during a total of 109 elective isolated coronary artery bypass graft procedures. We measured HR and SVB for baseline values at rest and at prespecified phases during the procedure in the role as primary surgeons (n = 10) and assistants (n = 9). RESULTS: All participants were healthy men with a mean age of 41.4 ± 4.3 y. For patients operated on during this study, demographic and intraoperative data were homogeneous. Compared with rest, mean HR and SVB for the whole procedure were higher for surgeons and assistants, with significant differences for HR values (surgeons, 83.7 ± 8.8 beats/min [bpm]; assistants, 85.4 ± 12.7 bpm, P < 0.05 versus 62.3 ± 5.1 bpm). Courses of HR and SVB were comparable for attending and resident groups but values were higher throughout for attendings compared with residents in their role as surgeons during the total procedure, and as assistants during cardiopulmonary bypass. Mean HR and SVB values of attendings assisting the procedure were higher compared with those of residents performing the operation. CONCLUSIONS: Surgical experience is not associated with reduced stress levels. Supervising a teaching case in cardiac surgery can be linked with more stress compared with the resident performing the procedure.

The influence of cardiovascular risk factors on bone marrow mesenchymal stromal cell fitness.

BACKGROUND AIMS: In the past, cell transplantation strategies for the treatment of heart failure have shown promising results in experimental and clinical studies. Bone marrow (BM)-derived stem cells represent the most frequently used cell population. Within this heterogeneous cell population, mesenchymal stromal cells (MSC) have been identified to induce therapeutic effects, mainly through paracrine mechanisms. Because of their low frequency in native tissues, in vitro cell culture expansion is mandatory prior to transplantation. We sought to identify patient-specific cardiovascular risk factors influencing the proliferative potential of MSC. METHODS: BM aspirates from 51 patients undergoing elective cardiac surgery were analyzed for MSC frequency and cell culture expansion potential. Fibroblastic colony-forming units (CFU-F) were quantified for culture conditions applying autologous (AS) or fetal bovine serum (FBS) and different basic media. Univariate and multivariate analyzes were performed in order to determine the impact of patient-specific factors on CFU-F numbers. RESULTS: Expanded MSC showed a specific immune phenotype and displayed adipogenic, chondrogeneic and osteogeneic differentiation potential. CFU-F numbers did not differ under AS or FBS supplementation. Elevated numbers of mononuclear cells, diabetes mellitus, steroid treatment, chronic obstructive pulmonary disease, renal failure, high euroSCORE and impaired left ventricular function were significant determinants for higher CFU-F numbers. CONCLUSIONS: The impact of specific cardiovascular risk factors on MSC fitness could be determined. These results may help to establish patient profiling in order to identify patients suitable for autologous MSC transplantation, and might lead to the identification of disease-related mechanisms of stem cell activation.