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.

Pulmonary herniation after minimally invasive cardiac surgery: review and implications from a series of 20 cases.

Minimally invasive cardiac surgery (MICS) via right lateral mini thoracotomy is the gold standard treatment approach for mitral and tricuspid valve disorders. Other selected procedures (e.g. transapical aortic valve implantation, MIDCAB) require a left lateral mini thoracotomy for surgical access. Advantages of MICS over complete sternotomy are well known, but access-related complications post MICS, such as pulmonary herniation, are often underestimated/overlooked. In males, a pulmonary herniation in the proximity of the former thoracotomy is often clinically visible, especially when the intrathoracic pressure rises (e.g. during coughing). In females, clinical symptoms may be hidden by the breast and patients often have unspecific complaints or occasional pain when coughing, making identification of a lung herniation more difficult. Chest computed tomography is the diagnostic tool of choice for pulmonary herniations. Using a series of 20 patients with pulmonary herniation post MICS, we report our findings in diagnosis and treatment of this condition.

Minimally invasive left atrial appendage (LAA) clip insertion after challenging LAA occluder implantation to minimize the risk of stroke.

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia, requiring lifelong anticoagulation or interventional, transseptal left atrial appendage (LAA) occluder implantation to minimize stroke risk. Incomplete LAA closure post implantation is a frequent observation. Incomplete LAA occlusion after transseptal occluder implantation necessitates anticoagulation in cases of persistent AF to minimze risk of embolism and/or apoplexy. Patients with contraindications to lifelong anticoagulation therapy are challenging to treat and alternative options are needed. We present a case of a patient with persistent AF who underwent frustraneous LAA occluder implantation. The patient's anatomy necessitated surgical closure of the LAA, which was accomplished with an LAA clip 4 weeks after implantation. The patient was discharged in excellent clinical status 5 days after the surgery. No further complications were observed within the following year.