Fusion of bone marrow-derived stem cells with cardiomyocytes in a heterologous in vitro model.

OBJECTIVE: Recent studies have demonstrated that transplanted bone marrow-derived stem cells (BMCs) possess a broad differentiation potential and are able to form new cardiomyocytes. However, the identity of BMCs as true cardiomyocytes is still ambiguous. Therefore, we investigated the fate of transplanted fluorescence labeled BMCs and cardiomyocytes in co-culture. METHODS: For cell tracking we used two different fluorescent probes, Vybrant/DiO and Vybrant/DiI. BMCs were taken from human sternal marrow, purified using a Ficoll-gradient-centrifugation, treated with 5-azacytidine and stained with Vybrant/DiO. Furthermore, isolated spontaneous beating cardiomyocytes of neonatal rats (CM) were labeled with Vybrant/DiI. Thereafter, the BMCs were transplanted into CM-cultures and investigated on day 1, 4, 7, 14 and 28 using two-color fluorescence phenotyping by laser-scanning-cytometry (LSC). Two-color positive cells were harvested by patch-clamp technique and beta-MHC mRNA expression was analyzed by single-cell PCR. RESULTS: Two different morphological phenotypes were observed by LSC. First, isolated DiO labeled BMCs without contact or with direct cell contact to DiI labeled CMs. Second, some BMCs and CMs were double positive for DiO/DiI spontaneously forming hybrids. This population increased by 18% from day 1 to 4 and decreased only slightly until day 28. Additionally, few two-color positive cell formations expressed both human and rat specific beta-MHC mRNA as well as only human beta-MHC mRNA indicating that cell-fusion and transdifferentiation has occurred. CONCLUSION: These observations provide in vitro evidence for spontaneous cell fusion and transdifferentiation of BMCs in co-culture, raising the possibility that the observed phenomenons may contribute to development or maintenance of these cell types.     

Basiskoronarchirurgie

Indications, procedural concepts and technical details of the coronary artery bypass graft (CABG) operation are continuously reassessed by cardiac surgeons and cardiologists. In particular, CABG in patients presenting with complex coronary artery disease is continuously challenged by interventional cardiology. However, considering current comparative studies, CABG remains the first line therapy for patients presenting with coronary three-vessel disease and/or left main stem stenosis. This is even more important for severely diseased coronary arteries or in complex lesions. However, cardiac surgeons now more than ever before need a profound knowledge of their own and the cardiologists’ work scope to be a strong partner in heart team discussions and a reliable guardian of the patient. The current educational paper aims at presenting important and well accepted aspects of coronary artery bypass surgery. Technical aspects as well as updated study results on early and late patient outcome will be discussed.     

VIPER-2: a prospective, randomized single-center comparison of 2 different closure devices with a hemostatic wound dressing for closure of femoral artery access sites.

PURPOSE: To report the outcome of a prospective randomized safety and performance trial of 2 access site closure devices versus a wound dressing. METHODS: Between October 2005 and July 2006, 852 consecutive patients (605 men; mean age 67 years) undergoing diagnostic or interventional catheterization procedures thru a 5- or 6-F femoral sheath were randomized to one of the 3 closure methods: a collagen plug device (Angio-Seal), a clip (StarClose), or a wound dressing (D-Stat Dry). The efficacy of the devices was assessed, as well as the complications occurring at the puncture site during the hospital stay. The primary endpoint of the study was the cumulative incidence of access site pseudoaneurysm, major access site bleeding requiring transfusion, access site vascular surgery, or death from all causes. RESULTS: There were no significant differences in baseline characteristics between the 3 treatment groups. The primary endpoint was reached in 20 (7.1%) of 281 patients treated with D-Stat Dry and in 11 (1.9%) of 571 patients treated with the mechanical closure devices (p<0.0001). There was no significant difference among the mechanical closure devices concerning the incidence of the primary endpoint (Angio-Seal 1.1% versus StarClose 2.8%; p = 0.13). CONCLUSION: The collagen plug device had the lowest rates of major and minor access site-related complications after removal of 5- or 6-F femoral sheaths. The difference between the mechanical closure devices concerning the incidence of the primary endpoint did not reach statistical significance. The wound dressing showed significantly higher major and minor complication rates.     

Family characteristics and smoking among urban and rural adolescents living in China

BACKGROUND: Adolescent smoking is a public health concern in China. Although the family is an important social influence in China, few associations among family characteristics and adolescent smoking have been examined using Chinese samples. METHODS: Survey data on psychosocial variables and smoking were collected from a sample of 3629 7th grade adolescents (46% female; 54% male; mean age 12.7 years) in Wuhan, China. For adolescents, past 30-day smoking, family relationships, parents' negative sanctioning of smoking, parents' agreement with smoking, and parents' smoking behaviors are assessed. To account for the clustered data structure, hierarchical logistic regression analyses controlling for demographics (urbanization, age) examined the independent and multivariate effects of family characteristics for each gender. RESULTS: Girls are less likely than boys to report smoking and are more likely to report positive family relationships, and having parents with negative attitudes toward them smoking. Positive family relationships and age were strongly associated with smoking for both genders. No significant differences exist by gender. CONCLUSION: These findings suggest that the quality of family relationships are important for adolescent female and male smoking in China.     

Direkte transatriale Implantation einer ICD-Sonde via rechtsseitiger anterolateraler Thorakotomie - Eine Alternative bei Thrombose der V. cava superior

Zusammenfassung Wir berichten über eine alternative Methode zum Einbringen einer transvenösen ICD-Elektrode bei einem Patienten mit Thrombose der Vena cava superior. Die Sonde wurde über eine rechtsseitige anterolaterale Minithorakotomie nach Eröffnung des Pericards direkt über das rechte Herzohr positioniert. Summary We present the case of a 52-years old patient, in whom an implantable cardioverter/defibrillator (ICD) had to be implanted in 1996 for reason of recurrent ventricular tachycardia. The patient developed an infection of the system, which therefore needed to be explanted. The attempt to replace a transvenous system a few days later was not successful, because there was a complete thrombosis (clinical asymptomatic) of the central venous system, including the superior vena cava. We then placed the lead directly via the right atrium performing a small anterior right-sided thoracotomy through the 4^th intercostal space. The device was placed subpectoral on the right side and functioned as well as a left sided device. This procedure seems us to be less harmful than the alternative of placing epicardial patches.     

Eight-year follow-up after prospectively randomized implantation of different mechanical aortic valves

Objective  The aim of this prospectively randomized study was to evaluate the hemodynamic and functional outcomes after aortic valve replacement with three different bileaflet mechanical valves. Methods  From March 1996 to August 1998, 300 consecutive patients were randomly assigned to receive ATS (n = 100), Carbomedics (n = 100), or St Jude Medical Hemodynamic Plus (n = 100) mechanical aortic valve replacement. There were no significant differences regarding patient age (61 ± 8 years), gender, NYHA, aortic valve pathology, ventricular morphology, ejection fraction and requirement for additional procedures at implant. Mean follow-up extends to 95 ± 21 months at a total of 2,891 patients years and is in 95.3% complete. Results  Implanted valve sizes were comparable at 24 ± 2 mm (ATS), 23.7 ± 1.6 mm (CM), and 23.6 ± 1.9 mm (SJMHP) (NS). Follow-up results were: transvalvular flow velocities 2.3/2.3/2.2 m/s, ejection fraction 64/59/63%, trivial transvalvular incompetence 3/3/2; paravalvular leak 2/3/2; freedom of reoperation 100/99/99%, NYHA functional status 1.5/1.8/1.6, overall survival 86.4/82.8/80.6%, freedom from thrombembolic events 100/96/98%, freedom from hemorrhage 100/100/99%, freedom from all valve related events was 100/96/98%; respectively (NS). There were no episodes of endocarditis. Ninety-four percent of the patients were satisfied with the procedure enjoying an enhanced daily life activity. Conclusions  There are no clinically relevant differences among the tested bileaflet aortic valves. Regardless of valve type, there was a rather low complication rate in this relatively young population. All three bileaflet prostheses are well suited for aortic valve replacement.     

Die Bedeutung der SYNTAX-Studie für die moderne Koronarchirurgie

Coronary artery bypass graft surgery (CABG) is still considered to be the standard of care for patients with a prognostically relevant pattern of coronary artery disease. New stent designs, including drug-eluting stents (DES) and improvements in percutaneous coronary intervention (PCI) technologies during recent years, challenge CABG in the treatment of coronary three-vessel disease and/or left main stem stenosis. To date, randomized trials have demonstrated significantly higher repeat revascularization rates in PCI patients but comparable results regarding procedural and mid-term survival as well as adverse events like myocardial infarction. In contrast, real world registry data demonstrated a survival benefit of CABG over PCI as the primary treatment option. Recently, 2-year results of the largest comparative randomized trial to date, the SYNTAX trial, were made available. These data demonstrated the superiority of CABG over PCI regarding the combined endpoint of death and major adverse cardiac and cerebrovascular events, including repeat revascularization. There were comparable results in patients with less complex coronary artery disease between PCI and CABG, while patients with more complex coronary pathologies had significantly better results after surgical intervention. These results have led to controversies in all major medical societies and have resulted in intensive and ongoing guideline discussions.