Joanna Śliwka

Human Cardiac Mesenchymal Stromal Cells with CD105+CD34- Phenotype Enhance the Function of Post-Infarction Heart in Mice

Aims The aim of the present study was to isolate mesenchymal stromal cells (MSC) with CD105+CD34- phenotype from human hearts, and to investigate their therapeutic potential in a mouse model of hindlimb ischemia and myocardial infarction (MI). The study aimed also to investigate the feasibility of xenogeneic MSCs implantation. Methods and Results MSC isolated from human hearts were multipotent cells. Separation of MSC with CD105+CD34- phenotype limited the heterogeneity of the originally isolated cell population. MSC secreted a number of anti-inflammatory and proangiogenic cytokines (mainly IL-6, IL-8, and GRO). Human MSC were transplanted into C57Bl/6NCrl mice. Using the mouse model of hindlimb ischemia it was shown that human MSC treated mice demonstrated a higher capillary density 14 days after injury. It was also presented that MSC administrated into the ischemic muscle facilitated fast wound healing (functional recovery by ischemic limb). MSC transplanted into an infarcted myocardium reduced the post-infarction scar, fibrosis, and increased the number of blood vessels both in the border area, and within the post-infarction scar. The improvement of left ventricular ejection fraction was also observed. Conclusion In two murine models (hindlimb ischemia and MI) we did not observe the xenotransplant rejection. Indeed, we have shown that human cardiac mesenchymal stromal cells with CD105+CD34- phenotype exhibit therapeutic potential. It seems that M2 macrophages are essential for healing and repair of the post-infarcted heart.

Aortic cusp extension valvuloplasty: repair with an extracellular patch.

Introduction The proportion of valve repair procedures is increasing in experienced centers. The aim of the study was to assess the clinical and echocardiographic outcomes after aortic valve reconstruction with a novel surgical technique. Material and methods The study group consisted of 30 patients (23 male and 7 female) at a mean age of 35 ± 14 years. In patients with aortic root aneurysm the reimplantation or Florida sleeve technique was used. A sub-commissural annuloplasty, plication of the free edge of the cusp, shaving, and commissurotomy were performed. At this stage of surgery aortic repair was then attempted by cusp extension. Since 2013 the strips have been tailored from extracellular matrix. Results The mean aortic cross-clamp time was 90 ± 32 min. The mean cardiopulmonary bypass time was 126 ± 38 min. There was no in-hospital death. Re-exploration for bleeding was required in 1 patient. During follow-up, 1 patient needed reoperation at 1 year due to endocarditis. All patients remained alive in New York Heart Association (NYHA) functional class I. The echocardiographic findings remained unchanged in all cases during follow-up. Conclusions Our modification of aortic valve repair results in a good outcome.

First Polish analysis of the treatment of advanced heart failure in children with the use of BerlinHeart EXCOR mechanical circulatory support

BACKGROUND The treatment of advanced heart failure (HF) in children and infants poses a serious management problem. Heart failure in that patient group is usually of congenital aetiology. The treatment schedules for paediatric patients are in most cases adapted from the guidelines for treatment of adults. Up to 2009, the treatment of that extremely difficult group of patients was limited to pharmacological therapy and occasional heart transplantations. Constantly increasing problems with recruiting donors, especially for the paediatric group, contribute to the fact that mechanical support with the use of ventricular assist devices is for many children the only chance of surviving the period of waiting for a heart donor. AIM The aim of the study was to analyse the outcomes of circulatory support in Poland and to assess the advisability of this method for treatment of children with severe HF. METHODS This treatment of paediatric patients is currently used in three Polish centres. From December 28, 2009 to August 1, 2015, 27 implantations of BerlinHeart EXCOR® mechanical circulatory support system were performed in children aged from one month to 16 years (10 patients below one year of age; 37%). Left ventricular assist devices were implanted to 21 patients, whereas the remaining children received biventricular support. The most common reason for using this method was HF developed in the course of cardiomyopathy. In one case, HF after Fontan operation was the indication. RESULTS The duration of the circulatory support period ranged from six to 1215 days. It was followed by successful heart transplantations in 10 (37%) patients, in five (18.1%) it resulted in regeneration of the heart, enabling explantation of the device, whereas three children are still waiting for transplantations. Nine (33%) children died during the therapy because of thromboembolic complications. CONCLUSIONS As follows from our data, circulatory support utilising the BerlinHeart EXCOR® system is an effective and promising method used as a bridge to cardiac transplantation, or for regeneration of the myocardium in paediatric patients. In the group of the youngest and the most difficult patients, the method requires close cooperation of the medical and nursing personnel.

Graft vasculopathy in a Wistar rat model of heterotopic heart transplantation depending on gender matching between donors and recipients

Introduction Heart transplant is an accepted treatment modality in end-stage heart failure. The graft coronary artery vasculopathy is a main concern to explain the heterogeneity of the rejection process according to the gender of the donor and recipient. Aim To assess the severity and type of mechanisms leading to failure of the graft. Material and methods Experimental allogenic heart transplantation in the abdomen was performed on Wistar rats depending on the gender of the donor and recipient (F – female; M – male) in four groups (FF, FM, MM MF). The donor heart was implanted in the abdominal cavity of the recipient. Complete time of observation was 10 weeks. Bromodeoxyuridine was administered intraperitoneally to detect proliferating cells. Results There was 42.5% graft survival in all experiments. The mean time of graft survival was 60 ±18, 54 ±29, 58 ±23 and 64 ±18 days (FF, FM, MM and MF) and no significant difference was found in graft survival time among the four experimental groups (p = 0.73). None of the heart weight changes reached statistical significance. Conclusions The use of an animal experimental model helps to understand the mechanisms leading to graft failure and to compare the changes that occur in rats to human hearts. The gender matching affects the survival of the transplanted heart and severity of the graft vasculopathy.

State-of-the-art of transcatheter treatment of aortic valve stenosis and the overview of the inflow project aiming at developing the first Polish TAVI system

Initial experience of transcatheter aortic valve implantation (TAVI) or replacement (TAVR) has ap-peared as a promising minimally invasive technology for patients disqualified from surgical treatment (SAVR). Safety and efficacy of TAVI has been analyzed and assessed through numerous registries and trials. Furthermore, results obtained from comparative TAVI vs. SAVR trials proved that both treat¬ments can be considered equal in terms of post-procedural mortality and morbidity in high-risk, as well as lower risk patients. However, there are still some issues that have to be addressed, such as higher chance of paravalvular leakage, vascular injuries, conduction disturbances, malpositioning and the yet unmet problem of insufficient biological valves durability. Recent technological developments along with the learning curve of operators prove a great potential for improvement of TAVI and a chance of surpassing SAVR in various groups of patients in the near future. In pursuit of finding new solutions, the CardValve Consortium consisting of leading scientific and research institutions in Poland has been created. Under the name of InFlow and financial support from the National Center for Research and Development, they have started a project with the aim to design, create and implement into clinical practice the first, Polish, low-profile TAVI valve system, utilizing not only biological but also artificial, polymeric-based prosthesis. This review focuses on current developments in TAVI technologies including the InFlow project.

Temporary left ventricular assistance for extreme postoperative heart failure in two infants with Bland-White-Garland syndrome

Anomalous origin of the left coronary artery from the pulmonary artery (Bland-White-Garland syndrome – BWG) is a serious congenital cardiac anomaly leading to myocardial ischemia with severe heart failure. Immediate surgical correction is the treatment of choice, and the risk of postoperative complications depends on the degree of myocardial injury. The authors present two cases of infants with BWG, in whom long-term (175 and 26 days) left ventricular assistance with a Berlin Heart device was used, resulting in successful weaning from the support and subsequent hospital discharge. Because of serious hemorrhagic complications and their neurological consequences observed in the first patient, the anticoagulation protocol was modified in the second patient, providing more stable support and allowing the device to be removed after a shorter period of time. The Berlin Heart left ventricular assist device may be treated not only as a bridge for transplantation but also, considering the shortage of donors in this age group, as a bridge to recovery.