Abstract: Coronary artery bypass grafting (CABG) has become more and more popular, but how to decrease the thrombotic stenosis of saphenous vein grafts remains a tough problem clinically. Some researchers raised that aspirin resistance (AR) may be one of the most principal causes of graft thrombus and many correlative studies have been reported in recent years．In this article, we reviewed and analyzed the concept and evaluation criterion, incidence rate, mechanisms, clinic significance, and preventing strategy of AR, expecting to deepen the understanding of AR and help to optimize the antiplatelet therapy for postCABG patients with AR.
The bone marrow mononuclear cell（BMMNC） subset comprises mesenchymal stem cells, hematopoietic stem cells, endothelial progenitor cells. These cells can differentiate into cardiomyocytes, vascular endothelial cells and smooth muscle cells, and they can also release a wide array of cytokines that exert their effects on surrounding cells, including inducing neovascularization, preventing apoptosis of home cells and homing of endogenous systemic repairing cells. Many trials have been developed to evaluate the effect of bone marrow mononuclear cell transplantation in treating ischemia heart diseases in this country and others. Several routes have been used to deliver these cells to human myocardium or to the coronary circulation in these trials, such as intracoronary injection, intravenous infusion, direct injection into the ventricular wall, or transepicardial/transendocardial infusions，and the cells are constructed into fragmented cell sheets to improve cell retention, or some cytokines are used to enhance therapeutic effect. Although the results of the recent clinical trials in this area are rather conflicting, these therapeutic approaches seem to be promising forthe treatment of ischemic heart disease. In this review, many aspects of bone marrow mononuclear cell transplantation in myocardial infarction are summarized such as the mechanism, delivery routes, retaining of cells, homing, survival and future development, etc.
Magneticaly labeled stem cells and magnetic resonance imaging(MRI) technology is an effective tracking method in vivo study, which has high spatial-temporal resolution. Gadolinium, which shows positive T1 signals and iron oxide showing negative T2 signals are the two often used contrast agents. The latter also include superparamagnetic iron oxide particle and ultrasmall superparamagnetic iron oxide particle. Transfection agents, e.g. poly-L-lysine and protamine sulfate，can enhance magnetical nanoparticles labeling stem cells. The biological characteristics of labeled stem cells did not seem to be altered. MRI can detect the labeled stem cells’ signals and also can track changes of signal in intensity and size with time past. In conclusion, MRI tracking magneticaly labeled stem cells represents a method for noninvasivly monitoring the existence and migration of engrafts.
Abstract： Compared with mitral valve replacement, there areseveral advantages in mitral valvuloplasty, so recently more and more sights are caught on mitral valve repair. According to different etiology, the surgeon can apply annuloplasty, triangular resection, quadrangular resection, replacement or transposition of chordae tendineae and so on to treat mitral regurgitation(MR). With the development of minimally invasive surgical technology, robotic mitral valve reconstruction evolve rapidly and percutaneous interventional therapy also commence from lab to bedside.We believe surgeons can repair MR safely and successfully in the majority of patients with proficiency in the basic techniques.