CD34 is a cell surface marker, which is expressed in various somatic stem/progenitor cells such as bone marrow (BM)-derived hematopoietic stem cells and endothelial progenitor cells (EPCs), skeletal muscle satellite cells, epithelial hair follicle stem cells, and adipose tissue mesenchymal stem cells. CD34+ cells in BM and peripheral blood are known as a rich source of EPCs; therefore, therapeutic application of BM-derived CD34+ cells has been attempted for vascular regeneration in cardiovascular diseases. Preclinical and early clinical studies of BM or granulocyte colony-stimulating factor (GCSF)-mobilized CD34+ cell therapy revealed promising outcomes with regard to safety, feasibility, and potential efficacy in critical limb ischemia (CLI) by atherosclerosis obliterans or Buerger’s disease, acute myocardial infarction, chronic myocardial ischemia (refractory angina), and dilated cardiomyopathy. Our research group is now preparing for a phase III clinical trial of CD34+ cell therapy in CLI on the basis of previous phase I/II and phase II trials.
Recently, CD34+ cell therapy has also been applied to non-healing fractures and decompensated liver cirrhosis, in which reduced blood supply is a key factor associated with disease progression. Both preclinical and pilot clinical investigations indicated the safety, feasibility, and effectiveness of GCSF-mobilized CD34+ cell therapy in these non-cardiovascular diseases. This review provides an overview of the preclinical and clinical reports to demonstrate the usefulness, current limitations, and future prospects of cell-based therapy in various types of diseases.

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For severe heart failure because of congenital heart disease, coronary artery disease, and dilated cardiomyopathy, heart transplantation is the definitive treatment approach for patients. However, a lack of donor organs remains a longstanding and serious problem worldwide. Artificial hearts, such as left ventricular assist devices, present problems related to thromboembolism, infection, gastrointestinal bleeding, and finite durability. Direct injection of isolated skeletal myoblasts and bone marrow-derived cells or cardiac stem cells has already been used clinically as a method to improve heart function by regenerating the myocardium and blood vessels. However, direct injection of the dissociated cells has shown to be slightly effective, and it is often difficult to control the form, dimensions or position of implanted cells. In an attempt to solve these problems, research has been initiated on reconstructing functional three-dimensional cardiac grafts using tissue engineering methods as a treatment for the next generation. Cell sheet transplantation has already been shown to be able to cure damaged hearts. In addition to cardiac patches transplanted directly onto damaged hearts, the next challenge is to fabricate organ-like tissues, such as tubular or spherical structures that are able to function as a cardiac pump with the potential for circulatory support.

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Cyanosis is a blue or purple discoloration of the skin or mucous membranes, which occurs when the level of deoxyhemoglobin in capillary blood is higher than 5 g/dL or when there is a high level of abnormal hemoglobin, such as methemoglobin. As the presence of cyanosis is dependent on various factors, it does not always indicate hypoxia. The recognition and appropriate management of multisystem disorders caused by long-standing cyanosis are needed in patients with cyanotic congenital heart disease or Eisenmenger’s syndrome.

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Objective: Between 2004 and 2011 in our institution, we performed the Norwood operation (NW) with bidirectional Glenn shunt (BDG) for patients with hypoplastic left heart syndrome (HLHS) at 3 months old following bilateral pulmonary artery banding (BPAB). Since 2012, we have been performsaing NW with a right ventricular-pulmonary shunt (RV–PA shunt) 1 month after BPAB in HLHS patients. The aim of this study was to evaluate the efficacy of a rapid two-stage NW operation.
Methods: Between January 2004 and December 2013, a total of 28 HLHS patients underwent NW. NW with BDG was performed in 22 patients (Group G) and NW with an RV–PA shunt was performed in 6 patients (Group S). Surgical results were compared between the groups.
Results: In Group G, 8 patients (36.3％) required pulmonary artery plasty and 20 patients (91.0％) underwent catheter intervention for pulmonary artery (PTPA). Postoperative complications comprised 3 in-hospital deaths, 2 BDG take-downs, and 1 cerebrovascular infarction. In Group S, no patients required either pulmonary artery plasty or PTPA, and BDG was performed at a median age of 7 months (range, 6–13 months). Postoperative pressure in the superior vena cava (SVC) was significantly lower in Group S.
Conclusions: NW with an RV–PA shunt 1 month after BPAB enabled avoidance of PTPA and maintenance of a low SVC pressure following BDG, and was thought to improve surgical outcomes.

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Background: Congenital heart defects have been an important cause for death among low birth weight (LBW) infants. Corrective surgery is not always a favorable solution for these fragile babies, and surgeons may choose palliative surgery, which is technically demanding. We reviewed our 10 years of experience and the outcome of initial pulmonary artery banding (PAB) without cardiopulmonary bypass (CPB) in LBW infants.
Patients and methods: Eleven infants (age, 6～78 days; body weight, 1.1～2.5 kg) underwent initial PAB without CPB (9 cases of main PAB and 2 cases of branch PAB).
Results: One patient died from a non-cardiac event. Nine patients successfully underwent the second-stage operation, at a mean weight of 4.6 kg, and eight completed the final stage. One patient experienced ventricular volume overload after main PAB. The mean Pp/Ps (pulmonary systemic blood pressure ratio) was 0.54 and the circumference of the band for the main PAB was body weight (kg)＋18.2 mm, which was a little tighter than Trusler’s rule. The circumference for the branch PAB was body weight (kg)＋8.0 mm. Of the patients who weighed less than 2 kg, all five gained body weight, and four of them successfully reached the final stage.
Conclusion: PAB in LBW infants resulted in fair clinical outcomes with acceptable morbidity and mortality. However, there is a need for specific guidance, based on accumulated experience, for the procedure and management.

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Background: Left atrioventricular valve regurgitation (LAVVR) is the main indication for reoperation in patients after repair of complete atrioventricular septal defects (CAVSD). In order to prevent postoperative LAVVR, we use a ventricular septal defect (VSD) patch for CAVSD repair of width 31.1* BSA^0.56 (i.e., equal to the normal tricuspid valve annular diameter)＋4 mm.
Methods: We evaluated the surgical outcome in 27 patients with CAVSD who underwent surgical repair at our institution between January 1995 and December 2011.
Results: The maximum follow-up duration after surgical correction was 18.5 years (median, 8.2 years). One early death (due to pulmonary embolism) and one late death (due to idiopathic pulmonary vein stenosis) occurred after the surgery. At discharge, 24 patients had less than moderate LAVVR and 2 patients had moderate LAVVR. Left atrioventricular valve stenosis was not observed. At mid-term follow-up, 23 patients had less than moderate LAVVR and 3 patients had moderate LAVVR. There was no case of severe LAVVR, and cardiac function was preserved in all patients. Only 1 patient required reoperation for LAVVR although valve replacement was not necessary. Freedom from reoperation was 96.2％ at 5, 10, and 15 years.
Conclusion: Standardizing the patch width (normal tricuspid valve annular size＋4 mm) led to good intermediate to long-term results in patients with CAVSD.

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Background: The major causes of death in patients with trisomy 18 are heart failure, pulmonary hemorrhage because of congenital heart disease (CHD), and sudden death because of apnea.
Methods: Pulmonary artery banding (PAB) and open lung biopsy for pulmonary arterial hypertension were performed in 19 patients with trisomy 18 and CHD. The pathological findings in the small pulmonary arteries and the patients’ clinical course were analyzed.
Results: The mean age of the patients at the time of open lung biopsy was 40.8±13.0 days. Four patients (21.1％) had medial defects of the small pulmonary arteries and seven patients (36.8％) had hypoplasia of the small pulmonary arteries. Twelve patients (63.2％) had alveolar hypoplasia. The prevalence of these defects was higher in patients with trisomy 18 than in previously reported patients without trisomy 18. Eleven patients (57.8％) had associated convulsions. Overall, 14 (82.4％) of 17 patients who had been weaned from ventilatory support had obstructive apnea. Six patients died, one from sudden death, two from status epilepticus, and three from cardiac-related death (CRD). The correlation between the age at the time of PAB and CRD was significant (p<0.05), as was the correlation between the duration of artificial respiration and the grade of alveolar hypoplasia (p<0.01).
Conclusions: Medial defects and hypoplasia of the small pulmonary arteries, and alveolar hypoplasia were identified in relatively large number of patients with trisomy 18. In addition, many of these patients had risk factors affecting their prognosis. Our findings suggest that if parents request surgical intervention for their children with trisomy 18, the duration of artificial respiration should be kept as short as possible and palliative surgery should be performed as early as possible.

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