[Treatment strategies for pediatric patients with primary cardiac tumors].

OBJECTIVE: To analyze the experience of treatment strategies for pediatric patients with primary cardiac tumors. METHODS: The clinical data of 27 patients with primary cardiac tumors which detected by echocardiography from May 1999 to May 2009 was analyzed retrospectively. There were 20 male and 7 female patients, aged from 24 d to 12.6 years. There were 59.2% less than 1 year old at the time of diagnosis. A single tumor were present in 22 cases and multiple in 5 cases. Surgery was performed for 22 patients due to the varied significant symptoms such as arrhythmia, pericardial effusion, swoon and congestive heart failure with dyspnoea. Five patients were discharged hospital without surgical treatment. The surgical approaches were adopted according to tumor location. Complete surgical resection was performed in 14 patients and partial resection in 8 patients. Seven patients were underwent valve reconstruction, 5 involving the mitral valve and 2 involving the tricuspid valve. RESULTS: Histologic examination of the surgically resected tumors showed rhabdomyomas in 8 cases, fibromas in 5 cases, hemangiomas 3 cases, myxomas in 4 cases, fibrosarcoma in 1 case and yolk sac sarcoma in 1 case. Sixteen cases revealed stable haemodynamic status postoperative. Two cases occurred apparent symptoms of low cardiac output and significant arrhythmias, finally recovery after comprehensive treatment of restoration the heart function. There was a total of 4 patients in-hospital death following surgery due to multiorgan system failure. Of the 18 patients who survived after the surgery were followed up from 1 to 10 years, echocardiography showed the residual mass of the tumor with partial resection, rhabdomyoma diminishing in 2 patients and almost vanishing in 1 patient. The residual mass of one fibrosarcoma patient and one hemangioma patient were not increased. Patients with myxomas had no recur or systemic embolisation after the initial surgery. Five nonsurgical patients were followed up from 1 to 3 years, 2 patients without haemodynamic alterations, 1 patients with giant tumor of left ventricular free wall was died of arrhythmia, the other one was alive; the patient of multiple cardiac tumor with low cardiac output was died of heart failure. CONCLUSIONS: Despite the benign histology of most paediatric primary cardiac tumours, there may be significant associated with morbidity and occasional mortality. Therapy strategies should be individualised: surgery is indicated in cases with significant clinical symptoms and close follow-up is necessary for asymptomatic patients. Total resection is not the only therapeutic aim. Most important is the restoration of the normal haemodynamic heart function.

Development of mechanical circulatory support devices in China.

Myocardial dysfunction leading to low cardiac output syndrome is a common clinical pathophysiological state. Currently, the use of mechanical circulatory support (MCS) is an essential aspect of the treatment of patients with cardiac failure. Several groups in China are engaged in the design and development of MCS devices. These devices can be classified as pulsatile, rotary, and total artificial heart (TAH). There are two types of pulsatile pump, which are driven by air (pneumatic). One of these pumps, the Luo-Ye pump, has been used clinically for short-term support since 1998. The other is a push-plate left ventricular device, which has a variable rate mode. Various rotary devices are classified into axial and centrifugal pumps, depending on the impeller geometry. Most rotary pumps are based on the maglev principle, and some types have been used clinically. Others are still being studied in the laboratory or in animal experiments. Furthermore, certain types of total implantable pump, such as the UJS-III axial pump and the UJS-IV aortic valvo-pump, have been developed. Only one type of TAH has been developed in China. The main constituents of this artificial heart are two axial pumps, two reservoir tanks mimicking the right and left atria, flow meters, two pressure gauges, and a resistance adaptor. Although the development of mechanical assist devices in China is still in a nascent stage, a number of different types of MCS devices are currently being studied.

Use of the lecompte procedure for ventriculoarterial connection abnormalities in infants and children with congenital heart diseases.

BACKGROUND: The Lecompte (REV) procedure is used to correct abnormal ventriculoarterial connections in patients with congenital heart diseases; it avoids the need for an extracardiac conduit for pulmonary outflow tract reconstruction. The present study aimed to investigate effectiveness and criteria of the REV procedure in children with abnormal ventriculoarterial connections. METHODS: Thirty-eight children (mean age, (2.2 +/- 1.7) years; mean weight, (11.5 +/- 3.8) kg) with abnormal ventriculoarterial connections who had an REV procedure in our hospital from January 1998 to May 2006 were studied. Only 10 patients had the usual anteroposterior relationship of the two great arteries. The infundibular septum between the two semilunar valves was aggressively resected to enlarge it and construct a straighter left ventricular outflow tract and a wide tunnel between the ventricular septal defect (VSD) and the aorta. Eighteen cases had the original REV procedure; 20 had a modified REV procedure. RESULTS: All patients are alive; none developed severe complications. The postoperative right ventricular (RV) to left ventricular (LV) pressure ratio was 0.20-0.45. Five patients had RV dysfunction; 2 patients had a pressure gradient in the RV ventricular outlet of 30.0-34.5 mmHg; 3 cases had a 37.5-47.3 mmHg pressure difference in the RPA. All patients had an RV pressure less than half the systemic pressure. These gradients' magnitudes in all patients were consistent with the post-operative RV to LV pressure ratio (P < 0.05). During the follow-up (mean, (4.2 +/- 0.6) years), 2 patients had an RPA pressure gradient of 24.0-29.3 mmHg which abated to less than 10 mmHg after two years. CONCLUSIONS: The REV procedure provides satisfactory short- to medium-term results. It may be superior to the Rastelli procedure for treating ventriculoarterial connection abnormalities; it allows early, complete anatomic repair and reduces the need for late re-operation, since no extracardiac conduit is needed. Longer follow-up is needed to determine long-term outcomes.

Arterial switch operation with coronary arteries from a single sinus in infants.

BACKGROUND: The implantation of a coronary artery (CA) is critical for the arterial switch operation (ASO) done to treat complete transposition of the great arteries (TGA). Coronary artery abnormalities are risk factors for both early and late mortality after surgery. In this study, the methodology and effects of ASO surgery with coronary arteries from a single sinus were evaluated. METHODS AND RESULTS: From March 1999 to June 2006, 31 patients were treated with ASO with coronary arteries from a single sinus in our hospital. They aged 11 hours 16 months (2.8 +/- 3.9 months) and weighted 2.3 7.8 Kg (3.1 +/- 2.5 Kg). 27 cases had TGA and a ventricular septal defect (VSD), and 4 had TGA and an intact ventricular septum (IVS). During surgery, a CA button was implanted in the new proximal aorta with "trapdoor" technique or by inverting 90 degrees dorsally; pericardium or arterial augmentation was implanted at the base of the new major artery. The mortality rate after surgery was 25.8%. After 2-5 years of follow-up, 2 cases with residual shunting recovered spontaneously, 2 cases had residual pulmonary artery obstruction (30-56 mmHg), and none of the patients had any significant changes in myocardial ischemia. CONCLUSION: The implantation of an abnormal coronary artery is practical and feasible; it can reduce both the occurrence of twisting and deforming in the coronary artery after implantation, as well as myocardial ischemia after surgery. Thus, this could improve the surgical success and cure rates.

[Individualized surgical management of pulmonary atresia with intact ventricular septum].

OBJECTIVE: To delineate individualized surgical management strategy for the optimal management of pulmonary atresia with intact ventricular septum (PA/IVS). METHODS: Between 1997 to 2005, 52 consecutive patients with PA/IVS, 31 male and 21 female, aged 2-9, divided into 2 groups according if right ventricle-dependent coronary circulation (RVDCC) existed, underwent individualized surgical treatment. The patients in Group I (with: RVDCC, n = 6) underwent single ventricle repair. Forty-six patients were in Group II (without RVDCC), 13 of which with severe right ventricular hypoplasia (tricuspid valve Z value < -4)underwent single ventricle repair and 33 of which were with mild to moderate right ventricular hypoplasia (Z value > -4). One critical neonate underwent systemic- pulmonary artery shunt. The other 32 of the 33 patients received right ventricular decompression procedures firstly, and 6 of them presented optimal hemodynamics and oxygenation and achieved biventricular repair. If the patients presented unstable hemodynamics or hypoxemia after right ventricular decompression procedure, an additional shunt was added. 13 young infants (0-2 months) underwent additional systemic-pulmonary artery shunt, and 13 patients (> 3 months-old) underwent additional bidirectional cavopulmonary shunt (1.5 ventricular repair)The patients were followed up for 1-10 years. RESULTS: There were 1 early death in Group I and 7 early deaths in Group II. The total early mortality was 15%. A successful definitive repair was achieved in 26 cases (50%). Follow-up reported 3 late deaths. CONCLUSION: Individualized surgical management based on the presence of RVDCC, right ventricular hypoplasia grading, right ventricular growth potential, hemodynamic situation, and oxygen saturation after the decompression procedure is helpful to improve the surgical results of PA/IVS

Surgical experience of coarctation of the aorta in infants and young children.

We evaluated the effectiveness of surgical treatment for coarctation of the aorta in infants and young children, based on our experience over 7 years. From March 1999 to December 2005, 168 cases of coarctation of the aorta in patients aged 21 days to 3 years were treated by end-to-end, extended end-to-end, or extended end-to-side ascending aorta and aortic arch anastomosis. The mortality rate was 0.6%. In 138 (82%) patients, the pressure in the lower extremity was higher than in the upper extremity. During 6-24 months of follow-up, hoarseness appeared in 6 patients. Echocardiography revealed stenosis of the end-to-end anastomosis in only 2 patients. We suggest that the best option for surgical treatment of coarctation of the aorta with associated cardiac malformations is a one-stage procedure using a median sternotomy approach. It is better to perform extended end-to-end anastomosis or anastomosis between the distal descending aorta and the left wall of the ascending aorta, or to extend this anastomosis to the transverse arch.

[Analysis surgical results of 113 patients with complete transposition of the great arteries].

OBJECTIVE: To review and analysis the surgical results of 113 arteries Switch operations. METHODS: One hundred and thirteen patients had been repaired by arterial Switch operation from January 2001 to December 2005. There were 60 patients with transposition of the great arteries and intact ventricular septum (TGA/IVS), 53 patients with transposition of great arteries and ventricular septal defect (TGA/VSD). The lowest body weight was 2.3 kg, and the youngest operative age was 6 h. The arteries Switch operation was performed underwent deep hypothermic circulation arrest and low-flow perfusion. RESULTS: The total mortality was 9.7%. There were 5 deaths among TGA/IVS (8.3%), 6 deaths among TGA/VSD (11.3%). Following improvement of surgical technique, post-operative management and cardiopulmonary bypass, the operative mortality was decreased from 16.6% to 5.5%. CONCLUSIONS: The main reason for operative mortality was abnormal coronary arteries. The incidence of abnormal coronary arteries was high at TGA/VSD. The surgical results was not infected by the position of great arteries. The low cardiac output was appeared if the ratio of left ventricular pressure and right ventricular pressure less than 0.6.

Surgical treatment of persistent fifth aortic arch associated with interrupted aortic arch.

This study describes two cases of the rare congenital anomaly, persistent fifth aortic arch. Both cases involve boys (1 at 9 years of age and another at 7 months of age). To detect persistent fifth aortic arch with interrupted aortic arch, the following methods were used: echocardiogram, angiocardiography, and magnetic resonance imaging. In both cases the blood pressure between the upper and lower limbs differed. To relieve the obstruction of blood flow, each case was surgically repaired using patching or conduit interposition. Postoperative courses were uneventful. Two-year to 5-year follow-up examinations were positive showing that the anastomosis was unobstructed and the velocity of blood flow to the descending aorta was normal.

Seven years' experience of pediatric cardiopulmonary bypass: 8685 cases in Shanghai Children's Medical Center.

Herein we report our 7-year-experience of cardiopulmonary bypass. Between April 1, 1999, and December 31, 2005, 8685 children with congenital heart disease underwent cardiopulmonary bypass in Shanghai Children's Medical Center. The number of cases increased every year, and the number of patients younger than 1 year or weighing <10 kg also increased. Different bypass technology was adapted according to the operation. Roller pumps were used for most of the patients. Crystal cardioplegia (St. Thomas II) was used until blood cardioplegia was introduced in 2003. Ultrafiltrators were set up for infants weighing <10 kg. Mortality rates per year ranged from 1.81% to 3.70%. The most frequent complication was low cardiac output, about 12% in recent years. Arrhythmia, infection, and lung complications were the next three most frequent problems after surgery.

Left ventricular assist device for pediatric postcardiotomy cardiac failure.

Children with postcardiotomy heart failure who are unresponsive to maximal medical management have limited options for survival. Short-term mechanical circulatory support, such as with extracorporeal membrane oxygenation and ventricular assist devices, has assumed an expanding role in the care of these patients by providing a bridge to recovery. This report describes the use of left ventricular assist devices with centrifugal pumps in five pediatric cases (weight <15 kg) with postcardiotomy heart failure.

[Arterial switch operation for transposition of the great arteries and double outlet of right ventricle with subpulmonary ventricular septum defect].

OBJECTIVE: To summarize the clinical experience on the arterial switch operation for complex congenital heart disease in recent 3 years in our hospital. METHODS: Sixty-one patients with complex congenital heart disease received by arterial switch operation from Jan 2000 to May 2003. There were 26 patients with transposition of the great arteries and intact ventricular septum (TGA-IVS), 19 patients with transposition of the great arteries and ventricular septal defect (TGA-VSD) and 16 patients with double outlet of right ventricle with subpulmonary ventricular septum defect (Taussig-Bing). RESULTS: There were 2 death among TGA-IVS cases, 4 deaths among TGA-VSD cases and 4 deaths among Taussig-Bing cases. The total operative mortality was 16%. All patients were followed up 3 months to 3 years. In all patients, the cyanosis disappeared and the physical activities increased obviously. One patients with Taussig-Bing keep moderate mitral valve reflux unchanged, 2 patients with TGA had pulmonary and aortic supra-valve stenosis with 40 mmHg pressure gradient. One patient with subpulmonary stenosis and residual VSD was re-operated 3 months later. All survivor had good heart function. CONCLUSIONS: The effect of arterial switch operation on the treatment of TGA was well accepted in this study. The procedure used in treatment on Taussig-Bing can prevent pulmonary obstruction and avoid the complication of left ventricular outflow tract obstruction caused by intraventricular repair.

Lung perfusion with oxygenated blood during aortic clamping prevents lung injury.

To evaluate the protective effect of continuous pulmonary perfusion with oxygenated blood during aortic crossclamping, 12 mixed-breed piglets (7-12 kg) were placed on cardiopulmonary bypass for 130 minutes. An experiment group of 6 (group E) had continuous pulmonary perfusion with oxygenated blood during cardiopulmonary bypass, while the other 6 served as controls (group C). Pulmonary function was measured at the beginning and end of cardiopulmonary bypass and one hour later. Histology was compared before and after cardiopulmonary bypass. Pulmonary function after cardiopulmonary bypass was significantly better in group E than group C. There was preservation of the normal pulmonary parenchyma in group E, whereas group C had marked intra-alveolar edema and abundant intra-alveolar neutrophils. Anoxia of lung tissue during aortic crossclamping on cardiopulmonary bypass is probably the major factor in lung injury. Continuous pulmonary perfusion was effective in preventing lung injury during aortic crossclamping.

Embryonic stem cells generated by nuclear transfer of human somatic nuclei into rabbit oocytes.

To solve the problem of immune incompatibility, nuclear transplantation has been envisaged as a means to produce cells or tissues for human autologous transplantation. Here we have derived embryonic stem cells by the transfer of human somatic nuclei into rabbit oocytes. The number of blastocysts that developed from the fused nuclear transfer was comparable among nuclear donors at ages of 5, 42, 52 and 60 years, and nuclear transfer (NT) embryonic stem cells (ntES cells) were subsequently derived from each of the four age groups. These results suggest that human somatic nuclei can form ntES cells independent of the age of the donor. The derived ntES cells are human based on karyotype, isogenicity, in situ hybridization, PCR and immunocytochemistry with probes that distinguish between the various species. The ntES cells maintain the capability of sustained growth in an undifferentiated state, and form embryoid bodies, which, on further induction, give rise to cell types such as neuron and muscle, as well as mixed cell populations that express markers representative of all three germ layers. Thus, ntES cells derived from human somatic cells by NT to rabbit eggs retain phenotypes similar to those of conventional human ES cells, including the ability to undergo multilineage cellular differentiation.