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To assess the feature of pulmonary blood flow distribution after total cavopulmonary connection (TCPC) of different types, and to provide the selection of the best type.Thirty-two consecutive survival patients after TCPC underwent radionuclide lung perfusion imaging. According to the radionuclide counts in the left and right lungs, analyses of the distribution of blood flow from superior venous cava (SVC) and inferior venous cava (IVC) and the whole pulmonary blood flow in both lungs were made. All patients were divided into 4 groups by the the anastomosis between IVC and pulmonary artery.Group I: The flow ratio of the IVC to left lung was greater than that to the right lung, Por = 0.01; the flow ratio of the SVC to right lung was greater than that to the left lung, Por = 0.01; and the whole pulmonary blood flow went dominantly to the left lung, Por = 0.05, which is not in line with physiological distribution. Group II: the flows from the SVC and IVC were mixed in the middle of the junction and ran evenly into the right and left lungs, the whole pulmonay blood flow went to both lungs, Por = 0.05. Group III: the flow ratio of the SVC to both lungs were the same, Por = 0.05, and major part from IVC went to the right lung, Por = 0.01; the pulmonary blood flow go dominantly to the right lung, Por = 0.05, which is in accord with physiological distribution. Group IV: the flows from the right SVC went to right lung by 100%, Por = 0.01, and that from the left SVC went to left lung by 100% too, Por = 0.01; the flows from IVC went dominantly to the left lung, with little part to the right lung, Por = 0.05.Different types of TCPC can result in different pulmonary blood distributions. The best flow distribution between the left and right lungs can be obtained by an offset of the IVC anastomosis toward the RPA with widening anastomosis for the patients without persist left superior venous cava (PLSVC).

The agp gene encoding ADP-glucose pyrophosphorylase is involved in cyanobacterial glycogen synthesis. By in vitro DNA recombination technology, agp deletion mutant (agp-) of cyanobacterium Synechocystis sp. PCC 6803 was constructed. This mutation led to a complete absence of glycogen biosynthesis. As compared with WT (wild type), a 60% decrease in ratio of the c-phycocyanine/chlorophyll a and no significant change in the carotenoid/chlorophyll a were observed in agp- cells. The agp- mutant had 38% less photosynthetic capacity when grown in light over 600 micromol m(-2) s(-1). Under lower light intensity, the final biomass of the mutant strain was only 1.1 times of that of the WT strain under mixotrophic condition after 6 d culture. Under higher light intensity, however, the final biomass of the WT strain under mixotrophic conditions was 3 times that of the mutant strain after 6 d culture and 1.5 times under photoautotrophic conditions. The results indicate that there is a minimum requirement for glycogen synthesis for normal growth and development in cyanobacteria.

Background A new procedure for correction of Ebstein's anomaly that restores to near normal the anatomic and physiologic function of the tricuspid valve and the right ventricle is reported. Methods Between December 1997 and September 2002, 34 consecutive patients with Ebstein's anomaly underwent this new procedure. There were 13 male and 21 female patients aged 9 months to 48 years (mean, 17 years). Tricuspid incompetence was moderate in 12 patients and severe in 22. Our repair technique is as follows: the displaced posterior leaflet with some chordae tendineae and corresponding papillary muscle are detached from the annulus and ventricular wall, respectively. The leaflet is then reattached to the native posterior annulus with reimplantation of the papillary muscle. The displaced septal leaflet is treated in the same manner. Most of the atrialized portion of the ventricular wall is excised; the tricuspid annulus is plicated. In 8 of the patients the septal leaflet was severely hypoplastic and necessitated creation of a new leaflet using autologous pericardium. Results All patients survived and recovered uneventfully. Postoperative echocardiography showed that tricuspid incompetence disappeared in 29 patients and was mild in 5. Right ventricular size decreased significantly with complete disappearance of the atrialized segment. Follow-up of patients ranged from 1 to 55 months (mean, 25 months), with 9 patients having more than 3 years of follow-up. They are doing well and their exercise tolerance improved to normal. Conclusions This new procedure anatomically corrects Ebstein's anomaly with the satisfactory early and midterm results.

Proteolytic degradation of fibrin (fibrinolysis) is mediated by plasminogen and its activators, tissue-type plasminogen activator (tPA(1)) and urokinase (uPA). Fibrinolysis is critical for preventing thrombus growth and restoring blood flow following thrombotic vascular occlusion. Plasminogen activator inhibitor-1 (PAI-1), a member of the serine protease inhibitor (serpin) superfamily, is the principal inhibitor of tPA and uPA in the fibrinolytic system. High levels of circulating PAI-1 are associated with a number of thrombotic diseases. In animal studies, transgenic mice overexpressing human PAI-1 develop spontaneous thrombosis, whereas PAI-1-deficient mice are more resistant to venous or arterial thrombosis. Furthermore, inhibition of PAI-1 activity prevents thrombus formation in animal models. The antithrombotic effects of PAI-1 inhibition are achieved by enhancing endogenous fibrinolytic activity without directly affecting blood coagulation and platelet function. Phenotypic analysis of PAI-1 deficiency in both human and mouse suggests that inhibition of PAI-1 will not lead to severe bleeding or other major adverse effects. Thus, PAI-1 inhibitors represent a new class of antithrombotic drugs with a possible wider therapeutic index than conventional antiplatelet and anticoagulant agents. This review summarizes the role of PAI-1 in thrombotic diseases and recent progress in the development of small molecule PAI-1 inhibitors.

C-type natriuretic peptide (CNP) is a member of the natriuretic peptide family that is involved in a variety of homeostatic processes. Here we characterize the processing essential for the conversion of the precursor, human pro-CNP, to the biologically active hormone. In human embryonic kidney 293 and chondrosarcoma SW 1353 cells, recombinant pro-CNP was converted into a mature peptide intracellularly as detected by Western analysis. Expression of recombinant human corin, a proatrial natriuretic peptide convertase, did not enhance the processing of pro-CNP in these cells. The processing of pro-CNP was inhibited in the presence of an inhibitor of the endoprotease furin but was not affected by inhibitors of matrix metalloproteinases and tumor necrosis factor-alpha convertase. In furin-deficient human colon adenocarcinoma LoVo cells, no conversion of recombinant pro-CNP to CNP was detected. Expression of recombinant human furin in LoVo cells restored the ability of these cells to process pro-CNP. Furthermore, incubation of purified recombinant human furin with LoVo cell lysate containing pro-CNP led to the conversion of the precursor to a mature peptide. The furin-processed CNP was shown to be biologically active in a cell-based cGMP assay. These results demonstrate that furin is a critical enzyme for the processing of human pro-CNP.

To evaluate the effects of early correction for total anomalous pulmonary venous connection (TAPVC) in infant under one.Twenty-eight infants less than one year old with TAPVC were admitted and prepared to be treated surgically from July 1995 to August 2001. Total correction was performed on 24 cases, 20 males and 4 females, aged 6.04 +/- 3.34 months, with the mean body weight of 5.74 +/- 1.22 kg, of which 10 (41.67%) being of supracardic type, 11 (45.83%) being of intracardiac type, 1 (4.17%) being of infracardiac type, and 2 (8.33%) being of mixed type. Four patients died of hypoxic attack during anteoperative preparation and failed to be operated upon.Three infants (12.5%) died within 30 days after operation. One case of intracardiac type died of circulatory failure because of severe postoperative bleeding and late exploratory thoracotomy. One case of supracardiac type died of cardiac sufficiency because of bleeding at anastomotic stoma during operation. One case of mixed type died of circulatory failure because of high pressure of left cardiac atrium. All of the 4 cases who underwent emergent operation survived. The most common complication was arrhythmia (41.67%).The early effect of early correction for TAPVC is satisfactory and its long-term effect is to be observed. A wide anastomosis between the posterior wall of the left atrium and common pulmonary vein is more important for the supracardic type. The diameters of left atrium, left ventricle and atrial septum defect have little effect on operative results. Arrhythmia after operation has no significant increase in supracardic type through. With rather high incidence rate of arrhythmia (5/8, 62.5%), the combined left atrium incision and right atrium incision approach assures a sufficiently large incision for the supracardiac type. However, this approach is statistically different in the incidence rate of arrhythmia only between supracardiac type and intracardiac type.

The agp gene encoding the ADP-glucose pyrophosphorylase is involved in cyanobacterial glycogen synthesis and glucosylglycerol formation. By in vitro DNA recombination technology, a mutant with partial deletion of agp gene in the cyanobacterium Synechocystis sp. PCC 6803 was constructed. This mutant could not synthesize glycogen or the osmoprotective substance glucosylglycerol. In the mutant cells grown in the medium containing 0.9 M NaCl for 96 h, no glucosylglycerol was detected and the total amount of sucrose was 29 times of that of in wild-type cells. Furthermore, the agp deletion mutant could tolerate up to 0.9 M salt concentration. Our results suggest that sucrose might act as a similar potent osmoprotectant as glucosylglycerol in cyanobacterium Synechocystis sp. PCC 6803.

Background Double outlet right ventricle with L-malposition of the great arteries is a rare type of double outlet right ventricle. This article reviews our experience in treating this disease surgically. Methods Between September 1995 and May 1999, 9 patients with double outlet right ventricle [S, D, L] underwent modified Rastelli procedure at Fu Wai Hospital. In all patients, the two great arteries originated completely from the right ventricle. The malformation was associated with subaortic conus and L-transposition of the great arteries. The ventricular septal defect (VSD) was subpulmonary in 3 patients, and non-committed in 6. All but one patient had either pulmonary valvular stenosis or subpulmonary stenosis. No patient had any type of palliative operation before. A right ventriculotomy was made to repair the VSD with a Dacron or vascular prosthesitic patch, and an intraventricular tunnel was made between the left ventricle and the aorta. The main pulmonary artery was divided and the proximal end was closed. A homograft conduit was implanted between the inlet of the right ventricle and the main pulmonary artery. In the Rastelli procedure, the conduit is usually positioned between the right ventricular outflow tract and the pulmonary artery. Results All patients survived and recovered uneventfully. Echocardiography demonstrated that all intraventricular tunnels and valved conduits were functioning well. The results were satisfactory. Conclusions Modified Rastelli procedure is an optimal method for surgically treating double outlet right ventricle with left-malposition of the great arteries. It can completely correct the right ventricular outflow tract stenosis, and right to left shunt, and avoid injuring the right coronary artery.

Corin is a multiple-domain type II transmembrane serine protease highly expressed in the heart. It converts pro-atrial natriuretic peptide to atrial natriuretic peptide, a cardiac hormone that regulates blood volume and pressure. Here we describe the genomic structures of the human and murine corin genes and functional analysis of their promoters. Both corin genes contain 22 exons and span >200 kb. Their intron/exon boundaries are well conserved, with most exons encoding distinct structural domains, supporting the idea that corin evolved as a result of exon duplication and rearrangement. Comparison of the 5′-flanking regions of the human and murine corin genes revealed several conserved sequences, including binding sites for TBX5, GATA, NKX2.5, and Kruppel-like transcription factors. Transfection experiments with reporter gene constructs driven by the human or murine corin 5′-flanking region indicated that the sequences from −405 to −15 in human and from −646 to −77 in mouse are sufficient to promote high levels of gene expression in murine cardiomyocytes. In contrast, these sequences produced only minimal levels of expression in HeLa cells. Within these sequences, we identified a conserved GATA element that bound to GATA-4. Mutation of the core sequence impaired both GATA-4 binding and gene expression. These data indicate that the GATA element and its binding to GATA-4 are essential for cardiac expression of the human and murine corin genes.

To describe the diagnosis and surgical management of coronary artery aneurysm.Between October 1996 and May 2000, 6 patients with coronary artery aneurysm underwent surgical treatment. Of these patients, 3 had Kawasaki disease and 3 coronary artery fistula. All patients underwent coronary artery bypass grafting. Three patients had aneurysms resected and fistulous ostium closed. One patient received aortic valve replacement.There were no deaths and later death, nor major complications during the hospital stay. The results of follow-up were satisfactory.Coronary artery aneurysm is rare and its prognosis is poor. Early diagnosis and operation are necessary. The aneurysm should be resected, the coronary artery should be bypassed, and other associated diseases should be treated properly.

To summarize the experience of surgical treatment of aorta-pulmonary window.Between January 1980 and August 2000, 18 patients suffering from aorta-pulmonary window, 11 males and 7 females, with a mean age of 6.5 years (2 approximately 14 years), underwent surgical treatment. Eleven cases were type I, 3 were type II and 4 were type III. Sixteen patients underwent surgical repair under cardiopulmonary bypass at moderate hypothermic temperatures. Deep hypothermic circulatory arrest was used in 2 of them. Closed surgical ligation under cardiopulmonary bypass at normal thermic temperature was performed on 1 case. External division and ligation under general anesthesia through left thorax was performed on 1 case. Thirteen patients underwent surgical repair through the anterior wall of aorta. Surgical repair was performed through the anterior wall of pulmonary artery in 3 cases. Other associated malformations were repaired simultaneously.Three patients died during the peri-operative period. Fifteen patients who survived the operation were followed up for 108 months on average. One patient was noted to have residue shunt on aorta pulmonary window. The other patients showed alleviation of symptoms and improvement of life quality.Early diagnosis, suitable surgical procedure and prevention and treatment of postoperative complications are the key factors for treatment of aorta pulmonary window.

To identify the clinical predictors of atrial fibrillation (AF) after coronary artery bypass grafting (CABG).322 consecutive patients who had undergone isolated CABG were reviewed. Preoperative, intraoperative and postoperative data were collected. Patients were grouped according to whether AF appeared postoperatively.AF occurred in 75 patients (23.3%). Most cases of AF (85.6%) appeared on or before the third postoperative day. The mean age for patients with AF was 62.5 years compared with 56.7 years for patients without AF (P0.05). The mean aortic crossclamp time for patients with AF was 67 min compared with 60.3 min for patients without AF (P0.05). The mean duration of cardiopulmonary bypass for patients with AF was 109.6 min compared with 97.3 min for patients without AF (P0.05). The mean duration of mechanical ventilation for patients with AF was 19.1 h compared with 15.7 h for patients without AF (P0.05). Multivariate logistic regression analysis was used to identify the following independent predictors of postoperative AF (P0.05): ageor = 65 years (OR 2.7; 95% CI 1.5 to 5.1), lesions in the right coronary artery (OR 2.5; 95% CI 1.4 to 4.5), and early postoperative withdrawal of beta blocker (OR 3.9; 95% CI 2.1 to 7.7).AF remains the most common complication after CABG. Age and lesions in the right coronary artery can influence the incidence of AF, and beta blocker and magnesium may be the most economical and effective prevention for AF early after CABG.

A 57-year-old man with a long history of frequent chest pain was admitted to our cardiac center. Four years ago, he underwent coronary artery bypass grafting (CABG) with the left internal mammary artery (LIMA) to the distal segment of the left anterior descending coronary artery (LAD) grafting for myocardial bridging (MB) in LAD despite having β-blockers and calcium channel blockers. However, the patient still had recurrent angina within 3 months after the operation. ECG showed negative T wave in leads V1 and V2. On echocardiography, left ventricular ejection fraction was 60% with normal regional wall motion. The repeat coronary angiography showed a MB in the proximal LAD about 3 cm in length with 90% systolic narrowing of the LAD, and the LIMA graft was totally occluded (Figure 1A through 1C). The …

Objective Ebstein's anomaly with isolated anterior leaflet downward displacement is rare and has not been reported in the literature to our knowledge. In this article, our experience of the surgical treatment in 6 cases with this anomaly is reported. Methods From November 2005 to November 2013, 6 patients (3 male, 3 female, aged 2-39 years) with Ebstein's anomaly and isolated anterior leaflet downward displacement received anatomic repair at the First Hospital of Tsinghua University. The diagnosis was made by echocardiography and confirmed at operation. Surgery was performed under hypothermic cardiopulmonary bypass. Surgical technique included excision of a huge atrialized portion of the right ventricle located in the anterior wall of the heart; reconstruction of the right ventricle by repairing the "V"-shaped defect left by the excision procedure; detachment, repair, and reimplantation of the anterior leaflet; and reconstitution of the right atrioventricular connection. Intraoperative transesophageal echocardiography was used to evaluate the position, morphology, structure, and function of the tricuspid valve, as well as right ventricular function. Results Five patients were discharged uneventfully, and 1 patient died of postoperative pneumonia. At follow-up from 2 months to 7 years, no notable tricuspid valve regurgitation or stenosis was found and all patients were maintaining a normal lifestyle. The 27-year-old female patient gave birth to a normal infant uneventfully 3 years after surgery. Conclusions Ebstein's anomaly with isolated anterior leaflet downward displacement is a complex and severe abnormality, and has several unique anatomic and clinical features and specific surgical requirements. Preoperative diagnosis can be made by clinical investigation and echocardiography. Excellent results can be achieved by anatomic correction.

Two kinds of autotrophic microalgae, Spirulina platensis (SP) and Chlorella protothecoides (CP) were pyrolyzed at the heating rates of 15, 40, 60 and 80 degrees C/min up to 800 degrees C in a thermogravimetric analyzer to investigate their pyrolytic characteristics. Three stages (dehydration, devolatilization and solid decomposition) appeared in the pyrolysis process. SP and CP mainly devolatilized at 190-560 degrees C and 150-540 degrees C, respectively. A total volatile yield of about 71% was achieved from each microalga. As the heating rate increased, a lateral shift to higher temperatures was observed in their thermograms, and the instantaneous maximum and average reaction rates in the devolatilization stage were increased while the activation energy was decreased. The value of activation energy for CP pyrolysis was 4.22-5.25 x 10(4), lower than that of SP (7.62-9.70 x 10(4)), and the char in final residue of CP was 14.00-15.14%, less than that of SP by 2-3%. This indicated that CP is preferable for pyrolysis over SP. The experimental results may provide useful data for the design of pyrolytic processing systems using planktonic microalgae as feedstock.

We present a minimally invasive and cosmetic approach to repair atrial septal defect. Fifty-five atrial septal defects were successfully repaired through a minimal right vertical infra-axillary thoracotomy. Every repair was performed on the beating heart with continuous suction through aortic needle vents and with the head of the patient lowered. This approach can be used not only in adults but also in young girls.

Atrial natriuretic peptide (ANP) is a cardiac hormone essential for the regulation of blood pressure. In cardiac myocytes, ANP is synthesized as a precursor, pro-ANP, that is converted to biologically active ANP by an unknown membrane-associated protease. Recently, we cloned a transmembrane serine protease, corin, that is highly expressed in the heart. In this study, we examine effects of corin on pro-ANP processing. Our results show that recombinant human corin converts pro-ANP to ANP and that the cleavage in pro-ANP by corin is highly sequence specific. Our findings suggest that corin is the long-sought pro-ANP-converting enzyme and that the corin-mediated pro-ANP activation may play a role in regulating blood pressure.

A novel cDNA has been identified from human heart that encodes an unusual mosaic serine protease, designated corin. Corin has a predicted structure of a type II transmembrane protein and contains two frizzled-like cysteine-rich motifs, seven low density lipoprotein receptor repeats, a macrophage scavenger receptor-like domain, and a trypsin-like protease domain in the extracellular region. Northern analysis showed that corin mRNA was highly expressed in the human heart. In mice, corin mRNA was detected by in situ hybridization in the cardiac myocytes of the embryonic heart as early as embryonic day (E) 9.5. By E11.5-13.5, corin mRNA was most abundant in the primary atrial septum and the trabecular ventricular compartment. Expression in the heart was maintained through the adult. In addition, mouse corin mRNA was also detected in the prehypertrophic chrondrocytes in developing bones. By fluorescent in situ hybridization analysis, the human corin gene was mapped to 4p12-13 where a congenital heart disease locus, total anomalous pulmonary venous return, had been previously localized. The unique domain structure and specific embryonic expression pattern suggest that corin may have a function in cell differentiation during development. The chromosomal localization of the human corin gene makes it an attractive candidate gene for total anomalous pulmonary venous return.

Anomalous origin of the left coronary artery from the pulmonary artery is a rare congenital cardiac malformation that is commonly associated with mitral insufficiency. Direct implantation of the anomalous origin of the left coronary artery from the pulmonary artery into the aorta is ideal, but it may not be fit for some patients whose anomalous left coronary arteries arise remotely from the ascending aorta. To solve the same technical problem in a boy with anomalous origin of the left coronary artery from the pulmonary artery in combination with moderate mitral insufficiency, we successfully elongated the anomalous coronary artery by creating a tube-shape graft using part of the pulmonary arterial wall. Simultaneous mitral annuloplasty was performed after a dual-coronary repair.

Deficiency of blood coagulation factor V or tissue factor causes the death of mouse embryos by 10.5 days of gestation, suggesting that part of the blood coagulation system is necessary for development. This function is proposed to require either generation of the serine protease thrombin and cell signaling through protease-activated receptors or an activity of tissue factor that is distinct from blood clotting. We find that murine deficiency of prothrombin clotting factor 2 (Cf2) was associated with the death of approximately 50% of Cf2 −/− embryos by embryonic day 10.5 (E10.5), and surviving embryos had characteristic defects in yolk sac vasculature. Most of the remaining Cf2 −/− embryos died by E15.5, but those surviving to E18.5 appeared normal. The rare Cf2 −/− neonates died of hemorrhage on the first postnatal day. These studies suggest that a part of the blood coagulation system is adapted to perform a developmental function. Other mouse models show that the absence of platelets or of fibrinogen does not cause fetal wastage. Therefore, the role of thrombin in development may be independent of its effects on blood coagulation and instead may involve signal transduction on cells other than platelets.

In this paper, a new-type centrifugal blood pump, whose impeller is suspended inside a pump chamber with hydraulic bearings, is presented. In order to improve the hydraulic performance of the pump, an internal flow simulation is conducted to compare the effects of different geometrical parameters of pump flow passage. Based on the numerical results, the pumps can satisfy the operation parameters and be free of hemolysis. It is noted that for the pump with a column-type supporter at its inlet, the pump head and hydraulic efficiency decreases compared to the pump with a step-type support structure. The performance drop is caused by the disturbed flow upstream impeller inlet. Further, the unfavorable flow features such as reverse flow and low velocity in the pump may increases the possibility of thrombus. It is also confirmed that the casing shape can little influence pump performance. Those results are helpful for design optimization in blood pump development.

Objectives To investigate the feasibility, advantages and results of using Left heart atrial and ventricular epicardial pacing to treat paediatric complete atrioventricular block. Methods Eight children diagnosed as complete atrioventrcular block (CAVB) ineffectively treated by drugs received implantation of left heart atrial and ventricular epicardial pacemakers. Temporal or permanent right ventricular pacing were used for all of them before implantation of left heart atrial and ventricular epicardial pacemaker. Pacemaker syndrome appeared in two of them using permanent right ventricular or right atrioventricular pacing, with EF18–25%. Heart failure appeared in one child diagnosed as acute severe myocarditis, whose EF was 47%, she firstly received temporary right ventricular pacing. Left lateral thoracotomy was performed under general anaesthesia at 4th intercostal space, two pacing leads were individually located at left atrial appendage and left ventricular lateral wall. After all the parameters were detected to be satisfactory, a pouch was made at left abdomen under coastal margin. Dual chamber pacemaker was connected with pacing leads through subcutaneous tunnels. Determine left ventricular diastolic diameters (LVDd) and EF before and after implantation of left heart atrial and ventricular epicardial pacemakers, and also during follow up. To summarise the acute and late parameters and working status for pacemaker and PR interval, QTc of electrocardiogram before and after implantation. Results (1) Left heart atrial and ventricular epicardial pacemakers were successfully implanted in all of these patients with no complications associated with surgical procedure. (2) EF of two patients with pacemaker syndrome were prominently improved after implantation (18–25% to 40–54%) and LVDd were significantly decreased (52–55 mm to 46–47 mm). EF increased from 47% to 65% 2 days after implantation for the child diagnosed as acute severe myocarditis with heart failure. (3) acute parameters: threshold for left atrium: 2.2±0.6 V, decreasing to 1.05±0.27 V (p Conclusions Implantation of left heart atrial and ventricular epicardial pacemaker should be regarded as first choice for children diagnosed as complete atrioventricular block for whom endocardial pacemaker could not be implanted. It9s advantageous for protecting heart function and avoiding pacemaker syndrome with minimal injury.

Objectives To evaluate the electrocardiographic characteristics of atrial tachycardia (AT) originating from atrial appendages in children and to investigate the effects of radiofrequency catheter ablation (RFCA) under guidance of CARTO system and appendectomy. Methods Of the 17 children with incessant AT receiving RFCA under CARTO system in our electro cardiac lab, five were diagnosed as AT originating from atrial appendages, age 8.1±4.6 (3.2∼12.8) years. Male:Female 1:4. AT appeared to be incessant in all of these five children, resisting to diverse antiarrhythmic drugs or only minimal effects were gained. Decreased cardiac systolic function were detected in four children (80%) whose left ventricular ejection fraction (LVEF) were 44%∼50%. Electroanatomical mapping under CARTO system revealed atrial appendage origin for these five children, RFCA by cooled tip catheter (Navi-Star THERMO COOL) were performed at the location of earliest AT origin. We investigated the P′ wave configurations in electrocardiogram of this AT type and effects of RFCA. Appendectomy was used for patients with AT recurrence after RFCA, and effects of this surgical procedure were evaluated. Results Increased focal automaticity was regarded as electro physiologic mechanism for AT originating from atrial appendages proved by CARTO mapping. Three from right atrial appendage (RAA) and two from left atrial appendage (LAA). P′ wave configuration for AT from RAA: (1) positive P′wave in I and aVL leads; (2) positive P′ wave in II, III and aVF leads; (3) negative and double-peak P′ wave in V1 lead. P′ wave configuration for AT from LAA: (1) negative P′ wave in I and aVL leads; (2) positive P9 wave in II, III and aVF leads (3) positive P′ wave in V1 lead (1 case) or bidirectional P′ wave with positive tendency (1 case). Immediate success rate for RFCA was 100%. three recurred (60%) during follow-up (5–14 months). Of these recurred, two originated from RAA (2/3, 66.7%) and one from LAA (1/2, 50%). Appendectomies were performed under general anaesthesia with beating heart, reversions to sinus rhythm were gained at time the appendages were incised. No recurrence was detected during 5–14 months9 follow-up. Conclusions (1) The electrocardiographic characteristics of AT originating from atrial appendages in children are unique. (2) RFCA under CARTO mapping system by cooled tip cather is safe and effective for AT originating from atrial appendages in children while recurrence rate is high. (3) Appendectomy for AT originating from atrial appendage is reliable, while the assurance of AT origin by CARTO mapping system should be gained preoperatively.

Objective To summarise and analyse the clinical experience in the use of skeletonised bilateral internal mammary artery in combination with right gastroepiploic artery in coronary artery bypass grafting. Methods A retrospective review was made to 112 patients underwent Off- Pump Coronary Artery Bypass Grafting since January 2007 to may 2009. The patients were 79 men and 33 women, with a mean age of 67 years (range 42–81 years). Result Used 112 skeletonised LIMA, with or without sequential grafting, in-situ BIMA, GEA and RA were used in 81(72%), 104(93%) and 59(53%) patients respectively. The mean number of distal anastomoses per patient was 3.43(range 2–5), Compssite Y or T graft was constructed in 41 patients, Sequential anatomoses was performed in 34 patients, Aortic no touch technique was used in 53 patients. There was no hospital mortality, no the perioperative myocardial infarction and sternal wound complication. Conclusion Skeletonized BIMA in combination with the GEA is a very versatile situ conduit to achieve complete arterial revascularization. The only constraindications for the use of BIMA and GEA grafts were emergency operations with haemodynamic instability.

P92 Atrial natriuretic peptide (ANP) is a cardiac hormone that reduces high blood pressure by promoting salt excretion, decreasing blood volume and relaxing vessel tension. It is implicated in major cardiovascular diseases such as hypertension and congestive heart failure. In cardiomyocytes, ANP is synthesized as a precursor, pro-ANP, that is converted to biologically active ANP by an unknown membrane-associated serine protease. Recently, we cloned a novel cardiac serine protease, corin, that has the predicted structure of a type II transmembrane protein. Northern and in situ hybridization detected corin mRNA in the heart where its expression was most abundant in cardiomyocytes of the atrium. Corin mRNA was also detected in developing kidney and bones. The overall expression pattern of corin mRNA was very similar to that of ANP, leading to our hypothesis that corin is the pro-ANP convertase. To test this hypothesis, we constructed expression vectors for both human corin and pro-ANP. Recombinant corin and pro-ANP were expressed in human 293 cells. Effects of corin on pro-ANP processing was examined by western analysis. The results showed that human corin, but not control proteases prothrombin and hepsin, converted pro-ANP to ANP in the cell-based experiments. To determine sequence specificity of corin-mediated cleavage in pro-ANP, we constructed a mutant pro-ANP R98G in which the predicted cleave site residue Arg98 was replaced with a Gly. In co-transfection experiments, corin processed wild-type pro-ANP but not mutant pro-ANP R98G, indicating that corin-mediated cleavage in pro-ANP is highly sequence specific. We also examined effects of protease inhibitors on processing of pro-ANP by corin. Our results showed that the activity of corin was inhibited by aprotinin, benzamidine and leupeptin but not soybean trypsin inhibitor. Similar effects of these proteases on pro-ANP processing were reported previously. Thus, corin matches all known characteristics of the long-sought pro-ANP convertase. Identification of corin as the pro-ANP convertase suggests a new regulatory mechanism for the ANP-mediated pathway that is important for controlling blood pressure.

Thrombin is a serine protease that acts as a procoagulant by clotting fibrinogen and activating platelets and as an anticoagulant by activating protein C in a thrombomodulin-dependent reaction. Fibrinogen and thrombomodulin bind competitively to an anion-binding exosite on thrombin. We prepared recombinant normal human thrombin and mutant thrombins with single amino acid substitutions in order to localize and distinguish the fibrinogen- and thrombomodulin-binding sites. Normal and mutant thrombins had similar amidolytic activity. Thrombin K52E had approximately 2.5-fold increased protein C-activating activity but only approximately 17% of normal fibrinogen-clotting activity. Thrombin R70E had normal fibrinogen-clotting activity but only approximately 7% of normal protein C-activating activity. Thrombin R68E had markedly reduced activity in both assays. Decreased activation of protein C correlated with decreased binding affinity for thrombomodulin, and ability to activate platelets correlated directly with fibrinogen-clotting activity. These results demonstrate that thrombins with predominantly anticoagulant or procoagulant activity can be created by mutagenesis and that thrombomodulin- and fibrinogen-binding sites on thrombin may overlap but are not identical.

In order to examine the possibilities of carrier detection and prenatal diagnosis in hemophilia A and B in the Chinese region of Suzhou, we analyzed four different RFLPs within the factor IX gene and two intragenic RFLPs and one extragenic RFLP for the factor VIII gene. The results obtained show important differences between the Chinese and Caucasian populations. No polymorphism was found within the factor IX gene in the Chinese population and the informativity obtained for the factor VIII gene was quite different between the two populations for each RFLP studied.