In the in vitro model of thrombolysis designed by ourselves, urokinase (500 000~ 5 000 000IU ? L-1) reduced the weight of artificial thrombi in a way of dose-dependence. At the level of 2 000 000 IU ? L-1, the action reached the peak. On the contrary, defibrase (6. 25~25 IU ? L-1) dose-relatedly increased the thrombus weight. After defibrinogenation in platelet-poor plasma by addition of porcine thrombin (100 000 IU ? L-1) , defibrase no longer increased the thrombus weight, whereas in comparison with saline, defibrase still showed no apprciable reduction in thrombus weight. The findings hinted that defibrase may have no direct thrombolytic property.

Objective To evaluate the effect of radiofrequency catheter ablation treament of supraventricular tachyarrhythmias on spontaneous attack of atrial fibrillation (AF) and to further discuss the electrophysiological mechanisms of AF. Methods Thirty-one patients (20 men, 11 women; mean age 54?12 years, age range 24-69 years) with supraventricular tachyarrhythmias coexisting with AF were included in the study. The mean history of the study group was 9?5 (range 1-19) years and the mean number of AF attack was 6?5 times (range 2-18). Of the 31 cases, 5 supraventricular tachyarrhythmias were electrophysiologically proven to be typical atrial flutter (AFL), 17 atrioventricular reentrant tachycardia (AVRT), 9 atrioventricular nodal reentrant tachycardia (AVNRT). Linear lesions to make bi-directional block were done in cavo-tricuspid isthmus in AFL patients, slow pathway modification in AVNRT and accessory pathway ablation in AVRT. Results After mean follow-up of 39?19 months (range 12-72), of the 31 patients, 23 had no occurrence of AF. In 3 of the 5 AFL patients, no AF occurred after ablation, but 2 still had AF occurrence, of whom one had frequent atrial premature contractions (APCs) and short runs of AF. In 26 patients with supraventricular tachycardia, 20 had no occurrence of AF after ablation. In the remaining 6, 2 had less frequent occurrence, and 4 remained the same, of whom one had hypertention with enlarged left atrium, and another had frequent APCs and short runs of atrial tachycardia. Conclusion AFL may share the same substrate with AF or may be the trigger factor of AF, and AVNRT and AVRT are only trigger factors of AF. So after successful ablation treatment of these tachycardias, no AF occurs. But in some cases, AF substrate still exists, and AF can be triggered by other trigger factors besides tachycardias mentioned above.

OBJECTIVETo observe the long-term outcome of implantable cardioverter-defibrillator (ICD) implantation in Brugada syndrome patients and to explore how to reduce the frequency of ICD nappropriate schocks.

METHODSThis study included 14 symptomatic patients (mean age (44.3 ± 8.3) years old; all males) with Brugada syndrome implanted with ICD in our hospital between 1998 and 2012, and these patients were followed up routinely every 6 months. The initial ICD parameters were set according o conventional experience. The ventricular tachycardia (VT) zone was programmed to ventricular rate 150-188 bpm/cycle length (CL) 400-320 ms and the ventricular fibrillation (VF) zone was programmed to ventricular rate ≥ 188 bpm/CL ≤ 320 ms. The total events were recorded by ICD. The ICD parameters revision was made by electrophysiological (EP) experts in case of inappropriate shocks.

RESULTSPatients were followed up for mean (43.0 ± 28.3) months. A total of 297 VF/VT events were recorded by ICD. Electrophysiological experts found that 90% (178/198) episodes were true VF ( CL 130-250 ms) among of 198 VF episodes and 147 VF episodes were terminated by one shock and 21 VF events were terminated by two or more shocks, and the rest 10 VF terminated spontaneously. Only 9% (9/99) VT events were true VT (CL 320-360 ms) among of 99 VT episodes. Eight VT episodes were converted by antitachycardia pacing therapy (ATP) and the other one terminated spontaneously. The rest 90 VT episodes (91%) were supraventricular arrhythmias (SVT, CL 340-390 ms). About 90% inappropriate shocks can be reduced by Wavelet discrimination function and optimal programming (VF zone ventricular rate ≥ 222 bpm/CL ≤ 270 ms and/or VT zone ventricular rate 167-222 bpm/CL 270-360 ms ) according to the characteristics of arrhythmia of individual patient.

CONCLUSIONICD can effectively prevent sudden cardiac death and syncope in high-risk patients with Brugada syndrome. The most common complication is inappropriate shock due to SVT. Optimal ICD programming with Wavelet discrimination function can effectively reduce the frequency of inappropriate shock rate.

Adult ; Brugada Syndrome ; Cardiac Conduction System Disease ; Death, Sudden, Cardiac ; Defibrillators, Implantable ; Humans ; Male ; Syncope ; Tachycardia, Ventricular ; Treatment Outcome ; Ventricular Fibrillation

Objective To study the mode and clinical implications of onset of spontaneous tosade de pointes in the congenital long QT syndrome. Methods We reviewed electrocardiograms (ECGs) of 55 patients with congenital QT syndrome for syncope. Documentation of the onset of tosade de pointes was available for 16 patients. All these patients had "definitive long QT syndrome" by accepted clinical and ECG criteria. Results One hundren and forty-nine runs of tosade de pointes were documented in 16 patients,of whom,there were 130 runs of pause-dependent tosade de pointes. Conclusion Our results show that the pause-dependent tosade de pointes,which has been recognized as a hallmark of tosade de pointes in the acquired long QT syndrome,plays a major role in the genesis of tosade de pointes in the congenital long QT syndrome.

OBJECTIVETo describe a new noncontact balloon catheter mapping system and to assess the clinical utility of this system for guiding endocardial mapping and ablation of tachycardia.

METHODSFive patients with tachycardia underwent endocardial mapping and radiofrequency ablation using the noncontact balloon catheter mapping system. A 9 French, 64-electrode balloon catheter and a conventional 7 French electrode catheter for mapping and ablation were positioned in the same ventricular chamber. Ventricular three-dimensional geometry was established by the computerized mapping system. Using a boundary element inverse solution, 3360 virtual endocardial electrograms were computerized and used to derive isopotential maps. The earliest endocardial activation site, the exit site and the activation sequence of tachycardia or the critical isthmus of the reentry circuit were identified. Radiofrequency ablation with circular or linear lesion was performed at the target sites guided by the locator system.

RESULTSSix clinical types of tachycardia, 5 of which were ventricular tachycardia and one was concealed fasciculoventricular fiber mediated tachycardia, were induced by programmed stimulation. The mean cycle length of these tachycardias was 336.6 +/- 42.69 msec. The earliest activation site and the exit site of 5 mapped tachycardias were all identified using the system. One type of ventricular tachycardia was hemodynamically unstable and difficult to terminate, and could not be mapped. Among the 6 types of tachycardias, radiofrequency ablation was successful in 4. There was no complication during and after the procedure. During the mean follow-up of 6 months, no tachycardia recurred in the patients with a successful ablation.

CONCLUSIONSThe noncontact mapping system described in this study has advantage over conventional mapping techniques for refractory tachycardia. It is not only helpful for understanding the electrophysiologic mechanism of a complex case, but also suitable for mapping hemodynamically intolerated and nonsustained ventricular tachycardia.

Adult ; Body Surface Potential Mapping ; methods ; Cardiac Catheterization ; Catheter Ablation ; methods ; Catheterization ; methods ; Humans ; Male ; Middle Aged ; Tachycardia, Ventricular ; physiopathology ; surgery

OBJECTIVE: To investigate the persistent damage of learning and memory ability after the cessation of sub-chronic manganese(Mn)-exposure in rats. METHODS: Specific pathogen free weaning male SD rats were randomly divided into control group and low-, medium-and high-dose groups based on body weight, with 6 rats in each group. Rats were intraperitoneally injected with Mn chloride(MnCl_2·4 H_2O) at the concentrations of 0, 5, 10, or 20 mg/kg body weight, 5 days per week for 6 weeks and continued to be observed for 12 weeks after the cessation of Mn-exposure. During the experiment, the body mass of the rats was weighed. Learning and memory ability was evaluated by a Morris water-maze task at the 6 th weeks of Mn-exposure(cessation of Mn-exposure of week 0), the 6 th and 12 th week of the cessation of Mn-exposure. The organ coefficients of heart, liver, spleen, kidney and testicles were evaluated after the cessation of Mn-exposure on week 12. RESULTS: The body mass of the high-dose group was lower than that of the other 3 groups(P<0.05) at the 4 th and 6 th week of Mn-exposure and the 2 nd week of the cessation of Mn-exposure. There was no significant difference in body mass between the groups(P>0.05) on the 12 th week of the cessation of Mn-exposure. The escape latency of high-dose group was higher than that of the control group(P<0.05), and the number of platform crossings in the low-, medium-and high-dose groups were fewer than that in the control group(P<0.05) after the cessation of Mn-exposure. The escape latency was shorter and the numbers of platform crossings were higher on the 6 th and 12 th week of the cessation of Mn-exposure(P<0.05) when compared with that of the 6 th week of Mn-exposure rats. There was no statistical significance in the organ coefficients of heart, liver, spleen, kidney and testicles among the 4 groups at the 12 th week of the cessation of Mn-exposure in rats(P>0.05).CONCLUSION: Sub-chronic Mn exposure can impair learning and memory ability of rats, and the damage persists after the cessation of Mn-exposure.

Globally, gynecological malignancies are common types of female cancer and the main cause of cancer death among women. Cervical cancer, endometrial cancer and ovarian cancer, which are the main types of gynecological cancers, pose a significant threat to women's health worldwide. Studies have shown that diet plays an important role in the occurrence and development of gynecological cancers such as cervical cancer, endometrial cancer, and ovarian cancer, for which added sugar may be an influencing factor due to its food source characteristic and related biological effect. However, this paper reviewed the research progress on the relationship between consumption of added sugar and gynecological cancers such as endometrial cancer, ovarian cancer and cervical cancer, with a view to providing a reference for the active prevention of gynecological cancer.