Death, Sudden, Cardiac ; Humans ; Reward

Objective:To prepare compound isosorbide mononitrate sustained-release capsules and study the drug release. Meth-ods:Isosorbide mononitrate pellets were prepared by the fluidized bed coating technology. The influencing factors in the preparation process were examined and the major factors were optimized by single factor experiments. The drug release was determined by HPLC. The best formula was screened by optimizing aspirin coating solution. Results:The compound isosorbide mononitrate sustained-release capsules were prepared by the best formula. Both the two drugs could achieve promising release, and in vitro release behavior of isosor-bide mononitrate was fitted Higuchi equation,which was similar to that of the imported preparations. The release of aspirin in acidic and alkaline media was in coincidence with the release requirements. Conclusion:The formula is reasonable and the preparation process is stable with promising sustained release property.

0 05) 3 hours after myocardial infarction,and remarkably decreased (P

Objective To inquire into the effects of cardiac ? 1 -adrenergic receptor on myocardial remodeling and modulating calcium channel. Methods The models of myocardial remodeling after myocardial infarction in Wistar rats were used to study the expression changes of cardiac collagen subtype Ⅰ,Ⅲ,fibronectin (FN) with immunohistochemistry,and changes of T-type calcium channel,L-type calcium channel and ? 1 -adrenergic receptor mRNA expressions by reverse transcription and polymerase chain reaction(RT-PCR) and in situ hybridization. Cardiac total Ca 2+ was tested by atomic absorption/flame emission spectrophotometer. Results Cardiac collagenⅠ,collagen Ⅲ,FN protein expressions in betaloc group were remarkably decreased (P

Objective To inquire into the correlation of cardiac AT 1 receptor,? 1 receptor with PKC/MAPKs(protein kinase C/mitogen-activated protein kinase) signal transduction pathway during myocardial remodeling.Methods Twenty-four Wistar rats were randomly divided into four groups-sham group,infarcted group,losartan group and betaloc group.Except sham group,left anterior descending coronary artery was ligated for 21 days.In the other three groups,expression changes of cardiac collagen subtype Ⅰ,Ⅲ,fibronectin(FN),c-fos,ERK 1 (extracellular signal-regulated kinase,ERK)and PKC proteins were studied with immunohistochemistry and computer image analysis. c-fos mRNA expression was tested by reverse transcription and polymerase chain reaction(RT-PCR).Results Expressions of collagen Ⅰ,collagen Ⅲ , FN,c-fos,ERK 1 and PKC proteins were significantly enhanced(P

Objective Mapping the sites of earliest activation in AF patients with rheumatic heart disease. Finding out the ratio of AF originate from the pulmonary veins. Methods There were 9 patients with valvular atrial fibrillation (1 male, 8 females age (42?13) years, histories of rheumatic heart disease (11?9) years, and mitral valve area 1.01?0.02 cm2) involved in the research. 3 patients had organized thrombus in left atrial appendage. 6 patients with persistent AF received anticoagulation therapy (warfarin 2 or 3 weeks) and drug cardioversion (amiodarone 400 mg, three times per day, for 7 days) before procedures, while other 3 patients with paroxysmal AF received neither anticoagulation therapy nor drug cardioversion. All patients received percutaneous balloon mitral valvotomy (PBMV). After finished PBMV, four multipolar electrode catheters were placed in the high right atrium (HRA), coronary sinus (CS), left atrium (LA) and pulmonary veins (PVs). S1S2 and S1S2S3 programmed stimuli were delivered in HRA, CS, LA and PVs respectively. For the patients who failed to induce AF, burst stimuli were used. Results 11 AF generating sites, which induced by S1S2 and S1S2S3 programmed stimuli, could be confirmed by identification of the earliest regions of atrial activation for the first AF cycle. However, 1 AF obtained by 260 ms RR interval burst stimuli, affirmed by shortest activation cycle length. All confirmed 12 AF original sites were original as following: RA (n=4), LA (n=1), CS (n=2); PVs (n=5). Among the 5 PVs original sites, 3 was from left superior pulmonary vein, while the other 2 were from right superior pulmonary vein and left inferior pulmonary respectively. Conclusion PVs could be the ectopic origin of valvular AF.

Objective To study the incidence of and identity risk factors for hemorrhage and thromboembolism during long-term warfarin therapy.Methods All patients were studied in the People's Hospital of Peking University Anticoagulant Clinic from 2001-04 to 2003-11,in whom a course of warfarin therapy intended to last for more than 4 weeks.All bleeding and thromboembolism events were classified as minor or serious or fatal and life-threatening.Incidences of adverse events were analyzed statistically.Results A total of 128 patients were enrolled in the investigation,the median age of the study group was 67 years(ranged 25 to 83).There were 41 bleeding events occurring in 34 patients,and 5 events of thromboembolism.Age and hepatocirrhosis were significantly associated with bleeding complications(P=0.040 and P=0.014).Conclusion Hemorrhage is the major side effect of warfarin;age and hepatocirrhosis are significantly associated with bleeding complications.

Objective To determine whether the ?_2-adrenoceptor genetic single nucleotide polymorphisms are associated with atrial fibrillation.Methods A case-control study was performed on 218 subjects,including 58 subjects with lone atrial fibrillation,50 subjects with atrial fibrillation and essential hypertension,50 subjects with essential hypertension and 60 healthy controls.The ?_2-adrenoceptor polymorphisms at amino acids 16 and 27 were identified by allele specific polymerase chain reaction(PCR).Results The Gly/Gly genotype as well as the Gly16 allele at amino acids 16 was significantly more common in the atrial fibrillation group than in the non-atrial fibrillation group.But there was no significant differenece in the allele frequency or the genotype frequency of the Gln27 Glu polymorphism between the two groups.In addition,the difference in the distribution of polymorphisms at amino acids 16 and 27 between the four different observed groups was not significant either.Conclusion Gly16 polymorphism of the ?_2-adrenoceptor overrepresenting in the atrial fibrillation group seems to be associated with atrial fibrillation.

Objective To evaluate the frequently used electrocardiographic criteria and propose a modified algorithm for differentiating typical atrioventricular node reentrant tachycardia(AVNRT)from atrioventricular reciprocating tachycardia(AVRT).Methods Twelve-lead electrocardiograms(ECGs)during sinus rhythm and atrioventricular node reentrant tachycardia(AVNRT)or atrioventricular reciprocating tachycardia(AVRT)with a narrow QRS complex were obtained from 154 patients who had received successful radiofrequency catheter ablation from Jan.2003 to Nov.2005.The ECGs of initial 104 patients were analyzed by 3 observers without knowledge of the electrophysiological diagnosis.According to these initial results,we proposed a modified stepwise ECG algorithm which used pseudo r′/S/Q waves,RP interval,and ST-segment elevation in lead aVR during tachycardia.Two observers assessed the algorithm in additional 50 patients.Results The algorithm was able to increase the overall accuracy from 77% and 79% with original algorithm to 84% and 87% with the modified algorithm,respectively.The inter-observer concordance was 85%.The intra-observer concordance was 89% in both investigators.Conclusion The modified algorithm can improve the accuracy of differential diagnosis between typical AVNRT and AVRT via concealed accessory pathway.

Objective To investigate vagal effects on atrial fibrillation(AF)thresholds at different sites of pulmonary veins after autonomic denervation.Methods In 10 mongrel dogs,the cervical vagal trunks were isolated bilaterally and decentralized from Oct 2004 to May 2005.The ansae subclaviae were exposed bilaterally as they exited from the stellate ganglia,doubly ligated,and cut.Local rapid electrical stimulation(S1S1=80 ms,impulse duration 0.5 ms)was performed to right appendage(RAA)、left appendage(LAA)、left atrium(LA)and different sites of 4 pulmonary veins.AF threshold was determined at each site in the baseline state,during bilateral cervical vagal stimulation(VNS,12.5 Hz,impulse duration 0.5 ms,stimulation voltage 5～8 V)and during infusion of atropine.Results During VNS,a lower AF threshold was observed at all sites,especially at distal of 4 pulmonary veins(P0.05).Conclusion Vagal nerve not only contributes to the maintenance of AF originating from pulmonary veins,but also greatly promotes the initiation of AF.