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Cardiac arrhythmias are varied and very common. They are usually classified as bradyarrhythmias and tachyarrhythmias, which are treated according to their own common principle separately. There is no long term effective oral drugs that can be used to treat bradyarrhythmias effectively up to now. Pacemaker is still the only effective treatment for it. Now catheter ablation has already applied to almost every kind of tachyarrhythmias, and which is the first choice for treating supraventricular tachycardia and atrial flutter because of the satisfactory result. Most patients with other types of tachyarrhythmias, especially atrial fibrillation and all kinds of premature beats are still given drug therapy. Amiodarone, propafenone, sotalol and mexiletine are common used antiarrhythmic drugs in our country. This article overviewed the principle and the matters need to attention in the drug therapy of cardiac arrhythmias.
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Objective: To observe the automatic ventricular capture management (VCM) conifrmed by paced depolarization integral (PDI) evoked response detection via the follow-up study in patients with Zephyr5826 pacemaker implantation. Methods: A total of 102 relevant patients were enrolled. In order to conduct PDI calculation, pacemakers were set by bipolar sensing and bipolar pacing at immediately after implantation. VCM functions were observed at 1 day, 7 days and 1 month, 3, 6, 12 months after implantation, the ventricular threshold by VCM test and manual test were compared. The symptoms of pectoralis major stimulus, diaphragm stimulus and palpitation were observed in all follow-up patients. Results: There was 1 patient died by MI at 1 month after Zephyr5826 pacemaker implantation, the rest 101 patients were followed-up for 12 months. VCM function was successfully turned-on at immediately after implantation in all patients, no pectoralis major stimulus and diaphragm stimulus occurred. VCM function was turned-off in 6/101 (5.9%) patients at 7 days after implantation due to intolerable palpitation caused by daily automatic VCM, instead they received manual test at follow-up visit. The coincidence rate of ventricular thresholds between VCM test and manual test were 100%. Ventricular pacing output voltage by VCM was (0.99 ± 0.48) V,n=608. Compared with regular pacing output voltage (2.5V, 0.4ms), VCM function may save 84% of energy consumption; compared to high pacing output voltage (3.5V, 0.4ms), VCM may save 92%. Loss of ventricular capture and poor sensation were not found by ECG and 24 h dynamic monitoring. Conclusion: Zephyr5826 pacemaker may conduct bipolar pacing and scanning with VCM function, it can be effectively and safely operated by low energy output. A few patients may not use VCM function due to intolerable palpitation.
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Objective To evaluate the effects of the administration of intracoronary diltiazem before the occurrence of no-reflow during direct PCI. Mtthods One hundred and thirty four AMI patients hospitalized from June 2001 to November 2003 were selected as research objects. 60 patients with AMI received intracoronary diltiazem before the occurrence of no-reflow during direct PCI. 74 AMI patients did not receive intracoronary diltiazem and were enrolled as control subjects. Patients with refractory low blood pressure and complete atrioventricular block before PCI were excluded. Thrombolysis in Myocardial Infarction (TIMI) flow grade, corrected TIMI frame count (CTFC) were assessed during angiography, before and after PCI. Results The two groups had similar baseline. There were significant difference in post-PCI no reflow assessment (P = 0.04) and CTFC (P = 0.00). Conclusion Early administration of intracoronary diltiazem during direct PCI reduces the no reflow occurrence.
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Objective To investigate the clinical value of the gated blood pool imaging phase analysis method in the evaluation of left ventricular mechanical synchronization in patients with chronic heart failure. Methods A total of 169 patients with chronic heart failure were enrolled in our study , using gated blood pool imaging phase analysis method to obtain left ventricular phase angle width ( PHB) and left ventricular phase angle standard deviation ( PSD) as evaluating left ventricular mechanical synchrony index; using tissue Doppler imaging (TDI) measurement of the standard deviation of systolic peak time(Ts-SD) of each segment by using the current prevailing 12 non-apical segments analysis method as evaluating left ventricular mechanical synchrony index, and parameters derived from both methods were compared. Results LVPHB was highly correlated with Ts-SD (r = 0. 83 ,P = 0. 000 ) . LVPSD was modestly correlated with Ts-SD ( r - 0. 69, P = 0. 000) . The ejection fraction measured by echocardiography was (42.93 ± 14. 89) % ,which was significantly higher than that measured by ERNA (39. 76 ± 17. 89)% (P <0. 01). Conclusions The evaluation of left ventricular mechanical synchrony in patients with chronic heart failure by the gated blood pool imaging can provide similar information with TDI, which can simultaneously measure two ventricular functions and get more accurate measurement of ejection fraction. Cardiac resynchronization therapy patients can be identified by combining two kinds of approaches, and cardiac resynchronization therapy responders could be improved as well. More patients with heart failure can benefit from cardiac resynchronization therapy therapy.
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Objective To investigate the relationship between coronary myocardial bridge and the symptoms of the patients and its related factors, and to provide evidence for rational treatment. Methods Sixty-one patients di-agnosed as myocardial bridge by coronary angiography and the examination of nuclide myocardial perfusion imaging were recruited and their clinical data was analyzed retrospectively. The patients were divided into ischemic group and non-ischemic group according to the nuclide imaging, and were followed up on the compliance of β-blocker taking and the symptoms. Results Among the 61 patients ,7 patients were ischemic,and the others were non-ischemic. There was no significant difference on symptoms between the two groups (P>0.05). The prevalence of Grade Ⅲ narrowing was higher in ischemic group (6/7) than that in the non-ischemic group (18/54) (χ~2=5. 009, P = 0.024) ,and the ischemic patients with Grade Ⅲ narrowing were older than those in the non-ischemic patients. Two patients in the ischemic group did not insist on taking β-blocker and their symptoms did not change,40 patients in the non-ischemia group did not insist on taking β-blocker,of which 33 patient's symptoms were improved. The symp-toms of all patients with good compliance of β-blocker taking were improved. Conclusions The symptoms of some patients are unrelated with myocardial bridge and treatment is not recommended.
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Objective: To observe the influence of different tocopherol isoforms on oxidized low density lipoprotein (oxLDL) or recombinant human C reactive protein (rhCRP) induced expression of intercellular adhesion molecule 1 (ICAM 1) in human umbilical vein endothelial cells (HUVECs) and to investigate the potential mechanisms and effects of different tocopherols on atherosclerosis. Methods: Cultured HUVECs were incubated with oxLDL,oxLDL+? tocopherol,oxLDL+? tocopherol,oxLDL+mixed tocopherols,rhCRP,rhCRP+? tocopherol,rhCRP+? tocopherol, rhCRP+mixed tocopherols for 24 hours, respectively. The ICAM 1 expressions of protein and mRNA were detected by cell enzyme linked immunosorbent assay (ELISA), flow cytometric technique and RT-PCR. Results : Incubation of HUVECs with oxLDL or rhCRP for 24 hours significantly increased ICAM 1 expressions of proteins and mRNA . The different tocopherols inhibited oxLDL induced ICAM 1 expression in HUVECs in a concentration dependent manner(50-200 ?mol/L) and mixed tocopherols were more potent than ? tocopherol or ? tocopherol alone. However, rhCRP induced ICAM 1 expression in HUVECs was not inhibited by tocopherols. Conclusion :The different tocopherols inhibited oxLDL induced ICAM 1 expression in HUVECs and mixed tocopherols were more potent than ? tocopherol or ? tocopherol alone, which may be important for the beneficial effects of tocopherols on atherosclerosis and cardiovascular disease.
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] AIM: To investigate the expression of the urotensin Ⅱ (UⅡ) receptor GPR14 in the aorta of apoE knockout mouse. METHODS: The expression of GPR14 in the aorta of apoE knockout C57BL/6J mice at various ages (18 weeks, 28 weeks, and 38 weeks old, respectively) was determined with competitive RT-PCR. A binding assay of [ 125 I]-UⅡ on the aortic tissue was also performed in 28 weeks group. RESULTS: We found significant upregulation of GPR14 mRNA at all three ages. Compared with wild type group at the same age, the GPR14 mRNA level in apoE knockout mice increased 54.2% in 18 week group (P
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Objective To estimate whether a change in the polarity of low atrial electrograms recorded near the ablation line is an accurate indicator of complete isthmus block in the radiofrequency ablation of typical atrial flutter. Methods Radiofrequency ablation was performed in 10 patients with typical atrial flutter. Electrograms were recorded around the tricuspid annulus using a duodecapolar halo catheter and the distal electrode of halo catheter positioned just near the ablation line. The electrogram polarity of the distal electrode pair (H potential) was analyzed during atrial flutter and during coronary sinus pacing before and after ablation. Results Radiofrequency ablation was performed during coronary sinus pacing in 8 patients and performed during atrial flutter in 2 patients. Complete isthmus block was achieved in all patients. Before ablation, the initial polarity of H potential was predominantly positive during coronary sinus pacing and predominantly negative during atrial flutter. After complete isthmus block was achieved, the initial polarity of H potential was predominantly negative during coronary sinus pacing in all the patients. Conclusion The change of the electrogram polarity recorded just near the ablation line during coronary sinus pacing after ablation of typical atrial flutter is a simple, quick and accurate indicator of complete isthmus block.
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The safety and effectiveness of catheter ablation in coronary sinus using radiofre-quency energy was studied in 16 dogs. Radiofrequency energy(1229?711 J) was applied between electrode catheter placed inside coronary sinus and a chest wall patch. Thirteen dogs were killed approximately half an hour after ablation and three 3 to 4 weeks. Lesion of abltion area were 3. 2?1. 8mm in length, 2. 2?1. 7mm in width and 2. 1?1. 0mm in depth. Microscopic examination showed well circumscribed area of coagultion necrosis (acute period)and fibrosis (chronic period). The coronary atery and mitral apparatus were not involved,nor was the endocadium. No arrhyth-mias except occationally atrial or ventricular premature beats were observed. No hemodynamic changes and rupture of coronary sinus occurred in any dog. Large amount of radiofrequency energy can be safely applied to the coronary sinus. The location of the lesions produced suggests that this technique may be useful for interruption of left-sided atioventricular pathways of patients.