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AIM:Chronic heart failure (CHF), caused by ischemic cardiomyopathy (ICM) and nonischemic cardiomyopathy (NICM), is among the leading causes of mortality and morbidity worldwide .Low-density lipoprotein receptor-related protein 6 (LRP6) plays a criti-cal role in regulating Wnt signaling .Dysregulated Wnt signaling contributes to high incidence of arrhythmias .Thus, there might be an association between genetic variations of LRP6 and sudden cardiac death ( SCD) .The objective of the study was to examine the associ-ation between common variants of LRP6 and prognosis of CHF patients .METHODS:From July 2005 to December 2009, patients with CHF referred from 10 hospitals and participants without structural heart disease in China were undergone a prospective study .The sin-gle-nucleotide polymorphism rs 2302684 was selected to evaluate the effect of LRP6 polymorphisms on the survival of the patients .RE-SULTS:A total of 1 887 patients (1 437 with CHF and 450 in the control group)were finally enrolled for the analysis.During a medi-an follow-up of 61 months, a total of 546 (38.00%) patients died, including 201(36.81%) cases with SCD and 345 (63.19%) ca-ses with NSCD.No end point event occurred in the control group .Patients carrying A allele of rs2302684 had increased risks of all-cause death (PA in LRP6 is associated with an increased risk of all-cause death and SCD in patients with CHF in Chinese Han population , and the association is more prevalent in patients with CHF caused by ICM.Thus, LRP6 might be added as a novel predictor of SCD and could provide an attractive and direct therapeutic target in SCD prevention .
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Objective To describe the clinical characteristics of idiopathic ventricular fibrillation (IVF) with fragmented QRS complex (f-QRS) and J wave in resting electrocardiogram. Methods We reviewed data from 21 case subjects in our hospital who were resuscitated after cardiac arrest due to IVF and assessed the prevalence of f-QRS and J wave in resting electrocardiogram (ECG). All the case subjects were classified among three groups based on the electrocardiographic morphology: group I, both f-QRS and J wave were observed (n = 6), group II, only J wave was observed (n = 9), group III, neither f-QRS nor J wave was observed (n = 6). Population characteristics, history of syncope or sudden cardiac arrest, incidence of ventricular fibrillation (VF), and circumstance of VF were evaluated among the three groups. Results The incidence of index events (syncope, survived cardiac arrest and VF episodes recorded in implantable cardioverter defibrillator (ICD) or pacemakers) was 13.4 ± 5.6 per-year in group I, 10.8 ± 3.9 per-year in group II, and 9.8 ± 4.2 per-year in group III. There were significant differences in incidences among the three groups, the most frequent index events were observed in group I. The hazard ratio for incidence was 3.2 (95%CI, 1.1-7.9; P = 0.01). The history and circumstance of the index events were different among the groups. In group I, all the index events occurred during sleep in early morning. In group II, four subjects suffered VF during strenuous physical activities or agitation state, two during sleep in early morning, three in usual activity. In group III, one subject suffered VF during sleep in early morning, one in agitation state, four in usual activity. Conclusions This study suggests that the IVF patients with the combined appearance of f-QRS and J wave in the resting ECG suffer an increased risk of VF, this subgroup of IVF patients has a unique clinical feature.
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Objective To study the factors influencing the outcome of patients suffering from in-hospital ventricular fibriUation (IHVF), as there have been few studies focusing on this topic. Methods Patients with IHVF collected in a single cardiac center were classified into a successful group and a failure group. Data relevant to the predicting factors of the two groups were compared. Results There were 206 events in the analysis. The most common underlining disease was coronary artery disease (CAD), especially acute myocardial infarction (AMI). On multiple logistic regression analysis, it was shown that the independent predictors for failure of defebriUation were higher NYHA class (OR 1.7, 95% CI 1.3-2. 2,P <0.001), higher blood potassium level (OR 2.9, 95% CI 1.9-4.3, P =0.007) and adrenaline usage (OR 25.0, 95% CI 11.5-55. 1, P <0.001). In a AMI sub-group, 56. 9% of the IHVF events occurred within the first day of AMI, and the occurrence descended with time going on within 2 weeks. Before the occurrence of IHVF, the patients with right coronary artery as the infarction related artery (IRA) often suffered from(8/9, 88.9%) bradycardia (R-R interval > 1 s), but those with left anterior descending artery as IRA often showed (8/12, 66.7%) tachycardia (RR interval < 0.6 s). Conclusions The common disease causing IHVF is CAD. The worse the heart function, the higher the rate of IHVF and the worse theprognosis. It IHVF not induced by hypokalemia and use of adrenaline in resuscitation predict lower successful defibrillation rate.
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<p><b>OBJECTIVE</b>To analyze the unipolar electrogram from successful and unsuccessful ablation sites of focal atrial tachycardia (AT), and to evaluate its value in the identification of successful targets.</p><p><b>METHODS</b>Fifteen consecutive patients with focal AT were referred for radiofrequency catheter ablation (RFCA). Both unipolar (from the tip electrode of ablating catheter) and bipolar (from the distal pair of electrode of ablating catheter) electrograms were used to identify the ablation targets of focal AT.</p><p><b>RESULTS</b>Successful ablation was echieved in 14 patients. Radiofrequency energy was delivered at a total of 27 sites. The bipolar electrograms associated with successful ablation sites showed earlier atrial deflection relative to P wave onset (36 ms +/- 15 ms vs 30 ms +/- 11 ms, P < 0.05) than the electrograms associated with failed ablation sites. At the 14 successful ablation sites, the unipolar electrograms displayed a completely negative atrial wave ("QS" morphology) beginning with intrinsic deflection. However, at the 13 unsuccessful ablation sites, a "rS" morphology of atrial wave was shown on the unipolar electrogram.</p><p><b>CONCLUSION</b>The "QS" morphology of the atrial wave on unipolar electrograms appears to represent a reliable marker for identifying the successful ablation targets of focal AT, with a high sensitivity and specificity.</p>