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In clinical practice,cardiac resynchronization therapy(CRT)delivered by biventricular pacing(BiVP)has been recommended to be applied in patients with heart failure and wide QRS to achieve biventricular electromechanical synchrony.Multiple previous clinical studies have demonstrated that BiVP can effectively improve cardiac function,reverse left ventricular remodeling,and reduce risk of all-cause mortality and heart failure rehospitalization.However,BiVP still faces technical challenges,such as coronary sinus intubation failure,no ideal target vein,phrenic nerve stimulation,unacceptable pacing threshold of left ventricular electrode,and risk of lead dislodgement.In addition,prior studies have found that about 30%-40%of patients with BiVP have no significant improvement in cardiac function,namely,CRT non-response.Conduction system pacing(CSP)includes His bundle pacing(HBP)and left bundle branch area pacing(LBBAP).HBP is the most physiological pacing technique at present.Due to the anatomical location and the limitations of pacing electrodes and delivery tools,the clinical application of HBP is difficult to be popularized.LBBAP is a novel physiological pacing modality and can overcome the limitations of HBP and achieve similar physiological effects to HBP.LBBAP can be further divided into left bundle branch pacing(LBBP)and left ventricular septal pacing(LVSP),based on the presence of left bundle branch capture.These two pacing modalities can correct left bundle branch block(LBBB)and narrow QRS duration.LBBAP has stable pacing parameters and low risk of significantly increased thresholds or loss of capture,showing great potential of clinical application.However,large-scale randomized controlled studies are necessitated to provide more robust evidence to demonstrate the feasibility and efficacy of LBBAP applied in patients with heart failure.BiVP,HBP and LBBAP have their own advantages and disadvantages in clinical practice,which are complementary to each other.Pacing strategies should be individually selected for heart failure patients with varied clinical characteristics to improve the response rate and clinical prognosis of heart failure patients receiving CRT.
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Objective: To investigate the relationship between high sensitivity C-reactive protein (hs-CRP) level and incidence of left atrial spontaneous echocardiographic contrast (LASEC) in the patients with nonvalvular atrial fibrillation (AF). Methods: Four hundred and ninety consecutive patients with nonvalvular atrial fibrillation who underwent radiofrequency ablation for the first time from January 1, 2018 to June 30, 2018 in the Department of Cardiology, Beijing Anzhen Hospital were enrolled. According to the results of transesophageal echocardiography before radiofrequency ablation, patients were divided into the group without LASEC (n=338) and the group with LASEC (n=152). hs-CRP was determined by latex enhanced immunoturbidimetry. The relationship between hs-CRP and LASEC in patients with nonvalvular atrial fibrillation was investigated by univariate and multivariate logistic analysis. Results: LASEC was detected in 152 (31%) of 490 patients. Significant differences in age, type of atrial fibrillation, previous embolic events, fibrinogen, D-dimer, the left atrial anteroposterior diameter and CHA(2)DS(2)-VASc scores were found between patients with and without LASEC (all P<0.05). Compared with the group without LASEC, the serum hs-CRP level was significantly higher in the group with LASEC (3.16 (1.30, 5.23) mg/L vs. 0.67 (0.37, 1.48) mg/L, P<0.001). Multivariate logistic regression analysis showed that hs-CRP (OR=1.136, 95%CI 1.060 - 1.217, P<0.001) and D-dimer (OR=1.040, 95%CI 1.011 - 1.070, P=0.007) were independent determinants for LASEC in this patient cohort. Conclusions: hs-CRP is an independent determinant for LASEC in patients with nonvalvular atrial fibrillation. Inflammation may thus be involved in the formation of prethrombotic state in patients with nonvalvular atrial fibrillation.
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Humanos , Apêndice Atrial , Fibrilação Atrial/epidemiologia , Proteína C-Reativa , Ecocardiografia Transesofagiana , Eletrocardiografia , Átrios do Coração , Incidência , Fatores de RiscoRESUMO
Objective: To investigate the impact of history of hypertension and blood pressure levels on the thromboembolism risk in the setting of nonvalvular atrial fibrillation (NVAF). Methods: China Atrial Fibrillation Registry Study prospectively enrolled 25 512 atrial fibrillation (AF) patients between August 2011 and December 2018. After exclusion of patients with valvular AF, hypertrophic cardiomyopathy, receiving anticoagulation or ablation therapy at the enrollment, 7 757 patients were included in analysis. The primary endpoint was the time to the first occurrence of ischemic stroke or systemic embolism. Cox proportional hazards models were performed to evaluate whether a history of hypertension or blood pressure levels were independently associated with thromboembolism. Results: During a mean follow up of (35±25) months, 455 (5.9%)thromboembolic events occurred. The crude incidence rate of thromboembolism in patients with a history of hypertension was higher than that in patients without hypertension (2.38 vs. 1.35 per 100 patient-years, χ²=16.8,Log-rank P<0.001). Patients were further divided into 4 groups according to systolic blood pressure (SBP) levels at baseline, the crude incidence rate of thromboembolism significantly increased in proportion to the elevation of SBP levels (χ²=17.9,Log-rank P<0.001). However, there was no significant difference in thromboembolism risk among 4 groups stratified by diastolic blood pressure (DBP) levels (χ²=0.6,Log-rank P=0.907). Multivariable regression analysis showed that history of hypertension was independently associated with a 27% higher risk of thromboembolism (HR=1.27, 95%CI 1.01-1.61, P=0.045). Patients with SBP≥140 mmHg (1 mmHg=0.133 kPa) was associated with 36% higher risk of thromboembolism than patients with SBP<120 mmHg (HR=1.36, 95%CI 1.02-1.82, P=0.036). However, patients with SBP 120-129 mmHg or 130-139 mmHg were not at a higher risk of thromboembolism as compared to the patients with SBP<120 mmHg (SBP 120-129 mmHg: HR=1.23, 95%CI 0.90-1.67, P=0.193; SBP 130-139 mmHg: HR=1.30, 95%CI 0.95-1.77, P=0.098). In addition, DBP levels were not independently associated with the increased thromboembolism risk. Conclusion: A history of hypertension and SBP≥140 mmHg are independent predictors of thromboembolism risk in patients with NVAF. These results indicate that intensive efforts to lower SBP below 140 mmHg might be an important strategy to reduce the risk of stroke in patients with NVAF.
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Humanos , Fibrilação Atrial , Pressão Sanguínea , China , Hipertensão , Fatores de Risco , Acidente Vascular Cerebral , TromboemboliaRESUMO
<p><b>AIM</b>To study the effect of lomerizine (Lom) on the reversal of multidrug resistance (MDR) in K562/ADM cells and its mechanism.</p><p><b>METHODS</b>MTT assay was used to determine the influence of Lom on the cytotoxicity of adriamycin (ADM). The effect of Lom on the apoptosis induced by ADM and vincristine (VCR) in K562/ADM cells was detected using flow cytometry. Intracellular accumulation of ADM was measured by fluorescence spectrophotometry. Flow cytometry was used to investigate the efflux of rhodamine 123 (Rh123) and the expression of P-glycoprotein (P-gp) in K562/ADM cells.</p><p><b>RESULTS</b>Lom increased the cytotoxicity of ADM and the apoptosis induced by ADM or VCR in K562/ADM cells. At the concentration of 3, 10 and 30 micromol x L(-1), Lom reduced the IC50 value of ADM from 79.03 micromol x L(-1) to 28.14, 8.16 and 3.16 micromol x L(-1), respectively. Lom increased the intracellular accumulation of ADM and inhibited the efflux of Rh123 in K562/ ADM cells. No change in P-gp expression was observed after the treatment of Lom for 72 h.</p><p><b>CONCLUSION</b>Lom had strong reversal effect on MDR in K562/ADM cells by inhibiting P-gp function.</p>