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71.
目的研究AT1受体拮抗剂缬沙坦对正常大鼠心室肌细胞L-钙电流(Ica-L)的影响。方法采用全细胞膜片钳技术,观察0.4μmol/L的缬沙坦引起单个大鼠心室肌细胞L型钙通道电流变化。结果0.4μmol/L缬沙坦使正常大鼠心室肌细胞L型钙电流峰值明显降低(P<0.01),I-V曲线上移,但不改变其激活电位、峰值电位和反转电位。不影响通道稳态激活曲线,使稳态失活曲线左移。结论0.4μmol/L缬沙坦可直接阻断大鼠心室肌细胞L型钙通道,改变心室肌细胞的电生理特性,可能是其抗心律失常的机制之一。  相似文献   
72.
目的探讨中性粒细胞与高密度脂蛋白胆固醇( HDL-C)的比值( NHR)对 AMI病人发生院内 MACE的预测价值以及 NHR与 Gensini评分量化的冠状动脉病变严重程度、左室射血分数( LVEF)量化的心脏泵功能的潜在关联。方法纳入 2018年 1月至 2022年 1月东南大学附属中大医院住院并接受冠状动脉造影的 546例 AMI病人。收集人口统计学数据、临床资料及计算 Gensini评分,依据住院期间是否发生 MACE,分为 MACE组( n=105)和非 MACE组( n=441)。使用受试者操作特征曲线(ROC曲线)检验 NHR预测院内 MACE的能力,并确定最佳截断值。使用多因素 logistic回归分析院内 MACE的影响因素,时,采用线性回归分析 NHR对 Gensini评分、 LVEF值的影响,并通过 Graphpad prism绘图进行可视化处理。院内 MACE定义同为:住院死亡、心源性休克、致血流动力学紊乱的恶性心律失常(包括室颤、持续性室速、高度及三度房室传导阻滞)等。结果MACE组的 NHR[13.64(9.89,18.19)]显著高于非 MACE组[7.73(5.83,10.07)]并且 NHR对 AMI病人院内 MACE具有较强的预测价值[AUC:0.84,95%CI:(0.79,0.88),P<0.001]调整混杂因素后,多因素二元,logistic回归分析显示 NHR是 AMI病人院内MACE的独立危险因素[OR:1.29,95%CI:(1.16,1.43),P<0.001]。线性回归分析显示 NHR与 AMI病人 Gensini评分呈显著正相关( P<0.001)与 LVEF呈显著负相关( P<0.001)。结论,本研究证实 NHR是 AMI病人院内 MACE的有力预测指标,是院内MACE的独立危险,因素之一,与 Gensini评分量化的冠状动脉病变严重程度呈显著正相关,与 LVEF量化的心脏泵功能呈显著负相关,可用于早期识别 AMI病人院内 MACE的高危人群,辅助临床诊疗。  相似文献   
73.
Accessory mitral valve tissue (AMVT) is a rare congenital cardiac anomaly, which is associated with other congenital heart diseases. It is diagnosed in neonates or childhood and rarely in adulthood. Nevertheless, AMVT is an incidental finding or described as isolated. Echocardiography, especially three-dimensional echocardiography is considered as an optimal imaging technique for AMVT diagnosis. We herein presented an asymptomatic adult AMVT cases with significant left ventricular outflow tract obstruction and surgical excision was recommended.  相似文献   
74.
心肌康对左心室肥厚逆转作用的临床研究   总被引:10,自引:0,他引:10  
本研究应用中药心肌康对左心室肥厚患者进行逆转性治疗。94例LVH患者随机分为心肌康治疗组和美多心对照组,作服药前4事的临床疗效观察。结果表明:心肌康对LVH有显著的退缩作用,对照组对LVH的治疗虽有一定程度的改善,但无统计学意义,两组于治疗比较亦呈显著性差异。  相似文献   
75.
Aims: The relationship between left ventricular (LV) function and AF detection in embolic stroke of undetermined source (ESUS) patients with insertable cardiac monitors (ICMs) remains unclear. We investigated the association between LV function and AF detection in patients with ESUS after ICMs implantation. Methods: We enrolled patients with ESUS who underwent ICMs implantation from September 2016 to September 2020 using a single-center, prospective registry. LV systolic and diastolic functions were assessed on precordial echocardiography by LV fractional shortening (LVFS) and average E/e’, respectively. Associations between characteristics of LV function and detection of AF by ICMs were analyzed. Results: Participants comprised 101 patients (median age, 74 years; male, 62%). During a median follow-up period of 442 days (interquartile range (IQR), 202–770 days), AF was detected in 24 patients (24%). Median duration from ICMs implantation to AF detection was 71 days (IQR, 13–150 days). When LVFS and E/e’ were dichotomized by cutoff value, each of low LVFS (<35.5%; adjusted hazard ratio (HR), 4.77; 95% confidence interval (CI), 1.77–12.9) and high E/e’ (≥ 8.65; adjusted HR, 4.56; 95%CI, 1.17–17.7) were independently associated with AF detection after adjusting for age and sex. When patients were divided into four groups according to dichotomized LVFS and E/e’, the combination of low LVFS and high E/e’ was independently associated with AF. Conclusions: In patients with ESUS after ICMs implantation, the LV characteristics of low LVFS and high E/e’ were associated with AF detection.  相似文献   
76.
Open in a separate window OBJECTIVESThe appropriate approach for surgical repair of coarctation of the aorta with a ventricular septal defect (VSD) remains controversial. This study evaluated the outcomes of primary repair of VSDs with periventricular device closure without cardiopulmonary bypass through a left thoracotomy in patients without arch hypoplasia.METHODSWe selected 21 patients aged <1 year, including 7 neonates, who underwent repair of coarctation of the aorta with periventricular device closure of a VSD.RESULTSThe median occluder size was 6 (range, 5–8) mm. The median mechanical ventilation time was 14 (range, 2–68) h, and the median duration of hospital stay was 11 (range, 7–16) days. No reoperations were required to correct VSD shunting, and the median residual shunt size was 1 (range, 1–2) mm. The median follow-up period was 13 (range, 4–31) months. No late deaths were reported, and no haemodynamically significant pressure gradient at the anastomotic site was observed. The median distal aortic arch z-score was 0.39 (range, −0.1–to 0.9). Only 1 patient had a permanent pacemaker implanted towards the end of the follow-up period.CONCLUSIONSPeriventricular device closure can be used safely for closure of VSD in children with coarctation of the aorta without a hypoplastic aortic arch, even in neonates, to reduce the risk of prolonged cardiopulmonary bypass. This hybrid approach can be performed with a low incidence of rhythm disturbances and residual shunting. However, a meticulous assessment of the VSD anatomy is essential to avoid any unfavourable events.  相似文献   
77.
Rationale:The treatment of dilated cardiomyopathy (DCM) has recently been greatly improved, especially with the widespread use of sacubitril/valsartan (ARNI) combination therapy. We know that ARNI-like drugs can significantly improve the symptoms of heart failure with reducing ejection fraction. However, clinical studies evaluating the safety and efficacy of ARNI in DCM-associated arrhythmia are limited, and whether individuals with arrhythmia would benefit from ARNI remains controversial. In this case, we report a patient with complete left bundle branch block (CLBBB) associated with DCM whose CLBBB returned to normal after treatment with ARNI.Patient concerns:A 38-year-old man was admitted to the hospital for 20 days for idiopathic paroxysmal dyspnea. He presented with exacerbated dyspnea symptoms at night, accompanied by cough and sputum.Diagnosis:Physical examination revealed a grade 4/6 systolic murmur could be heard in the apical area of the heart and mild edema was present in both lower limbs. Laboratory examination found that the B-type natriuretic peptide was significantly increased. Echocardiography indicated left atrial internal diameter, right ventricular internal diameter, and left ventricular diastolic diameter were enlarged and ejection fraction was significantly decreased. Besides, the pulsation of the wall was diffusely attenuated. Electrocardiogram was suggestive of tachycardia and CLBBB. A diagnosis of DCM with CLBBB was considered based on a comprehensive evaluation of the physical examination, laboratory examination, echocardiography and electrocardiogram.Interventions:The patient was treated with ARNI at a dose of 50 mg (twice a day) at first, gradually increasing to the target dose (200 mg, twice a day) in the following 9 months as shown in Table Table1,1, along with metoprolol 25 mg (once a day [qd]), diuretics 20 mg (qd), and aldosterone 20 mg (qd).Table 1Specific medications used in treatment.
Month(s) and dates after dischargeMorning (ARNI)Night (ARNI)Metoprolol 23.75 mg QD;
diuretics (furosemide) 20 mg QD;
aldosterone 20 mg QD
Month 1 (28/02/20–27/03/20)50 mg50 mg
Month 2 (27/03/20–26/04/20)100 mg50 mg
Month 3–4 (26/04/20–28/06/20)100 mg100 mg
Months 5–7 (28/05/20–29/08/20)150 mg100 mg
Months 8–11 (29/08/20–13/11/20)150 mg150 mg
Month 11–present (13/11/20–)200 mg200 mg
Open in a separate windowARNI = sacubitril/valsartan, QD = once a day.Outcomes:After treatment with ARNI during the 9-month follow-up, the patient’s symptoms improved, and CLBBB returned to normal.Lessons:Clinical studies evaluating the safety and efficacy of ARNI in DCM-associated arrhythmia are limited, and whether individuals with arrhythmia would benefit from ARNI remains controversial. This report will help to instruct the clinical treatment of DCM patients with CLBBB and the potential application of ARNI.  相似文献   
78.
Current evidence on the effects of continuous positive airway pressure (CPAP) on cardiac mechanics in patients with obstructive sleep apnea (OSA) is based on a few single studies. The authors investigated this topic through a meta‐analysis of speckle tracking echocardiography (STE) studies that provided data on left ventricular (LV) and right ventricular (RV) mechanics as assessed by global longitudinal strain (GLS). The PubMed, OVID‐MEDLINE, and Cochrane library databases were systematically analyzed to search English‐language review papers published from inception to January 31, 2022. Studies were identified by crossing the following terms: “obstructive sleep apnea”, “sleep quality”, “sleep disordered breathing”, “continuous positive airway pressure therapy”, “noninvasive ventilation”, “left ventricular hypertrophy”, “systolic dysfunction”, “global longitudinal strain”, “left ventricular mechanics”, “right ventricular mechanics”, “echocardiography” and “STE echocardiography”. The meta‐analysis, including a total of 337 patients with OSA from nine studies (follow‐up 2–24 months) showed a significant GLS improvement in both LV and RV after CPAP, standard mean difference (SMD) being 0.51±0.08, CI:0.36–0.66, p = .0001 and 0.28±0.07, CI:0.15–0.42, p = .0001), respectively. Corresponding SMD values for LV ejection fraction (LVEF) and tricuspid annular plane systolic excursion (TAPSE) were 0.20±0.06, CI:0.08–0.33, p = .001 and 0.08±0.06, CI: ‐0.04/0.20, p = .21. Our meta‐analysis suggests that: I) CPAP treatment exerts beneficial effects on biventricular function in patients with OSA; II) the assessment of cardiac mechanics by STE should be routinely recommended for monitoring cardiac function in this setting, due to limitations of conventional echocardiography in evaluating biventricular performance.  相似文献   
79.
目的 评价导管射频消融(radiofrequency catheter ablation,RFCA)对特发性室速(idiopathic ventricular tachy-cardia,IVT)的治疗效果以及心电图对消融靶点的定位价值.方法 对126例特发性室速患者的电生理资料及RFCA治疗效果进行回顾性分析.多数患者采用激动顺序标测,射频能量采用温控法(60~65℃).结果 126例患者中右室流出道(right ventricular outflow tract,RVOT)IVT 62例、左后间隔IVT 43例,其他部位IVT 21例.本组RFCA的总成功率为87.3%,RVOT-IVT和左后间隔IVT的成功率显著高于其他部位IVT(96.8%和90.7% vs 52.4%,P<0.05).本组8例患者存在发作性晕厥(发作的R-R间期230~260 ms),其中4例合并房室结双径路、2例合并隐匿性房室旁道、2例合并多形性室速.随访6个月至10年,复发9例(复发率为8.2%),均再次RFCA成功.合并心动过速性心肌病者6例,术后3个月心脏大小与心功能均恢复正常.结论 采用激动顺序标测法RFCA治疗IVT成功率高;室速发作时体表心电图对绝大多数室速起源具有定位价值;部分室速可能合并房室旁道或房室结双径路.  相似文献   
80.
心室流出道(ventricular outflow tract,VOT)起源室性早搏(premature ventricular contraction,PVC)因临床常见,具有典型的心电图(ECG)特征,诊断并不困难,射频消融术是该病非药物治疗的主要手段。文中报道1例初步诊断右心室流出道起源(RVOT)的PVC的患者,于左心室流出道(LVOT)获得成功消融的诊治经过。文献复习了PVC定位的方法、VOT局部独特的解剖特点对定位的影响,以及三维标测新技术对PVC消融手术的帮助。  相似文献   
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