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41.
The presented case reports on successful treatment with everolimus in a neonate with left ventricular giant rhabdomyoma. The authors used a different dosage regime compared to literature and documented rapid tumor regression by 3D echocardiography.  相似文献   
42.
43.
目的 总结外科手术治疗小婴儿期室间隔缺损(VSD)的临床经验.方法 对2000-2005年83例<6月龄VSD患儿,年龄12 d至6(4.3±1.2)个月,体重3~6.5(5.1±0.8)kg.膜周部VSD 74例,干下型VSD 8例,膜周部并肌部VSD1例.术前中、重度肺动脉高压69例(83.1%).所有患儿均在浅低温体外循环下手术.结果 全组手术死亡4例,手术病死率为4.8%.术后主要并发症为肺动脉高压危象、肺部感染和心律失常.结论 随着麻醉、体外循环、手术技术和围术期监护处理措施的进步,在小婴儿期施行VSD的外科手术已成为安全的治疗方式.术后对肺高压的处理是手术成功的关键.  相似文献   
44.
目的 :应用多普勒组织成像 (DTI)技术检测二尖瓣环舒张期运动速度来评介原发性高血压左室舒张功能 ,探讨DTI的临床应用价值。方法 :2 0例原发性高血压和 2 0例年龄相似的健康者 ,应用DTI技术对二尖瓣环室间隔侧的运动速度进行测定 ,并与常规二尖瓣血流脉冲多普勒 (PW)检测结果对照分析。结果 :PW高血压组与对照组比较 ,峰值速度E、A及E/A明显低于对照组 ,差异显著 (P <0 0 1) ;DTI高血压组与对照组比较 ,峰值速度Ea、Aa及Ea/Aa明显低于对照组 ,差异非常显著 (P <0 0 0 1)。PW、DTI两组相同部位间比较 ,高血压组低于对照组。结论 :DTI技术评价高血压左室舒张功能比常规脉冲多普勒二尖瓣血流参数更敏感  相似文献   
45.
AClinicalStudyofReversingLeftVentricularHypertrophyinHypertensivePatientsbyAdalatZhangFumin(张馥敏)XuDi(许迪)YongYonghong(雍永宏)Chen...  相似文献   
46.
Summary The effects of sodium salts of various bile acids on the contractile force and the electrophysiological properties of rat ventricular muscle were studied in vitro. Primary, conjugated, and secondary bile acids were studied in a concentration range of 10–9–10–6 mol/l, which corresponds to concentrations found in the plasm of patients with cholestatic jaundice. In general, the bile acid induced a negative inotropic effect which was manifested as a reduction in active tension, maximum rate of tension activation, and maximum rate of tension relaxation. Twitch duration and time to peak tension were unaffected by the bile acids. The negative inotropism was associated with a reduction in ventricular action potential duration. Resting potential, action potential amplitude, and maximum upstroke velocity of phase 0 depolarization were unaffected. Voltage clamp experiments in rat ventricular myocytes demonstrated that sodium taurocholate decreased the slow inward current and slightly increased the outward potassium current. Hence, these effects on the membrane currents are probably responsible for the negative inotropic effect. Send offprint requests to O. Binah at the above address  相似文献   
47.
目的 :观察静脉应用前列腺素E1(PGE1)、吸入一氧化氮 (NO)及二者小剂量联合应用对室间隔缺损 (VSD)并肺动脉高压的治疗作用。方法 :将 2 4例VSD并肺动脉高压的病人随机分为 3组 ,观察静脉注射PGE16 0ng/ (kg·min)、吸入NO 2 0ppm及静脉注射PGE130ng/ (kg·min)联合吸入NO 10 ppm对病人的血流动力学及血氧饱合度的影响。结果 :静脉注射PGE16 0ng/ (kg·min)使肺动脉平均压 (MPAP)明显下降 ,体动脉平均压 (MSAP)亦有所下降 ,心指数 (CI)明显增加。吸入NO 2 0 ppm组MPAP明显下降而MSAP无明显变化 ,CI有所升高 ,但差别不显著。静脉注射PGE130ng/ (kg·min)同时吸入NO 10 ppm组MPAP明显下降 ,但不显著 ,CI明显升高。 3组血氧饱合度均明显升高。结论 :联合应用小剂量PGE1和NO不仅能有效降低MPAP ,又能适当轻度降低MSAP ,改善心功能 ,减轻了NO的毒副作用 ,是一种较理想的治疗方案  相似文献   
48.
Characteristics of Bifocal Pacing:   总被引:1,自引:0,他引:1  
Bifocal RIGHT ventricular stimulation (BRIGHT) is an ongoing, randomized, single-blind, crossover study of atrial synchronized bi-right ventricular (RV) pacing in patients in New York Heart Association heart failure functional class III, a left ventricular ejection fraction <35%, left bundle branch block and QRS complexes ≥120 ms. This analysis compared the electrical and handling characteristics, and the complications of pacing at the RV apex (Ap) with passive, versus RV outflow tract (OT) with active fixation leads. A mean of 1.6 ± 0.9 and 2.2 ± 2.0 attempts were needed to position the Ap and OT leads, respectively (ns). R-wave amplitudes at Ap versus OT were 23 ± 13 mV versus 14 ± 8 mV (n = 36, P < 0.001). R-wave amplitudes at the Ap remained stable between implant and M7. R-wave amplitudes at the OT could not be measured after implantation. In two patients, atrioventricular block occurred during active fixation at the OT. Conduction recovered spontaneously within 4 months. Ventricular fibrillation was induced in one patient during manipulation of an Ap lead in the RV. Marked differences were found between leads positioned in the OT versus Ap, partly related to the difference in lead design. Mean R-wave amplitude was higher at the Ap that at the OT. Ease and success rate of lead implant was similar in both positions.  相似文献   
49.
Atrial fibrillation (AF) may be associated with activation of atrial natriuretic peptide (ANP). The exact trigger for the release of ANP is still being debated. Atrial volume, pressure, and wall stretch are considered to be the main determinants of ANP activation. The aim of the study was to evaluate plasma ANP concentrations in patients with persistent AF and to analyze the echocardiographic determinants of ANP concentration in this group. The study population included 67 patients, 59 ± 7 years of age, with a median AF duration of 5.5 months (range 0.1–12). The relationship between plasma ANP concentrations and echocardiographic left atrial (LA) diameter and volume, and left ventricular (LV) diameter and ejection fraction (EF) was analyzed by logistic regression analysis. The median baseline plasma ANP concentration was 63 pg/mL (range 21–126) in the study group versus 34 pg/mL (range 16–73) in a control group. The mean left antero-posterior atrial dimension, LA volume, LV enddiastolic diameter, and LVEF were 48 mm, 104 mL, 52 mm, and 54%, respectively. A significant linear positive correlation was found between plasma ANP concentration and maximal LA volume (r = 0.62, P < 0.01). A negative correlation was found between LVEF and plasma ANP concentration (r =−0.42, P = 0.01). However, by multivariate regression analysis, no echocardiographic parameter was an independent predictor of plasma ANP concentration. Plasma ANP concentrations were independent of echocardiographic measurements of LA size or LV size and function in patients with persistent AF.  相似文献   
50.
A case is presented of a patient with incessant venfricular tacbycardia of left bundle branch block morphology. Endocardial mapping revealed the site of earliest activation during tachycardia to be the proximal right ventricular septum. Pacing at this site elicited the clinical tachycardia, whereas pacing at the proximal left ventricular septum induced a right bundle branch block morphology identical to that of a previously recorded spontaneous ventricuiar tachycardia. Electrophysiological evidence is given that both types of tachycardia originate from a single reentry circuit located in the proximal ventricular septum in which the reentrant wavefront may travel either orthodromically (during spontaneous tachycardia and right ventricular pacing) or antidromically (during left ventricular pacing).  相似文献   
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