Changes of Left Ventricular Geometry Shape and Left Ventricular Regional Function in Patients With Dilated Cardiomyopathy

To assess the left ventricle regional systolic and diastolic function, left ventricle geometry and left venticle sphericity indexes in patients with dilated cardiomyopathy （DCM） by quantitative tissue velocity imaging （QTVI）. Methods Thirty normal subjects and 52 DCM patients underwent QTVI and colour Doppler flow imaging study in order to measure the left ventricular regional function along left ventricle apical long-axis view and the left ventricle geometry. Peak tissue velocities of left venticle regional muscular tissue during systole （ Vs）, systolic acceleration （ a）, early diastole（Ve） and left atrium contraction（Va） along left venticle apical long axis view were measured. The indexes of left ventricular regional systolic and diastolic function were mearsured at the same time. The left ventricle geometry shape was reflected from the systolic and diastolic sphericity index （Sis and Sid）, the left ventricular ejection fraction （LVEF） and D wave / A wave （PVd/PVa） of pulmonary veins flowing spectrum reflected the global left ventricular systolic and diastolic function. The Vs, Ve, Va, a, PVd/PVa ratio, LVEF, Sis, Sid and their correlations between normal subjects and patients with DCM were compared and analyzed. Results Vs, Ve, Va, a, PVd/PVa, Sis and Sid in patients with DCM were lower than those in normal persons. There were significant relations between Sis and a （ r = 0. 6142, P 〈 0. 05）, Ve/Va and Sid （ r = 0. 6271, P 〈 0. 05 ）. Conclusions QTVI offer a newer method which has a higher sensitivity and accuracy in evaluating the left venticle regional systolic and diastolic function in DCM patients. There was significant relation between regional cardiac function and left venticle sphericity. （ S Chin J Cardiol 2009; 10（1） ： 9 -14）     

Epicardial Macro-Reentrant Ventricular Tachycardia Exhibiting an Endocardial Centrifugal Activation Pattern in a Case with Arrhythmogenic Right Ventricular Cardiomyopathy

A 55-year-old man with arrhythmogenic right ventricular cardiomyopathy underwent catheter ablation of ventricular tachycardia (VT) with left bundle branch block and left superior axis QRS morphology with an early precordial transition. Endocardial mapping during the VT revealed a focal activation pattern from a small region of low voltage in the left ventricular (LV) septum. Despite earliest endocardial activation in the LV septum, epicardial mapping demonstrated a macro-reentrant circuit with successful catheter ablation at an inferior peritricuspid annular site. Activation from the reentrant circuit propagated through the scar area in the epicardial right ventricle to the remote endocardial LV breakout site.     

ST Segment “Hump” during Exercise Testing and the Risk of Sudden Cardiac Death in Patients with Hypertrophic Cardiomyopathy

Background: The appearance of a discrete upward deflection of the ST segment termed “the ST hump sign” (STHS) during exercise testing has been associated with resting hypertension and exaggerated blood pressure response to exercise. Objective: We investigated the prevalence and clinical significance of this sign in a population of patients with hypertrophic cardiomyopathy. Methods: Eighty‐one patients with hypertrophic cardiomyopathy (HCM) who underwent cardiopulmonary exercise testing were followed in a retrospective cohort study for a mean period of 5.3 years. Results: The appearance of the STHS at the peak of exercise testing was observed in 42 patients (52%), particularly in the inferior and the lateral leads. Patients with the STHS had higher fractional shortening and maximum left ventricular wall thickness and exhibited more frequently outflow tract gradient >30 mmHg at rest. Furthermore, the presence of STHS was a strong independent predictor of the risk of sudden cardiac death (SCD), as the latter occurred in eight of the patients with this sign (8/42, 19%) and in none of the patients without it (0/39, 0%) (P < 0.001). Conclusion: The appearance of a “hump” at the ST segment during exercise testing appears to be a risk factor for SCD in patients with HCM. However, further studies are necessary to validate this finding in larger populations and to elucidate the mechanism of the appearance of the “hump.”     

Hypertrophic cardiomyopathy and athlete's heart: a tale of two entities

Sudden death during sports activities, although unfrequent,is a tragic event with great impact on both the general andmedical communities. The two commonest conditions leading tosudden cardiac death in young athletes are hyperthrophic cardiomyopathy(HCM), the main cause in the USA, and arrythmogenic right ventricularcardiomyopathy, which is the leading cause in Europe. We report the case of a 17-year-old football player with a pathologicalelectrocardiography (ECG) in the pre-participation screeningprogramme, highly suggestive of HCM, in which ECG study showeda septum thickness of 28 mm. Genetic analysis revealed R 495W mutation in the 18 exon of the MyBPC3 (myosin-binding proteinC) and sports activities were contraindicated. Two years later,septum thickness was 19.5 mm. Usefulness of 12-lead ECG, differentialdiagnosis between athlete's heart and HCM, and the stratificationin patients with HCM are discussed.     

Related factors of dilated cardiomyopathy

Objective To investigate the etiology and relative factors of dilated cardiomyopathy （DCM） in Chinese patients. Methods A case-control study was conducted to compare 233 patients with DCM in high-incidence areas （case group） and 150 patients with stable angina pectoris （control group）. Life styles and history of diseases information was collected by questionaire; human anti-myocardial antibody lgG （AMA- IgG）, human Coxsackie B virus IgG （CBV- IgG） and human adenovirus antibody IgG （ADV- IgG） were measured with ELISA. General chemical and toxicological indicators in drink water from high and low prevalence areas and serum trace elements also were compared. Results 1） Compared with the control group, the case group had more farmers （P 〈 0.01）, with low average incomes （P 〈 0.01 ）, higher alcohol consumption （P 〈 0.01） and higher incidence of the history of myocarditis （P 〈 0.01）. 2） AMA-IgG, CBV-IgG and ADV-IgG levels were low and the positive rates ofAMA-IgG, CBV-IgG and ADV-IgG of patients with DCM were respectively 7.78%, 6.67% and 6.67%, no statistical significance comparing with those in the control group. 3） The content of iron （1.36±2.18 vs 0.39±0.67 rag/L, P〈0.05） and manganese （0.38±0.35 vs 0.15±0.14, P〈0.01） in drinking water of high-incidence areas was significantly higher than that in low-incidence areas. 4） The content of serum iron （69.1±57.8 vs 20.0±17.5 umol/L, P〈0.01 ） and copper （25.7±4.2 vs 19.7±4.5 umol/L, P〈0.01） in the case group evidently exceeded the normal range and obviously higher than that in the control group. Conclusions 1） The incidence of some DCM is related with low incomes, high alcohol consumption and myoearditis. 2） These data do not support that DCM is related with persistent virus infection and autoimmunization; 3） Iron and manganese contents exceeding standards in drinking water and the high content of serum iron and copper is comparatively related with the incidence of DCM.     

Left and right ventricular diastolic dysfunction and diastolic heart failure: does one lead to the other?

Background and Objective Diastolic dysfunction of the left ventricle is a mechanical abnormality diagnosed primarily by echocardiogram, and can be distinguished into three separate degrees based on the severity of reduction in passive compliance and active myocardial relaxation. Methods A literature search was performed for basic science studies, clinical studies and major practice guidelines on the subject of diastolic dysfunction and diastolic heart failure. Important findings were analyzed and correlated with regard to clinical relevance. Results Left ventricular diastolic dysfunction appears to compromise exercise tolerance and is believed to contribute to the pathophysiology in patients with diastolic heart failure. In the clinical setting, however, oftentimes no clear distinction is made between echocardiographically diagnosed diastolic dysfunction and diastolic heart failure, and adequate treatment recommendations are sparse and aimed to prevent worsening and progression of clinical symptoms. To date, there is a lack of high powered trials assessing the possible progression rate from echocardiographically diagnosed diastolic dysfunction to the clinical diagnosis of diastolic heart failure. Furthermore, there are no solid indices to assess the degree of severity of diastolic dysfunction or its progression. Pure right ventricular diastolic dysfunction appears to be even less understood and under-recognized, although it may play a role in the development of both right and left heart failure. Currently there are few but interesting data on the possible interaction between ventricles with diastolic dysfunction and the overall affect on the development of heart failure. Conclusions The timeline and progression of diastolic dysfunction to diastolic heart failure have not been well established and warrant further investigation.     

氧化应激与糖尿病心肌细胞凋亡

氧化应激是糖尿病重要的病理生理过程.氧化应激所导致的心肌细胞凋亡是糖尿病患者非缺血性心力衰竭发生的重要原因.线粒体功能障碍、NADH氧化酶异常以及晚期糖基化终末产物增加是心肌细胞活性氧簇的主要来源.产生的活性氧簇通过直接激活线粒体凋亡途径、肿瘤坏死凶子(TNF)α激活死亡受体途径、P53凋亡途径以及p38丝裂原活化蛋白激酶(MAPK)途径,促进心肌细胞凋亡.但是目前针对糖尿病心脏病的抗氧化治疗效果并不理想,因此有必要进一步研究氧化应激导致心肌细胞凋亡的机制,以发现治疗糖尿病心脏病的新方法.     

扩张型心肌病患者心功能与血清B型利钠肽浓度的关系

目的:研究扩张型心肌病患者B型利钠肽(BNP)与心功能纽约(NYHA)分级的关系.方法:评定114例扩张型心肌病患者的心功能分级,按心力衰竭程度分为3组,测定血清BNP水平,对心功能与BNP水平关系进行观察分析.结果:随着心功能分级的增加,BNP水平上升明显,NYHA Ⅱ～Ⅳ级患者之间血BNP水平差异有统计学意义(P<0.01) .结论:BNP 水平与扩张型心肌病患者心功能分级有明显相关性.     

扩张型心肌病抗心肌抗体的临床观察及其针对性治疗

目的:探讨扩张型心肌病(DCM)的发病机制,观察针对抗心肌抗体进行免疫学治疗的临床疗效和预后.方法:对2001年1月-2007年12月入院治疗的DCM患者(747例)的病史、诊治过程、随访情况进行回顾性分析.结果:747例中抗心肌抗体阳性者527例(70.55%),随访时间为0.9-7.2年,抗心肌线粒体ADP/ATP载体抗体阳性患者(A组)治疗后平均左室舒张末期内径(LVEDd)为(62.53±9.17)mm,左室射血分数(LVEF)为(37.65±11.15)%;抗β1-肾上腺素能受体抗体(抗β1-受体抗体)阳性患者(B组)治疗后LVEDd (61.35±5.68)mm, LVEF (40.65±12.78)%;抗ADP/ATP载体抗体和抗β1-受体抗体均阳性患者(C组)治疗后LVEDd(61.28±7.72)mm, LVEF(38.35±7.05)%.3组与治疗前比较LVEDd差异均有统计学意义(P<0.05)、NYHA心功能分级均改善Ⅰ～Ⅱ级.结论:自身免疫是DCM的常见致病因素,针对抗ADP/ATP载体抗体使用地尔硫和针对抗β1-受体抗体使用美托洛尔治疗DCM均可明显改善患者心脏功能及心室重构,改善预后.