老年心肌病诊治原则与经验

老年心肌病中以扩张型心肌病最为常见.临床主要表现为充血性心力衰竭,常合并有不同类型的心律失常.扩张型心肌病在老年人群主要应与以下情况相鉴别:(1)高血压性心脏病:有明确的高血压病史,超声心动图示有左室肥厚.而扩张型心肌病无高血压史,心脏扩大,而无心肌肥厚.     

扩张型心肌病免疫病理学发病机制研究进展

扩张型心肌病是由多种致病因素引发的严重危害公众健康的心脏疾病,患者常因心脏组织损伤和异常重构而导致慢性心力衰竭。最近的研究提示：许多致病原如病毒、药物等可以引起心脏局部炎症反应和组织损伤,而受损组织释放损伤相关分子模式分子,通过模式识别受体如Toll样受体的介导参与扩张型心肌病的发病。发现并探讨相关损伤相关分子模式分子造成心脏损伤和心室异常重构的免疫病理学机制可以为探索扩张型心肌病新的诊疗策略提供理论依据。     

2019 HRS关于致心律失常性心肌病评估、危险分层及管理专家共识

致心律失常性心肌病是指不是由于缺血性、高血压性或瓣膜性心脏病所引起的可以导致心律失常的心肌异常。它包含了遗传性、全身性、感染性及炎症性疾病的较宽疾病谱,具体包括但不限于以下疾病:致心律失常性右室/左室心肌病、心脏淀粉样变性和结节病、南美锥虫病以及左室致密化不全。致心律失常性心肌病的表型与其它心肌病有重叠,特别是伴有心律失常表现的扩张型心肌病(可有心室扩张和[或]收缩功能受损)。这个专家共识为临床医生提供了对致心律失常性心肌病的评估和管理的指南以及关于遗传学和疾病机制的临床相关信息。每项建议都采用ACC和AHA制定的推荐等级和证据水平的方式表示。     

68例大心脏移植的受体心脏病理学特征分析

目的:分析原发性扩张型心肌病、冠心病、高血压性心脏病及糖尿病心肌病的终末期临床与病理学特点,探讨病理形态学对上述疾病鉴别诊断的价值。方法:以2007年6月至2016年6月期间,本院收治的68例终末期有扩张表现的心脏移植心肌疾病患者为研究对象,将他们分为四组:扩张型心肌病组;冠状动脉粥样硬化性心脏病组;高血压性心脏病组;糖尿病心肌病组。对其临床资料进行回顾性分析;观察移植受体心脏的大体病理改变,并采用H&E染色,Masson、PTAH、天狼猩红等组织化学染色,SMA、Desmin、CD31、CD34等免疫组织化学染色,对移植受体心脏左心室心肌组织进行组织病理学观察。结果:(1)缺血性心肌病组及糖尿病心肌病组的发病年龄明显高于扩张型心肌病组,P=0.0003及P=0.02。与扩张型心肌病组相比,高血压心脏病组的室间隔厚度(1.59±0.09)cm及心脏重量(582.7±38.29)g明显高于扩张型心肌病组(室间隔平均厚度(1.30±0.07)cm;心脏重量(430.7±26.06)g,P=0.03及P=0.0003。(2)四组显微镜下观察发现:扩张型心肌病的主要病理改变是心肌细胞呈退行性变,主要表现心肌细胞颗粒状变性,可见肌丝断裂、溶解消失,心肌间质水肿,心肌间质反应性纤维化。缺血性心肌病的主要病理改变是:可见心肌梗死、坏死周围出现肉芽组织及纤维瘢痕灶及替代性心肌纤维化,间质常可见淋巴、浆细胞浸润。高血压心脏病的主要病理改变是:心肌纤维排列规则,部分心肌细胞肥大,核大、畸形;心肌间质纤维化明显;心肌内,尤其是室间隔心肌组织内常见小冠状动脉管壁增厚。糖尿病心肌病的主要病理改变是:心肌细胞可出现散在性微小坏死灶,心肌间质和血管周围明显纤维化,可见心肌间小冠状动脉管壁增厚,基底膜增厚。(3)天狼猩红染色观察发现终末期心脏病心肌纤维化中胶原纤维主要为Ⅰ型及Ⅲ型胶原纤维,并且Ⅰ型胶原纤维的数量多于Ⅲ型。(4)免疫组化结果发现SMA染色阳性、Desmin染色阴性的肌纤维母细胞数目增多。结论:(1)病理形态学在扩张型心肌病与缺血性心肌病、高血压心脏病及糖尿病心肌病鉴别诊断中有一定意义。(2)心脏扩大前1~5年有高血压病史,出现明显室间隔肥厚,心肌间质明显纤维化及心肌间质小血管壁增厚常常提示诊断高血压心脏病。(3)心肌内微小血管壁增厚及基底膜增厚、血管周心肌纤维化是糖尿病心肌病主要的病理形态学特点,对糖尿病心肌病的诊断有重要意义。(4)肌纤维母细增生可能是终末期心脏病心肌纤维化发生中一种关键的病理因素。     

Tribbles同源蛋白3参与糖尿病性心肌病的机制探讨

糖尿病可以独立于高血压、心脏瓣膜疾病、冠心病等其他心脏病因素之外,导致心脏结构和功能的异常,引起糖尿病性心肌病。Tribbles同源蛋白3是肥胖、糖尿病和动脉粥样硬化等代谢性疾病的关键性枢纽蛋白,可以通过胰岛素抵抗、内质网应激、脂质代谢等一系列途径,促使糖尿病并发症的形成。     

非缺血性心脏病患者应用β受体阻滞剂T波电交替的变化

T波电交替(TWA)是指T波振幅随心脏搏动发生周期性改变，是致死性室性心律失常的预测指标。据报道非缺血性心脏病(NIHD)患者在TWA阳性时^123I—MIBG心肌显像异常，而扩张型心肌病(DCM)患者应用β受体阻滞剂后，随着左室射血分数(LVEF)的提高，TWA消失。该实验     

中西医结合治疗扩张型心肌病1例报道

正扩张型心肌病(dilated cardiomyopathy,DCM)是一种出现左室或双室扩大、收缩功能障碍,但没有存在其他负荷异常(高血压、瓣膜病)或冠状动脉病变造成的整体收缩功能损害的心肌疾病。本研究报道1例扩张型心肌病伴终末期难治性心力衰竭病例,在西医常规利尿、拮抗神经内分泌活性、扩血管、强心等药物对症治疗后症状未见明显缓解,予植入心脏再同步化并     

扩张型心肌病的离子通道发病机制研究进展

扩张型心肌病是一侧或双侧心腔扩大、心肌收缩功能障碍为主要特征的心肌疾病。其发病机制可能与病毒感染、免疫反应以及遗传因素有关。近年来研究发现心脏钠通道基因突变可导致扩张型心肌病。因此,现重点从心肌细胞离子通道的角度来论述扩张型心肌病的发病机制,探讨其治疗的新靶点。     

脂毒性心肌病的研究进展

心脏中脂质大量积聚,可以引起心脏功能异常,称之为脂毒性心肌病。目前,脂毒性心肌病已在大量的转基因小鼠模型中发现,证明了有心脏毒性的脂质积聚与脂毒性心肌病是相关联的。研究过氧化物酶体增殖剂活化受体在脂毒性心肌病中的作用,可以为预防和治疗脂毒性心肌病提供新思路。     

生长激素治疗扩张型心肌病的初步研究

心脏肥厚是心脏对超负荷的一种生理性代偿反应,扩张型心肌病缺乏这一种代偿反应。生长激素有助于心肌肥厚,故试用于扩张型心肌病患者。 方法 原发性扩张型心肌病7例,符合以下标准:药物治疗后仍有心衰的临床表现,左室舒张末内径超过60mm,射血分数<40％,入选前6个月病情稳定,窦性心律,     

Adiposity of the heart, revisited

Obesity is a major risk factor for heart disease. In the face of obesity's growing prevalence, it is important for physicians to be aware of emerging research of novel mechanisms through which adiposity adversely affects the heart. Conventional wisdom suggests that either hemodynamic (that is, increased cardiac output and hypertension) or metabolic (that is, dyslipidemic) derangements associated with obesity may predispose individuals to coronary artery disease and heart failure. The purpose of this review is to highlight a novel mechanism for heart disease in obesity whereby excessive lipid accumulation within the myocardium is directly cardiotoxic and causes left ventricular remodeling and dilated cardiomyopathy. Studies in animal models of obesity reveal that intracellular accumulation of triglyceride renders organs dysfunctional, which leads to several well-recognized clinical syndromes related to obesity (including type 2 diabetes). In these rodent models, excessive lipid accumulation in the myocardium causes left ventricular hypertrophy and nonischemic, dilated cardiomyopathy. Novel magnetic resonance spectroscopy techniques are now available to quantify intracellular lipid content in the myocardium and various other human tissues, which has made it possible to translate these studies into a clinical setting. By using this technology, we have recently begun to study the role of myocardial steatosis in the development of obesity-specific cardiomyopathy in humans. Recent studies in healthy individuals and patients with heart failure reveal that myocardial lipid content increases with the degree of adiposity and may contribute to the adverse structural and functional cardiac adaptations seen in obese persons. These studies parallel the observations in obese animals and provide evidence that myocardial lipid content may be a biomarker and putative therapeutic target for cardiac disease in obese patients.     

Obesity and the heart

Obesity has been identified as an independent risk factor for coronary heart disease and congestive heart failure. Although congestive heart failure can be secondary to coronary heart disease, in morbid obesity these conditions can be independent. Cardiac structure and function can be altered even in the absence of systemic hypertension and underlying organic heart disease. In obese patients total blood volume increases and creates a high cardiac output state that may cause ventricular dilatation and ultimately eccentric hypertrophy of the left (and possibly the right) ventricle. Eccentric left ventricular hypertrophy produces diastolic dysfunction. Systolic dysfunction may ensue due to excessive wall stress if wall thickening fails to keep pace with dilatation. This disorder is referred to as obesity cardiomyopathy. The frequent coexistence of systemic hypertension in obese individuals facilitates development of left ventricular dilatation and hypertrophy. Congestive heart failure may occur and may be attributable to left ventricular diastolic dysfunction or to combined diastolic and systolic dysfunction. The risk of coronary heart disease seems to be more strictly correlated to central obesity than to increased body mass index. Insulin resistance seems to be the key factor that links obesity and ischaemic heart disease. In such a condition the so called Syndrome X appears. It is characterized by: obesity, systemic hypertension, diabetes mellitus, hypertriglyceridaemia and reduced HDL cholesterol levels. Considering that left ventricular hypertrophy is often present, many risk factors coexist in obese patients. Weight loss is very useful in obese patients. It may reduce mortality and morbidity for coronary heart disease and delay or avoid the appearance of congestive heart failure. It is proved that after weight loss, blood pressure, glucose, cholesterol, triglycerides and left ventricular mass decrease.     

Obesity and cardiac failure

Obesity alone is the cause of 11% of cases of cardiac failure in men and 14% of cases in women in the United States. The frequency of obesity continues to rise in our country, 41% of our compatriots being obese or overweight. It is expected that obesity will become an important cause of cardiac failure in the coming years. The Framingham study showed that, after correction for other risk factors, for every point increase in body mass index, the increase in risk of developing cardiac failure was 5% in men and 7% in women. There are three physiopathological mechanisms to explain the adverse effects of obesity on left ventricular function: an increase in ventricular preload secondary to increased plasma volume induced by the high fatty mass; an increase in left ventricular afterload due to the common association of hypertension generated by activation of the sympathetic nervous system by hyperinsulinism; and systolic and diastolic dysfunction due to changes in the myocardial genome and coronary artery disease induced by risk factors of atherosclerosis aggravated by obesity. The adipocyte also secretes a number of hormones which act directly or indirectly on the myocardium: angiotensin II, leptin, resistin, adrenomedulin, cytokines. These haemodynamic and hormonal changes profoundly modify the genetic expression of the myocardium in obesity, favourising hypertrophy of the myocyte and the development of interstitial fibrosis. Whether it be eccentric in the absence of hypertension or concentric when hypertension is associated with obesity, left ventricular hypertrophy, although normalising left ventricular wall stress, has adverse consequences causing abnormal relaxation and decreased left ventricular compliance. Therefore, in obese patients, two forms of cardiac failure may be observed. The more common is due to diastolic dysfunction, obesity being one of the principal causes of cardiac failure with preserved systolic function. Cardiac failure due to systolic dysfunction is less common and may be observed in cases with inappropriate left ventricular hypertrophy which does not normalise abnormal left ventricular wall stress leading to cardiomyopathy, and in cases with associated coronary artery disease. Whatever the underlying mechanism, the diagnosis of cardiac failure is made more difficult by obesity. From the prognostic point of view, in the global population of patients with cardiac failure, obesity improves survival because it counteracts the adverse effect of cachexia; however, obesity increases the risk of sudden death. In fact, obesity is associated with dynamic change in QT interval. In cases of cardiac failure secondary to obesity-related cardiomyopathy, loss of weight leads to an improved functional status and a reduction of left ventricular remodelling and an increase of the ejection fraction.     

Myocardial catecholamines in hypertrophic and dilated (congestive) cardiomyopathy: a biopsy study

A high performance liquid chromatographic method was used to determine myocardial norepinephrine and epinephrine concentrations in 66 biopsy specimens obtained from the right or left ventricle during routine diagnostic cardiac catheterization of 45 patients with dilated (congestive) or hypertrophic cardiomyopathy, or with heart disease other than cardiomyopathy, such as acute perimyocarditis, postmyocarditis and constrictive pericarditis. The validity of catecholamine determination in a 2 to 6 mg biopsy specimen to assess overall ventricular myocardial catecholamines was demonstrated. Norepinephrine concentrations in the myocardium were inversely correlated with the grade of hypertrophy in patients with congestive cardiomyopathy or heart disease other than cardiomyopathy, but not in patients with hypertrophic cardiomyopathy. The fact that the myocardial norepinephrine concentration was always lower in the left than in the right ventricle of the same patient may be explained by the simple dilution of sympathetic nerve endings in the left ventricle. There were some cases of hypertrophic cardiomyopathy in which the concentration of myocardial norepinephrine was exceptionally high, although its mean value was not significantly higher than that in patients with other types of heart disease who served as a control group without cardiomyopathy. Some patients with dilated cardiomyopathy had lower levels of myocardial norepinephrine than would be expected for the degree of interstitial fibrosis and the severity of heart failure. The mean plasma norepinephrine and epinephrine levels were significantly elevated in patients with dilated cardiomyopathy.     

MR-tomography of the heart in cardiomegaly caused by dilated cardiomyopathy and ischemic heart disease]

The paper deals with the results of magnetic resonance cardiac tomography in 19 patients with dilated cardiomyopathy and 10 patients with coronary heart disease who had severe cardiomegaly and congestive heart failure symptoms. Magnetic resonance tomography showed that the patients with dilated cardiomyopathy exhibited profound dilatation of all the 4 cardiac cavities and a chaotic pattern of impaired segmental left ventricular contractility, whereas those with coronary heart disease had predominant dilatation of the left cavity and local myocardial dysfunctions. Magnetic resonance may be one of the non-invasive tools which make the genesis of cardiomegaly clear in patients with heart failure.     

Symptomatic left ventricular dysfunction and Behçet disease. Report of 2 cases

Beh?et's disease is associated with cardiac complications which may affect all three cardiac layers in 1 to 6% of cases. Although pericardial and coronary disease are the most common, the myocardium may also be affected. The clinical presentation may be left ventricular dysfunction with signs of dilated cardiomyopathy. The cause of the left ventricular dysfunction is usually coronary artery disease but it can also be inflammatory, resulting in a myocarditis with normal coronary arteries. The authors report two cases of Beh?et's disease with symptomatic left ventricular dysfunction presenting as dilated cardiomyopathy with normal coronary arteries in one of the cases. Recent echocardiographic studies suggest that the incidence of myocardial disease is underestimated in this pathology: 20 to 35% of patients with Beh?et's disease but no cardiac symptoms had left ventricular diastolic dysfunction. A more attentive investigation of left ventricular diastolic function in these patients should enable earlier diagnosis of this complication.     

A case of massive dystrophic cardiac calcinosis with increased bone resorption markers: a novel pathophysiologic link?

We report a 72-year-old man who presented to our emergency room with congestive heart failure that was resistant to initial medical therapy. He had suffered from anterior myocardial infarction 20 years prior. Echocardiography and computed tomography revealed marked cardiac calcification including myocardium, chordal structures, mitral annulus, and aortic valve. Neither chronic renal insufficiency nor hypercalcemia were present in our patient. Bone resorption markers were increased and bone mineral density was consistent with severe osteoporosis. We suggested a novel mechanism, that increased bone resorption may lead to accumulation of calcium into avascular tissues in the heart (ie, chordal structures, mitral annulus, aortic valve, and fibronecrotic myocardium) especially in the setting of high left ventricular end-diastolic pressure. Dystrophic cardiac calcinosis, an age-related cardiomyopathy, is associated with elevated bone resorption markers and it may cause alterations in cellular calcium hemostasis with initiation of deleterious events leading to aggravate dilated and restrictive cardiomyopathy and may result in intractable congestive heart failure. The implication of this case report needs to be reemphasized.     

Obesity cardiomyopathy: pathogenesis and pathophysiology

Obesity is becoming a worldwide phenomenon. Myocardial changes associated with the obese state are increasingly recognized, independent of hypertension, obstructive sleep apnea and coronary artery disease. The existence of a cardiomyopathy of obesity is supported by a range of evidence: epidemiologic study findings, which have shown an association between obesity and heart failure; clinical studies that have confirmed the association of adiposity with left ventricular dysfunction, independent of hypertension, coronary artery disease and other heart disease; and experimental evidence of structural and functional changes in the myocardium in response to increased adiposity. The most important mechanisms in the development of obesity cardiomyopathy are metabolic disturbances (insulin resistance, increased free fatty acid levels, and also increased levels of adipokines), activation of the renin-angiotensin-aldosterone and sympathetic nervous systems, myocardial remodeling, and small-vessel disease (both microangiopathy and endothelial dysfunction). In the first part of this two-part Review, we seek to evaluate the emerging evidence for the existence of a cardiomyopathy of obesity and clarify the responsible mechanisms.     

Obesity and cardiac performance

In association with consistent increases in stroke volume and a high incidence of systemic and/or pulmonary arterial hypertension, the cardiac work of very obese patients at rest was considerably greater than that predicted for normotensive subjects at ideal body weight. Although this change was effected chiefly by increased left ventricular work, and the latter was roughly correlated with the amount of excess body weight, variable increases in right ventricular work resulted in a lack of correlation between total cardiac work and the amount of excess weight.

Though pulmonary hypertension secondary to an increase in left ventricular filling pressure usually occurred in the very obese patients of this series under conditions of moderate exercise, the increment in cardiac output per unit increment in oxygen consumption with exercise was within normal limits. Because of the need to move excess body weight, at any given level of activity the cardiac workload was considerably greater for the obese subjects than for individuals at ideal body weight.

Cardiac enlargement and increased heart weight were found quite regularly in very obese subjects, increasing in rough proportion to the amount of excess body weight. The increased heart weight was due to muscular hypertrophy involving the left ventricle or both the left and right ventricles. Neither fatty infiltration of the myocardium nor isolated right ventricular hypertrophy was observed.

Cardiac failure occurred in 8 per cent of the extremely obese patients in this series, involving a high cardiac output and left ventricular or biventricular insufficiency. It has been proposed that myocardial hypertrophy and failure derive from the increased cardiac workload present at rest and during exercise. Heart failure due to obesity generally responded well to bed rest, digitalis, diuretics, dietary sodium restriction and measures usually effective in managing heart failure due to other causes. Effective long term therapy necessarily involved weight reduction.     

Obesity cardiomyopathy: pathophysiology and evolution of the clinical syndrome

Obesity produces an increase in total blood volume and cardiac output because of the high metabolic activity of excessive fat. In moderate to severe cases of obesity, this may lead to left ventricular dilation, increased left ventricular wall stress, compensatory (eccentric) left ventricular hypertrophy, and left ventricular diastolic dysfunction. Left ventricular systolic dysfunction may occur if wall stress remains high because of inadequate hypertrophy. Right ventricular structure and function may be similarly affected by the aforementioned morphologic and hemodynamic alterations and by pulmonary hypertension related to the sleep apnea/ obesity hypoventilation syndrome. The term obesity cardiomyopathy is applied when these cardiac structural and hemodynamic changes result in congestive heart failure. Obesity cardiomyopathy typically occurs in persons with severe and long-standing obesity. The predominant causes of death in those with obesity cardiomyopathy are progressive congestive heart failure and sudden cardiac death.