心脏介入性治疗并发心脏压塞的原因分析、诊断与治疗

目的总结心脏介入性治疗过程中发生心脏压塞诊断和处理的经验和教训。方法回顾分析快速性心律失常射频消融术、经皮冠状动脉腔内成形术(PTCA)及支架术以及先天性心脏病封堵术中心脏压塞的临床特点、诊断及处理。结果18例与心脏介入性诊治操作有关的心脏压塞患者,17例为急性心脏压塞,1例在术后72小时延迟出现。18例中9例与射频消融术有关;5例与PTCA有关;3例与先天性心脏病房间隔缺损修补术有关;1例与临时起搏器安装术有关。共有3例死亡。结论心脏介入性治疗可引起即刻和迟缓性两类心脏压塞,多与操作不当有关。及时诊断与处理非常重要,心包穿刺引流是首选方法,必要时应及时切开心包减压或开胸修补。     

Mechanical efficiency of the left ventricle as a function of preload,afterload, and contractility

Summary We have recently shown that the mechanical efficiency of the contractile machinery of the canine left ventricle is constant at 30%–50%, independent of its loading, heart rate, and inotropic conditions. In contrast, the conventional mechanical efficiency of the ventricle is known to vary between 0 and 30%, depending on these conditions. In this study, we derived an equation for the conventional mechanical efficiency as a function of ventricular preload, afterload, and contractility, based on the constant mechanical efficiency of the contractile machinery. In deriving this equation, we fully utilized our new concept of the total mechanical energy of the left ventricle, i.e., systolic pressure-volume area, and our recent findings of the linear relationship between left ventricular oxygen consumption and the systolic pressure-volume area as well as the dependence of this relation on the ventricular inotropic state. As a result, the conventional mechanical efficiency of the left ventricle was found to change between 0 and 25% as an explicit function of these cardiodynamic and inotropic conditions. Using this function, we obtained combinations of loading and inotropic conditions to maximize the conventional mechanical efficiency of the left ventricle.     

Relationship between vectorcardiographic QRSarea, myocardial scar quantification,and response to cardiac resynchronization therapy

Purpose

To investigate the relationship between vectorcardiography (VCG) and myocardial scar on cardiac magnetic resonance (CMR) imaging, and whether combining these metrics may improve cardiac resynchronization therapy (CRT) response prediction.

Function of Isolated Hearts from Septic, Saline-Infused, and Septic, Alcohol-Infused Rats

The aim of the present study was to determine whether hearts that demonstrate depressed myocardial reserves as a result of sustained hypermetabolic sepsis would show a potentiation of the dysfunction after an infusion of high doses of alcohol. We have previously shown that myocardial depression is present in hearts removed from hypermetabolic septic rats. Acute alcohol administration has also been shown to have a negative inotropic effect on the heart. In this study, myocardial function was assessed under in vitro conditions in which preload could be varied and aortic outflow resistance controlled and thus heart function could be determined under both low and high workloads. The alcohol-infused group increased cardiac performance as a function of increasing preload similarly to the controls. Heart rate, however, was significantly elevated compared with control. Isolated hearts from septic, saline-infused animals showed depressed cardiac performance both in terms of stroke volume and myocardial work over a range of preloads. The septic, alcohol-infused animals did not show this depression. Thus, a loss of myocardial reserve was demonstrable in hearts isolated from septic, saline-infused rats but not in septic, alcohol-infused rats. Alcohol, at least acutely, seemed to reverse or ameliorate the loss of myocardial reserve induced by sepsis possibly by increasing the ability of the heart to fill during diastole and thus perform volume work.     

心脏介入治疗患者并发心脏压塞的早期识别抢救及护理

目的探讨心脏介入治疗患者并发心脏压塞的早期识别抢救与护理。方法我院收治的心脏介入治疗并发心脏压塞患者20例,对其临床资料进行回顾性分析。结果经过早期识别与抢救护理,救治成功17例,死亡3例。结论对心脏介入治疗并发心脏压塞的患者,进行早期有效识别和实施积极抢救是非常重要的。完善的术前指导和术中、术后对病情的密切观察为挽救生命赢得了宝贵时间。     

射频导管消融术中心脏穿孔的原因、临床表现和处理

目的 报道8例射频导管消融术中发生的心脏穿孔，总结可能的原因、临床表现和治疗结果。方法 1991年11月至2003年5月，共4323例快速心律失常患者接受射频导管消融治疗。8例患者在消融左侧房室旁路(6例)或阵发性心房颤动(房颤)(2例)的过程发生心脏穿孔，发生率为0．19％。结果 心脏穿孔的原因包括电极导管、房间隔穿刺或消融导管引起冠状静脉窦、心房、左心室或肺静脉破裂。X线透视和超声心动图证实心包积液，7例发生心脏压塞和急性血流动力学恶化。剑突下穿刺心包6例，成功5例并抽出心包积血30～1400mL。2例患者在心包穿刺引流后，仍需外科开胸缝合穿孔。结论 心脏穿孔是射频导管消融术的严重并发症，及时发现和有效救治是十分重要的。     

第20例:临床表现气短、反复晕厥、下肢水肿

<正>患者男性,63岁。因气短、反复晕厥1年6个月,加重伴双下肢水肿1年于2011年11月5日入院。患者于2010年4月出现活动后气短,日常活动略受限。此间反复出现突发倒地,伴意识丧失,无四肢抽搐,可自行缓解,持续时间最长达40 min。1年前活动后气短呈进行性加重,逐渐出现夜间     

Three 4-letter words of hypertension-related cardiac hypertrophy: TRPC, mTOR, and HDAC

Left ventricular hypertrophy due to hypertension represents a major risk factor for adverse cardiovascular events and death. In recent years, the prevalence of cardiac hypertrophy has increased due to obesity and an aging population. Notably, a significant number of individuals have persistent cardiac hypertrophy in the face of blood pressure that is normalized by drug treatment. Thus, a better understanding of the processes underlying the cardiac remodeling events that are set into play by hypertension is needed. At the level of the cardiac myocytes, hypertrophic growth is often described as physiological, as occurs with exercise, or pathological, as seen with hypertension. Here we discuss recent developments in three areas that are fundamental to pathological hypertrophic growth of cardiac myocytes. These areas are the transient receptor potential canonical (TRPC) channels, mammalian target of rapamycin (mTOR) complexes, and histone deacetylase (HDAC) enzymes. In the last several years, studies in each of these areas have yielded new and exciting discoveries into the genesis of pathological growth of cardiac myocytes. The phosphoinositide 3-kinase–Akt signaling network may be the common denominator that links these areas together. Defining the interrelationship among TRPC channels, mTOR signaling, and HDAC enzymes is a promising, but challenging area of research. Such knowledge will undoubtedly lead to new drugs that better prevent or reverse left ventricular hypertension.     

Invasive hemodynamics of constrictive pericarditis, restrictive cardiomyopathy, and cardiac tamponade

Cardiac catheterization historically has been the principal diagnostic modality for the evaluation of constrictive pericarditis, restrictive cardiomyopathy, and cardiac tamponade. In many instances, the hemodynamic consequences of these disorders can be accurately delineated with non-invasive methods. However, cardiac catheterization should be considered when there is a discrepancy between the clinical and non-invasive imaging data, and particularly may be required for the evaluation of patients with complex hemodynamic disorders. This report describes the methods and clinical utility of invasive hemodynamic catheterization for the evaluation of constriction, restriction, and cardiac tamponade.     

原发性高血压患者踝臂指数、肱踝脉搏波传导速度与心脏结构、功能改变的相关性

目的探讨原发性高血压患者踝臂指数(ABI)、肱踝脉搏波传导速度(Ba PWV)与心脏结构、功能改变的相关性。方法收集新疆医科大学第一附属医院干部病房内二科2013年8月~2014年10月符合入选标准的151例高血压患者,询问病史、体检、测血压并进行全自动动脉硬化测试仪(VP-1000)和超声心动图检查及生物化学检测,分别按ABI和Ba PWV分两组:ABI低值组和ABI正常组,Ba PWV增高组和Ba PWV正常组。结果 (1)ABI低值组室间隔厚度(IVST)明显大于ABI正常组(P0.05)。与ABI正常组比较,ABI低值组左心室射血分数(LVEF)、A峰、E峰流速比值(E/A)均明显减低(P0.05)。Ba PWV增高组左心房前后径(LAD)、IVST明显大于Ba PWV正常组(P0.05)。Ba PWV增高组LVEF小于Ba PWV正常组(P0.05)。(2)相关分析显示,ABI与IVST呈负相关(r=-0.769,P0.05),与LVEF、E/A呈正相关(r值分别为0.668、0.566,P0.05)。Ba PWV与LAD、IVST呈正相关(r值分别为0.331、0.474,P0.05),与LVEF呈负相关(r=-0.526,P0.05)。结论 ABI和Ba PWV与原发性高血压患者心脏结构、功能改变呈显著相关,可为临床医生进行尽早干预治疗提供信息。     

Duality of innate stress responses in cardiac injury, repair, and remodeling

The ability of the myocardium to successfully adapt to cardiac injury ultimately determines whether the heart will decompensate and fail, or whether instead it will maintain preserved function. Despite the importance of the myocardial response to cardiac injury, very little is known with respect to the biochemical mechanisms that are responsible for mediating and integrating the stress response in the heart. In the present review we will summarize recent experimental material which suggests that the heart possess a germ-line encoded "innate" stress response that is activated in response to diverse forms of tissue injury. The extant literature suggests that this innate stress response plays an important role in initiating and integrating homeostatic responses within the heart. Nonetheless, as will be discussed further herein, these inflammatory mediators all have the potential to produce cardiac decompensation when expressed at sufficiently high concentrations.     

Diabetic cardiac autonomic neuropathy,inflammation and cardiovascular disease

One of the most overlooked of all serious complications of diabetes is cardiovascular autonomic neuropathy. There is now clear evidence that suggests activation of inflammatory cytokines in diabetic patients and that these correlate with abnormalities in sympathovagal balance. Dysfunction of the autonomic system predicts cardiovascular risk and sudden death in patients with type 2 diabetes. It also occurs in prediabetes, providing opportunities for early intervention. Simple tests that can be carried out at the bedside with real‐time output of information – within the scope of the practicing physician – facilitate diagnosis and allow the application of sound strategies for management. The window of opportunity for aggressive control of all the traditional risk factors for cardiovascular events or sudden death with intensification of therapy is with short duration diabetes, the absence of cardiovascular disease and a history of severe hypoglycemic events. To this list we can now add autonomic dysfunction and neuropathy, which have become the most powerful predictors of risk for mortality. It seems prudent that practitioners should be encouraged to become familiar with this information and apply risk stratification in clinical practice. Several agents have become available for the correction of functional defects in the autonomic nervous system, and restoration of autonomic balance is now possible.     

Adult canine myocytes: isolation, morphology and biochemical characteristics.

A procedure is described for the routine and reproducible preparation of single myocytes from left ventricular tissue of the adult dog. Tissue dissociation was accomplished by repeated incubations of minced ventricle with a mixture of 0.05% trypsin and 0.05% collagenase. Studies by light microscopy and by transmission and scanning electron microscopy indicated that myocytes were cleanly separated at their lateral borders and at the intercalated discs. The intercalated discs retained structural characteristics observed in undissociated tissue and gave the appearance of hemidesmosomes. Approximately 60 to 90% of the cells were typical spindle-shaped myocytes and, of these, up to 80% initially exhibited contractile activity. However, since the cells do not depolarize spontaneously, contractile activity decreased within 1 h, and the myocytes remain quiescent unless stimulated by additions of Ca²⁺, ouabain or epinephrine. The specific activities of Mg²⁺-inhibited ATPase, creatine phosphokinase, hexokinase and isocitrate dehydrogenase in isolated myocytes were comparable to the levels in undissociated ventricular tissue. However, the level of glucose-6-phosphate dehydrogenase, which is low in intact tissue, was not measurable in myocytes.Canine myocytes metabolized glucose with kinetics for uptake and oxidation comparable to that obtained by intact organ perfusion. Furthermore, glucose oxidation was doubled when cells were incubated in the presence of insulin. Fatty acid oxidation was linear following an initial lag phase, and this was insensitive to extracellular carnitine. Canine myocytes demonstrated the ability to oxidize to extracellular leucine and linearly incorporated the amino acid into trichloroacetic acid-precipitable protein.     

Evaluation of ventricular repolarization features with Tp-e,Tp-e/QTc,JTc and JTd during electroconvulsive therapy

Objective

The purpose of this study was to investigate the influence of electrical stimulation transmitted through the body during electroconvulsive therapy on traditional and relatively new ventricular repolarization parameters (Rate corrected QT interval (QTc), QT dispersion (QTd), rate corrected JT interval (JTc), JT dispersion (JTd), T-peak to T-end interval (Tp-e) and Tp-e/QTc ratio) under propofol anaesthesia.