Advances in Imaging of the Cardiac Neuronal System

Left ventricular ejection fraction (LVEF) is a useful tool for stratifying risk for heart failure progression and life-threatening arrhythmic events. Yet, the clinical course of heart failure patients with severely reduced LVEF is variable, and the majority of patients who die suddenly do not have an LVEF ≤35%. A recently completed large multicenter trial, ADMIRE-HF, confirms that cardiac neuronal imaging with I-123 metaiodobenzylguanidine is an important independent predictor of heart failure progression and sudden cardiac death. Data from that study indicate that heart failure patients with severe impairment of cardiac sympathetic innervation are at highest risk for heart failure progression, heart failure patients with moderate impairment of sympathetic innervation are at highest risk for life-threatening arrhythmic events, and heart failure patients with preserved sympathetic innervation are at low risk for either death due to heart failure progression or sudden cardiac death.     

Cognitive impairment and congestive heart failure

BACKGROUND: The course of heart failure can be unpredictable and uncontrolled symptoms are the main problem. This review analyses the current literature surrounding cognitive impairment and heart failure with special emphasis on self-management and quality of life. It attempts to explain the extent to which compliance and self-management contribute to acute hospitalisation, and to what extent the patient's mental capability influences compliance with treatment. CONCLUSION: The literature identifies a link between congestive heart failure and cognitive impairment.     

脑梗死急性期合并心衰血压调控策略

目的探讨脑梗死急性期合并心衰血压调控的标准及方法。方法收集100例发病在24h内的急性脑梗死合并心力衰竭（心功能Ⅱ-Ⅳ级）的患者资料，并随机分为硝普钠治疗组和对照组。全部患者在入院时均进行美国国立卫生院神经功能缺损评分、TCD检查。两组患者的发病年龄、血压增高程度、神经功能缺损评分、TCD改变以及心衰程度差异无统计学意义（P〉0.05）。结果心功能Ⅱ级患者血压控制对心衰有益，但却严重影响脑血流灌注。与对照组相比脑血流动力学受损明显。心功能Ⅲ-Ⅳ级患者经合理控制血压，心功能改善后脑血流灌注较对照组有明显改善。结论脑梗死急性期合并心衰合理调控血压，无论对心功能的改善抑或脑血流动力学和神经系统临床症状的好转都是十分有益的。     

Overcoming Electromagnetic Interference by LVADs on ICD Function by Shielding the ICD Programmer Wand and Extension Cable

Patients with end-stage cardiomyopathy and congestive heart failure are increasingly undergoing implantation with left ventricular assist devices (LVADs). In addition, implantable cardioverter-defibrillator (ICD) therapy has been proven to be an important part of the treatment for cardiomyopathy/congestive heart failure. Previous reports have noted a potential and dramatic electromagnetic interference from LVADs on ICDs that cause impaired telemetry communication between the ICD and ICD programmer. Such interference has necessitated explantation and generator replacement in order to resume communication between the ICD and programmer. We report two patients with advanced congestive heart failure and ICD programming impairment caused by a HeartMate II LVAD (Thoratec Corporation, Pleasanton, CA, USA) that was overcome by placing aluminum shielding around the ICD programmer wand and steel shielding around the extension cable during ICD interrogation.     

Heart failure with preserved LV function: pathophysiology, clinical presentation, treatment, and nursing implications

The syndrome of congestive heart failure occurring secondary to diastolic dysfunction accounts for the major pathophysiologic mechanism in up to one-third of patients who present with dyspnea on exertion and pulmonary congestion. Diastolic dysfunction is characterized by an alteration in the normal diastolic pressure-volume relationship while systolic function may be normal. It is manifested by impairment in the left ventricle's ability to relax and fill completely during diastole at normal low ventricular pressures. This subset of heart failure is most commonly associated with concentric left ventricular hypertrophy and ischemic states. Symptom presentation is similar to that associated with systolic dysfunction as are rates of rehospitalization. Diagnosis is made based on data obtained from invasive and noninvasive procedures. Unlike in the setting of systolic dysfunction, however, there are no large-scale randomized clinical trials evaluating drug efficacy that could be used to guide treatment for the management of diastolic dysfunction. Treatment recommendations, therefore, are empiric. Identifying and aggressively treating potentially reversible causes is a priority. Many of the same drugs used in the management of heart failure associated with systolic dysfunction are also used in the setting of diastolic impairment; however, dosages and rationale for administration may differ. Nursing interventions too are similar. Monitoring response to medications, especially in the acute setting, and comprehensive patient education are paramount. Much is yet to be learned about the management of diastolic dysfunction.     

Relationship between myocardial remodeling and neurohumoral activation in patients with cardiac failure

50 healthy subjects and 685 patients with heart failure (NYHA functional class I-IV) due to coronary heart disease (CHD) aged 34-74 years (mean age 48.1 +/- 8.22 years) were examined. Cardio-hemodynamics was assessed by M- and B-echocardiography from parasternal, subcostal and apical view on a short and long axis with transmitral Doppler. Plasma levels of epinephrine, norepinephrine, serotonin, aldosterone, STH, hydrocortisone were measured in the patients. Progression of cardiac failure is characterized by evolution of the left ventricular ellipse form into a ball shape primarily due to an increase in cross sectional cavity size. The changes of the left ventricular geometry in heart failure patients are combined with progressive reduction of the relative wall thickness index, intensification of the myocardial stress and impairment of diastolic function. The clearest intercoupling between myocardial remodeling and neurohumoral activation was registered in patients with asymptomatic heart failure. With growing severity of left ventricular dysfunction, plasm activity of serotonin, hydrocortisone and aldosterone increase more than levels of norepinephrine, epinephrine and STH.     

Alterations in the peripheral circulation in patients with mild heart failure.

OBJECTIVE: In patients with severe heart failure, compensatory mechanisms fail to provide adequate blood supply to the peripheral circulation, especially when the metabolic need is increased. The aim of this study was to assess alterations in the peripheral circulation in patients with mild heart failure using ultrasound Doppler. METHODS: In 19 controls and in 11 patients with mild heart failure, Doppler spectra were recorded from the carotid, the brachial and the femoral artery at rest and, from the latter two arteries, during post-occlusive reactive hyperemia. Parameters derived from these Doppler spectra were used to make comparisons between both groups. RESULTS: At rest, the duration of the acceleration of blood was shorter in controls, the acceleration was steeper in controls and the deceleration duration was longer in controls as compared to the patients. Differences in the response to reactive hyperemia were only observed in the common femoral artery. CONCLUSIONS: In patients with mild heart failure, significant alterations in the peripheral circulation were observed especially for the femoral artery. These changes are caused by the impairment of the left ventricular function and by adjustments in the compensatory mechanism of the peripheral circulation.     

慢性心功能衰竭患者认知功能对自我护理的影响

目的探讨慢性心功能衰竭患者认知功能对自我护理的影响,识别认知受损的患者,以期引起护理人员对慢性心功能衰竭患者认知功能的关注,为优先对认知受损患者提供实施延续性护理服务提供依据。方法对北京阜外心血管病医院慢性心功能衰竭监护病房及内科重症监护病房的152例住院慢性心功能衰竭患者,使用蒙特利尔认知功能评估表和心功能衰竭自我护理指数量表进行调查。结果以24分为界值,发现21.3%的患者伴认知功能损伤;其中延迟回忆、语言、视空间与执行功能维度受损较严重;多元线性回归分析结果显示,年龄、心功能分级、抑郁状况及认知功能对自我护理维持变异的解释度为30.1%,其中认知功能占21.5%;认知功能对自我护理管理及自我护理信心变异的解释度分别为29.2%和36.5%。结论慢性心功能衰竭患者的认知功能影响了其自我护理,医务人员在临床工作中应识别认知受损的慢性心功能衰竭患者并对其优先实施延续性护理。     

Factors associated with quality of life in Arab patients with heart failure

The aim of this study was to examine the relationships of demographic characteristics, medical variables and perceived social support with quality of life (QOL) in Arab patients with heart failure. A cross‐sectional study was conducted to identify factors associated with QOL in Arab patients with heart failure. Participants with heart failure (N = 99) were enrolled from a nonprofit hospital and an educational hospital. Data were collected on QOL using the Short Form‐36 survey. Perceived social support was measured with the Medical Outcomes Study Social Support Survey. The majority of the patients reported significant impairment in QOL as evidenced by subscale scored. Left ventricular ejection fraction was the strongest correlate of most QOL domains. Tangible support was significantly associated with most QOL domains. Other social support dimensions were not significantly related to QOL domains. Most patients with heart failure had significant disrupting pain and limitations in performing activities which interfered with their usual role. Due to the importance of understanding QOL and its determinants within the context of culture, the outcomes of this study may provide valuable guidance to healthcare providers in Arabic countries as well as Western society in caring for these patients. Further studies are needed to explore the relationship between social support and QOL among patients with heart failure in the Arabic culture.     

Assessment of cognitive function in heart failure patients.

BACKGROUND: Research on the cognitive capacity of heart failure patients is limited, with a paucity of benchmark information available for this population. It is highly likely that cognitive deficits affect patients' understanding of disease and treatment requirements, as well as limiting their functional capacity and ability to implement treatment plans, and undertake self-care. AIMS: The purpose of this study was to establish a comprehensive neurocognitive profile of the heart failure patient through systematic neurocognitive assessment and to determine whether an association existed between severity of heart failure and cognitive abilities. METHODS: Thirty-eight patients were recruited from the heart failure patient databases of two metropolitan hospitals in Melbourne, Australia. Participants were individually assessed using four standardised, internationally recognised neuropsychological tests that examined current and premorbid intelligence, memory and executive functioning. RESULTS: Although there was no significant decline from premorbid general intellectual function, other specific areas of deficit, including impaired memory and executive functioning, were identified. There were no significant correlations between heart failure severity and the neurocognitive measures used. CONCLUSION: The results support the need to recognise cognitive impairment in people with heart failure and to develop an abbreviated method of assessing cognitive function that can be easily implemented in the clinical setting. Identifying cognitive deficits in this population will be useful in guiding the content and nature of treatment plans to maximise adherence and minimise worsening of heart failure symptoms.     

Cardiac resynchronization therapy in mildly symptomatic heart failure: the earlier the better

A new era is emerging in the field of complex pacing as a treatment for heart failure. Cardiac resynchronization therapy (CRT) is already established as an effective therapy to improve mortality and functional capacity in patients with moderate-severe heart failure, left ventricular systolic impairment and conduction delay (prolonged QRS duration on surface ECG). Recent evidence has demonstrated that CRT is also an effective treatment for patients with mild heart failure. As the indications for CRT expand, cardiologists face the exciting prospect of exploring where pacemaker technology can help improve patient outcomes across the entire heart failure disease continuum. Enthusiasm for future application needs to be tempered with the practicalities of delivering safe and effective care within the confines of finite healthcare resources.     

Cardiac resynchronization therapy in mildly symptomatic heart failure: the earlier the better

A new era is emerging in the field of complex pacing as a treatment for heart failure. Cardiac resynchronization therapy (CRT) is already established as an effective therapy to improve mortality and functional capacity in patients with moderate–severe heart failure, left ventricular systolic impairment and conduction delay (prolonged QRS duration on surface ECG). Recent evidence has demonstrated that CRT is also an effective treatment for patients with mild heart failure. As the indications for CRT expand, cardiologists face the exciting prospect of exploring where pacemaker technology can help improve patient outcomes across the entire heart failure disease continuum. Enthusiasm for future application needs to be tempered with the practicalities of delivering safe and effective care within the confines of finite healthcare resources.     

Caring for infants with congenital heart disease and their families

Congenital heart defects are classified into two broad categories: acyanotic and cyanotic lesions. The most common acyanotic lesions are ventricular septal defect, atrial septal defect, atrioventricular canal, pulmonary stenosis, patent ductus arteriosus, aortic stenosis and coarctation of the aorta. Congestive heart failure is the primary concern in infants with acyanotic lesions. The most common cyanotic lesions are tetralogy of Fallot and transposition of the great arteries. In infants with cyanotic lesions, hypoxia is more of a problem than congestive heart failure. Suspicion of a congenital heart defect should be raised by the presence of feeding difficulties in association with tachypnea, sweating and subcostal recession, or severe growth impairment. Follow-up of infants with congenital heart disease should follow the schedule of routine care for healthy babies with some modifications, such as administration of influenza and pneumococcal vaccines. More frequent follow-up is required if congestive heart failure is present. Family psychosocial issues should also be addressed. One of the main roles for the family physician is to help the parents put the diagnosis in perspective by clarifying expectations and misconceptions, and answering specific questions.     

慢性心衰-心肾综合征及生物标志物

慢性心衰不仅是一种疾病诊断,更是一种复杂的临床综合征,在合并慢性肾病尤其是终末期肾病患者中,心衰发病率增加是死亡的主要原因。心脏和肾脏之间存在密切而复杂的关系(即所谓"心肾综合征"),心衰患者一旦合并慢性肾病或肾损伤均显示预后不良。因而,对于这类高风险患者应予以早期诊断并积极干预治疗。一些标志物已被证明在心血管疾病的诊断和预后评价中具有新的、重要的作用,由于其与慢性心衰-心肾综合征具有密切关系而备受关注,具有高度敏感性和特异性的生物标志物成为近年来研究的热点。     

A feeling in the waters: diagnosis of heart failure using urinary natriuretic peptides

Plasma levels of brain natriuretic peptide (BNP) and N-terminal pro-BNP (N-BNP) are highly sensitive markers of ventricular dysfunction and/or hypertrophy and, in established disease, offer prognostic value and may be useful for guidance of therapy. Ng and co-workers report in this issue of Clinical Science that urinary levels of N-BNP may be as useful as plasma levels for the discrimination of patients with and without heart failure. This raises the potential for a relatively simple urine test that could be used for the diagnosis of heart failure. Roles in prognostication and the guidance of therapy may also be possible but, perhaps of most significance, measurement of urinary N-BNP may be applied to screening of patients at high risk of heart failure. The main limitations of the study were that the sample of heart failure patients comprised only 34 individuals with New York Heart Association functional Class IV and that the observed correlation between levels of urinary N-BNP and plasma creatinine seemed counter-intuitive. The latter issue needs clarification, as renal impairment is a frequent co-morbidity among patients with heart failure and will potentially confound any observed association between ventricular dysfunction and urinary N-BNP levels. Another caveat is that it is unclear if testing for urinary N-BNP can be cheaply and conveniently administered on a large scale. Nevertheless, this first demonstration of elevated N-BNP in the urine of patients with heart failure raises a number of exciting possibilities with regard to the management of patients with established or possible heart failure. Further investigation is required and eagerly awaited.     

Valsartan in chronic heart failure

OBJECTIVE: To evaluate the evidence for valsartan in the treatment of heart failure and determine its need for formulary inclusion. DATA SOURCES: OVID and PubMed databases were searched (1983-June 2004) using the key words angiotensin-receptor blocker, heart failure, valsartan, Diovan, and angiotensin-converting enzyme inhibitor. Only English-language literature was selected. STUDY SELECTION AND DATA EXTRACTION: Pharmacology and pharmacokinetic evaluations for valsartan were selected. Prospective, randomized clinical trials investigating the use of valsartan and other angiotensin-receptor blockers (ARBs) in chronic heart failure were evaluated. DATA SYNTHESIS: Valsartan, a selective antagonist for angiotensin receptor subtype 1, is the first ARB to be approved for use in chronic heart failure. Clinical trial data support valsartan as an alternative to angiotensin-converting enzyme (ACE) inhibitors in ACE inhibitor-intolerant patients with chronic heart failure. Valsartan is generally well tolerated, with renal impairment, elevated serum creatinine and potassium levels, and dizziness being the most common adverse effects; consequently, patients experiencing those adverse events while taking ACE inhibitors are likely to experience them with valsartan. Although further study is needed, differences in effectiveness among races may exist with use of valsartan; however, at this time, valsartan is recommended as an alternative to ACE inhibitors regardless of race. Candesartan and losartan have been studied in similar settings. Candesartan's data support its use in heart failure; however, losartan's data have been less consistent. CONCLUSIONS: Valsartan is a safe and effective alternative for heart failure patients intolerant of ACE inhibitors. Valsartan has not been shown to be safe and effective when used in combination with ACE inhibitors.     

Left stellate ganglion block has only small effects on left ventricular function in awake dogs before and after induction of heart failure. (Institut für Klinische Anaesthesiologie, Heinrich-Heine-Universität, Düsseldorf, Germany) Anesth Analg 2000;91:787–792.

This study investigated the effects of left stellate ganglion block (LSGB) in chronically instrumented awake dogs before and after the induction of pacing-induced congestive heart failure. Twelve dogs were instrumented for measurement of global hemodynamics (LV pressure [LVP]), its first derivative, cardiac output (CO), and regional myocardial function (systolic posterobasal, segment length shortening, mean velocity [SLmv]). Before the induction of heart failure, LSGB did not affect CO and SLmv, but slightly reduced LVP. Conclude that even during heart failure the hemodynamic changes after LSGB are small, confirming a broad margin of safety.
Comment by James E. Heavner, D.V.M., Ph.D. The outcomes of this very nice animal study should provide some comfort to clinicians that perform stellate ganglion blocks on patients with a history of heart failure. In chronically instrumented animals, left stellate ganglion block had minimal affect on cardiac function either before or after heart failure had been induced. However, caution should always be exercised in extrapolating animal data to humans. In this regard, the investigators point out that in healthy humans, an impairment of left ventricular relaxation can be seen after left stellate ganglion block. They further caution that patients with acute heart failure in whom the response to changes in sympathetic tone is maintained, may be more susceptible to the adverse effects of left stellate ganglion block on cardiac dynamics.     

Plasma levels of N-terminal proatrial natriuretic peptide in children are dependent on renal function and age

Plasma levels of natriuretic peptides are used as diagnostic markers of heart failure. The aim of this study was to analyse the relation between plasma levels of N-terminal proatrial natriuretic peptide (Nt-proANP) and renal function, and to develop reference values in children. Nt-proANP was measured in the plasma of 86 patients whose glomerular filtration rate (GFR) was determined by use of the X-ray contrast medium iohexol and a fluorescence technique. Blood samples for Nt-proANP were also collected in 399 reference children, aged 0 - 15 years. The relationship between Nt-proANP and GFR was examined using a multiple regression analysis. The mean value of Nt-proANP was markedly higher in children with heart failure than in children with malignant or urologic diseases (p<0.001). The variability in plasma levels of Nt-proANP was mainly (adjusted R2=0.81) explained by the following four variables: presence of heart failure, GFR, age and previous treatment with anthracyclins. Plasma levels of the peptide are raised at birth, but fall rapidly to adult levels. We conclude that the plasma levels of Nt-proANP are age-dependent. Moderately elevated values were registered in children with severe renal impairment. Heart failure is regularly associated with excessive elevation of Nt-proANP in plasma. Our findings suggest that the influence of heart failure on levels of this peptide in children greatly exceeds the influence of renal dysfunction.