Exercise-induced hemostatic activation in patients with dilated cardiomyopathy in sinus rhythm.

Abnormalities of baseline hemostatic variables have been related to a hypercoagulable state in patients with chronic heart failure (CHF). Given that physical exercise leads to an activation of coagulation physiologically, this study addressed the question of whether the exercise-induced hemostatic activation is enhanced in patients with CHF. Ten patients with dilated cardiomyopathy (ejection fraction < 40%) and 10 healthy individuals (matched for sex, age and body mass index) were subjected to a maximal exercise test on a bicycle ergometer. Healthy subjects performed a second exercise test at a submaximal intensity level, in which oxygen consumption (VO2) was adjusted to the peak oxygen consumption (VO2peak) of the corresponding patient. Exercise testing had only marginal effects on markers of thrombin formation in patients and healthy individuals alike. In patients with CHF, exercise-induced changes in fibrinopeptide A, an index of fibrin formation, paralleled those observed in controls after submaximal exercise whereas most pronounced changes occurred in healthy subjects after maximal exercise. Plasmin-antiplasmin complexes increased almost three-fold with maximal exercise in both groups, thus indicating a marked formation of plasmin. Maximal physical exercise does not induce an exaggerated formation of thrombin and fibrin in CHF patients. The fibrinolytic response to exercise in terms of plasmin formation is not compromised in patients with dilated cardiomyopathy.     

Prognostic value of mechanical efficiency in ambulatory patients with idiopathic dilated cardiomyopathy in sinus rhythm

OBJECTIVES: The purpose of this study was to determine, by analyzing the pressure-volume relationship, the prognostic value of parameters related to myocardial energetics for predicting mortality in patients with dilated cardiomyopathy (DCM) in sinus rhythm. BACKGROUND: The relationship between the myocardial energetics and the prognosis of patients with DCM in sinus rhythm remains unclear. METHODS: We followed 114 ambulatory patients with nonischemic DCM in sinus rhythm for a mean period of 5.8 +/- 3.9 years. Over 70% of our patients were in New York Heart Association functional class I and class II. Pressure-volume data were obtained by the conductance method, and myocardial oxygen consumption per beat (VO(2)) measurements were obtained. RESULTS: The 3-, 5-, and 10-year cumulative survival rates were 88.6%, 80.0%, and 73.9%, respectively. Of the 114 patients, 47 were selected randomly to assess their myocardial energetics. By univariate analysis, the mechanical efficiency (ME, external work/VO(2)), left ventricular (LV) ejection fraction and the LV end-diastolic pressure were statistically associated with cardiac death. The ME was the strongest predictor of survival in a Cox proportional-hazards analysis (p = 0.011). The best cutoff point of ME identified by the receiver-operating curve was 11%. This value had a sensitivity of 100%, a specificity of 87% and an overall predictive accuracy of 88% to distinguish survivors from nonsurvivors. CONCLUSIONS: This study clearly demonstrates that ME is a powerful clinical predictor for cardiac death in patients with mild to moderate heart failure and with sinus rhythm. Whether these conclusions apply to patients with more severe heart failure requires further investigations.     

扩张型心肌病患者肠系膜上动脉血栓栓塞溶栓成功一例

患者女性,52岁,主因"劳力性胸闷、气促10年,心悸10 d"入院.有高血压病史20年,最高达160/80 mm Hg(1 mm Hg=0.133 kPa),间断服用降压药,血压控制不稳定.10年前一般活动时出现胸闷、气促,无胸痛、咳喘,4年前体力活动明显下降,于外院作选择性冠状动脉造影及左心室造影显示左右冠状动脉均未见狭窄,左心室壁收缩活动弥漫性减低,明确诊断为扩张型心肌病.     

Left ventricular thrombosis is associated with increased mean platelet volume in patients with dilated cardiomyopathy and sinus rhythm

OBJECTIVE: Dilated cardiomyopathy has been associated with left ventricular thrombosis, which leads to substantial morbidity and mortality as a site for peripheral emboli. There are some studies on patients with dilated cardiomyopathy showing altered haemostasis and platelet behaviour despite sinus rhythm. Mean platelet volume, which is the most accurate and simple estimate of platelet reactivity, may be associated with the development of left ventricular thrombosis. METHODS AND RESULTS: We prospectively enrolled 48 consecutive patients with dilated cardiomyopathy and sinus rhythm with left ventricular thrombosis and compared them with an age-sex-matched control group having dilated cardiomyopathy without left ventricular thrombosis. We found that in patients with left ventricular thrombosis mean platelet volume is significantly higher than those without (9.5 +/- 0.8 vs. 8.7 +/- 0.6, p < 0.001). CONCLUSIONS: Mean platelet volume is increased in patients with dilated cardiomyopathy and sinus rhythm having left ventricular thrombosis. This might be reflecting a causal relationship, which in turn requires further study to establish the role of antiplatelet agents both in prevention and in treatment.     

Prognostic value of pacing-induced mechanical alternans in patients with mild-to-moderate idiopathic dilated cardiomyopathy in sinus rhythm.

OBJECTIVES: The relation between the occurrence of pacing-induced mechanical alternans and prognosis in patients with mild-to-moderate idiopathic dilated cardiomyopathy (IDCM) in sinus rhythm was investigated prospectively. The myocardial expression of genes for Ca2+-handling proteins in such patients was also examined. BACKGROUND: Mechanical alternans occurs in some patients with severe heart failure, but the relation between the occurrence of mechanical alternans and prognosis in patients with IDCM has remained unknown. METHODS: Left ventricular (LV) pressure was measured during atrial pacing, and LV endomyocardial biopsy specimens were collected in 36 IDCM patients and 8 controls. Idiopathic dilated cardiomyopathy patients were divided into two groups consisting of 22 individuals who did not develop mechanical alternans at heart rates up to 140 beats/min (group A) and of 14 individuals who did (group B). The patients were followed up for a mean of 3.7 years. RESULTS: There was no significant difference in LV ejection fraction or the plasma concentration of brain natriuretic peptide between groups A and B. The myocardial abundance of ryanodine receptor 2 messenger ribonucleic acid (mRNA) was significantly lower in groups A and B than in controls, whereas that of sarcoplasmic reticulum Ca2+-ATPase mRNA was significantly lower in group B than in group A or controls. Stepwise multivariate analysis identified pacing-induced mechanical alternans as the strongest predictor of cardiac events. Event-free survival in group A was significantly greater than that in group B. CONCLUSIONS: The occurrence of pacing-induced mechanical alternans is a potentially useful indicator of poor prognosis in patients with mild-to-moderate IDCM in sinus rhythm.     

N-terminal pro brain natriuretic peptide to predict prognosis in dilated cardiomyopathy with sinus rhythm

AIMS: To assess the value of plasma NT proBNP levels for predicting adverse outcomes in patients with dilated cardiomyopathy (DCM). METHODS: Seventy-eight patients with DCM (EF <40%) with sinus rhythm were enrolled. All patients had undergone echocardiographic examination, coronary angiography, and cardiac catheterisation. Blood samples for plasma NT proBNP levels were taken at rest following echocardiographic examination. Patients were followed up for 660+/-270 days for clinical endpoints defined as; death from worsening heart failure, sudden cardiac death and heart transplantation (Tx). RESULTS: Clinical end points were observed in 19 patients (5 Tx, 4 sudden cardiac death, 10 death from worsening heart failure). Variables associated with an increased hazard of clinical endpoints in univariate analysis were log NT proBNP, age, NYHA functional class, left ventricle ejection fraction, mitral valve effective regurgitation orifice area, and E wave deceleration time. The plasma level of NT proBNP (Hazard ratio=2.5 [95% CI: 1.3-4.7], p=0.0024) and age (hazard ratio=0.94 [95% CI: 0.90-0.98], p=0.0005) were the independent variables associated with an increased risk of clinical endpoints. NT proBNP plasma level >4500 pg/ml detected patients with clinical endpoints with a sensitivity, and specificity of 72%, 80%, respectively. The event free survival was found to be significantly lower in patients with NT proBNP levels >4500 pg/ml. CONCLUSION: NT proBNP seems to be a strong predictor of adverse outcomes in patients with DCM with sinus rhythm and may be used as a reliable biological marker in risk stratification.     

Programmed ventricular stimulation in patients with idiopathic dilated cardiomyopathy and syncope receiving implantable cardioverter-defibrillators: a case series and a systematic review of the literature

BACKGROUND: The role of programmed ventricular stimulation (PVS) in patients with idiopathic dilated cardiomyopathy (DCM) and syncope receiving implantable cardioverter-defibrillators (ICD) remains controversial. METHODS AND RESULTS: Between 1994 and July 2002, 20 patients with DCM and syncope underwent PVS and ICD implantation at the Onassis Cardiac Surgery Center or the Alexandra General Hospital. At PVS 10 patients had inducible sustained monomorphic ventricular tachycardia (SMVT), 3 patients had inducible sustained polymorphic ventricular tachycardia or ventricular fibrillation, and 7 patients had no inducible arrhythmia. The latter 7 patients received an ICD because of clinical occurrence of ventricular tachycardia (n=5) or fibrillation (n=2). Mean age was 55+/-14 years; 80% were men. During a mean follow-up of 2.8+/-2.3 years, 12 of the 20 patients received an appropriate shock. The incidence of appropriate shocks at 1 and 3 years was 69% and 84% in the inducible SMVT group, and 56% and 67% in the group without inducible SMVT (p=0.93, log rank test). Overall survival was similar in both groups (p=0.53). In a systematic review of the published literature 18 of 75 (24%) patients with DCM, syncope and a negative PVS had an appropriate ICD shock after a mean follow-up of 27 months. CONCLUSION: PVS has a limited role in risk stratification of patients with DCM and syncope.     

Beta blocking agents in the treatment of dilated cardiomyopathy: review of the literature and clinical experience with 67 patients]

BACKGROUND. Several reports suggest that chronic beta blockade, most often with the beta 1 selective agent metoprolol, may improve hemodynamic and clinical function in patients with idiopathic dilated cardiomyopathy. However, controlled trials are limited and some studies have not shown beneficial effects in short term trials. Mechanisms of effectiveness are still debated and probably concern the capacity to avoid toxic myocardial damage by catecholamines, to induce receptor up-regulation, to contribute to the control of arrhythmias, to improve diastolic relaxation and other mechanisms. METHODS. After a revision of the literature, a preliminary clinical experience with metoprolol in dilated cardiomyopathy diagnosed according to the WHO definition is reported. Sixty-seven patients symptomatic for congestive heart failure or with complex ventricular arrhythmias associated with severe left ventricular dysfunction were submitted to test dose with metoprolol 5 mg bid for 2-7 days. All patients were completely studied, including coronary angiography and endomyocardial biopsy to exclude ischemic heart disease and active myocarditis. Four pts (6%) did not tolerate the first test dosage of metoprolol and twenty-two patients were excluded from analysis because of inadequate follow-up or because they were enrolled in an international trial. Forty-one patients underwent long-term treatment with metoprolol at a final mean dosage of 150 mg a day (range 50-200 mg) and are presently analyzed. The dosage was gradually increased during the first seven weeks. RESULTS. After 6 +/- 2 months and 12 +/- 2 months, 34 patients were stable or ameliorated (Group 1) and experienced an overall significant improvement of functional class (all pts in class I-II NYHA), of left and right ventricular ejection fraction (from 28 +/- 8.8% to 35.8 +/- 13.7% to 33.2 +/- 12.3% and from 38.6 +/- 11.8% to 42.4 +/- 5.8% to 45.2 +/- 12.2% respectively), of clinical signs of congestive heart failure, of cardiothoracic index, of left ventricular diameters and of arrhythmic pattern. Furthermore, the rate of ventricular couplets > 20/24h and of non-sustained ventricular tachycardia changed respectively from 46% and 54% to 4% and 21% at 12 +/- 2 months. None in Group 1 died nor is any waiting for heart transplantation. Eleven patients (Group 2) did not tolerate the drug acutely (4 pts) or deteriorated during the first 6 +/- 2 months (7 pts) of the treatment. In this group a worsening or an insignificant variation of all clinical and instrumental parameters was observed. During follow-up four patients of this group underwent heart transplantation (one died shortly after the operation because of infective complications), one died while waiting, two are currently waiting for heart transplantation, and three are still in heart failure (class III NYHA). No cases of sudden death occurred in any group of patients (15 pts with follow-up > 12 mo). CONCLUSIONS. Our uncontrolled study seems to confirm the beneficial effect of betablockers in a subgroup of patients with idiopathic dilated cardiomyopathy. The characterization of responders to this therapy is still undefined and will constitute the aim of future analyses.     

Assessment of heart rhythm in patients with dilated cardiomyopathy based on daily ECG monitoring data

The quantitative and qualitative characteristics of arrhythmias were examined, using continuous 24-hour ECG monitoring, in 25 patients with dilatation cardiomyopathy. Supraventricular extrasystole was found in 100% of patients with the sinus rhythm, and ventricular extrasystoles, in 94% of patients, being most commonly associated with poor prognosis (polytopic extrasystoles in 84%, paired extrasystoles in 60%, and paroxysmal ventricular tachycardia in 40%). Disorders of atrio-ventricular conductivity were recorded in 47.6% of patients with the sinus rhythm, 23.8% of those showing a permanent 1st-degree block, and the rest, a transient block of the 1st--3d degree. It was demonstrated that arrhythmias could serve as a permanent sign of dilatation cardiomyopathy, being most commonly of a complex nature and associated with poor prognosis.     

Familial dilated cardiomyopathy in patients transplanted for idiopathic dilated cardiomyopathy

OBJECTIVE: To evaluate the prevalence, clinical features, and pattern of inheritance of familial dilated cardiomyopathy (DCM) in heart transplant patients. PATIENTS AND METHOD: Patients with idiopathic DCM who had undergone heart transplantation were invited to participate. Patients with alcohol abuse were excluded. A clinical evaluation, 12-lead ECG, echocardiogram, blood tests, and DNA extraction were performed in patients and relatives. Familial DCM was defined as the presence of at least one relative with idiopathic DCM. Possible familial DCM was considered when at least one relative had left ventricular enlargement (LVE) (> 112% predicted LVEDD). RESULTS: One hundred and ninety-nine relatives of 43 families were studied. DCM was familial in 11 probands (25.6%) and possibly familial in 11 (25.6%). Fifteen relatives had DCM (7.5%), 26 (13.1%) LVE, and 5 (2.5%) hypertrophic cardiomyopathy. The pattern of inheritance was autosomal dominant in most families. Five probands (3 with familial DCM) had antecedents of consanguinity and possible recessive inheritance. Six probands (14%, 1 with familial DCM) had relatives with conduction system defects. Creatine kinase was moderately increased in 9 relatives (4.5%), 3 of them with LVE. Fifteen patients had at least moderate alcohol intake. Three of them had familial DCM (relatives without alcohol abuse) and 6 had possible familial DCM. CONCLUSIONS: The prevalence of familial DCM is high in patients who undergo heart transplant. Left ventricular enlargement, conduction system abnormalities, and elevated creatine kinase may be early markers of familial disease. Hypertrophic cardiomyopathy is present in some relatives of patients with idiopathic DCM. Familial DCM is present in patients with a previous diagnosis of alcoholic DCM.     

Lyme carditis--rare cause of dilated cardiomyopathy and rhythm disturbances

Case report of young woman presents involvement of dilated cardiomyopathy and rhythm disturbances in 18 months after infection of tick, with direct assessment of spirochetes in myocardial tissue. Cardial decompensation occured after asthma exacerbation, complicated by bronchopneumonia. Rhythm disturbances and heart failure gradually subside after parenteral antibiotic treatment and peroral treatment of heart failure. Nevertheless there is a long-lasting persistence of dilated cardiomyopathy with significant systolic dysfunction, which is supposedly last consequence of Borrelia infection. Resynchronic therapy combinated with cardioverter-defibrilator primary considering was postponed for improvement clinical condition and myocardial electric stability. There is demonstrating complicated serologic diagnostics of Lyme disease in discussion. Lyme carditis would be part of differential diagnosis in rhythm disturbances and cardiomyopathy of unknown etiology, including serious or fatal events.     

Significance of accelerated idioventricular rhythm in idiopathic dilated cardiomyopathy

Holter monitoring was performed in 202 patients with idiopathic dilated cardiomyopathy, which revealed accelerated idioventricular rhythm in 16 patients (8%) and nonsustained ventricular tachycardia in 70 patients (35%). During 32 +/- 15-month prospective follow-up, no significant difference was observed for major arrhythmic events and transplant-free survival between patients with and without accelerated idioventricular rhythm, whereas patients with nonsustained ventricular tachycardia had a significantly higher incidence of major arrhythmic events and a lower transplant-free survival rate.     

Relevance of cardiac parvovirus B19 in myocarditis and dilated cardiomyopathy: review of the literature

Over the last decade, parvovirus B19 (B19V) has frequently been linked to the pathogenesis of myocarditis (MC) and its progression towards dilated cardiomyopathy (DCM). The exact role of the presence of B19V and its load remains controversial, as this virus is also found in the heart of healthy subjects. Moreover, the prognostic relevance of B19V prevalence in endomyocardial biopsies still remains unclear. As a result, it is unclear whether the presence of B19V should be treated. This review provides an overview of recent literature investigating the presence of B19V and its pathophysiological relevance in MC and DCM, as well as in normal hearts. In brief, no difference in B19V prevalence is observed between MC/DCM and healthy control hearts. Therefore, the question remains open whether and how cardiac B19V may be of pathogenetic importance. Findings suggest that B19V is aetiologically relevant either in the presence of other cardiotropic viruses, or when B19V load is high and/or actively replicating, which both may maintain myocardial (low‐grade) inflammation. Therefore, future studies should focus on the prognostic relevance of the viral load, replicative status and virus co‐infections. In addition, the immunogenetic background of MC/DCM patients that makes them susceptible to develop heart failure upon presence of B19V should be more thoroughly investigated.     

Empirical anticoagulation for patients in sinus rhythm at high risk of ischaemic stroke:A review of current literature

Ischaemic stroke is one of the commonest causes of morbidity and mortality worldwide and around a fifth of events can be attributed to a cardioembolic source. This is typically due to atrial fibrillation(AF), the most common sustained cardiac arrhythmia. However, AF can, at times, be difficult to detect due to a relative lack of symptoms and the fact that it can be paroxysmal in nature. Studies have shown that diagnosis of AF improves as the length of cardiac monitoring increases. However, prolonged cardiac monitoring is not a costeffective way of diagnosing AF. Therefore, an alternative approach may be to empirically anticoagulate individuals who are at high risk of stroke. This article summarises current evidence surrounding stroke risk prediction, the use of anticoagulation in the secondary prevention of stroke and its use in the primary prevention of stroke in high risk groups with the aim of determining whether empirical anticoagulation is a safe and effective strategy.