Sudden cardiac death in patients with nonischemic cardiomyopathy

Sudden cardiac death (SCD) is an important cause of mortality worldwide. Although SCD is most often associated with coronary heart disease, the risk of SCD in patients without ischemic heart disease is well-established. Nonischemic cardiomyopathies, including idiopathic dilated cardiomyopathy, hypertrophic cardiomyopathy and arrhythmogenic right ventricular cardiomyopathy represent three unique disease entities that have been shown to be highly associated with SCD and ventricular arrhythmias. A variety of risk stratification tools have been investigated, although the optimal strategy remains unknown. Identification of the arrhythmogenic substrate and treatment of ventricular arrhythmias in these subgroups can be challenging. Herein, we aim to discuss the current understanding of the anatomic and electrophysiologic substrate underlying ventricular arrhythmias and highlight features that may be associated with a higher risk of SCD in these 3 conditions.     

Systematic review of pregnancy in women with inherited cardiomyopathies

Pregnancy exposes women with inherited cardiomyopathies to increased risk for heart failure and arrhythmias. In this paper, we review the clinical course and management of pregnant women with the following inherited cardiomyopathies: hypertrophic cardiomyopathy, dilated cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, left ventricular non-compaction cardiomyopathy, and restrictive cardiomyopathy. We also discuss peripartum cardiomyopathy. Pregnancy is generally well tolerated in asymptomatic patients with inherited cardiomyopathies. However, worsening of the clinical condition can occur during pregnancy, despite intensive medical treatment. If prior cardiac events, poor functional class (New York Heart Association class III or IV), or advanced left ventricular systolic dysfunction are present, the risk of maternal cardiac complications during pregnancy are markedly increased. The postpartum condition is generally no worse than the antepartum condition, but no long-term follow-up studies have been reported. Preconception evaluation and counselling are important aspects of managing women with inherited cardiomyopathies. Genetic counselling and DNA testing should be offered to all women following the diagnosis of an inherited cardiomyopathy.     

Pregnancy in patients with pre-existing cardiomyopathies

To varying extents, women with pre-existing cardiomyopathies have a limited cardiovascular reserve. The hemodynamic challenges of pregnancy, labor, and delivery pose unique risks to this group of patients, which can result in clinical decompensation with overt heart failure, arrhythmias, and rarely, maternal death. A multidisciplinary team approach and a controlled delivery are crucial to adequate management of patients with underlying heart disease. Pre-conception planning and risk assessment are essential, and proper counseling should be offered to expectant mothers with regard to both the risks that pregnancy poses and the implications for future offspring. In this article, we will review the hemodynamic stressors that pregnancy places upon women with pre-existing cardiomyopathies and risk assessment and discuss what evidence exists with regard to the management of 2 forms of cardiomyopathy during pregnancy, labor, and delivery: dilated and hypertrophic cardiomyopathy.     

Role of hepatitis C virus in myocarditis and cardiomyopathies

Recent nationwide clinico-epidemiological surveys in Japan showed that the occurrence of cardiomyop-athies was most frequently seen in the age of sixties,and that cardiomyopathies are important causes of heart failure inthe elderly.Viral infection was conventionally considered to cause myocarditis,which resulted in the development ofdilated cardiomyopathy.Recent studies suggest that hepatitis C virus(HCV)is involved in the development of dilatedcardiomyopathy,hypertrophic cardiomyopathy and arrhythmogenic right ventricular cardiomyopathy in addition to myo-carditis.Furthermore,left ventricular aneurysm represents the same morbid state not only after myocardial infarctionbut also after myocarditis.There were wide variations in the frequency of detection of HCV genomes in cardiomyopathyin different regions and in different populations.Major histocompatibility complex class Ⅱ genes may play a role in thesusceptibility to HCV infection,and may influence the development of different phenotypes of cardiomyopathy.If infact the myocardial damage is caused by HCV,it might be expected that interferon(IFN)administration would beuseful for its treatment.Hepatitis patients receiving IFN treatment for hepatitis were screened by thallium myocardialscintigraphy,and an abnormality was discovered in half of the patients.Treatment with IFN resulted in a disappear-ance of the image abnormality.It has thus been suggested that mild myocarditis and myocardial damage may be curedwith IFN.We have recently found that high concentrations of circulating cardiac troponin T are a specific marker ofcardiac involvement in HCV infection.By measuring cardiac troponin T in patients with HCV infection,the preva-lence of cardiac involvement in HCV infection will be clarified.We are proposing a collaborative work on a globalnetwork on myocarditis/cardiomyopathies due to HCV infection.(J Geriatr Cardiol 2004;1(2):83-89.)     

Comparison of long-term outcome of alcoholic and idiopathic dilated cardiomyopathy.

AIMS: The outcome of alcoholic cardiomyopathy is thought to be better than idiopathic dilated cardiomyopathy if patients abstain from alcohol. The aim of this study was to compare the long-term clinical outcome of alcoholic and idiopathic dilated cardiomyopathy. METHODS AND RESULTS: Of 134 patients with dilated cardiomyopathy and normal coronary angiography, 50 had alcoholic cardiomyopathy; they were compared serially to 84 patients with idiopathic dilated cardiomyopathy. Left ventricular end-diastolic diameter, left ventricular ejection fraction and cardiac index, severity of ventricular arrhythmias, measurement of heart rate variability and results of signal-averaged ECG were similar in both groups. Although alcohol withdrawal was strongly recommended but observed in only 70% of patients with alcoholic cardiomyopathy, both groups had similar outcome in terms of cardiac death after follow-up treatment of 47+/-40 months. Multivariate analysis in the entire cohort demonstrated that increased pulmonary capillary wedge pressure (P=0. 003), alcoholism and lack of abstinence during follow-up (P=0.006) and decreased standard deviation of all normal-to-normal RR intervals (P=0.02) were independent predictors of cardiac death. CONCLUSION: In contrast with previous studies, patients with alcoholic cardiomyopathy did not have a better outcome than patients with idiopathic dilated cardiomyopathy. Alcoholism without abstinence was a strong predictor of cardiac death. This suggests that a more aggressive approach to alcohol cessation is needed in these patients.     

Cardiac features of Emery-Dreifuss muscular dystrophy caused by lamin A/C gene mutations.

AIMS: Retrospective studies have identified a mutation in the lamin A/C (LMNA) gene in patients selected on the basis of a phenotype characterized by dilated cardiomyopathy, atrioventricular conduction disturbances and sudden death. However, the features of cardiac abnormalities in patients with an initial diagnosis of Emery-Dreifuss muscular dystrophy (EDMD) are poorly known. Aim of the present study was to investigate the spectrum of cardiac disease in patients with an initial diagnosis of EDMD caused by a mutation in the LMNA gene. METHODS AND RESULTS: Ten consecutive patients with EDMD and a LMNA gene mutation were evaluated with structured medical interview, physical examination, ECG, echocardiogram and 24-h Holter monitoring. Electrophysiological testing and cardiac catheterization were performed if a class 1 or 2 American Heart Association guidelines indication was present. Cardiac disease was found in eight of 10 patients and consisted in the variable combination of supraventricular arrhythmias, disorders of atrioventricular conduction, ventricular arrhythmias, dilated cardiomyopathy, non-dilated cardiomyopathy, restrictive cardiomyopathy and sudden death despite pacemaker implant. CONCLUSIONS: Cardiac disease is common in patients with an initial diagnosis of EDMD caused by a mutation in the LMNA gene and consists of arrhythmias, disorders of atrioventricular conduction, cardiomyopathies and sudden death despite pacemaker implant.     

Electrophysiological Effects of Carvedilol Administration in Patients with Dilated Cardiomyopathy

PURPOSE: Several studies suggest the clinical efficacy of carvedilol in reducing atrial and ventricular arrhythmias in patients with left ventricular dysfunction (LVD) due to congestive heart failure (CHF) or following myocardial infarction. However, the mechanisms supporting its antiarrhythmic efficacy have been derived from experimental studies. In this prospective, placebo-controlled trial we examined the electrophysiological effects of a high oral dose of carvedilol in patients with CHF and LVD due to non-ischemic dilated cardiomyopathy. METHODS: Thirty-one patients with stable CHF underwent electrophysiological study and were randomly assigned to treatment with carvedilol or placebo. After 2 months of treatment the study was repeated. RESULTS: Carvedilol prolonged almost all conduction times. In the same group atrial and ventricular effective refractory periods were significantly prolonged, while the parameters of repolarization remained virtually unchanged. The prolongation of refractoriness was most pronounced in the atrium. The change in ventricular refractoriness was correlated with ejection fraction (r = 0.94, p < 0.01) suggesting that patients with more preserved left ventricular function responded to treatment with greater prolongation. CONCLUSION: Even after a short period of administration carvedilol has marked and diffused electrophysiological effects that would be beneficial for patients with CHF and may contribute to the positive outcome of clinical trials.     

Double missense mutations in cardiac myosin‐binding protein C and myopalladin genes: A case report with diffuse coronary disease,complete atrioventricular block,and progression to dilated cardiomyopathy

Cardiomyopathies caused by double gene mutations are rare but conferred a remarkably increased risk of end‐stage progression, arrhythmias, and poor outcome. Compound genetic mutations leading to complex phenotype in the setting of cardiomyopathies represent an important challenge in clinical practice, and genetic tests allow risk stratification and personalized clinical management of patients. We report a case of a 50‐year‐old woman with congestive heart failure characterized by dilated cardiomyopathy, diffuse coronary disease, complete atrioventricular block, and missense mutations in cardiac myosin‐binding protein C (MYBPC3) and myopalladin (MYPN). We discuss the plausible role of genetic profile in phenotype determination.     

BMIPP compared with thallium redistribution

I-123 labeled methyl-branched fatty acid, BMIPP, has been used mainly in Europe and Japan for the evaluation of various cardiac diseases. BMIPP uptake abnormality is usually more prominent than perfusion, representing discordant BMIPP uptake less than thallium. This finding is observed in various cardiac disease conditions such as acute myocardial infarction, stable and unstable angina, hypertrophic and dilated cardiomyopathies. Many BMIPP studies combined stress thallium imaging in patients with coronary artery disease and hypertrophic cardiomyopathy demonstrated that such discordant BMIPP uptake less than thallium is related to stress-induced ischemia as evidenced by reversible thallium defect after exercise. BMIPP imaging is able to detect metabolic alteration in the heart which is not available by perfusion imaging alone.     

Regression of dilated cardiomyopathy in a chronic alcoholic patient after abstinence from alcohol

The authors report the case of a 28 year old alcoholic who was admitted to hospital for cardiac failure in 1982 due to a dilated cardiomyopathy. The clinical and paraclinical signs disappeared after cessation of alcohol intake. Three years after abstaining from alcohol, the electrocardiogram, echocardiogram and isotopic ventriculography are normal. This case illustrates the necessity of absolute cessation of alcohol intake in patients with dilated cardiomyopathies.     

Arrhythmic manifestations in patients with congenital left ventricular aneurysms and diverticula

Congenital left ventricular aneurysms and diverticula (LVA/Ds) are rare cardiac malformations that can be detected using echocardiography or other imaging techniques. Some of these patients present with ventricular arrhythmias. This study investigated clinical characteristics of patients with congenital LVA/D presenting with arrhythmic manifestations. Over the previous 20 years 250 patients were diagnosed to have congenital LVA/D at our institution. Diagnosis was made using echocardiography after exclusion of coronary artery disease, local cardiac inflammatory processes, traumatic causes, or cardiomyopathies. At initial presentation 32 of the 250 patients (13%, average age 45 years, range 25 to 65, 21 men and 11 women) exhibited arrhythmias. At least 2 LVA/Ds were present in 6 of these patients. LVA/Ds were localized at the posterobasal, apical, anteroseptal, and anterolateral walls in 12, 11, 4, and 5 patients, respectively. The most common complaints at presentation were syncope or presyncope in 18 patients and palpitations in 11 patients. One patient had survived sudden cardiac death. Long-term electrocardiographic recordings showed ventricular tachycardia (VT) or ventricular fibrillation in 17 patients (53%). Twelve patients underwent electrophysiologic testing. Nine patients had inducible ventricular tachyarrhythmia, whereas induced tachycardia was similar to that during spontaneous arrhythmia in 7 patients. In conclusion, patients with congenital LVA/Ds who present with arrhythmic manifestations commonly have VT. Electrophysiologic testing can reproduce clinical VT in most of these patients.     

Sudden death related cardiomyopathies – Arrhythmogenic right ventricular cardiomyopathy,arrhythmogenic cardiomyopathy,and exercise-induced cardiomyopathy

Sudden cardiac death (SCD) is a devastating possible outcome of all cardiomyopathies. The risk of SCD is increased in patients with structural heart disease and continues to increase as ventricular dysfunction worsens. There is, however, a subset of cardiomyopathy, so-called “arrhythmogenic cardiomyopathy” (ACM), that carries an inherent propensity for arrhythmia in all stages of the disease, even preceding ventricular dysfunction. The aim of this review is to identify cardiomyopathies, other than ischemic and dilated cardiomyopathies, that are associated with ventricular arrhythmias (VAs) and SCD. We discuss prevalence, diagnosis, natural history and management of arrhythmogenic right ventricular dysplasia/cardiomyopathy, ACM, and exercise-induced cardiomyopathy, with emphasis on the morbidity and mortality of VAs associated with these cardiomyopathies and how they can be mitigated through lifestyle modification, medical management, and implantation of cardioverter defibrillators.     

Management of patients with dilated cardiomyopathies and ventricular arrhythmias

Abstracts

Management of patients with dilated cardiomyopathies and ventricular arrhythmias     

Experience with the use of an implantable automatic cardioverter defibrillator

An automatic implantable cardioverter-defibrillator with pacemaker was implanted in Cuba, in ten patients with malignant ventricular arrhythmias, sudden cardiac collapse, and ventricular tachycardia with syncope, after a previous electrophysiological study for analysis of the arrhythmia and pharmacological evaluation. The patients were 9 males, ranging in age from 23 a 70 years, with a mean of 48 years, and an ejection fraction of 32% (18-62%). The etiologies were: an old myocardial infarction (7 cases) and dilated cardiomyopathy (3 cases). During the follow-up, mean from 2 to 25 months, four patients received effective shocks for rapid palpitations and presyncope. Two patients died, one due to incessant ventricular tachycardia and one of a cause unrelated to device. We concluded that the GUARDIAN 4201 and 4202 device are useful to prevent sudden cardiac death in high risk patients who experienced a life threatening arrhythmia.     

The Clinical Significance of Nonsustained Ventricular Tachycardia

Nonsustained Ventricular Tachycardia. Nonsustained ventricular tachycardia (NSVT) is an arrhythmia not often associated with symptoms; however, its occurrence in patients with structural heart disease is a prognostic indicator of an increased risk of mortality and sudden death. The management of asymptomatic patients with NSVT should first attempt to identify which patients are at highest risk for cardiac arrest, and second, devise a treatment that can reduce the incidence and/or mortality of cardiac arrest in this group. In patients with chronic coronary artery disease (CAD) and NSVT, programmed electrical stimulation identifies both a low and high risk group with respect to occurrence of ventricular arrhythmias. The negative predictive value of programmed electrical stimulation in patients with CAD and NSVT has been well established; however, uncertainty remains as to the optimal therapy for CAD patients with inducible ventricular arrhythmias. A number of reports suggest that patients whose inducible ventricular arrhythmias are rendered noninducible with antiarrhythmic drugs have a much lower risk of sudden death. It is yet to be resolved whether arrhythmias rendered noninducible identify a subgroup at low risk for cardiac arrest, independent of treatment. There is some evidence to suggest that the frequency of NSVT in patients with nonischemic dilated cardiomyopathy identifies a group at higher risk of sudden death. Programmed electrical stimulation adds little in helping to identify which of these patients are most likely to have cardiac arrest. The presence of NSVT in asymptomatic patients with hypertrophic cardiomyopathy may identify a group at higher risk for cardiac arrest. Further clinical studies are needed to define the best management strategy for NSVT in different types of structural heart disease.     

卡维地洛治疗扩张型心肌病复杂型室性心律失常的疗效评价

目的 :探讨卡维地洛治疗扩张型心肌病复杂型非持续性室性心律失常的临床疗效。方法 :将 10 4例缺血性或特发性扩张型心肌病复杂型心律失常患者随机分成两组 :卡维地洛组 5 4例 ,对照组 5 0例 ,两组均常规强心、利尿及血管紧张素转换酶抑制剂类药物治疗 ,仅卡维地洛组加用卡维地洛口服治疗 ;疗程 6月。采用 2 4 h动态心电图和多普勒超声心动图 ,观测治疗前后的 HR、室性早搏 （PVC）、非持续性室性心动过速 （NSVT）、左心室射血分数（L VEF）。结果 :经卡维地洛治疗 1月后 ,卡维地洛组较对照组抗心律失常作用增加明显 ,有显著性差异 （P<0 .0 5 ） ;3月后 ,卡维地洛组较对照组 L VEF明显增加 （P<0 .0 5 ） ,抗心律失常作用在卡维地洛组进一步增加 ,而 HR、血压无明显变化 （P>0 .0 5 ）。结论 :在传统抗心衰药物治疗的基础上长期加用卡维地洛 ,对治疗扩张型心肌病复杂型室性心律失常具有明显疗效     

Severe dilated cardiomyopathy and quadriceps myopathy due to lamin A/C gene mutation: a phenotypic study

This study reports a family affected by a new phenotype associated with dilated cardiomyopathy and quadriceps myopathy. METHODS: 29 family members underwent a physical and neurological examination, including an electromyogram and biopsy of muscle abnormalities. A cardiac examination was performed in all subjects. RESULTS: The family pedigree (n=72) demonstrated that transmission was autosomal dominant. Eleven subjects had cardiac involvement, only four had quadriceps muscle involvement. Cardiac impairment preceded neurological involvement. The mean age for neurological involvement was 44+/-0.8 years (range 43-45) and cardiac involvement was 37+/-7.9 years (range: 24-45). Cardiac involvement consisted of: hypokinetic dilated cardiomyopathy (64%); atrial fibrillation (100%); ventricular arrhythmias (64%); impaired conduction with bundle branch or complete atrio ventricular block (73%). Four patients required pacemakers and anti arrhythmic therapies. Four patients died: two of refractory heart failure and two of sudden death; two patients were resuscitated following cardiac arrest. Three patients required a prophylactic implantable cardiac defibrillator (ICD). Muscle morphological abnormalities were characterized by a variable number of fibers with rimmed vacuoles. The quadriceps deteriorated progressively without impairment of other muscles. Genotypic study showed a lamin A/C gene mutation. CONCLUSIONS: This family was affected by a new phenotype composed of an autosomal dominant severe dilated cardiomyopathy with conduction defects or arrhythmias and quadriceps myopathy. Cardiac abnormalities preceded neuromuscular disorders and defined the prognosis of this disease.     

Kommentar zu den „ACC/AHA/ESC 2006 guidelines for management of patients with ventricular arrhythmias and the prevention of sudden cardiac death – executive summary“

The purpose of this document is to translate and to comment on the previously published“ACC/AHA/ESC 2006 guidelines for management of patients with ventricular arrhythmias and the prevention of sudden cardiac death”. The aim is to update the recommendations for clinical practice in Germany. We address the diagnostic procedures (e.g. ECG, imaging, electrophysiological studies etc.) and therapeutic options (e.g. medical treatment, catheter ablation, implantable cardioverter defibrillator – ICD etc.). Special emphasis was put on management of acute ventricular arrhythmias and on the different treatment modalities for various conditions (e.g. ischemic cardiomyopathy, valvular heart disease, congenital heart disease, non-ischemic cardiomyopathies, congestive heart failure, genetic arrhythmia syndromes etc.). Comments are given in each chapter, including the ongoing debate about ICD indications in primary prophylaxis.     

Chagas heart disease: report on recent developments

Chagas disease, caused by the parasite Trypanosoma cruzi, is an important cause of cardiac disease in endemic areas of Latin America. It is now being diagnosed in nonendemic areas because of immigration. Typical cardiac manifestations of Chagas disease include dilated cardiomyopathy, congestive heart failure, arrhythmias, cardioembolism, and stroke. Clinical and laboratory-based research to define the pathology resulting from T. cruzi infection has shed light on many of the cellular and molecular mechanisms leading to these manifestations. Antiparasitic treatment may not be appropriate for patients with advanced cardiac disease. Clinical management of Chagas heart disease is similar to that used for cardiomyopathies caused by other processes. Cardiac transplantation has been successfully performed in a small number of patients with Chagas heart disease.     

Outcome of Right Ventricular Bifocal Pacing in Patients with Permanent Atrial Fibrillation and Severe Dilated Cardiomiopathy Due to Chagas Disease: Three Years of Follow-up

OBJECTIVES OF STUDY: Several studies have shown that heart failure may benefit from cardiac resynchronization therapy (CRT). Studies have demonstrated a beneficial effect of right ventricular (RV) bifocal pacing, using two leads at different positions, in similar patient populations. The aim was to evaluate this approach in Chagas disease patients who developed both severe dilated cardiomiopathy and chronic atrial fibrillation. METHODS: The study included 30 patients with a mean age of 52 +/- 6 years (16 male), who had atrioventricular block at functional class II or IV (NYHA). Patients underwent endocardial dual-chamber pacemaker implantation with two RV leads-one placed near the RV outflow tract and the other in the apex. Patients were examined by echocardiography, 24-hour Holter, and New York Heart Association (NYHA) class determination before and 3, 6, 12, 18, 24, and 36 months after CRT. RESULTS: Compared to the baseline, the left ventricular ejection fraction increased in the first month of CRT, the left ventricular end diastolic diameter decreased, all patients were downgraded to NYHA class I or II, and the incidence of ventricular arrhythmias decreased. However, these could not be maintained and worsened after 6 months CRT. There was a mortality rate of 43.3% during the first year, and only 23.3% of patients remained alive after 3 years. They underwent an electrophysiological study, which revealed complex arrhythmias justifying implantable cardioverter defibrillator (ICD) in six out of seven patients. CONCLUSION: The favorable effects of RV bifocal pacing could not be maintained beyond the first 6 months, likely due to the ventricular arrhythmias. Therefore, CRT combined with ICD from the outset may be recommended for this patient group.