Left ventricular apical aneurysm in hypertrophic cardiomyopathy as a risk factor for sudden death at any age

In hypertrophic cardiomyopathy (HCM) aging has proved protective against sudden death (SD) risk and aggressive recommendations for prophylactic ICDs are uncommon in patients ≥60 years. Nevertheless, we present a patient with an unexpected but aborted sudden death event at the advanced age of 71 years due to a left ventricular apical aneurysm (LVAA) which has emerged as a novel SD marker. Subsequent reappraisal of the Tufts HCM database, specifically the 118 LVAA patients, showed that 36% of SD events occurred at ≥60 years. Of HCM patients ≥ 60 years, SD was 8‐fold more common with aneurysm than without aneurysms (16% vs 2%; P < 0.001). Risk in HCM with LVAA persists throughout life and senior LVAA patients should also be considered for primary prevention of SD with the ICD.     

Efficacy of implantable cardioverter defibrillator therapy for primary and secondary prevention of sudden cardiac death in hypertrophic cardiomyopathy

Risk stratification and effectiveness of implantable cardioverter-defibrillator (ICD) therapy are unresolved issues in hypertrophic cardiomyopathy (HCM), a cardiac disease that is associated with arrhythmias and sudden death. We assessed ICD therapy in 132 patients with HCM: age at implantation was 34 +/- 17 years, and 44 (33%) patients were aged 相似文献   

Sudden Death Due to Atrial Fibrillation in Hypertrophic Cardiomyopathy:

FAVALE, S., et al .: Sudden Death Due to Atrial Fibrillation in Hypertrophic Cardiomyopathy: A Predictable Event in a Young Patient. This case refers to a 39-year-old woman with hypertrophic cardiomyopathy (HCM) and family history of sudden death (SD). In 1985, high rate atrial stimulation induced VF. In 1996 an ICD was implanted and she remained without arrhythmic events until November 2000 when the device reported one episode of atrial fibrillation degenerating into VF and terminated by the ICD. The VF induction mechanism recorded by the ICD was similar to that observed in 1985. The high incidence of atrial tachyarrhythmias in HCM renders cases like this at higher risk of SD. The predictive role of incremental atrial stimulation merits highlighting in future studies. (PACE 2003; 26[Pt. I]:637–639)     

Preexcitation in Hypertrophic Cardiomyopathy: A Case of a Fasciculoventricular Mahaim Fiber

STELLBRINK, C., et al .: Preexcitation in Hypertrophic Cardiomyopathy: A Case of a Fasciculoventricular Mahaim Fiber . A patient with hypertrophic cardiomyopathy (HCM) who presented with preexcitation pattern on the surface ECG suggestive of the Wolff-Parkinson-White (WPW) syndrome is described. Intracardiac electrophysiological study revealed a fixed anomalous QRS complex and a short fixed His-ventricular interval indicating a fasciculoventricular Mahaim fiber. As this specific form of accessory connection does not cause reentrant tachycardias, no treatment was required. It is important to distinguish this entity from atriofascicular or nodoventricular Mahaim fibers or the WPW syndrome in patients with HCM showing a preexcitation pattern in the surface ECG, as these may cause life-threatening arrhythmias in this patient population.     

Hypertrophic Cardiomyopathy: valuation and Treatment of Patients at High Risk for Sudden Death

Hypertrophic cardiomyopathy (HCM) is a heritable disease characterized by LV hypertrophy with markedly variable clinical, morphological, and genetic manifestations. It is the most common cause of sudden death in otherwise healthy young individuals. HCM patients often have disabling symptoms and are prone to arrhythmias. Frequently, there is associated LV systolic and diastolic dysfunction, LV outflow obstruction, and myocardial ischemia. Over the past decade, progress has been made in identifying patients who are at high risk for sudden death, in elucidating potential mechanisms of sudden death, and in defining therapeutic algorithms that may improve prognosis. It has also been possible to determine the genetic defect in some of the patients and to correlate clinical findings with the molecular defects. An exciting development has been the use of the dual chamber pacemaker as an alternative to cardiac surgery to improve symptoms and relieve LV outflow obstruction.     

Risk stratification for sudden death in arrhythmogenic right ventricular cardiomyopathy

Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC) is an uncommon but increasingly recognized inherited cardiomyopathy that is associated with malignant ventricular arrhythmias and sudden cardiac death, particularly in young individuals. The implantable cardioverter-defibrillator (ICD) is widely regarded as the only treatment modality with evidence to support improved survival in patients with ARVC and secondary prevention indications. In contrast, there is no universally accepted risk stratification scheme to guide ICD therapy for primary prevention against sudden cardiac death. Potential benefits must be weighed against the considerable risks of complications and inappropriate shocks in this young patient population. This article tackles the challenges of risk stratification for sudden cardiac death in ARVC and critically appraises available evidence for various proposed risk factors. The authors’ over-arching objective is to provide the clinician with evidence-based guidance to inform decisions regarding the selection of appropriate candidates with ARVC for ICD therapy.     

The Value of Electrophysiology Study and Prophylactic Implantation of Cardioverter Defibrillator in Patients with Hypertrophic Cardiomyopathy

Fifty-three consecutive patients with hypertrophic cardiomyopathy (HCM) and no history of sudden death underwent electrophysiology (EP) study. Sustained polymorphic ventricular tachycardia (VT) or ventricular fibrillation (VF) was induced in 19 patients (35%). Patients with prior syncope or near syncope had a higher incidence of VT/VF inducibility. An implantable cardioverter defibrillator (ICD) was placed in 14 of the 19 patients. Of the remaining 5 patients with inducible VT/VF, three refused ICD implantation, while two underwent septal myectomy and VT/VF was no longer inducible afier the operation. None of the patients received antiarrhythmic drugs. During a mean follow-up period of 47 ± 31 (2–117) months, no events occurred in the 34 patients with negative EP study. Three events occurred among the 19 patients with inducible VT/VF. One patient died suddenly, one developed wide complex tachycardia which required resuscitation, and one patient received an appropriate ICD shock. In conclusion, sustained polymorphic VT/VF was inducible in about one-third of patients with HCM. Noninducibility of VT/VF appeared to predict a favorable prognosis. Although the overall event rate was low in patients with inducible VT/VF, prophylactic ICD implantation in patients with multiple risk factors may be appropriate.     

Sustained ventricular tachycardia in apical hypertrophic cardiomyopathy, midcavitary obstruction, and apical aneurysm

The prevalence of hypertrophic cardiomyopathy is estimated at 1:500 in the general population. Of these patients, approximately 1% develops midcavitary obstruction and subsequent apical aneurysm. We present a brief review of the literature on apical hypertrophic cardiomyopathy (HCM) using a rare case-based example. The etiology for apical aneurysm development is unclear but is thought to extend from apical fibrosis and necrosis secondary to subendocardial ischemia. The lifetime risk of cardiovascular death in patients with HCM is 2%. However, the risk may be higher in patients with apical aneurysms. Definitive therapy involves implantation of an automatic implantable cardioverter defibrillator, since medical therapy has variable success.     

Risk stratification for ventricular arrhythmias and sudden cardiac death in arrhythmogenic right ventricular cardiomyopathy: an update

ABSTRACT

Introduction: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a genetically determined disease associated with a significant risk of ventricular arrhythmias and sudden cardiac death (SCD). Implantable cardioverter-defibrillators (ICDs) are the only effective preventive measure. Over the past 30 years, much effort has been invested in determining predictors of adverse arrhythmic events in these patients.

Areas covered: This review summarizes available evidence on risk stratification for ARVC, with an emphasis on recent research findings. While efforts are ongoing to define risk predictors, several recent publications have synthetized and built on this knowledge base. A recently published meta-analysis has clarified the strongest predictors of ventricular arrhythmias in ARVC, which vary depending on the population included. Three management guidelines/expert consensus documents have integrated the previously described risk predictors into proposed ICD recommendations. Furthermore, a risk prediction model has allowed the integration of multiple risk factors to provide individualized risk prediction and to inform shared-decision making regarding ICD implantation.

Expert opinion: Over the past few years, knowledge of risk prediction in ARVC has been consolidated and refined. Further improvements may be made by the considering additional predictors such as exercise and by targeting more specific surrogate outcomes for SCD.     

Hypertrophic cardiomyopathy in Noonan Syndrome closely mimics familial hypertrophic cardiomyopathy due to sarcomeric mutations

A 27 year old female with Noonan syndrome and hypertrophic cardiomyopathy underwent cardiovascular magnetic resonance imaging. These images showed asymmetrical septal hypertrophy with maximal left ventricular end-diastolic wall thickness of 25 mm. Following administration of gadolinium, areas of hyperenhancement were seen in the anterior, anteroseptal and lateral walls. This is the first report of focal gadolinium hyperenhancement in hypertrophic cardiomyopathy due to Noonan syndrome and suggests that myocardial fibrosis can be imaged by MR hyperenhancement as seen previously in sarcomeric hypertrophic cardiomyopathy.     

T Wave Complexity in Patients with Hypertrophic Cardiomyopathy

The complexity of the T wave assessed by principal component analysis (PCA) has been proposed to reflect obnormal repolarization, which may be arrhythmogenic. To determine whether PCA can differentiate patients with hypertrophic cardiomyopathy (HCM) from normal subfects and whether PCA is of prognostic importance in HCM, 112 patients with HCM (41 ±14 years, 64 males) and 72 healthy subjects (39 ± 9 years, 41 males) were studied. Patients with sinus node dysfunction, AV conduction block, flat T waves, QRS > 140 ms, and those < 15 years were excluded from this study. Standard 12-lead ECGs were recorded digitally using the MAC-VU system (Marquette Medical Systems). PCA parameters were computed using the QT Guard software package by Marquette. PCA ratio was significantly greater in HCM patients than in normal controls (23.9%± 12.4% vs 16.1%± 7.6%, P < 0.0001) and was correlated with QT-end dispersion (r = 0.24. P = 0.01) and QT peak (Q point to T peak) dispersion (r = 0.35, P < 0.0001). HCM patients with syncope (n = 23) had increased PCA ratios compared with those without syncope (29.1%± 11.5% vs 22.5%± 12.3%, P = 0.01). PCA ratio was similar in patients with and without nonsustained ventricular tachycardia on Holter (25.9%± 11.4% vs 22.7%± 12.1%, P = 0.2), as well as in patients treated with amiodarone or sotalol versus those not on therapy. In conclusion, assessment of the complexity of the T wave by PCA differentiates HCM patients from normal subjects. PCA ratio correlated with QT dispersion and an increased PCA ratio was associated with a history of syncope in HCM.     

Device therapy in hypertrophic cardiomyopathy

With increasing awareness of the condition and particular attention being paid to family screening, the number of patients being diagnosed with hypertrophic cardiomyopathy is increasing. Although the majority of patients remain at low risk for sudden cardiac death, all patients need to undergo rigorous and ongoing risk factor stratification in order to best identify those at high risk. Although implantable cardioverter–defibrillators have proven to be effective in the prevention of sudden cardiac death, careful consideration of device implantation in high-risk patients is necessary in view of the potential for device complications and their impact on quality of life.     

Infantile Hemangiomas,Retinopathy of Prematurity and Cancer: A Common Pathogenetic Role of the β‐Adrenergic System

The serendipitous demonstration that the nonselective β‐adrenergic receptor (β‐AR) antagonist propranolol promotes the regression of infantile hemangiomas (IHs) aroused interest around the involvement of the β‐adrenergic system in angiogenic processes. The efficacy of propranolol was related to the β₂‐AR blockade and the consequent inhibition of the production of vascular endothelial growth factor (VEGF), suggesting the hypothesis that propranolol could also be effective in treating retinopathy of prematurity (ROP), a retinal pathology characterized by VEGF‐induced neoangiogenesis. Consequent to the encouraging animal studies, a pilot clinical trial showed that oral propranolol protects newborns from ROP progression, even though this treatment is not sufficiently safe. Further, animal studies clarified the role of β₃‐ARs in the development of ROP and, together with several preclinical studies demonstrating the key role of the β‐adrenergic system in tumor progression, vascularization, and metastasis, prompted us to also investigate the participation of β₃‐ARs in tumor growth. The aim of this review is to gather the recent findings on the role of the β‐adrenergic system in IHs, ROP, and cancer, highlighting the fact that these different pathologies, triggered by different pathogenic noxae, share common pathogenic mechanisms characterized by the presence of hypoxia‐induced angiogenesis, which may be contrasted by targeting the β‐adrenergic system. The mechanisms characterizing the pathogenesis of IHs, ROP, and cancer may also be active during the fetal–neonatal development, and a great contribution to the knowledge on the role of β‐ARs in diseases characterized by chronic hypoxia may come from research focusing on the fetal and neonatal period.     

The usual suspects in sudden cardiac death of the young: a focus on inherited arrhythmogenic diseases

Up to 14,500 young individuals die suddenly every year in Europe of cardiac pathologies. The majority of these tragic events are related to a group of genetic defects that predispose the development of malignant arrhythmias (inherited arrhythmogenic diseases [IADs]). IADs include both cardiomyopathies (hypertrophic cardiomyopathy, arrhythmogenic right ventricular cardiomyopathy, dilated cardiomyopathy) and channelopathies (long QT syndrome, short QT syndrome, Brugada syndrome and catecholaminergic polymorphic ventricular tachycardia). Every time an IAD is identified in a patient, other individuals in his/her family may be at risk of cardiac events. However; if a timely diagnosis is made, simple preventative measures may be applied. Genetic studies play a pivotal role in the diagnosis of IADs and may help in the management of patients and their relatives.     

Role of drugs and devices in patients at risk of sudden cardiac death

The search for effective treatment for preventing sudden cardiac death (SCD) initially started with anti‐arrhythmic agents in high‐risk patients, but the use of randomized controlled trials clearly led to the conclusion that an approach based on anti‐arrhythmic agents is not useful, and sometimes potentially harmful (the risk of arrhythmic death was increased up to 159% in CAST study). Today the approach to SCD prevention includes considering both the setting of patients who have already presented a cardiac arrest or a malignant ventricular tachyarrhythmias (secondary preventions of SCD) and the much broader setting of primary prevention in patients at variable degrees of identifiable risk. For secondary prevention of SCD, implantable cardioverter defibrillation is now the standard of care (the risk of overall mortality may be reduced by 20–31%), and anti‐arrhythmic agents, specifically amiodarone, have only a complementary role (for reducing device activations or for preventing atrial fibrillation). For primary prevention of SCD in high‐risk patients, cardioverter defibrillators have nowadays specific indications in patients with left ventricular dysfunction (often in combination with cardiac resynchronization therapy), where the risk of overall mortality may be reduced by 23–54%. For the large number of subjects who have some risk of SCD, but are not identified as at high risk of SCD, a series of drugs could exert a favorable effect (beta‐blockers, angiotensin‐converting enzyme inhibitors, angiotensin receptor blocker agents, statins, omega‐3 fatty acids and aldosterone antagonists), and for some of them evidence is emerging, from subgroup analysis, of possible SCD prevention capabilities.     

Increased type I collagen synthesis in victims of sudden cardiac death due to idiopathic myocardial fibrosis

Abstract

Aims. Idiopathic myocardial fibrosis (IMF) was observed to be the most prevalent autopsy finding in the victims of sudden cardiac death (SCD) under the age of 40 years in the FinGesture cohort. To elucidate further the mechanisms of IMF, we examined the collagen composition from the myocardial samples taken from the victims of IMF-associated SCD.

Methods. Eighteen cases with IMF as a cause of death, confirmed by autopsy, were selected for the analysis. Controls (n = 27) included were cases in whom no cardiac or non-cardiac disease could be found as a cause of unexpected death at autopsy. In addition to conventional histological examination, immunohistochemical staining of procollagens I and III (PINP and PIINP), mature collagen III (IIINTP), and the cross-linked collagen I degradation product (ICTP) were performed.

Results. Increased accumulation of PINP was observed in the fibrotic tissue of the IMF cases in comparison with control samples. In contrast, type III collagen was not as frequently expressed in the fibrotic areas.

Conclusion. Myocardial accumulation of PINP in the victims of IMF-associated SCD indicates increased type I collagen synthesis. Future studies on the role of circulating type I collagen biomarkers are needed to study further the implications of the described association.     

Ventricular fibrillation and sudden cardiac arrest in apical hypertrophic cardiomyopathy: Two case reports

BACKGROUNDApical hypertrophic cardiomyopathy (HCM) is considered to have a benign prognosis in terms of cardiovascular mortality. This serial case report aimed to raise awareness of ventricular fibrillation (VF) and sudden cardiac death (SCD) in apical HCM. CASE SUMMARYHere we describe two rare cases of apical HCM that presented with documented VF and sudden cardiac collapse. These patients were previously not recommended for primary prevention using implantable cardioverter-defibrillator (ICD) therapy based on current guidelines. However, both received ICD therapy for the secondary prevention of SCD.CONCLUSIONThese cases illustrate serious complications including VF and aborted sudden cardiac arrest in apical HCM patients who are initially not candidates for primary prevention using ICD implantation based on current guidelines.     

扩张型心肌病QT间期离散度测定及临床意义

目的探讨扩张型心肌病(DCM)、QT间期离散度(QTd)、校正QT间期(QTcd)水平及临床意义.方法测量60例DCM同步12导联心电图,分析QTd、QTcd变化,并与60例正常人对照.结果QTd、QTcd比较,DCM组高于对照组(P＜0.01);心源性猝死组高于存活组和进行性心力衰竭死亡组(P＜0.05);室性心动过速组显著高于室性早搏组(P＜0.05)和无室性心律失常组(P＜0.01),而室性早搏组又高于无室性心律失常组(P＜0.05);NYHAⅢ～Ⅳ级患者高于NYHAⅠ～Ⅱ级患者.QTd＞110ms组室速、心源性猝死和NYHAⅢ～Ⅳ级发生率显著高于QTd≤110ms组(P＜0.01或P＜0.05),而射血分数、短轴缩短率无差异;多元线性回归分析示QTd、QTcd与NYHA分级、室性心律失常、心源性猝死相关,与射血分数、短轴缩短率不相关.结论DCM患者存在QTd、QTcd变化,QTd、QTcd的增加可作为预测DCM恶性室性心律失常的敏感指标,也是发生心源性猝死的重要预测指标.QTd与NYHA分级相关而与射血分数、短轴缩短率无关.