Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy: A Review

MARCUS, F.I., et.al .: Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy: A Review . Right ventricular dysplasia is being recognized with increasing frequency. It should be considered as a cause of ventricular tachycardia of left bundle branch block configuration and/or sudden unexpected death particularly during exercise in young men. The electrocardiogram (ECG) may show anterior precordial T wave inversion, particularly in lead V₂ and/or a QRS complex duration ≥ 110 ms in the right precordial leads. Echocardiographic studies focusing on the size and wall-motion abnormalities of the right ventricle are useful in confirming the diagnosis. Radionuclide angiography usually shows a moderately or markedly depressed right ventricular ejection fraction with normal or relatively well preserved left ventricular function. Cinemagnetic resonance imaging demonstrates abnormal fatty infiltration of the right ventricular myocardium and can show increased right ventricular dimensions as well as wall-motion abnormalities. Contrast ventricular angiography remains the gold standard to establish the diagnosis but must be performed with appropriate views and with care to avoid ventricular premature beats. Quantitative analysis of right ventricular dimensions can be performed in selected centers. Three-dimensional echocardiography is a promising approach to evaluate right ventricular wall-motion abnormalities as well as to demonstrate enlargement. The etiology and pathogenesis of this condition is not clear. A familial incidence has been well-documented in certain areas and an abnormal gene has been identified. Sporadic cases are the most common. In contrast to Uhl's anomaly, characterized pathologically by areas of paper thin myocardium, the right ventricular free wall is minimally decreased in thickness. Histologically there appears to be a replacement of musculature by fatty tissue. Medical therapy with sotalol or amiodarone, or combination therapy (Class Ic drugs plus beta-blocking drugs, or amiodarone plus beta-blocking drugs) is frequently effective in preventing recurrent ventricular tachycardia. Ablation using radiofrequency (RF) or direct current (DC) energy is reserved for patients who are unresponsive or intolerant of antiarrhythmic drugs. Ventricular arrhythmia recurrence of different morphology is not uncommon after apparent successful ablation. There appears to be a lower rate of successful ablation using RF energy. However, patients with this condition who have been resuscitated from sudden cardiac death or those refractory to medical treatment are candidates for ablation, implantation of an automatic cardioverter defibrillator, or cardiac transplantation. Surgery consisting of total disconnection of the right ventricle is a promising therapeutic modality.     

Epsilon Wave in Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy

Background: Epsilon wave is a major criteria for arrhythmogenic right ventricular (RV) dysplasia/cardiomyopathy (ARVD/C). We sought to study systematically characteristics of Epsilon wave in ARVD/C patients from the southern Chinese population.
Methods: The population included 49 patients with ARVD/C meeting the diagnostic criteria. They were analyzed for the value of different electrocardiogram (ECG) criteria including Epsilon wave, the ones of 24-hour Holter recording, signal-averaged ECG, and echocardiography to learn the correlation between Epsilon wave and other variability with the use of nonparametric test. A probability value of ≤0.05 was considered significantly different.
Results: It shown that the detection rate of Epsilon wave was significantly higher in probands (65%) than involved family members (22%), P = 0.03. In the conventional as well as Fontaine leads, its detection rate were 18 (37%) and 28 (57%), respectively. The prevalence of diffuse right ventricle involvement, T-wave inversion and signal-averaged ECG are significantly different between the ARVD/C patients with Epsilon wave and without Epsilon wave.
Conclusion: It is significantly correlated between Epsilon wave and the progressive ARVD/C.     

致心律失常性右室心肌病心房重塑及其临床特征分析

目的：致心律失常性右室心肌病（ARVC）是一种少见的遗传性器质性心肌病,既往认为ARVC主要累及左右心室,对心房重塑的影响尚不明确。本横断面研究旨在明确ARVC中心房重塑的发生率及临床特征。方法：本研究纳入2016-2020年我院诊断明确的ARVC患者40例,详细收集所有患者临床资料、心超结果,其中17例患者完善了心脏磁共振检查。分析患者心超及心脏磁共振相关心室、心房功能和结构参数。结果：本研究发现26例发生了右房增大(65%),15例发生了左房增大(37.5%),14例发生了双房增大(35%)。其中6例患者发生了房颤(15%),2例发生了房扑(5%)。心房重塑在ARVC患者中较为常见,心房重塑的ARVC患者房性心律失常事件发生率显著增加。右心房重塑常常伴随右心室扩张、心脏功能不全,右心室心外膜脂肪及MACE事件增加。结论：本研究提示ARVC不仅累及左右心室,对左右心房亦有影响,心房重塑可能作为ARVC的重要病理环节参与ARVC的进展及预后。     

Twenty-Seven-Year Follow-up of Arrhythmogenic Right Ventricular Dysplasia

OBATA, H., et al. : Twenty-Seven-Year Follow-up of Arrhythmogenic Right Ventricular Dysplasia. This case report describes clinical features, especially of surface ECG changes, observed for 27 years in a patient with arrhythmogenic right ventricular dysplasia (ARVD). The course of this patient was characterized by progressive deterioration of right ventricular function and progression of delayed potentials (so-called epsilon waves) following QRS complexes. However, the relation between ventricular arrhythmias and ECG changes or the degree of right ventricular abnormality was difficult to discern.     

Entrainment of Ventricular Tachycardia in Arrhythmogenic Right Ventricular Tachycardia

In two patients with arrhythrnogenic right ventricular dysplasia (ARVDJ, sustained ventricular tachycardia (VT) was induced by programmed stimulations during serial drug testings. One patient had five and the other had two VT morphologies, and the sites of origin were determined by endocardial catheter mappings. When overdrive pacing was performed, constant fusion in the QflS complex was observed in the two patients. Constant fusion of a different degree was also observed at different paced cycle lengths. Both patients had dilated right ventricles and wall-motion abnormality, and the diagnosis of ARVD was further confirmed by the specimen resected at the site of origin of VT. Therefore, VT in ARVD can be entrained and reentry is the most likely mechanism of such VT.     

Cardiac Sarcoidosis Masquerading as Right Ventricular Dysplasia

Patients with cardiac sarcoidosis may present with clinical and morphological features similar to arrhythmogenic right ventricular dysplasia (ARVD) or cardiomyopathy (ARVC). Three cases of cardiac sarcoidosis are presented that clinically mimicked ARVD or ARVC until a pathology diagnosis of sarcoidosis was made at biopsy or autopsy. A diagnostic distinction, while often difficult to make, is important since treatment with corticosteroids may benefit those with sarcoidosis but is not expected to be useful in cases with ARVD or ARVC. (PACE 2003; 26[Pt. I]:1498–1503)     

致心律失常性右室心肌病的临床研究

目的：探讨致心律失常性右室心肌病（ARVC）的临床特点、诊断和治疗。方法：回顾分析2003～2007年入住复旦大学附属中山医院的58例ARVc患者的临床资料。分析ARVc的临床表现及心电图、超声心动图、MRI、电生理检查等,评价ARVC的检查手段及治疗方法。结果：58例患者多表现为反复胸闷、心悸。心电图、超声心动图及MRI均有特征性改变。治疗以药物为主,需长期维持治疗。结论：ARVC临床表现隐匿,以室性心律失常为主要表现,发作时常伴严重血流动力学障碍。Epsilon波和右胸导联QRS间期延长两者结合有助于ARVC的筛选和诊断。右室心尖部和流出道均为ARVC病变的好发邵位。射频消融治疗可行。     

Demonstration of Entrainment and Presence of Slow Conduction During Ventricular Tachycardia in Arrhythmogenic Right Ventricular Dysplasia

During VT in two cases with arrhythmogenic right ventricular dysplasia, entrainment criteria, constant fusion beats except for the last entrainment beat, progressive fusion, and a localized conduction block associated with interruption of VT, were demon strated with rapid ventricular pacing performed during VT. Furthermore, a long conduction interval was present during entrainment from the pacing site to the earliest activation site during VT. indicating the presence of a slow conduction area. VT in these cases was, thus, due to reentry with an area of slow conduction within the circuit.     

An Unusual Cause of Abnormal Intrathoracic Impedance in a Patient with Arrhythmogenic Right Ventricular Cardiomyopathy

A device interrogation for a 32‐year‐old woman with arrhythmogenic right ventricular cardiomyopathy and an implantable cardioverter‐defibrillator capable of monitoring intrathoracic impedance demonstrated a dramatic increase in her OptiVol Fluid index levels in the absence of clinical heart failure. The timing of her intrathoracic impedance changes correlated with plasma volume changes during an uneventful pregnancy without cardiovascular complications. The strengths and limitations of intrathoracic impedance are described in the context of the physiology of pregnancy. (PACE 2010; 34:e60–e63)     

致心律失常性右室心肌病的临床及超声心动图特点

目的探讨致心律失常性右室心肌病（ARVC）的临床和超声心动图特点。 方法收集、查阅1993年～2005年我院心内科7例诊断为ARVC的入院病例资料,分析其临床资料及超声心动图特点。 结果7例ARVC患者中6例以室性心律失常发病,1例为家系检查时发现。1例猝死,1例心力衰竭,4例晕厥,1例无症状。所有患者均做了心电图、二维超声心动图,部分患者做了动态心电图、心室核素造影、右心室造影。二维超声心动图检查：所有患者均有右心室扩大,4例右室流出道扩张,1例左室略大;5例右室壁运动弥漫性减弱,2例局限性减弱,2例右室室壁瘤形成,3例室间隔运动异常;所有患者三尖瓣、肺动脉瓣口前向血流速度均减慢,右房内均见反流束,反流压差均较低。 结论（1）ARVC患者的临床表现较为复杂多样,典型者常以反复发作性室性心动过速、晕厥、猝死为其首发症状;部分呈家族遗传倾向;（2）超声心动图显示有右心室扩大、右室流出道扩张伴右心室壁弥漫性或局限性变薄、动度减弱,部分患者左心室受累;（3）超声心动图简便、易行,但在诊断ARVC时需除外其他致右室扩大的病变。     

致心律失常性右室心肌病14例临床分析

目的：提高对致心律失常性右室心肌病（ARVC）的诊断、治疗及预后的认识。方法：对1993－2001年入住复旦大学附属中山医院的14例致心律失常性右室心肌病的病例进行回顾性分析并随访。观察ARVC的临床表现及心电图、超声心动图、电生理检查等表现，评价ARVC的治疗方法和预后。结果：14例患者均以室性心律失常起病。心电图及超声心动图是正确诊断的重要方法。随访中有3例死亡，2例出现右心衰竭。1例在射频消融治疗后无须药物治疗室性心律失常明显减少。其余均需药物长期维持治疗。结论：致心律失常性右室心肌病以室性心律失常为主要表现，发作时常伴严重血流动力学障碍。心电图有特征性改变，其诊断主要依靠超声心动图。治疗以药物为主，射频消融未显示优越性。晚电位阳性、有过阿斯综合征、右室整体收缩功能异常者预后不良。     

Atrial Epicardial Pacing with Long Stimulus to P Wave Interval in a Patient with Arrhythmogenic Right Ventricular Dysplasia Complicated by Right Atrial Thrombosis

Atrial epicardial pacing with a long stimulus to P wave interval in a patient with arrhythmogenic right ventricular dysplasia complicated by right atrial thrombosis is discussed. Arrhythmogenic right ventricular dysplasia (ARVD) is associated with a high incidence of malignant ventricular arrhythmias. Most patients with ARVD need antiarrhythmic drugs, catheter ablation, or an implantable cardioverter defibrillator. We report a patient with ARVD in whom effective treatment with sotalol caused severe, symptomatic sinus bradycardia requiring permanent pacing. Due to leftward displacement of the right ventricle and the presence of two thrombi in the right atrium, an epicardial atrial lead and AAI pacemaker were implanted. A long stimulus to P wave interval caused by severe dilatation of the right atrium was recorded. During a 6 months of follow-up on sotalol treatment there were neither ventricular tachycardia (VT) attacks nor pacing problems.     

Distinctive Response of Arrhythmogenic Right Ventricular Disease to High Dose Isoproterenol

HAISSAGUERRE, M., ET AL.: Distinctive Response of Arrhythmogenic Right Ventricular Disease to High Dose Isoproterenol. Arrhythmogenic right ventricular disease is a potential cause of ventricular arrhythmias. Diagnosis is important due to the risk of sudden death, particularly as first symptom. Diagnosis is based on the angiographic demonstration of abnormal right ventricular morphology and function, while the sensitivity of noninvasive tests is relatively low. Following a particular observation studied in 1984, we prospectively assessed the diagnostic value of high dose isoproterenol infusion in 44 patients with an angiographically determined arrhythmogenic right ventricle. A continuous infusion of isoproterenol (8–30 µg/min) was administered during a 3-minute period, regardless of the obtained heart rate. In a control group of 50 patients without structural heart disease, isoproterenol induced a monomorphic ventricular tachycardia salvo in only one patient (2%). In patients with an arrhythmogenic right ventricle, isoproterenol induced one or more ventricular tachycardia runs in 39/44 cases (88%): one triplet in three patients, several runs in 23 patients and a sustained ventricular tachycardia in 13 patients. Arrhythmia was polymorphous in 85% of cases, but left bundle branch block morphelogy was the predominant pattern. In conclusion, high dose isoproterenol is a highly sensitive test for the diagnosis of arrhythmogenic right ventricular disease.     

Arrhythmogenic Right Ventricular Cardiomyopathy

Arrhythmogenic right ventricular cardiomyopathy (ARVC) has evolved from postmortem pathology at to a diagnosable clinical condition, and holds promise for definitive genetic diagnosis. Its prevalence is between 1/1,000 and 1/5,000, with 10% of deaths occurring before age 19 and 50% before age 35. When analyzed against age-specific norms, the electrocardiography (ECG) and signal-averaged ECG (SAECG) have moderate sensitivity for ARVC. Endomyocardial biopsy in young individuals with ARVC demonstrates fibrosis more frequently than fatty infiltration, and is convincing for the diagnosis in approximately 1/3 (often in patients who would not otherwise be diagnosed), but has a recognized complication rate of 2%. Newer technologies of magnetic resonance imaging and voltage mapping hold promise but require further assessment in young individuals suspected to have ARVC. Genetic diagnosis of one of several desmosomal mutations is positive in an approximately 50% of suspected patients, and may provide clues to the pathophysiology of the disease. Serial studies of myocardial function, ambulatory electrocardiography, and SAECG parameters may be useful in risk stratification of identified patients, although their applicability to genetically identified asymptomatic individuals has not been studied.