致心律失常性右心室心肌病致病基因研究进展

致心律失常性右心室心肌病（arrhythmogenic right ventricular cardiomyopathy,ARVC）是一种遗传性心肌病,好发于青少年,国外报道发病率为0．2‰-4．4‰,男性居多。病理特征为右心室心肌逐渐被脂肪和纤维脂肪组织替代,导致右心室的结构和功能异常,尚可累及室间隔及左心室游离壁。     

Genetics of arrhythmogenic right ventricular cardiomyopathy

Recent advances in molecular genetics of arrhythmogenic right ventricular cardiomyopathy (ARVD) are reviewed. In particular, the finding of mutations in the gene coding for cardiac ryanodine receptor (hRYR2), both in patients affected with ARVD2 and in patients affected with catecholaminergic ventricular arrhythmias or with familial ventricular tachyarrhythmia, is discussed. Novel data support the hypothesis that apoptosis may be a key step in molecular pathogenesis of ARVDs. A series of studies on drugs with apparent protective effect against apoptosis in myocardial cells might open new perspectives in the therapeutic approach.     

磁共振成像在致心律不齐性右室型心肌病的诊断价值

目的回顾性分析27例致心律不齐性右室型心肌病（ARVC）的磁共振成像（MRI）表现,探讨MRI在ARVC的诊断与预后判断中的价值。方法按照1994年WHO关于ARVC的诊断标准,2004年10月至2006年6月共27例临床诊断或病理确诊为ARVC（6例行心脏移植术）,男21例,女6例,平均年龄37．4（15～67）岁。采用1．5T超导MRI扫描仪对心脏形态（脂肪浸润、房室大小）、功能（室壁局部与整体运动功能）、心肌灌注与心肌存活等方面进行综合评价。结果形态学：88．89％（24／27）的病例MRI提示心肌脂肪浸润,62．96％（17／27）右室壁变薄,62．96％（17／27）右室心尖肌小梁明显粗乱,66．67％（18／27）右室流出道扩张,51．85％（14／27）右室心尖扩张,66．67％（18／27）右室下壁及游离壁扩张,40．74％（11／27）合并右房增大。心脏功能：18．52％（5／27）的病例右室局部运动功能异常,70．37％（19／27）整体运动功能异常,右室平均射血分数（EF）35％。40．74％（11／27）的患者合并左室扩大并室壁收缩运动明显减弱。心肌首过灌注示10．52％（2／19）的患者左室受累,36．84％（7／19）的患者左室和右室壁出现异常强化,提示心肌纤维或胶原变性。右室壁强化区域主要位于右室游离壁和右室流出道肌壁,左室则主要位于左室侧壁,少数合并左室心尖或室间隔,5例左室侧壁异常强化经术后病理证实为纤维组织。仅1例表现为右室流出道增宽,但左室心肌显著变薄,收缩运动明显减弱;有3例右室MRI无阳性表现,其中2例左室侧壁室壁变薄并运动异常,延迟显像为异常强化,另1例表现为类似扩张型心肌病样改变。结论MRI高度的软组织对比与多序列成像可对ARVC进行全面诊断与预后评价,但少数以左室异常表现为主而无明显或仅轻微右室异常的病例,MRI易误诊,其左室侧壁段的纤维化为ARVC相对特征表现。右室整体运动异常、广泛纤维脂肪浸润、合并左室扩张并运动异常为其预后不良的指标。     

致心律失常性右心室心肌病的治疗学进展

致心律失常性右心室心肌病（ arrhythmogenic right ventricular cardiomyopathy, ARVC ） 是一类遗传性心肌病，常表现为家族聚集性，现已发现有8个基因的突变与ARVC的发病有关，其中大多数为编码桥粒蛋白的基因。该病的外显率不一并且进行性发展，临床表现多样，可以毫无症状，也可以表现为频繁的室性心律失常，甚至以猝死为首发表现，病程晚期出现严重的心脏扩大以及心力衰竭症状。     

Risk stratification in arrhythmogenic right ventricular cardiomyopathy

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a genetic cardiomyopathy characterized by myocyte death and fibrofatty replacement mostly in the right ventricle. It is a leading cause of sudden cardiac death (SCD) in individuals under the age of 35 years. The main goal in the treatment of the disease is the prevention of SCD. An implantable cardioverter-defibrillator (ICD) is the only proven life-saving therapeutic option able to improve survival in ARVC patients. This therapy is not free from side effects and it accounts for a relatively high rate of morbidity because of the occurrence of inappropriate ICD interventions and of complications, both at implantation and during the follow-up. In recent years, the approach to ICD implantation has been changing on the basis of new emerging data on risk stratification. The usefulness of ICD implantation for secondary prevention has been definitively proven; the most challenging question is how to treat patients with no history of previous cardiac arrest or hemodynamically unstable ventricular tachycardia (VT). The value of ECG abnormalities, syncope, VT, and right/left ventricular involvement as predictors of SCD has been assessed in different studies with the purpose of better defining risk stratification in ARVC. Nevertheless, in spite of the growing amount of data, primary prevention in ARVC patients remains mostly an individual decision.     

碎裂QRS波在致心律失常性右心室心肌病诊断中的价值

Objective To evaluate diagnostic value of fragmented QRS complex (fQRS)in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC). Methods Forty-three patients [33 men, aged (40. 4 ± 13.9)years]meet the ISFC/ESC diagnostic criteria for ARVC were enrolled in this study. A standard twelve-lead electrocardiogram was obtained during the resting status. Characteristics of fQRS were detailedly studied by three doctors independently. A comparison of the prevalence among fQRS, epsilon wave and T wave inversion( TWI )in the right precordial leads exceeding V3 was done. Results Most fQRS could be found in the inferior leads (44. 3% ) and the right precordial leads (24. 2% ). Within the QRS complex, the prevalence of fQRS in the R wave was significantly higher than it in the S wave(58. 4% vs 32. 9% ,Z =4. 30,P ＜0. 01 ).fQRS could be found in a total of 31 of 43 cases( mean 4. 6 ± 1.7 ( range 2 to 9) per patient). The prevalence of fQRS was significantly higher than that of epsilon wave ( 73.8% vs 30. 2%, Z = 3.67, P ＜ 0. 01 ) and TWI (73.8% vs41.9% ,Z =2. 61 ,P＜0. 01 ). Conclusion fQRS was a common electrocardiographic abnormality,and most was found in the inferior and right precardial leads in patients with ARVC. It may be used as an important noninvasive preliminary screening electrocardiographic criteria.     

碎裂QRS波在致心律失常性右心室心肌病诊断中的价值

目的评价碎裂QRS波（fQRs波）在致心律失常性右心室心肌病（ARVC）诊断中的价值。方法43例符合ARVC诊断标准的患者,男性33例,平均年龄（40．4±13．9）岁。采集临床资料,记录静息状态下标准12导联心电图,描述fQRs波的心电图特征,判断是否存在fQRs波、epsilon波和右胸前导联T波倒置（TWI）并比较其阳性率之间的差异。结果本组患者fQRs波以下壁导联（44．3％）和右胸前导联（24．2％）最为多见。QRS波中,fQRs波见于R波者多于S波者（58．4％对32．9％,Z=4．30,P〈0．01）。共31例患者判断为fQRS波阳性,2～9（4．6±1．7）个／例。fQRs波阳性率较epsilon波（73．8％VS30．2％,Z=3．67,P〈0．01）和TWI（73．8％对41．9％,Z=2．61,P〈0．01）显著增高。结论fQRs波阳性是ARVC患者常见的心电图异常,常见于下壁和右胸前导联,可作为提示诊断的无创心电指标。     

A case of arrhythmogenic right ventricular cardiomyopathy

The present report describes a 40-year-old woman with a long history of monomorphic ventricular tachycardia and left bundle branch block. She was treated with various antiarrhythmic agents; ventricular tachycardia ablation was attempted and an automatic implantable cardioverter defibrillator was implanted. Three-dimensional echocardiography clearly demonstrated features of arrhythmogenic right ventricular cardiomyopathy, including marked right ventricular (RV) dilation, decreased RV systolic function and thinning of the RV free wall. Other RV morphological abnormalities included excessive trabeculations and a localized apical aneurysm. Two years later, the patient developed symptoms of congestive heart failure. Despite maximal medical therapy, her clinical condition continued to deteriorate and she was referred for heart transplantation. Results of the pathology of her explanted heart confirmed this rare diagnosis. She presented with an unusual clinical course for arrhythmogenic right ventricular cardiomyopathy, which was complicated by progressive congestive heart failure and ultimately required heart transplantation. Three-dimensional echocardiography identified the structural abnormalities related to this rare disease.     

Echocardiographic assessment of arrhythmogenic right ventricular cardiomyopathy

OBJECTIVE—To evaluate new echocardiographic modes in the diagnosis of arrhythmogenic right ventricular cardiomyopathy (ARVC).
DESIGN—Prospective observational study.
SETTING—University Hospital.
SUBJECTS—15 patients with ARVC and a control group of 25 healthy subjects.
METHODS—Transthoracic echocardiography included cross sectional measurements of the right ventricular outflow tract, right ventricular inflow tract, and right ventricular body. Wall motion was analysed subjectively. M mode and pulsed tissue Doppler techniques were used for quantitative measurement of tricuspid annular motion at the lateral, septal, posterior, and anterior positions. Doppler assessment of tricuspid flow and systemic venous flow was also performed.
RESULTS—Assessed by M mode, the total amplitude of the tricuspid annular motion was significantly decreased in the lateral, septal, and posterior positions in the patients compared with the controls. The tissue Doppler velocity pattern showed decreased early diastolic peak annular (E_A) velocity and an accompanying decrease in early (E_A) to late diastolic (A_A) velocity ratio in all positions; the systolic annular velocity was significantly decreased only in the lateral position. Four patients had normal right ventricular dimensions and three were judged to have normal right ventricular wall motion. The patient group had also a significantly decreased tricuspid flow E:A ratio.
CONCLUSIONS—Tricuspid annular measurements are valuable, easy to obtain, and allow quantitative assessment of right ventricular function. ARVC patients showed an abnormal velocity pattern that may be an early but non-specific sign of the disease. Normal right ventricular dimensions do not exclude ARVC, and subjective detection of early changes in wall motion may be difficult.


Keywords: annular motion; diastolic dysfunction; right ventricular function; tissue Doppler     

致心律失常性右心室心肌病的造影诊断

目的 评价心血管造影术(angiocardiography,ACG)对致心律失常性右心室心肌病(arrhythmogenicright ventricular cardiomyopathy,ARVC)的诊断价值和限度.方法 对11例临床确诊ARVC的患者行左心室、右心室造影,观察其形态及运动功能(特别是漏斗流出道、心尖小梁部以及下壁).结果 11例均行右心室造影,形态上表现为漏斗流出道扩张,其中7例为局限性扩张,3例为局限性扩张并囊袋状突出,1例为局限性扩张并叠盘状影;心尖小梁部8例叠盘状影,2例囊袋状突出,1例叠盘状影并囊袋状突出;下壁9例囊袋状突出,1例叠盘状影,1例囊袋状突出并叠盘状影.在运动功能异常方面,运动减弱最明显,分别见于漏斗流出道8/11,心尖小梁部10/11,下壁10/11;其次为无运动,分别发生在漏斗流出道2/11,心尖小梁部1/11,下壁1/11.1例还另行左心室造影,表现为:小梁粗大,心尖囊袋状突起,切迹,室间隔光滑.结论 右心室造影,征象明确,只要抓住发育不良三角形态及功能变化,就能作出正确诊断.ACG是ARVC诊断和鉴别诊断的重要依据.     

Evolution of left ventricular involvement in arrhythmogenic right ventricular cardiomyopathy

Left ventricular (LV) involvement in arrhythmogenic right ventricular cardiomyopathy (ARVC) is fairly well known, but the evolution of LV involvement during long-term follow-up has not been well documented. We describe such evolution in a patient followed for 9 years. Evolution was confirmed by a progressive perfusion defect of the LV wall in myocardial scintigrams and by the development of LV asynergy with ventricular aneurysm formation in left ventriculograms. As the right ventricle progressively enlarged, we concluded that ARVC is a diffuse and progressive myocardial disease that affects both ventricles.     

致心律失常性右室心肌病新观点

随着对致心律失常性右室心肌病(arrhythmogenic right ventricular cardiomyopathy,ARVC)研究的进展,目前已不再认为ARVC只是桥粒蛋白基因突变引起的一种累及右室的遗传性心肌病.ARVC可以由非桥粒蛋白的多种基因突变或非遗传因素引起,并且可以首先累及左室.因此,2019年制定ARVC诊断标准的国际专家组提出了该病的新的临床分型,并对2010年的诊断标准作出了新的评价.本文就ARVC的临床分型、致病基因、诊断及治疗研究进展等方面进行综述.     

Noninvasive risk stratification in arrhythmogenic right ventricular cardiomyopathy

The natural history of arrhythmogenic right ventricular cardiomyopathy is determined by the electrical instability of the dystrophic myocardium, which can precipitate arrhythmic cardiac arrest any time during the course of the disease and by the progressive myocardial loss that results in ventricular dysfunction and heart failure. Sudden death accounts for the majority of the fatal events but its occurrence is mostly unpredictable. There are no prospective and controlled studies assessing clinical markers that can predict the occurrence of life-threatening ventricular arrhythmias. However, the noninvasive risk profile, which emerges from retrospective analysis of clinical and pathologic series, is characterized by history of syncope, physical exercise, spontaneous ventricular tachycardia or ventricular fibrillation, right ventricular dysfunction, left ventricular involvement, right precordial negative T wave, right bundle branch block, QT-QRS dispersion, right precordial ST-segment elevation and late potentials. At present only QRS dispersion, history of syncope and right and/or left ventricular abnormalities at radionuclide angiography proved to be independent noninvasive predictors of sudden death.