新型磁共振对典型及早期致心律失常性右室心肌病诊断价值的探讨

目的 用有黑血技术的新型磁共振（MRI）对典型致心律失常性右室心肌病（ARVC）进行检查，以确定新型MRI诊断ARVC的特异性和敏感性，并通过对确诊的ARVC患的一级亲属行MRI检查，以探讨MRI对早期ARVC的诊断价值。方法 10例ARVC患（除1例猝死首诊外）及其7个家系的54名成员全部接受询问病史，体检，心电图，心脏超声等检查；10例临床患均接受MRI检查，分析和确定其影响特征及诊断条件，在此基础上对部分家系成员行MRI检查以发现早期ARVC患。结果 临床患有阵发性室性心动过速（8／8），晕厥（9／10），心力衰竭（3／10）和猝死（3／10）。心电图均有左束支传导阻滞型阵发性室性心动过速，心室晚电位（VLP）均阳性（8／8）。MRI检查显示临床患均有明显右心室（RV）扩大及室壁广泛强信号，经压脂处理后心肌信号呈岛状或连续中断，为特征性纤维脂肪替代影像，患均有RV运动减低或室壁瘤形成，部分伴左心室受累（3／8）。家系筛选发现8例异常，拟诊为早期ARVC，2例有心电图异常，2例VLP阳性。MRI显示，8例心室壁均有局限性纤维脂肪病的影像改变，4例有RV扩大，2例可疑扩大，6例RV心尖部血流淤滞现象。结论 带黑血技术的新型MRI是目前诊断ARVC和早期ARVC的最具特异性和敏感性的检查手段。     

Arrhythmogenic right ventricular cardiomyopathy with an initial manifestation of severe left ventricular impairment and normal contraction of the right ventricle

A case of arrhythmogenic right ventricular cardiomyopathy (ARVC) with an initial manifestation of severe impairment of the left ventricle (LV) and normal contraction of the right ventricle (RV) is presented. A 43-year-old man was admitted to hospital because of congestive heart failure following a common cold. The LV function was diffusely and severely hypokinetic. Coronary arteriogram revealed normal vessels. An endomyocardial biopsy specimen obtained from the RV septum revealed mild infiltration of lymphocytes with focal myocytes necrosis and so healing myocarditis was suspected. The specimen did not include any fatty replacement of myocytes. Since then, the patient suffered from recurrent congestive heart failure as well as nonsustained ventricular tachycardia and required frequent hospitalization. Progressive impairment, dilation, and thinning of both ventricles were observed on serial echocardiographic examinations. Although the RV gradually enlarged and became impaired, severe dilatation and impairment of the LV has always been predominant in the patient's clinical course. After medical follow-up for 10 years, he died suddenly of ventricular fibrillation and pump failure. The autopsy revealed extensive fibrofatty replacement of myocytes in both the ventricles, extending from the outer layer to the inner layer of myocardium in the RV and to the middle layer in the LV. These features were compatible with arrhythmogenic right ventricular cardiomyopathy or perimyocarditis, although only the rightsided bundle of the interventricular septum was completely replaced by fatty tissue, which can not be explained as a sequel of perimyocarditis. Moreover, apoptosis was present in the myocyte nuclei of the myocardial layers bordering the area of fatty replacement. Therefore, myocarditis may have triggered or accelerated the process of apoptosis leading to ARVC.     

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。     

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.     

A case of right ventricular dilated cardiomyopathy, which involved left ventricle

A case of right ventricular dilated cardiomyopathy which also involved the left ventricle was reported. On health screening, a 16-year old woman was pointed out to have multifocal PVC and cardiomegaly. Subsequently, she was admitted to our hospital because of general fatigue. CTR was enlarged to 54.9% on chest X-ray. ECG showed LBBB-type PVC, right axis deviation, low voltage and T wave changes. On UCG, RVdD was dilated to 40 mm and LVdD was 37 mm. There was no finding of abnormality of the tricuspid valve. On cardiac catheterization, there was no shunt disease. Intracardiac pressure was normal. The end-diastolic volume index (ml/m2) of RV and LV was 196.7 and 67.4, respectively. And ejection fraction (%) was 20 and 40. Ventriculography revealed diffuse dilatation of the right ventricle. And lowered contractility existed not only in the right ventricle but also in the anterior and apical segment of the left ventricle. T(1)201 myocardial perfusion imaging showed irregular perfusion defect of the left ventricle. Endomyocardial biopsy revealed marked hypertrophy, partial atrophy, disarrangement of myocyte and interstitial fibrosis of the right ventricle. This case was considered to be right ventricular dilated cardiomyopathy. It seemed to be an intermediate form of dilated cardiomyopathy since it also involved the left ventricle. It was an interesting case to illustrate the spectrum of expression of cardiomyopathy.     

Relation between premature ventricular contraction site of origin (defined by radionuclide phase analysis) and subsequent left ventricular function

It has been suggested that the effect of a premature ventricular contraction (PVC) on left ventricular (LV) function depends on the site of origin of the PVC, and that the subsequent impairment of LV performance during a PVC may be more pronounced if baseline LV dysfunction is present. To evaluate these concepts, radionuclide angiographic phase image analysis of spontaneous PVCs was performed after acquisition of images from PVCs alone by a new gating procedure. The sites of the PVCs were localized to 1 of 3 right ventricular (RV) or 5 left ventricular (LV) regions by this method. LV function during PVCs was assessed and compared with baseline by noting the LV ejection fraction (EF) during PVCs, the difference between sinus LVEF and PVC EF, and the normalized PVC EF (PVC EF/sinus EF). Twenty-four patients had LV PVC sites and 19 had RV sites. LV function during a PVC appeared to be independent of either the ventricle of origin of the PVC or a specific site of origin within the ventricles. The resultant PVC ventricular function also appeared independent of sinus LVEF and sinus wall motion abnormalities. In addition, no correlation between coupling interval and any of the variables measured was demonstrated (although extremely short coupling intervals were not evaluated). These data suggest that the effects of PVCs on ventricular performance seen during ventricular ectopy are independent of the site of origin of the PVC, baseline wall motion abnormalities or PVC coupling interval in the population studied.     

Right atrial abnormalities in a patient with arrhythmogenic right ventricular cardiomyopathy without ventricular tachycardia

We describe a 59-year-old woman with sick sinus syndrome (SSS) and arrhythmogenic right ventricular cardiomyopathy (ARVC). Diagnosis of SSS was made because she had frequent episodes of sinus arrest with prolonged ventricular asystole. Cardiac images showed a dilated right atrium (RA) and a right ventricle (RV). Electroanatomical mapping of the RA showed extensive scarring with no recordable electrical potentials. Although she had frequent premature ventricular contractions, neither spontaneous ventricular tachycardia (VT) nor induced VT was observed. Microscopic examination of the RV indicated fibrofatty myocardium. Atrial arrhythmias associated with SSS may be the cause of symptoms in some cases of ARVC.     

Arrhythmogenic right ventricular cardiomyopathy/dysplasia: An update

Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is a genetic cardiomyopathy characterized by ventricular arrhythmias and structural abnormalities of the right ventricle (RV). The diagnosis is based on the International Task Force criteria. Cardiologists may not be aware of these diagnostic criteria for ARVC/D and may place too much importance on the results of MRI imaging of the right ventricle. Patients with ARVC/D usually have an abnormal 12-lead electrocardiogram, abnormal echocardiogram, and ventricular arrhythmias with a left bundle branch block morphology. If noninvasive testing suggests ARVC/D, invasive testing with an RV angiogram, RV biopsy, and electrophysiologic study is recommended. Once a diagnosis of ARVC/D is established, the main treatment decision involves whether to implant an implantable cardioverter-defibrillator. We also recommend treatment with β blockers. Patients with ARVC/D are encouraged to avoid competitive athletics. Recent advances in the understanding of the genetic basis of ARVC/D have revealed that ARVC/D is a disease of desmosomal dysfunction.     

Arrhythmogenic Right Ventricular Cardiomyopathy 2012: Diagnostic Challenges and Treatment

ARVC 2012 . The most common presentation of arrhythmogenic right ventricular cardiomyopathy (ARVC) is palpitations or ventricular tachycardia (VT) of left bundle branch morphology in a young or middle‐aged individual. The 12‐lead electrocardiogram may be normal or have T‐wave inversion beyond V₁ in an otherwise healthy person who is suspected of having ARVC. The most frequent imaging abnormalities are an enlarged right ventricle, decrease in right ventricular (RV) function, and localized wall motion abnormalities. Risk factors for implantable cardioverter defibrillator include a history of aborted sudden death, syncope, young age, decreased left ventricular function, and marked decrease in RV function. Recent results of treatment with epicardial ablation are encouraging. (J Cardiovasc Electrophysiol, Vol. 23 pp. 1149‐1153, October 2012)     

Comparison of ventricular function after Senning and Jatene procedures for complete transposition of the great arteries

Postoperative right (RV) and left ventricular (LV) volume characteristics in patients with complete transposition of the great arteries were studied to compare ventricular function after Senning and Jatene procedures and to analyze RV dimensional change during systole in patients after the Senning procedures. RV end-diastolic volume (EDV) was 181 +/- 74% of normal (mean +/- standard deviation) and RV ejection fraction (EF) was 0.48 +/- 0.09 in 15 patients who underwent the Senning procedure. In 9 patients who underwent the Jatene procedure, LVEDV was 152 +/- 27% of normal and LVEF was 0.61 +/- 0.09. One patient with aortic regurgitation, 1 with aortic regurgitation and residual ventricular septal defect, and 1 with aortic regurgitation and generalized LV wall hypokinesia of unknown cause had large LVEDVs. Pulmonary ventricular EDV and EF were within normal ranges except in the patients with persistent pulmonary hypertension, who had large EDVs and low EFs regardless of the anatomic type of ventricle, either the left or right. The study of RV dimensional change in the Senning group showed a reduced systolic shortening of the anteroposterior diameter compared with the preoperative transposition of the great arteries and normal. This reduced shortening may be related to postoperative adhesion of the RV free wall to the anterior chest wall and fixation of the atrium secondary to the intraatrial repair. In conclusion, systemic ventricular function after intraatrial repair for complete transposition of the great arteries is depressed by unavoidable residua and sequelae: persistent RV hypertension, anatomy of the right ventricle and, possibly, postoperative adhesions.(ABSTRACT TRUNCATED AT 250 WORDS)     

Prospective comparison of right and left ventricular stimulation for induction of sustained ventricular tachycardia

Thirty-eight patients who had sustained monomorphic ventricular tachycardia (VT) or sudden cardiac death underwent programmed ventricular stimulation. To assess the relative efficacy of right and left ventricular (RV and LV) stimulation, a tandem protocol with 1 to 4 extrastimuli and burst pacing was used. Each step of the protocol was performed in a rotating sequence at the RV apex, basal RV septum and LV apex. Sustained VT was induced from the RV apex in 26 patients, right ventricle (either site) in 27, and LV apex in 24, and spontaneous VT was reproduced from those sites in 11, 14 and 12 patients, respectively. In the 23 patients who had sustained VT induced from both ventricles, RV stimulation always required fewer or the same number of extrastimuli for induction. At every stage of the protocol, the cumulative yield of sustained VT was consistently greater from the right ventricle than from the left ventricle. After delivering 4 extrastimuli and burst pacing, LV stimulation only increased the yield of sustained VT by 1 patient, and spontaneous VT by 3 patients. Inducibility or noninducibility in the right ventricle generally predicted the same outcome in the left ventricle. Previously undocumented VT or ventricular fibrillation was induced from the right ventricle in 19 patients and from the left ventricle in 13. Thus, LV stimulation was less efficacious than RV stimulation. LV stimulation increased the yield over RV stimulation only minimally and did not reduce the number of extrastimuli required to induce sustained VT.     

Clinical profile of arrhythmogenic right ventricular cardiomyopathy in Chinese patients.

OBJECTIVE: To study the clinical profile of Chinese patients with arrhythmogenic right ventricular cardiomyopathy (ARVC). PATIENTS: Chinese patients who fulfilled the diagnostic criteria of ARVC proposed by the Task Force of the European Society of Cardiology and of the scientific council on cardiomyopathy of the International Society and Federation of Cardiology were recruited for analysis. METHODS: Clinical data of patients with ARVC including age, sex, family history, presenting symptoms, electrocardiograph (ECG), echocardiography, cardiac catheterization, magnetic resonance imaging (MRI), electrophysiology study (EPS) and therapeutic intervention were analyzed. RESULTS: Eleven patients (seven males) were diagnosed with ARVC. Mean age at clinical presentation was 42.6+/-14.8 years. Two patients (18.1%) had positive family history of ARVC or premature sudden cardiac death. The commonest presenting symptoms were palpitation (73%) and dizziness (46%). Spontaneous ventricular tachycardia (VT) was the presenting arrhythmia in 54% and 1 (9%) with ventricular fibrillation and cardiac arrest. Seven patients (64%) had the ECG abnormality as defined by the Task Force. Echocardiography showed right ventricular (RV) dilatation in five patients (46%) and all patients had normal left ventricular function. Nine patients (90%) had RV wall thinning or fibrofatty replacement on MRI examination. Inducible monomorphic VT was detected in four out of nine patients at EPS. All eight patients had normal coronary arteries and left ventriculogram but RV dilatation and global hypokinesia was seen in three patients. Implantable cardioverter defibrillators were implanted in five patients and two of them had shocks delivered during the follow-up period. CONCLUSION: In this study, familial incidence of premature sudden death in patients with ARVC appears to be low and left ventricular involvement in affected individuals is uncommon. MRI is still the best investigation for ARVC.     

Right ventricular dysfunction in chronic heart failure patients

AIM: To evaluate any differences in haemodynamic and echocardiographic parameters in patients with both left (LV) and right ventricular (RV) systolic dysfunction and in patients with isolated LV systolic dysfunction. STUDY GROUP: One hundred patients with RV systolic dysfunction defined as peak velocity of tricuspid annular motion in systole (Sa)<11.5 cm/s, and 55 patients without RV systolic dysfunction Sa>11.5 cm/s. All patients had LV systolic dysfunction, LV ejection fraction (EF) below 40%, NYHA II-IV. METHODS: LV diameters, volumes and EF were measured by echocardiography. Patients underwent tissue Doppler imaging (TDI) of tricuspid annular motion with measurement of peak systolic velocity (Sa), peak early (Ea) and peak late (Aa) diastolic velocities. Right heart catheterization was also performed. RESULTS: Patients with RV systolic dysfunction did not differ from those without RV systolic dysfunction in terms of LV function. Patients with RV systolic dysfunction had larger RV dimension 30.6+/-5.8 vs. 33.9+/-6.7 mm, p<0.002. The patients with RV systolic dysfunction had higher values on right heart catheterization: MPAP 29.6+/-12.1 vs. 24.9+/-11.4 mm Hg, p<0.02, PCWP 20.8+/-10.0 vs. 17.3+/-9.3 mm Hg, p<0.03, PVR 189.9+/-123.3 vs. 137.7+/-94.9 dyn s cm(-5), p<0.008, CVP 7.7+/-5.6 vs. 5.1+/-3.9 mm Hg, p<0.002. The patients with RV systolic dysfunction had more pronounced diastolic dysfunction measured by TDI: Ea 9.9+/-2.3 vs. 11.4+/-2.5 cm/s, p<0.0001 and Aa 13.1+/-4.0 vs. 16.5+/-4.7 cm/s, p<0.000007. CONCLUSION: Patients with heart failure and both left and right ventricular systolic dysfunction showed more serious findings on central haemodynamics as well as more pronounced right ventricular diastolic dysfunction than those with isolated left ventricular systolic dysfunction.     

Arrhythmogenic right ventricular cardiomyopathy in two pairs of monozygotic twins

Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inheritant disease with an autosomal dominant mode of transmission with incomplete penetrance and variable expression. Linkage analysis in affected families succeeds in identifying 9 loci determining 9 subtypes of the disease. Genotype phenotype correlation is unclear and the influence of various environmental factors is discussed. OBJECTIVES: Genotype phenotype correlation in 2 pairs of monozygotic twins with ARVC and the role of environmental factors are analyzed. PATIENTS AND METHODS: Among 40 pts with ARVC and their 195 relatives there were 2 pairs of monozygotic twins: brothers, age 47 y; and sisters, age 48 y. History, ECG, Holter monitoring, 2D and Doppler Echo, and MRI were analyzed. RESULTS: Twin brothers: ARVC was diagnosed in the proband after the episode of VT with LBBB morphology (enlarged right ventricle, focal hypokinesia of apex, MR evidence of adipose tissue in RV wall). Identical morphology of RV was seen in asymptomatic twin brother. The patient presenting arrhythmia has been rowing for 4 years. Twin sisters: diagnosis was done during family screening. Both were asymptomatic. RV morphology typical for ARVC was found discrete in one of them (bulges adipose tissue in the RV apex); the latter showed changes suggesting RV abnormality (mild segmental dilatation of infundibulum, adipose tissue in a free wall of the RV). No differences in previous viral infections and sports involvement were observed. CONCLUSIONS: 1. Clinical picture of ARVC in monozygotic twins is not identical. 2. Strenuous effort may be a factor triggering the arrhythmia in pts with ARVC.     

Chronic recurrent right ventricular tachycardia in patients without ischemic heart disease: Clinical,hemodynamic, and angiographic findings

Surgical cure of right ventricular tachycardia (RVT) has been recently described in patients with “arrhythmogenic right ventricular dysplasia,” a disease characterized by abnormal electrical activation of the right ventricle and localized or generalized angiographic right ventricular (RV) wall motion abnormalities (WMA). In search of a selective RV cardiomyopathy complicated by chronic recurrent RVT, 38 consecutive patients (mean age 30.5 ± 12 years) with RVT and no ischemic heart disease were studied clinically, noninvasively, and by cardiac catheterization including left and right ventriculography. RV volumes were as follow: end-systolic volume ranged from 23 to 103 (mean ± SD, 45.8 ± 20) cc/m² and was abnormal in 14 patients (37%); end-diastolic volume ranged from 57 to 138 (90.5 ± 26) cc/m² and was abnormal in 15 patients (39%); ejection fraction (EF) ranged from 0.18 to 0.64 and was decreased in five patients (13%). Seventeen patients (45%) had abnormal RV volume, EF, and/or pressures (RVD), five (13%) of whom had abnormal LV volume, EF, and/or pressures (LVD), and 12 (32%) patients with RVD had no LVD. Twenty-one patients (55%) had no RVD, two of whom had LVD. Only two of the 17 patients had RV regional WMA, one with and one without LVD. Most patients with LVD five of seven (71%) also had RVD while 12 of 31 patients (39%) with no LVD had RVD. In conclusion, less than one half of patients with RVT had selective RV cardiomyopathy and more than one half of patients with RVT had normal RV hemodynamics and angiography.     

Correlation between the Parameters of Signal‐Averaged ECG and Two‐Dimensional Echocardiography in Patients with Arrhythmogenic Right Ventricular Cardiomyopathy

Background: The correlation between parameters of two‐dimensional echocardiography and signal‐averaged ECG (SAECG) in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) is not known well. Methods: Thirty‐three patients (13 females, 40.3 ± 14.4 years old) were included in this study. Both the right and left ventricular dimensions and systolic function were assessed with two‐dimensional echocardiography. The SAECG was performed with high‐gain amplification and filtered using bidirectional Butterworth filters between 40 and 250 Hz. We evaluated the correlation between the parameters of the SAECG and two‐dimensional echocardiography. Results: The right ventricular (RV) outflow tract was the most frequently (n = 18, 54%) involved segment. Six (18%) patients had only mildly decreased RV systolic function. All the other patients had normal RV systolic function. Although localized left ventricular wall motion abnormalities were observed in 14 (42%) patients, the left ventricular ejection fraction was normal in most (n = 32, 97%). Late potentials were positive in 22 (63%) patients. There was no significant correlation between parameters of the SAECG and two‐dimensional echocardiography for the entire patient population. Conclusions: The SAECG parameters exhibited no correlation to any of two‐dimensional echocardiography parameters in the patients with ARVC. Fragmented electrical activity may develop with no significant relation to the anatomical changes in the patients with ARVC.     

Right ventricular systolic function and the manner of transformation of the right ventricle in patients with dilated cardiomyopathy.

BACKGROUND: Dilated cardiomyopathy (DCM) is generally considered to be accompanied by both left and right ventricular dysfunction, but most studies only analyze the left ventricular function. METHODS AND RESULTS: Biplane right ventriculography was performed in 13 control subjects and 13 patients with DCM and New York Heart Association functional class II. Three dimensions of the right ventricle (RV) (the long axis dimension (LA), the anterior - posterior dimension (AP), and the septum -free wall dimension (SF)) and 2 dimensions of the left ventricle (LV) (LA and AP) were examined to assess regional function. The group with DCM had a lower stroke volume index and RV ejection fraction. In the RV dimensional analysis, the group with DCM had a smaller SF and a larger AP at end-diastole, and larger AP and LA at end-systole. There was a significant linear negative correlation between SF of RV and AP of LV at end-diastole. CONCLUSION: In clinically well-controlled cases of DCM, RV systolic function is depressed, and the RV is compressed by the LV, becoming less thick than in the controls. This transformation results from some parallel interaction between the RV and a markedly enlarged LV.     

Right ventricular infarction: two-dimensional echocardiographic evaluation

Seventeen patients with predominant right ventricular infarction (RVMI) were studied with two-dimensional echocardiography (2DE). On initial 2DE all had abnormal wall motion (AWM), defined as akinesis plus dyskinesis, in the inferior right ventricle (RV), inferior interventricular septum, and inferior left ventricle (LV). The extent of RV vs LV AWM in short-axis sections at mitral, chordal, and papillary levels was 58% vs 29%, 56% vs 38%, and 59% vs 38%, respectively. The calculated topographic extent of AWM was greater in the RV than in the LV (58% vs 36%, p less than 0.05), and the RV/LV ratio (1.65) exceeded (p less than 0.001) unity. Peak creatine phosphokinase levels correlated significantly (p less than 0.001) with the topographic extent of LV AWM (r = 0.79) or RV + LV AWM (r = 0.75). Although all patients had RV dilatation, eight also had LV dilatation. Serial studies detected the cause of mechanical complications (n = 13), mural echo densities suggesting thrombi (LV in six and RV in seven), and persistent AWM in survivors. Thus, 2DE provided diagnostic data, and assessment of RV and LV AWM confirmed predominant RV involvement.     

MR Imaging of arrhythmogenic right ventricular cardiomyopathy: morphologic findings and interobserver reliability

BACKGROUND: Magnetic resonance (MR) imaging is frequently used to diagnose arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D). However, the reliability of various MR imaging features for diagnosing ARVC/D is unknown. The purpose of this study was to determine which morphologic MR imaging features have the greatest interobserver reliability for diagnosing ARVC/D. METHODS: Forty-five sets of films of cardiac MR images were sent to 8 radiologists and 5 cardiologists with experience in this field. There were 7 cases of definite ARVC/D as defined by the Task Force criteria. Six cases were controls. The remaining 32 cases had MR imaging because of clinical suspicion of ARVC/D. Readers evaluated the images for the presence of (a) right ventricle (RV) enlargement, (b) RV abnormal morphology, (c) left ventricle enlargement, (d) presence of high T(1) signal (fat) in the myocardium, and (e) location of high T(1) signal (fat) on a Likert scale with formatted responses. RESULTS: Readers indicated that the Task Force ARVC/D cases had significantly more (chi(2) = 119.93, d.f. = 10, p < 0.0001) RV chamber size enlargement (58%) than either the suspected ARVC/D (12%) or no ARVC/D (14%) cases. When readers reported the RV chamber size as enlarged they were significantly more likely to report the case as ARVC/D present (chi(2)(= )33.98, d.f. = 1, p < 0.0001). When readers reported the morphology as abnormal they were more likely to diagnose the case as ARVC/D present (chi(2) = 78.4, d.f. = 1, p < 0.0001), and the Task Force ARVC/D (47%) cases received significantly more abnormal reports than either suspected ARVC/D (20%) or non-ARVC/D (15%) cases. There was no significant difference between patient groups in the reported presence of high signal intensity (fat) in the RV (chi(2) = 0.9, d.f. = 2, p > 0.05). CONCLUSIONS: Reviewers found that the size and shape of abnormalities in the RV are key MR imaging discriminates of ARVD. Subsequent protocol development and multicenter trials need to address these parameters. Essential steps in improving accuracy and reducing variability include a standardized acquisition protocol and standardized analysis with dynamic cine review of regional RV function and quantification of RV and left ventricle volumes.     

Desmoglein-2 mutations in arrhythmogenic right ventricular cardiomyopathy: a genotype-phenotype characterization of familial disease.

AIMS: Mutations in the desmoglein-2 (DSG2) gene have been reported in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) but clinical information regarding the associated phenotype is at present limited. In this study, we aimed to clinically characterize probands and family members carrying a DSG2 mutation. METHODS AND RESULTS: We investigated 86 Caucasian ARVC patients for mutations in DSG2 by direct sequencing and detected eight novel mutations in nine probands. Clinical evaluation of family members with DSG2 mutations demonstrated penetrance of 58% using Task Force criteria, or 75% using proposed modified criteria. Morphological abnormalities of the right ventricle were evident in 66% of gene carriers, left ventricular (LV) involvement in 25%, and classical right precordial T-wave inversion only in 26%. Sustained ventricular arrhythmia was present in 8% and a family history of sudden death/aborted sudden death in 66%. CONCLUSION: Mutations in DSG2 display a high degree of penetrance. Disease expression was of variable severity with LV involvement a prominent feature. The low prevalence of classical ECG changes highlights the need to expand current diagnostic criteria to take account of LV disease, childhood disease expression, and incomplete penetrance.