A case of arrhythmogenic right ventricular dysplasia with ventricular fibrillation

A case of repeated attacks of ventricular fibrillation is described. The patient suffered from an arrhythmogenic right ventricular dysplasia (ARVD) documented by right and left ventriculograms and myocardial biopsies obtained during surgical treatment of the arrhythmia. The histological changes were interpreted as being signs of fresh myocardial damage of unknown origin in addition to a replacement of the normal myocardium by adipose and fibrotic tissue. The repeated attacks of ventricular fibrillation in this patient contrast to the arrhythmia spectrum noted in the available literature on ARVD, mostly stable chronic ventricular tachycardias.     

An abnormal right ventricular apical angle is indicative of global right ventricular impairment

The presence of right ventricular (RV) dysfunction is an adverse prognostic indicator but current echocardiographic methods have some limitations. RV apical angles in systole and diastole were correlated with known parameters of RV function in patients without pulmonary hypertension (Group 1) and in patients with pulmonary hypertension (Group 2). RV apical angles were significantly smaller in both systole (22 +/- 7 degrees) and diastole (33 +/- 6 degrees) in Group 1 patients when compared to Group 2 (54 +/- 18 degrees, p < 0.0001 and 59 +/- 17 degrees, p < 0.0001, respectively). RV apical angles, both in systole and diastole, were strongly correlated with RV end-systolic area (R = 0.89, p < 0.0001) and end-diastolic area (R = 0.81, p < 0.0001), respectively. Similarly, the apical systolic and diastolic angle correlated well with decreased tricuspid annular plane systolic excursion (TAPSE, R = -0.76 and R = -0.73, p < 0.001) as well as with decreased RV fractional area change (R = -0.81 and R = -0.77, p < 0.001). Therefore, we conclude that this new measurement of RV apical angle is simple and useful to quantify RV apical structural and functional abnormalities that are well correlated with global RV impairment in patients with chronic pulmonary hypertension.     

组织多普勒成像对慢性肺动脉高压患者右心室功能的评价

目的 探讨组织多普勒成像技术评价慢性肺动脉高压患者右心室功能及与肺动脉收缩压的关系.方法 对2006年10月至2007年3月在复旦大学华山医院心内科就诊的35例慢性肺动脉高压和35名正常人进行组织多普勒超声心动图检查,从心尖四腔观获得右室侧壁三尖瓣环的运动速度频谱图,测量收缩期S波峰速度(Sm),舒张早期负向E波峰速度(Em),舒张晚期负向A波峰速度(Am),等容收缩时间(IVCT)和等容舒张时间(IVRT).结果 肺动脉高压组Sm、Em和Em/Am均低于对照组,肺动脉高压组Am、IVRT均高于对照组,差异均有显著性意义.IVRT和肺动脉收缩压(PASP)存在显著的正相关(r=0.78,P＜0.01),IVRT≥60 ms诊断肺动脉高压的敏感度和特异度分别为83%和86%.结论 慢性肺动脉高压导致右心收缩及舒张功能减退,当连续多普勒不能估测肺动脉收缩压时,组织多普勒可作为肺动脉收缩压估测的新方法.     

Comparison of left and right ventricular function in acute myocardial infarction

Pulmonary arterial end-diastolic and mean right atrial pressures were compared in 25 patients with acute myocardial infarction and in one patient with unstable angina. No consistent relationship was observed between these pressures. Simultaneous ventricular function curves relating the stroke work of each ventricle to its respective filling pressure were constructed on 34 occasions, dextran infusion or diuresis being used to alter the filling pressure. The curves from each ventricle were described mathematically by a quadratic (parabolic) function as well as by a straight line function and then compared by canonical correlation analysis. Alterations in the left ventricular function curves occurred with and without depression of right ventricular function curves. These hemodynamic measurements demonstrate that acute myocardial infarction can alter the relationship between left and right ventricular function.     

Catheter ablation of ventricular tachycardia in arrhythmogenic right ventricular dysplasia

Arrhythmogenic right ventricular dysplasia (ARVD) is a progressive, genetically determined fibro-fatty infiltrative myocardial disease with an estimated prevalence in the general population to be 1:5,000 to 1:10,000. ARVD leads to electrical instability that may predispose to life-threatening ventricular arrhythmia, heart failure, and sudden death. We reviewed the pathological substrate for ventricular arrhythmias, ECG findings and treatment modalities in ARVD. Importantly, novel techniques such as electroanatomic and voltage mapping has greatly improved the identification of the scared substrate in the settings of ARVD and have improved safety and efficacy of VT ablation procedures associated with this entity.     

Arrhythmogenic right ventricular dysplasia presenting as right ventricular outflow tract tachycardia.

A case of a 51-year old male is presented. A left bundle branch block inferior axis tachycardia was manifest. At electrophysiological study this tachycardia was inducible and was ablated in the septal right ventricular outflow tract (RVOT). Two other tachycardias were identified both with right bundle branch block (RBBB) morphology raising the suspicion of diffuse pathology. Arrythmogenic right ventricular dysplasia (ARVD) was confirmed by right ventricular angiography and magnetic resonance imaging (MRI). An implantable cardioverter defibrillator (ICD) was implanted and an appropriate shock was later delivered.     

Quantitative analysis of the signal-averaged QRS in patients with arrhythmogenic right ventricular dysplasia

Temporal signal averaging of the surface QRS (VI + V3 + V5)was performed in 16 patients with arrhythmogenic right ventriculardysplasia and in 16 normal subjects. The differences betweenARVD patients and normals were large for the filtered QRS duration(FQRSd) (146.2±18.9 vs. 91.8±4.1ms, P<000001),the late potential duration (LPd) (83.5±23.3 ms vs. 23.6±4.6ms,P< 0.00001), the LPd/ FQRSd ratio (53.9± 10.1% vs.25.8±5.1%, P <0.00001), the filtered QRS amplitude(234.0±61.1µV vs. 429±942 fiV, P <0001),and the root mean square voltage of the signals in the terminal40 and 50 ms of the FQRS (RMS40 and RMS50) (18.4± 10.0µVvs. 118.4±49.8p.V, P<0.0005 and 27.9± 19.2µVvs. 217.0±66.3fiV, P<0000002). RMS50 <40µVdiscriminated best between ARVD and normals (81% sensitivityand 100% specificity). The right-sided predominance of the abnormalitiesin ARVD was demonstrated by the significantly longer FQRSd andLPd, and the higher ratio LPd/FQRSd in right than in left precordialleads. The arrhythmia susceptibility did not seem to influencethe presence of or properties ofLP in the ARVD group. Patientswith multiple QRS morphologies during ventricular tachycardia(VT) had, compared with patients with only one type of VT, longerLPd (108.3 ±46.4 ms vs. 64.2 ±31.7 ms, P<0.02)and lower RMS40 voltage (9.4±9.9 µV vs. 25.4±21.6µV, P<0.05). The relative heart volume was positivelycorrelated with delayed activity, but an enlarged heart wasnot apre-requisitefor the presence ofLP. The method thus identifieschanges which are specific to ARVD. The findings indicate thatcertain electrical or morphological conditions are requiredfor the occurrence of arrhythmias.     

Long term results of cardioverter-defibrillator implantation in patients with right ventricular dysplasia and malignant ventricular tachyarrhythmias

OBJECTIVE—To study the outcome of patients with arrhythmogenic right ventricular dysplasia treated with an implantable cardioverter-defibrillator (ICD) for ventricular tachyarrhythmias complicated by haemodynamic collapse.
DESIGN—Observational study.
SETTING—University hospital.
PATIENTS—Nine consecutive patients (eight male, one female; mean (SD) age, 36 (18) years) with arrhythmogenic right ventricular dysplasia presenting with ventricular tachycardia and haemodynamic collapse (n = 6) or ventricular fibrillation (n = 3), treated with an ICD.
MAIN OUTCOME MEASURES—Survival; numbers of and reasons for appropriate and inappropriate ICD interventions.
RESULTS—After a mean (SD) follow up of 32 (24) months, all patients were alive. Six patients received a median of 19 (range 2-306) appropriate ICD interventions for events detected in the ventricular tachycardia window; four received a median of 2 (range 1-19) appropriate ICD interventions for events detected in the ventricular fibrillation window. Inappropriate interventions were seen for sinus tachycardia (18 episodes in three patients), atrial fibrillation (three episodes in one patient), and for non-sustained polymorphic ventricular tachycardia (one episode in one patient).
CONCLUSIONS—Patients with arrhythmogenic right ventricular dysplasia and malignant ventricular arrhythmias have a high recurrence rate requiring appropriate ICD interventions, but they also often have inappropriate interventions. Programming the device is difficult because this population develops supraventricular and ventricular tachyarrhythmias with similar rates.


Keywords: arrhythmogenic right ventricular dysplasia; implantable cardioverter defibrillator; arrhythmia     

Catheter ablation of stable and unstable ventricular tachycardias in patients with arrhythmogenic right ventricular dysplasia

INTRODUCTION: A reentrant circuit within an area of abnormal myocardium is suspected as the origin of ventricular tachycardia (VT) in patients with arrhythmogenic right ventricular dysplasia (ARVD). OBJECTIVES: To examine the relationship between the reentrant circuits of VT and the abnormal electrograms in ARVD, and to assess the feasibility of a block line formation in the reentrant circuit isthmus utilizing electroanatomical mapping system (CARTO) guidance. METHODS AND RESULTS: An electrophysiological study and catheter ablation (CA) were performed in 17 ARVD patients (13 men, 47 +/- 17 year) using CARTO. Endocardial mapping during sinus rhythm demonstrated electrogram abnormalities extended from the tricuspid annulus (TA) or the right ventricular outflow tract in 16 of 17 patients. In 13 hemodynamically stable VTs, the reentrant circuits and critical slow conduction sites for the CA were investigated during VTs. The entire macro-reentrant pathway was identified in 6/13 stable VTs (figure-of-8 in 4, single loop in 2). In the remaining seven VTs, a focal activation pattern was found in four and an unidentifiable pattern in three. CA successfully abolished all the macro-reentrant and focal tachycardias, however, not effective in three unidentifiable VTs. In the 13 cases with unstable VT, the linear conduction block zone was produced between the sites with abnormal electrograms and the TA. Ultimately, 23/26 VTs (88%) became noninducible after the CA. During follow-up (26 +/- 15 months), 13/17 patients remained free from any VT episodes. CONCLUSIONS: CARTO is useful for characterizing the anatomical and electrophysiological substrates, and for identifying the optimal ablation sites for VT associated with ARVD.     

A casual spontaneous mutation as possible cause of the familial form of arrhythmogenic right ventricular cardiomyopathy (arrhythmogenic right ventricular dysplasia).

In a family affected by arrhythmogenic right ventricular cardiomyopathy (ARVC) the familial occurrence was investigated. All 14 members of two generations were investigated carefully, and only 2 (father and one son) members were affected. Both subjects had a massive form of the disease with relevant ventricular arrhythmias. Apart from the limitations of having investigated few subjects, this behavior suggests a genetic mutation appearing in the father and transmitted via an autosomal dominant trait.     

Utility of right ventricular tissue Doppler imaging: correlation with right heart catheterization

Objectives: The objective of this study was to correlate tissue Doppler imaging of the right ventricle (RV) with pulmonary hemodynamics in patients referred for right heart catheterization. Methods: Seventy subjects (mean age 54 ± 13; 35 males) prospectively underwent tissue Doppler imaging of the RV and right heart catheterization within 1 day of each other. Peak systolic velocity and strain were measured at the RV free wall and correlated with pulmonary hemodynamics. Results: RV myocardial velocity demonstrated no correlation with any hemodynamic variable. While RV strain demonstrated significant correlation with cardiac index (r =−0.61; P < 0.001), correlations with transpulmonary gradient (r = 0.26; P < 0.05) and pulmonary vascular resistance (r = 0.30; P < 0.05) were weaker. Subgroup analysis revealed that in patients with left ventricular systolic dysfunction (n = 31), RV strain showed no correlation with any hemodynamic variable. In patients with normal left ventricular systolic function (n = 39), correlations were significant between RV strain and mean pulmonary artery pressure (r = 0.59; P < 0.001), pulmonary vascular resistance (r = 0.60; P < 0.001), and cardiac index (r =−0.67; P < 0.001). Conclusions: RV myocardial strain correlates significantly with pulmonary hemodynamics in patients with pulmonary hypertension and normal left ventricular function. However, there is no correlation with RV performance in patients with left ventricular dysfunction.     

Noninvasive recognition of the parchment right ventricle (Uhl's anomaly arrhythmogenic right ventricular dysplasia) syndrome

The case of a 53-year-old man with right heart failure, selective enlargement of the right-sided cardiac chambers, and recurrent sustained ventricular tachycardia is presented. Echocardiographic, radionuclide ventriculographic, and angiographic studies were typical of the right ventricular abnormalities in Uhl's anomaly; electrocardiographic and electrophysiologic findings were those of arrhythmogenic right ventricular dysplasia. Features of this unusual cause of cardiac failure and ventricular arrhythmias in the adult are reviewed, and compared to previous reports of both Uhl's anomaly and arrhythmogenic right ventricular dysplasia. We postulate that these two syndromes are manifestations of a single, presumably congenital, pathophysiologic process—the “parchment right ventricle” syndrome.     

Multiple exercise induced syncopal episodes in a young woman due to arrhythmogenic right ventricular dysplasia.

A case of a young woman with multiple exercise induced syncopal episodes due to arrhythmogenic right ventricular dysplasia is described. The report emphasizes the importance of exercise induced syncope and the management is described.