Contrast echocardiography for perfusion in right ventricular cardiomyopathy.

Right ventricular (RV) cardiomyopathy is a familiar myocardial disease of RV characterized by extensive fatty replacement of the myocardium. Conventional echocardiography is able to show abnormalities in myocardial contractility, but fat on the images appears to be similar to the surrounding tissue or fluid. The present case suggests the clinical role of contrast echocardiography showing perfusion abnormalities in patients with RV cardiomyopathy in the region of the fat depositions.     

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)     

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.     

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     

Arrhythmogenic Right Ventricular Dysplasia: Clinical Results with Implantable Cardioverter Defibrillators

Arrhythmogenic right ventricular dysplasia is a clinical entitycharacterized by fatty infiltration of the right ventricle and left bundlemorphology ventricular tachycardia occurring in young patients. The mostcommon cause of death is tachyarrhythmic. Pharmacological andnonpharmacological therapies, including implantable cardioverterdefibrillators, have been used to treat the arrhythmias. However, rightventricular endocardial leads in this population may be associated with anincreased risk of perforation and suboptimal sensing and defibrillationefficacy due to the diseased right ventricle. We report on 12 patients witharrhythmogenic right ventricular dysplasia who were treated with implantablecardioverter defibrillators. The mean age was 31± 9 years (range15-48). Patients presented with presyncope (5), syncope (4), or cardiacarrest (3). All patients had electrocardiographic abnormalitiescharacteristic of the condition.Follow-up averaged 22 ± 13months (range 1-45). There was one sudden death at 1 month of follow-up. Ofthe 12 patients, 8 have had appropriate therapy delivered by the implantabledefibrillator. Six patients are currently on sotalol to reduce the frequencyof implantable defibrillator discharges. In conclusion, implantablecardioverter defibrillators with nonthoracotomy leads are feasible and safein patients with arrhythmogenic right ventricular dysplasia. The frequencyof appropriate therapy is high, supporting the use of implantablecardioverter defibrillators in this population.During programmedelectrical stimulation nine patients had sustained ventricular tachycardia,while three patients had no inducible arrhythmia. Transvenous leads wereplaced in nine patients. In these patients pacing thresholds weresignificantly higher, R-wave amplitudes were significantly lower, anddefibrillation thresholds were not significantly different than in a cohortof patients without right ventricular dysplasia. There were no acute orchronic complications of right ventricular lead placement.     

Long-term follow-up in patients with arrhythmogenic right ventricular cardiomyopathy

Long‐Term Prognosis in Patients with ARVC. Introduction: Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a major cause of sudden cardiac death due to tachyarrhythmias. The purpose of this study was to investigate the long‐term prognosis in patients with ARVC and the incidence of rapid ventricular arrhythmias during follow‐up. Methods: Thirty ARVC patients (19 male, 63.3%, mean age 48 ± 15 years) fulfilling modified Task Force criteria 2010 were included. Of them, 13 patients (43.3%) received implantable cardioverter‐defibrillator (ICD) implantation. Rapid ventricular arrhythmia was defined as electrical storm or the occurrence of ventricular tachycardia (VT) or ventricular fibrillation (VF) with a cycle length of 240 ms or less that necessitate shock delivery to 2 or more times within a 24‐hour period. Results: With a mean follow‐up of 68 ± 10 months, 6 patients (20%) with ICD implantation had recurrent rapid VT/VF. One (3.3%) of them died of multiple shocks and SCD, and 5 (16.7%) had multiple ICD therapies due to VT/VF and electrical storm. The interval between the diagnosis of ARVC and occurrence of rapid VT/VF was 13.4 ± 4.9 months. Most (5/6, 83.3%) events of recurrent rapid VT/VF occurred within 2 years. Ablated patients who did not receive an ICD implant were totally free of rapid VT/VF. Conclusions: For patients with ARVC, long‐term prognosis is favorable. During a long‐term follow‐up, patients meeting the criteria for ICD implantation have a higher rate of rapid and potentially life‐threatening arrhythmias. However, early and clustered recurrence of rapid VT/VF in patients with an ICD is common, whereas late occurrence of rapid VT/VF is very rare. (J Cardiovasc Electrophysiol, Vol. 23, pp. 750‐756, July 2012)     

Newly diagnosed arrhythmogenic right ventricular dysplasia in an octogenarian

Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is thought to be a disease of the young, with the majority of newly diagnosed patients under 40 years of age. Establishing this diagnosis in elderly patients may be challenging, and a few reports exist of patients older than 70 years diagnosed with ARVD/C at autopsy. We report the case of an octogenarian with antemortem newly diagnosed ARVD/C. This case report represents the oldest patient to date to have a newly established diagnosis of ARVD/C and highlights the difficulty in making the diagnosis in the elderly.     

Arrhythmogenic ventricular cardiomyopathy:A paradigm shift from right to biventricular disease

Arrhythmogenic ventricular cardiomyopathy(AVC) isgenerally referred to as arrhythmogenic right ventricu-lar(RV) cardiomyopathy/dysplasia and constitutesan inherited cardiomyopathy.Affected patients maysuccumb to sudden cardiac death(SCD),ventriculartachyarrhythmias(VTA) and heart failure.Geneticstudies have identified causative mutations in genesencoding proteins of the intercalated disk that lead toreduced myocardial electro-mechanical stability.Theterm arrhythmogenic RV cardiomyopathy is somewhatmisleading as biventricular involvement or isolated leftventricular(LV) involvement may be present and thus abroader term such as AVC should be preferred.The di-agnosis is established on a point score basis accordingto the revised 2010 task force criteria utilizing imagingmodalities,demonstrating fibrous replacement throughbiopsy,electrocardiographic abnormalities,ventricu-lar arrhythmias and a positive family history includingidentification of genetic mutations.Although severarisk factors for SCD such as previous cardiac arrest,syncope,documented VTA,severe RV/LV dysfunctionand young age at manifestation have been identified,risk stratification still needs improvement,especially inasymptomatic family members.Particularly,the roleof genetic testing and environmental factors has to befurther elucidated.Therapeutic interventions include re-striction from physical exercise,beta-blockers,sotalol,amiodarone,implantable cardioverter-defibrillators andcatheter ablation.Life-long follow-up is warranted insymptomatic patients,but also asymptomatic carriersof pathogenic mutations.     

Use of implantable cardioverter defibrillators in patients with left ventricular assist devices

Patients with left ventricular assist devices (LVADs) are at high risk of sustained ventricular arrhythmias, but these may be remarkably well tolerated and the association with sudden death is unclear. Many patients who receive an LVAD already have an implantable cardioverter defibrillator (ICD). While it is standard practice to reactivate a previously implanted ICD in an LVAD recipient, this should include discussion of the revised risks and benefits of ICD therapy following LVAD implantation. In particular, patients should be warned that they might receive a significant number of ICD shocks that may not be life saving. When ICDs are reactivated, device programming should minimize the risk of repeated shocks for non-sustained or well-tolerated ventricular arrhythmias. Implantation of a primary prevention ICD after implantation of an LVAD is not supported by current evidence, poses potential risks, and should be the subject of a clinical trial before it becomes standard practice.     

Electroanatomic mapping characteristics of ventricular tachycardia in patients with arrhythmogenic right ventricular cardiomyopathy/dysplasia.

BACKGROUND: Ventricular tachycardia (VT) in arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVD) has been previously explored using entrainment mapping techniques but little is know about VT mechanisms and the characteristics of their circuits using an electroanatomical mapping system. METHODS AND RESULTS: Three-dimensional electroanatomical mapping was performed in 11 patients with well tolerated sustained VT and ARVD. Sinus rhythm mapping of the right ventricle was performed in eight patients showing areas of low bipolar electrogram voltage (<1.2 mV). In total 12 tachycardias (mean cycle length 382+/-62 ms) were induced and mapped. Complete maps demonstrated a reentry mechanism in eight VTs and a focal activation pattern in four VTs. The reentrant circuits were localized around the tricuspid annulus (five VTs), around the right ventricular outflow tract (one VT) and on the RV free lateral wall (two VTs). The critical isthmus of each peritricuspid circuit was bounded by the tricuspid annulus with a low voltage area close to it. The isthmus of tachycardia originating from the right ventricular outflow tract (RVOT) was delineated by the tricuspid annulus with a low voltage area localized on the posterior wall of the RVOT. Each right ventricular free wall circuit showed an isthmus delineated by two parallel lines of block. Focal tachycardias originated on the right ventricular free wall. Linear radiofrequency ablation performed across the critical isthmus was successful in seven of eight reentrant tachycardias. The focal VTs were successfully ablated in 50% of cases. During a follow-up of 9-50 months VT recurred in four of eight initially successfully ablated VTs. CONCLUSIONS: Peritricuspid ventricular reentry is a frequent mechanism of VT in patients with ARVD which can be identified by detailed 3D electroanatomical mapping. This novel form of mapping is valuable in identifying VT mechanisms and in guiding RF ablation in patients with ARVD.