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Unlabelled: We searched for special features in patients with complete and incomplete right bundle branch block diagnosed as having arrhythmogenic right ventricular cardiomyopathy/dysplasia. Whether right bundle branch block is a frequent finding in arrhythmogenic right ventricular cardiomyopathy should be studied. The question is whether special features exist such as T-wave inversions, localized right precordial QRS prolongation and r'/s ratio<1., Results: ARVC could be diagnosed according to ISFC/ESC criteria in 374 patients. CRBBB was found in 22 cases (6%) and iCRBBB was present in 47 cases (12.5%). In CRBBB T wave inversions ≥ V4 was found in 10 cases (n.s.) and r'/s ratio<1 was present in 12 cases (p<0.001). In iCRBBB T wave inversions ≥ V4 was found in 10 cases (n.s.) and ST segment elevation in right precordial leads was present in 19 cases (p<0.005). In all patients with ARVC localized right precordial QRS prolongation was found. Patients with CRBBB have a bad prognosis: 17 of 22 patients developed biventricular heart failure requiring heart transplantation and diuretic therapy., Conclusions: CRBBB and iCRBBB are infrequent findings in arrhythmogenic right ventricular cardiomyopathy. Complete right bundle branch block is characterized by r'/s ratio<1. There are no significant T wave inversions ≥ V4. Incomplete right bundle branch block is characterized by ST segment elevation in right precordial leads but not by T wave inversions ≥ V4., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Latest advances in the diagnostic management of arrhythmogenic right ventricular dysplasia-cardiomyopathy (ARVD/C) confirm that ARVD/C is not a rare disease (one affected in 1000-1250 inhabitants) and is of familial origin in 50-80% of cases. Diagnostic criteria defined in 1994 lead to low rates in the diagnosis of ARVD/C. Progress was made in the definition of diagnostic markers. New criteria of localised right precordial QRS prolongation could be identified. The detection of epsilon potentials could be enhanced by highly amplified and modified recording techniques. Vectorcardiography, signal averaging per lead and electroanatomic voltage mapping might become more important in the future. Cardiac MRI does not represent the single diagnostic test to make the diagnosis of ARVD/C. It remains a promising noninvasive imaging technique with advantages in the evaluation of the right ventricle. After the characterisation of mutations in the plakophilin-2 gene, molecular genetics is going to become an important diagnostic tool. Up to now, unsolved problems exist in the differentiation of ARVD/C and other conditions with ventricular arrhythmias evolving from the right ventricle such as Brugada syndrome and right ventricular outflow tract tachycardia. These problems can be overcome by distinct ECG analysis and the use of imaging techniques. With the help of corrected and modified diagnostic criteria it seems to be possible to identify symptomatic and asymptomatic affected by ARVD/C with predominantly major criteria and only in a minority of cases minor criteria.

Syncopes appear in 10-20% in arrhythmogenic right ventricular dysplasia-cardiomyopathy (ARVD/C). In the majority of cases sustained or non-sustained monomorphic ventricular tachycardias represent the underlying mechanism of syncope. In other cases the mechanism remains unclear. In 37 patients (23 females, mean age 43.6+/-12.8 years) without detectable and inducible monomorphic ventricular tachycardia, a diagnostic algorithm including repeat ECG, holter monitoring, telemetry, electrophysiological examination, ajmaline challenge, tilt table testing and neurological work-up (EEG, cranial computer tomography) was used in order to identify the mechanism of syncopes. Constant AV block 3 degrees could be found in 3 patients (2 males). Intermittant AV block 2 degrees or 3 degrees could be identified in 3 females. Four males had abnormal Wenckebach point during rapid atrial stimulation, 3 males demonstrate isolated HV interval prolongation. Rapid polymorphic VT and VF could be induced in a young female with ARVD/C. Eight patients (7 females) presented with recurrent syncopes and provocable right precordial ST elevation and right bundle branch block during ajmaline challenge. Three patients had abnormal tilt table testing as the only pathological finding. In one female with intermittent AV block 2 degrees tilt table testing and ajmaline challenge was positive. One female had the diagnosis of focal epilepsia after neurological work-up. In 11 cases the mechanism of syncopes remained unclear. In patients with ARVD/C and syncopes beyond detectable or inducible monomorphic VT, several mechanisms of syncopes could be identified with conduction disease as the predominant finding. These results may help in identifying rare mechanisms of syncopes in ARVD/C.

In a cardiological department of a non-referral hospital responsible for 80,000 inhabitants with 2500 in-hospital patients and 1500 out-hospital patients per year, the prevalence, symptoms and prognosis of arrhythmogenic right ventricular dysplasia-cardiomyopathy (ARVD/C) were examined retrospectively. From 1997 to 2002, ARVD/C was diagnosed in 35 females and 45 males (overall prevalence 1 in 1000 inhabitants) with a mean age of 45.6 years. Symptoms were chest pain (80%), palpitations (60%) and syncopes (30%), and clinical findings were repetitive ventricular premature beats (50%), supraventricular arrhythmias (30%), ventricular tachycardia (20%), aborted sudden death due to ventricular fibrillation (1%), right heart failure (4%), biventricular heart failure (1%) and high grade AV nodal block (4%). Endomyocardial biopsies were not performed. Aborted sudden death occurred in only one patient (0.3%) before the diagnosis was made, annual heart failure rate was 1%. No deaths appeared in a follow-up of 1-5 (mean 2.4) years with clinical assessment as the basis of diagnosis. The prevalence of ARVD/C is much higher and the prognosis better than expected from results of reference centers.

An association between arrhythmogenic right ventricular dysplasia-cardiomyopathy (ARVD/C) and Brugada syndrome can be supposed according to several case reports. In order to examine a possible link between ARVD/C and Brugada syndrome, systematic ajmaline testing with 1 mg/kg body weight intravenously, was done in 55 patients (32 males, mean age 46.7+/-12.3 years) with ISFC/ESC criteria of ARVD/C. In nine patients ajmaline testing could demonstrate coved ST segment elevation of at least 2 mm in at least two right precordial leads. Three of these patients had recurrent syncopes. Electrophysiological study revealed non-sustained ventricular tachycardia with left bundle branch block configuration and inferior axis in only one case. Systematic ajmaline testing could demonstrate a definite link between ARVD/C and Brugada syndrome.

The value of imaging techniques such as transthoracic echocardiography, angiography and magnetic resonance imaging in the diagnosis of arrhythmogenic right ventricular dysplasia-cardiomyopathy (ARVD) is limited. First experiences with intracardiac ultrasound have been made during electrophysiological interventions. The ability of using intracardiac ultrasound in ARVD should be tested. In 25 patients with IFSC/ESC criteria of ARVD (nine males, 16 females) with a mean age of 54 (29-78) years suffering from sustained ventricular tachycardia in three cases, positive family history in four cases and syncopes in six cases intracardiac ultrasound was done using 6 French (Fr) 12.5 MHz catheters and the CLEAR VIEW ULTRA Intravascular System (Boston Scientific). Images were taken from the right ventricular apex, outflow tract and infundibulum. Results were compared to selective right ventricular angiography. Right ventricular (RV) angiography revealed bulges and a partial or complete loss of trabecular structure in 22 cases at the apex, in 13 cases at the infundibulum and in 14 cases at the right ventricular outflow tract. Intracardiac echocardiography was able to demonstrate sacculations in all patients at the apex, in 20 cases at the infundibulum and in 16 patients at the right ventricular outflow tract. Sacculations in all segments of the right ventricle were based on a partial or complete loss of trabecular structure. A whole of 36 segments presented with wall thinning (<3 mm) and 15 segments with normal wall structure and wall thickening of surrounding myocardium (>4 mm). In 26 segments the structure of right ventricular wall was inhomogeneous. In comparison to angiography as the 'gold standard' intracardiac ultrasound presented with additional details in 12 cases and the demonstration of angiographic misinterpretation in one case. Intracardiac ultrasound in ARVD is feasible in all cases with 6 Fr 12.5 MHz catheters and provides additional information to the angiographic phenomenon of bulges and to the aspect of tissue characterisation.