RESUMO
BACKGROUND: Atrial fibrillation (AF) is the most common atrial arrhythmia in arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVD). Considering the histologic changes known in the right ventricular (RV) in ARVD, the aim of the present study was to examine right atrial (RA) pathology in patients with ARVD. METHODS: Histology of RA and RV was assessed from autopsy material in 3 patients with ARVD without persistent atrial arrhythmia. RA histology in 3 patients with permanent AF without ARVD and 5 patients without cardiovascular disease was also studied. Staining with hematoxylin phloxine saffron was performed for the ARVD patients to identify fibrosis, and hematoxylin-eosin for identification of lymphocytes. Masson's trichrome staining was performed for control groups taken from a collection of standard glass slides. RESULTS: In all 3 ARVD cases, RA anomalies were observed that revealed a reduction of cardiomyocytes, the presence of adipocytes, some of them inside the mediomural atrial layer and interstitial fibrosis. In 2 ARVD cases, interstitial fibrosis was also associated with a focus of replacement fibrosis, which was also observed in patients with permanent AF without ARVD. The histologic specimen of the RA and RV from the control group without cardiovascular disease did not display any evidence of fat or fibrosis with a preserved cardiomyocyte architecture. CONCLUSIONS: A similar histopathological substrate, as can be observed in the RV of patients with ARVD can also be seen in the RA of these patients. This may explain the high prevalence of atrial arrhythmias, particularly AF, in patients with ARVD.
Assuntos
Displasia Arritmogênica Ventricular Direita/patologia , Função do Átrio Direito , Remodelamento Atrial , Átrios do Coração/patologia , Adipócitos/patologia , Adulto , Displasia Arritmogênica Ventricular Direita/fisiopatologia , Autopsia , Estudos de Casos e Controles , Causas de Morte , Evolução Fatal , Feminino , Fibrose , Átrios do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Miócitos Cardíacos/patologiaRESUMO
Naxos disease, first described by Dr. Nikos Protonotarios and colleagues on the island of Naxos, Greece, is a special form of arrhythmogenic right ventricular dysplasia (ARVD). It is an inherited condition with a recessive form of transmission and a familial penetrance of 90%. It is associated with thickening of the skin of the hands and sole, and a propensity to woolly hair. The cardiac anomalies characterized by ventricular arrhythmias with ventricular extrasystoles and tachycardia and histologic features of the myocardium are consistent with ARVD, but in a more severe form of dysplasia with major dilatation of the right ventricle. The identification of the responsible first gene on chromosome 17, and its product plakoglobin as the responsible protein for Naxos disease proved to be a milestone in the study of ARVD, which opened a new field of research. Thanks to those with the determination to discover Naxos disease, there is and will be more clarity in understanding the mechanisms of juvenile sudden death in the young who have an apparently otherwise normal heart.
Assuntos
Displasia Arritmogênica Ventricular Direita/fisiopatologia , Doenças do Cabelo/fisiopatologia , Ceratodermia Palmar e Plantar/fisiopatologia , Animais , Displasia Arritmogênica Ventricular Direita/genética , Displasia Arritmogênica Ventricular Direita/mortalidade , Displasia Arritmogênica Ventricular Direita/patologia , Cromossomos Humanos Par 17/genética , Cromossomos Humanos Par 17/metabolismo , Morte Súbita , Doenças do Cabelo/genética , Doenças do Cabelo/mortalidade , Doenças do Cabelo/patologia , Humanos , Ceratodermia Palmar e Plantar/genética , Ceratodermia Palmar e Plantar/mortalidade , Ceratodermia Palmar e Plantar/patologia , gama Catenina/genética , gama Catenina/metabolismoRESUMO
Endomyocardial biopsy (EMB) is useful for the diagnosis of myocarditis, cardiac sarcoidosis, and non-ischemic cardiomyopathy. In this mini-review, we discuss the diagnostic potential of EMB in cases of acute/chronic-active myocarditis, sarcoidosis, idiopathic dilated cardiomyopathy and arrhythmogenic right ventricular dysplasia. We also summarize the complications caused by endomyocardial biopsy procedures. Importantly, we finally review the emerging molecular biology technologies as well as biological engineering techniques that can help improve the diagnostic accuracy of EMB to diagnose myocarditis and cardiomyopathies, promoting the management of these diseases.
RESUMO
The ECG is abnormal in most patients with arrhythmogenic right ventricular dysplasia (ARVD). Right ventricular parietal block, reduced QRS amplitude, epsilon wave, T wave inversion in V1-3 and ventricular tachycardia in the morphology of left bundle branch block are the characteristic changes that reflect the underlying genetic predetermined pathology and pathoelectrophysiology. Recognizing the characteristic ECG changes in ARVD will be of help in making a correct diagnosis of this rare disease.