Rampazzo et al. (1995) performed studies in a family with a 'concealed' form of ARVD; affected members showed no change in heart size and had normal standard ECG and functional capacity, but consistently showed effort-induced polymorphic ventricular tachycardias. ... Rampazzo et al. (1995) performed studies in a family with a 'concealed' form of ARVD; affected members showed no change in heart size and had normal standard ECG and functional capacity, but consistently showed effort-induced polymorphic ventricular tachycardias. Juvenile sudden death had occurred in 4 members. Postmortem examination of 2 of these subjects showed a right ventricle of normal size, with no overt abnormalities. However, large areas of fatty-fibrous replacement, mostly localized in the subepicardial layer of the right ventricle, were demonstrated histologically. Scoote and Williams (2004) reviewed defects in cardiomyocyte calcium homeostasis and the associated arrhythmias.
Tiso et al. (2001) refined the physical mapping of the critical ARVD2 region, excluded ACTN2 and nidogen (NID; 131390) as candidate genes, elucidated the genomic structure of RYR2, and identified RYR2 mutations in 4 independent ARVD2 families. In ... Tiso et al. (2001) refined the physical mapping of the critical ARVD2 region, excluded ACTN2 and nidogen (NID; 131390) as candidate genes, elucidated the genomic structure of RYR2, and identified RYR2 mutations in 4 independent ARVD2 families. In myocardial cells the RYR2 protein, activated by Ca(2+), induces the release of calcium from the sarcoplasmic reticulum into the cytosol. RYR2 is the cardiac counterpart of RYR1 (180901), the skeletal muscle ryanodine receptor, which is involved in malignant hyperthermia susceptibility (MHS1; 145600) and in central core disease (CCD; 117000). The identified RYR2 mutations occurred in 2 highly conserved regions, strictly corresponding to those where mutations causing MHS1 or CCD are clustered in the RYR1 gene.