Hopkins scientists analysed characteristics of 100 ARVD patients, including 69 while still alive and 31 diagnosed postmortem. The subjects included men and women of many ethnic backgrounds, with a median age of 31.
ARVD is composed of a range of symptoms, including irregular heartbeat and the presence of excess amounts of fatty tissue in the heart's right ventricle. A family history of sudden cardiac death at a young age is considered a major risk factor for the disorder. Athletes are at particular risk, but the precise biological reasons for this remain unknown.
Hugh Calkins, a professor of medicine and paediatrics at The Johns Hopkins University School of Medicine and its Heart Institute, notes that the disease frequently strikes people who are relatively young and that symptoms may appear up to 15 years before diagnosis.
Diagnosis of ARVD is based on a four-point scale, and up to ten cardiac tests are required to confirm a diagnosis. ECGs and echocardiograms are performed to verify the origins of arrhythmia, and MRI tests - backed up by tissue biopsy - are done to confirm the buildup of fat and fibrous tissue in the right ventricle. According to Calkins, these confirmatory tests are important because the illness is often misdiagnosed if physicians rely on a single diagnostic test.
In the study, of the 47 patients who were diagnosed early and implanted with defibrillators, only one died of cardiac arrest, when the heart suddenly stops functioning from a runaway heartbeat. 29 of the patients' defibrillators "fired" within two years. Of 22 patients without defibrillators and maintained on drug therapy alone, two died of cardiac arrest, in addition to the 31 who died before diagnosis.
MEDICA.de; Source: Johns Hopkins Medical Institutions