Concealed arrhythmogenic syndromes: the hidden substrate of idiopathic ventricular fibrillation?

In similar to6-10% of survivors of cardiac arrest no cardiac abnormality ca n be identified despite extensive clinical evaluation. Autopsy data confirm that in a similar percentage of victims of sudden death no structural hear t disease can be identified at post mortem evaluation. Occurrence of cardia c arrest in the absence of a substrate is defined 'idiopathic ventricular f ibrillation' thus admitting that the cause for the arrhythmic event has rem ained unknown. We present data supporting the hypothesis that incompletely penetrant genetic defects may underlie at least some of these unexplained d eaths. (C) 2001 Elsevier Science B.V. All rights reserved.