An autoantibody to a calcium channel may play a role in idiopathic cardiac arrest, a preliminary study suggests.

Swiss researchers collected serum from 74 participants (mean age 52 years) in the Montreal Heart Institute hospital cohort and screened the serum samples for autoantibodies to 33 cardiac receptor proteins, including all known cardiac ion channel proteins.

They compared the “antibody signatures” of the serum samples taken from 23 people who had survived an idiopathic cardiac arrest, with 22 others whose cardiac arrest was due to myocardial ischaemia, and 29 healthy controls.

All individuals, even healthy ones, showed a wide range of IgG autoantibodies to cardiac membrane receptor proteins in their serum, the investigators reported.