Response to Letter Regarding Article, "Outcome of Apparently Unexplained Cardiac Arrest: Results From Investigation and Follow-Up of the Prospective Cardiac Arrest Survivors With Preserved Ejection Fraction Registry". (April 2016) - Herman, Adam R.M.; Cheung, Christopher; Gerull, Brenda; Simpson, Christopher S.; Birnie, David H.; Klein, George J.; Champagne, Jean; Healey, Jeffrey S.; Gibbs, Karen; Talajic, Mario; Gardner, Martin; Bennett, Matthew T.; et al.