We are revising the criteria in sections 4.00 and 104.00 of the Listing of Impairments, appendix 1 to subpart P of part 404 of our regulations, that we use to evaluate claims involving cardiovascular disorders in adults and children under titles II and XVI of the Social Security Act. The listings describe those disorders that we consider severe enough to prevent a person from engaging in any gainful activity, or that cause marked and severe functional limitations for a child claiming Supplemental Security Income payments under title XVI. These revisions reflect our adjudicative experience, advances in medical knowledge, and comments we received from experts and the public in response to an advance notice of proposed rulemaking, a notice of proposed rulemaking, and at an outreach policy conference in Baltimore, Maryland on September 24 and 25, 2008. Attendees included employees of various Social Security components, employees of Disability Determination Services offices, members of professional organizations such as the American Heart Association, university faculty, and other medical professionals.