title: Consequence of patient substitution of nattokinase for warfarin after aortic valve replacement with a mechanical prosthesis.
abstract: This report describes a patient's self-substitution of nattokinase for the vitamin K antagonist warfarin after aortic valve replacement with a mechanical prosthesis. Nattokinase is an enzyme derived from a popular fermented soybean preparation in Japan (natto), which has fibrinolytic properties and is gaining popularity in nontraditional health journals and nonmedical health websites as an over-the-counter thrombolytic. After nearly a year of use of nattokinase without warfarin, the patient developed thrombus on the mechanical valve and underwent successful repeat valve replacement. We believe this is the first documented case of nattokinase being used as a substitute for warfarin after valve replacement, and we strongly discourage its use for this purpose.
authors.affiliation: Division of Cardiothoracic Surgery, Department of Surgery, Texas A&M Health Science Center at Scott & White Memorial Hospital, 2401 S. 31st Street, Temple, TX 76508. Dr. Shake is now at the University of Mississippi Medical Center.
authors.forename: Maqsood M
authors.initials: MM
authors.lastname: Elahi
authors.affiliation: Division of Cardiothoracic Surgery, Department of Surgery, Texas A&M Health Science Center at Scott & White Memorial Hospital, 2401 S. 31st Street, Temple, TX 76508. Dr. Shake is now at the University of Mississippi Medical Center.
authors.forename: Charles H
authors.initials: CH
authors.lastname: Choi
authors.affiliation: Division of Cardiothoracic Surgery, Department of Surgery, Texas A&M Health Science Center at Scott & White Memorial Hospital, 2401 S. 31st Street, Temple, TX 76508. Dr. Shake is now at the University of Mississippi Medical Center.
authors.forename: Subbareddy
authors.initials: S
authors.lastname: Konda
authors.affiliation: Division of Cardiothoracic Surgery, Department of Surgery, Texas A&M Health Science Center at Scott & White Memorial Hospital, 2401 S. 31st Street, Temple, TX 76508. Dr. Shake is now at the University of Mississippi Medical Center.
authors.forename: Jay G
authors.initials: JG
authors.lastname: Shake