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                                                                    EXHIBIT 4.13

                            ACTION BY WRITTEN CONSENT

                             OF THE STOCKHOLDERS OF

                              3F THERAPEUTICS, INC.
                             a Delaware corporation

         The undersigned stockholders of 3F Therapeutics, Inc., a Delaware
corporation, do hereby dispense with the formality of a meeting and adopt and
approve the following resolutions:

                  WHEREAS, this Corporation, ATS Medical, Inc., a Minnesota
         corporation ("Parent"), Seabiscuit Acquisition Corp., a Delaware
         corporation ("Merger Subsidiary") and a wholly-owned subsidiary of
         Parent, and Boyd D. Cox, as the Stockholder Representative (the
         "Stockholder Representative"), are parties to that certain Agreement
         and Plan of Merger, dated as of January 23, 2006 (the "Merger
         Agreement"), providing for the acquisition by Parent of this
         Corporation through a merger of Merger Subsidiary with and into this
         Corporation, with this Corporation being the surviving entity and thus
         becoming a wholly owned subsidiary of Parent.

                  WHEREAS, the merger contemplated by the Merger Agreement (the
         "Merger") and the Merger Agreement and the principal terms thereof were
         adopted and approved by the stockholders of this Corporation.

                  WHEREAS, the Board of Directors of this Corporation believes
         that it is in the best interests of this Corporation to amend the
         Merger Agreement to, among other things, (a) extend the termination
         date thereunder from June 15, 2006 to August 31, 2006, (b) provide what
         happens in the event that all options to purchase shares of this
         Corporation's common stock are not exercised or terminated prior to the
         effective time of the Merger as required by the Merger Agreement and
         (c) expressly provide Parent with indemnification for certain lawsuits
         filed against this Corporation, Theodore C. Skokos (a director and
         Chairman of the Board of this Corporation), and 3F Partners Limited
         Partnership II (a limited partnership, the general partner of which is
         3F Management II, LLC of which Mr. Skokos is the President).

                  WHEREAS, based on the foregoing, the Board of Directors of
         this Corporation has adopted and approved of that certain Amendment No.
         1 to Agreement and Plan of Merger, dated as of June 13, 2006, by and
         among this Corporation, Parent, Merger Subsidiary and the Stockholder
         Representative (the "Amendment"), a copy of which is attached hereto as
         Exhibit "A".

                  WHEREAS, the Board of Directors of this Corporation has
         declared the advisability of the Amendment and found that the Merger
         Agreement, as amended by the Amendment, is fair and in the best
         interests of the stockholders of this Corporation and has directed the
         officers of this Corporation to seek the approval of the stockholders
         of this Corporation to the Amendment.

                  NOW THEREFORE, BE IT HEREBY RESOLVED, that the Amendment, a
         copy of which is attached hereto as Exhibit "A", is hereby adopted and
         approved.

                  RESOLVED, FURTHER, that the Merger, the Merger Agreement and
         the principal terms of the Merger Agreement, as amended by the
         Amendment, are hereby adopted and approved.


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         This Action by Written Consent may be executed in one or more
counterparts, each of which shall be deemed an original and all of which shall
be deemed one and the same Action by Written Consent. Each of the undersigned is
executing this Action by Written Consent with respect to all shares of the
Common Stock and/or the Preferred Stock of this Corporation held by him, her or
it (and all shares shall be deemed to have been voted together as one class on
an as-converted to Common Stock basis; as to the Common Stock, such shares also
shall be deemed to have been voted on a separate class basis, if and to the
extent required by law; and as to the Preferred Stock, such shares also shall be
deemed to have been voted together as a separate class and, if and to the extent
required by law, on a separate series basis among each of the series thereof).

         This Action by Written Consent and any executed counterparts shall be
filed in the Book of Minutes of this Corporation and become a part of the
records of this Corporation.


________________________________________
Signature of 3F Therapeutics Stockholder




___________________________________________           Dated:              , 2006
Printed Name of 3F Therapeutics Stockholder                  -------------




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