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                                  UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

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                                  FORM 10-Q/A

                               (Amendment No. 1)

[X]  Quarterly report pursuant to Section 13 or 15(d) of the Securities Exchange
     Act of 1934

                  FOR THE QUARTERLY PERIOD ENDED JUNE 30, 2005

                           COMMISSION FILE NO. 0-18602

                                ATS MEDICAL, INC.
             (Exact name of registrant as specified in its charter)

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<S>                                                          <C>
                MINNESOTA                                         41-1595629
     (State or other jurisdiction of                           (I.R.S. Employer
      incorporation or organization)                         Identification No.)
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<S>                                                               <C>
    3905 ANNAPOLIS LANE N., SUITE 105
         MINNEAPOLIS, MINNESOTA                                      55447
(Address of principal executive offices)                          (Zip Code)
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       Registrant's telephone number, including area code: (763) 553-7736

                                 Not Applicable
             (Former name, former address and former fiscal year, if
                           changed since last report)

     Indicate by check mark whether the registrant (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days.

                               Yes   X   No
                                   -----    -----

     Indicate by check mark whether the registrant is an accelerated filer (as
defined in Rule 12b-2 of the Exchange Act).

                               Yes   X   No
                                   -----    -----

     The number of shares outstanding of each of the registrant's classes of
common stock as of July 29, 2005, was:

                Common Stock, $.01 par value   31,007,693 shares

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                                EXPLANATORY NOTE

This Amendment No. 1 on Form 10-Q/A (the "Form 10-Q/A") to our Quarterly Report
on Form 10-Q for the fiscal quarter ended June 30, 2005, initially filed with
the Securities and Exchange Commission (the "SEC") on August 8, 2005 (the
"Original Filing"), is being filed in response to comments received from the SEC
on the confidential treatment request with respect to Exhibits 10.2 and 10.3.
Item 6 of Part II of the Original Filing has been amended to incorporate revised
redacted versions of Exhibits 10.2 and 10.3.

In addition, pursuant to the rules of the SEC, Item 6 of Part II of the Original
Filing has been amended to contain currently-dated certifications from our Chief
Executive Officer and Chief Financial Officer, as required by Section 302 of the
Sarbanes-Oxley Act of 2002. The certifications of our Chief Executive Officer
and Chief Financial Officer are attached to this Form 10-Q/A as Exhibits 31.1
and 31.2, respectively.

Except for the foregoing amended information, this Form 10-Q/A continues to
describe conditions as of the date of the Original Filing, and we have not
updated the disclosures contained herein to reflect events that occurred at a
later date.


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                           PART II OTHER INFORMATION

ITEM 6. EXHIBITS

Note: Item 6 in the Original Filing is unchanged except for the filing of
replacement versions of Exhibits 10.2 and 10.3 and of additional certifications
pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.

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<S>         <C>
     10.2*  Marketing Services Agreement with Alabama Tissue Center, Inc. (also
            known as Regeneration Technologies, Inc. - Cardiovascular), a
            subsidiary of Regeneration Technologies, Inc., effective as of July
            21, 2005 (Incorporated by reference to Exhibit 10.43 to the
            Company's Annual Report on Form 10-K for the year ended December 31,
            2005)

     10.3*  Exclusive Development, Supply and Distribution Agreement with
            Genesee BioMedical, Inc., dated June 23, 2005 (Incorporated by
            reference to Exhibit 10.44 to the Company's Annual Report on Form
            10-K for the year ended December 31, 2005)

     31.1   Certification of Chief Executive Officer pursuant to Rules
            13a-15(e)/15d-15(e) (Section 302 Certification)

     31.2   Certification of Chief Financial Officer pursuant to Rules
            13a-15(e)/15d-15(e) (Section 302 Certification)
</TABLE>

*    Pursuant to Rule 24b-2 of the Securities Exchange Act of 1934, as amended,
     confidential portions of these exhibits have been deleted and filed
     separately with the Securities and Exchange Commission pursuant to a
     request for confidential treatment.


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                                   SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this amendment to be signed on its behalf by the
undersigned thereunto duly authorized.

Date: July 17, 2006                 ATS MEDICAL, INC.


                                    By: /s/ Michael D. Dale
                                        ----------------------------------------
                                        Michael D. Dale, Chief Executive Officer
                                        (Duly Authorized Officer)


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                                 EXHIBIT INDEX

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EXHIBIT
 NUMBER                                 DESCRIPTION
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<S>       <C>
 10.2*    Marketing Services Agreement with Alabama Tissue Center, Inc. (also
          known as Regeneration Technologies, Inc. - Cardiovascular), a
          subsidiary of Regeneration Technologies, Inc., effective as of July
          21, 2005 (Incorporated by reference to Exhibit 10.43 to the
          Company's Annual Report on Form 10-K for the year ended December 31,
          2005)

 10.3*    Exclusive Development, Supply and Distribution Agreement with
          Genesee BioMedical, Inc., dated June 23, 2005 (Incorporated by
          reference to Exhibit 10.44 to the Company's Annual Report on Form
          10-K for the year ended December 31, 2005)

 31.1     Certification of the Chief Executive Officer pursuant to Rules
          13a-15(e)/15d-15(e) (Section 302 Certification)

 31.2     Certification of the Chief Financial Officer pursuant to Rules
          13a-15(e)/15d-15(e) (Section 302 Certification)
</TABLE>

*    Pursuant to Rule 24b-2 of the Securities Exchange Act of 1934, as amended,
     confidential portions of these exhibits have been deleted and filed
     separately with the Securities and Exchange Commission pursuant to a
     request for confidential treatment.


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