<PAGE>

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

                                AMENDMENT NO.1 TO
                                   FORM 10-Q/A

[ X]   QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
       SECURITIES EXCHANGE ACT OF 1934

For the quarterly period ended         JUNE 30, 1998
                              --------------------------------------
                                       or

[  ]   TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
       SECURITIES EXCHANGE ACT OF 1934

For the transition period from _______________ to __________________

Commission File Number:               0-21330
                       ---------------------------------------------

                           AVECOR CARDIOVASCULAR INC.
-------------------------------------------------------------------------------
             (Exact name of registrant as specified in its charter)

               MINNESOTA                          41-1695729
-------------------------------------------------------------------------------
(State or other jurisdiction of     (I.R.S. Employer Identification No.)
 incorporation or organization)

         7611 NORTHLAND DRIVE, MINNEAPOLIS, MINNESOTA       55428
-------------------------------------------------------------------------------
         (Address of principal executive offices)         (Zip Code)

                                 (612) 391-9000
-------------------------------------------------------------------------------
              (Registrant's telephone number, including area code)

     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 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.

                                                     [ X ]  Yes    [   ]  No

     As of August 3, 1998, there were 8,044,475 shares of the registrant's $.01
par value Common Stock outstanding.

<PAGE>

                                      INDEX
<TABLE>
<CAPTION>

                                                                        Page(s)
                                                                        ------
<S>                                                                     <C>
Part I.  FINANCIAL  INFORMATION

      Item 2.   Management's Discussion and Analysis of Financial
                Condition and Results of Operations......................3 to 9

Part II.  OTHER  INFORMATION

      Item 2.   Changes in Securities and Use of Proceeds..................10

      Item 6.   Exhibits and Reports on Form 8-K...........................10

SIGNATURES.................................................................11

EXHIBIT INDEX..............................................................12

</TABLE>

                                       2
<PAGE>



                          PART I. FINANCIAL INFORMATION

ITEM 2.  MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL
         CONDITION AND RESULTS OF OPERATIONS

         The following is a discussion of the results of operations and
financial condition for the three and six month periods ended June 30, 1998
compared with the three and six month periods ended June 30, 1997 and should be
read in conjunction with the Company's Consolidated Financial Statements and
Notes thereto. The discussion set forth below reflects management's discussion
of historical results and trends in the business, financial condition, and
results of operations of the Company for periods prior to the public
announcement of the acquisition of the Company by Medtronic, Inc., discussed
below. There can be no assurance that the Company's business, financial
condition, and results of operations will not be adversely impacted as a result
of the announcement and, in particular, the effect of the announcement on the
Company's ability to sell its products through its distributors and sales
representatives.

OVERVIEW

         AVECOR Cardiovascular Inc. (the "Company") develops, manufactures and
markets specialty medical devices for heart/lung bypass surgery and long-term
respiratory support. The Company was incorporated on December 13, 1990, and in
June 1991, acquired the business and assets and assumed certain liabilities of
the surgical division of SCIMED Life Systems, Inc. (the "Predecessor Business").
On December 1, 1992, the Company acquired AVECOR Cardiovascular Ltd. (formerly
Cardio Med Ltd.), which previously had been a distributor for the Company in the
United Kingdom. In October 1995, the Company opened a sales office in France
which is organized as a wholly-owned subsidiary of AVECOR Cardiovascular Ltd.

         The assets acquired by the Company from the Predecessor Business
included the Company's line of solid silicone membrane oxygenators. Since that
time, the Company has engaged in extensive product development, resulting in the
introduction and receipt of regulatory approval from the U.S. Food and Drug
Administration (the "FDA") for the following proprietary products:

<TABLE>
<CAPTION>
                                PRODUCT                                 APPROVAL DATE
-----------------------------------------------------------------------------------------
<S>                                                                     <C> 
MYOTHERM-Registered Trademark- cardioplegia delivery system ............  October 1991

SIGNATURE-TM- custom tubing packs ......................................  July 1993

AFFINITY-Registered Trademark- oxygenator ..............................  November 1993

AFFINITY blood reservoirs ..............................................  July 1994

AFFINITY arterial filter ...............................................  October 1995

MYOTHERM XP-TM- (improved cardioplegia delivery system) ................  July 1997

AFFINITY blood pump ....................................................  August 1997

AFFINITY oxygenator with TRILLIUM-TM- bio-passive surface ..............  February 1998

</TABLE>

ACQUISITION OF THE COMPANY

         On July 12, 1998, Medtronic, Inc. ("Medtronic") and the Company
entered into an agreement under which Medtronic will acquire the Company in a
transaction valued at approximately $91 million. The transaction calls for the
Company's shareholders to receive $11.125 in Medtronic stock for each 

                                       3

<PAGE>

share of the Company's stock they hold at the transaction close date. In
addition to shareholder approval, the transaction is subject to customary
conditions including Hart-Scott-Rodino clearance. The companies expect
completion of the transaction in late 1998.

RESULTS OF OPERATIONS

NET SALES

THREE MONTHS ENDED JUNE 30, 1998 COMPARED TO THE THREE MONTHS ENDED 
JUNE 30, 1997

          Net sales increased 13% to $13,565,000 for the three months ended June
30, 1998 from $11,961,000 for the three months ended June 30, 1997. This
increase was primarily the result of a higher volume of product shipments of the
Company's AFFINITY line, SIGNATURE custom tubing pack line and the silicone
membrane oxygenator line. Sales growth in the AFFINITY line was positively
influenced by revenues from the AFFINITY blood pump. U.S. marketing approval for
the blood pump was received from the FDA in August 1997. Overall, average prices
of product shipments declined slightly when compared to the corresponding period
in 1997, principally due to competitive pressures.

          Sales from the AFFINITY, SIGNATURE custom tubing pack and silicone
membrane oxygenator lines increased approximately $974,000 (14.5%), $319,000
(12.7%) and $234,000 (13.6%), respectively, during the three months ended June
30, 1998 as compared to the three months ended June 30, 1997.

          During the third quarter of 1997, the Company terminated agreements
with its last remaining United States distributor and its only Canadian
distributor. These markets are now being served by the Company's direct sales
force. Sales in the territories formerly represented by these distributors
increased approximately $650,000 in the three month period ended June 30, 1998
as compared to the corresponding period in 1997. The Company cannot be certain
whether revenues in these territories will be maintained, improve or decline.

          Sales to customers located outside of the United States were
approximately 41% of net sales for each of the three month periods ended June
30, 1998 and 1997. Sales to customers located outside of the United States could
be adversely impacted in future periods as a result of the announcement of the
acquisition and the effect of that announcement on the Company's relationships
with its distributors and sales representatives.

          The Company has continued to experience decreased sales to contract
perfusion groups controlled by certain of its competitors. Sales to contract
perfusion groups controlled by one of the Company's competitors decreased
$235,000 to $117,000 for the three months ended June 30, 1998 from $352,000 for
the three months ended June 30, 1997. The Company believes that control of
contract perfusion groups by its competitors will continue to have a negative
impact on the Company's ability to market its products to such groups or to
hospitals or other medical providers that contract with competitor-controlled
groups for perfusion services, and could have a material adverse effect on the
Company's business, financial condition and results of operation. This
forward-looking statement is subject to the degree of control exerted by the
Company's competitors with respect to purchasing decisions made by controlled
groups of perfusionists, the extent of future acquisitions of contract perfusion
groups by the Company's competitors, the breadth of the Company's product
offerings relative to those competitors controlling contract perfusion groups,
and the degree to which the Company's research and development and marketing
efforts result in the successful commercialization of products with enhanced or
superior performance characteristics.

                                       4

<PAGE>

SIX MONTHS ENDED JUNE 30, 1998 COMPARED TO THE SIX MONTHS ENDED
JUNE 30, 1997

          Net sales increased 8% to $26,021,000 for the six months ended June
30, 1998 from $24,004,000 for the six months ended June 30, 1997. This increase
was primarily the result of a higher volume of product shipments of the
Company's SIGNATURE custom tubing pack line, AFFINITY line and the MYOTHERM
cardioplegia line. The Company received FDA marketing approval for its new
AFFINITY blood pump system in August 1997 and the MYOTHERM XP cardioplegia
delivery system in July 1997. These products positively influenced the
comparative sales growth. Overall, average prices of product shipments declined
slightly when compared to the corresponding period in 1997, principally due to
competitive pressures.

          Sales from the SIGNATURE custom tubing pack, AFFINITY and MYOTHERM
cardioplegia lines increased approximately $789,000 (16.5%), $784,000 (5.8%) and
$269,000 (13.8%), respectively, during the six months ended June 30, 1998 as
compared to the corresponding period in 1997.

          As noted above, the Company terminated agreements with its last
remaining United States distributor and its only Canadian distributor during the
third quarter of 1997 and these markets are now being served by the Company's
direct sales force. Sales in the territories formerly represented by these
distributors increased approximately $1,200,000 in the six months ended June 30,
1998 as compared to the six months ended June 30, 1997. The Company cannot be
certain whether revenues in these territories will be maintained, improve or
decline.

          Sales to customers located outside of the United States were
approximately 40% and 41% of net sales for the six month periods ended June 30,
1998 and 1997, respectively.

          Sales to contract perfusion groups controlled by one of the Company's
competitors decreased $458,000 to $258,000 for the six months ended June 30,
1998 from $716,000 for the six months ended June 30, 1997.

COST OF SALES / GROSS PROFIT

          Gross profit as a percentage of net sales decreased 1.0% to 41.3% for
the three months ended June 30, 1998 from 42.3% for the three months ended June
30, 1997. Similarly, gross profit as a percentage of net sales decreased 1.1% to
40.7% for the six months ended June 30, 1998 from 41.8% for the six months ended
June 30, 1997. The gross profit percentage for the three and six month periods
ended June 30, 1998 was unfavorably impacted by significant increases in sales
of the Company's lower-margin SIGNATURE custom tubing pack line as well as
competitive pricing pressures in the marketplace. Gross margins during the six
month period ended June 30, 1998 were also negatively impacted by the lower
production volumes experienced late in the fourth quarter of 1997 which
continued into the first quarter of 1998. The mix of products sold in any period
will influence the cost of sales and gross profit for the period.

          AFFINITY oxygenator product costs continued to decline due to
efficiency and material cost improvements, although these improvements were
largely offset by an ongoing decrease in average selling prices.

          The Company's future gross profit margin percentages will be
influenced by the ongoing pressures of the competitive pricing environment,
changes in the sales mix, the required levels of

                                       5

<PAGE>

production, new product introductions and the extent of further product cost
improvements through increased manufacturing efficiencies and reduced material
costs, if any. Given the uncertainty associated with new product introductions,
the ultimate realization of any such product cost improvements and the
continuing price pressures characteristic of the Company's markets, the Company
cannot be certain if its gross profit margin will be maintained, improve or
decline.

SELLING, GENERAL AND ADMINISTRATIVE

          Selling, general and administrative expenses increased 17% to
$4,075,000 for the three months ended June 30, 1998 from $3,482,000 for the
three months ended June 30, 1997. Selling, general and administrative expenses
increased 15% to $7,883,000 for the six months ended June 30, 1998 from
$6,832,000 for the six months ended June 30, 1997. These increases are primarily
attributed to costs associated with the continuing development of a direct sales
force in certain of the Company's territories formerly served by distributors
and independent sales representatives, marketing costs incurred for the
introduction of new products, including the AFFINITY blood pump, and increased
seasonal trade show costs. Various costs associated with the acquisition of the
Company also contributed to the incremental increase in selling, general and
administrative expenses during the three and six month periods ended June 30,
1998 as compared to the corresponding periods in 1997. As a percent of sales,
selling, general and administrative expenses increased to 30.0% and 30.3% for
the three and six month periods ended June 30, 1998, respectively, from 29.1%
and 28.5% for the three and six month periods ended June 30, 1997, respectively.

          Without considering the impact of the acquisition of the Company,
management anticipates that selling, general and administrative expenses for
1998 will be higher than 1997 and will approximate 1997 levels as a percentage
of sales. These forward-looking statements will be influenced by revenue
increases achieved by the Company, its ability to attract and retain qualified
sales personnel as the Company continues to develop its direct sales force, and
the timing and extent of promotional activities associated with the AFFINITY
oxygenator with TRILLIUM bio-passive surface, the new oxygen
saturation/hematocrit monitor and other new product introductions, if any.

RESEARCH AND DEVELOPMENT

          Research and development expenses decreased 8% to $895,000 from
$974,000 for the three month period ended June 30, 1998 and decreased 17% to
$1,726,000 from $2,076,000 for the six month periods ended June 30, 1997. This
decreased spending is a result of the transition from the completion or near
completion of major projects including the AFFINITY blood pump, MYOTHERM XP and
the AFFINITY oxygenator with TRILLIUM bio-passive surface to a new generation of
products including the new oxygen saturation/hematocrit monitor.

          Without considering the impact of the acquisition of the Company,
management anticipates that research and development expenses for 1998 will
approximate 1997 levels, as the Company continues to expand and improve its
proprietary line of disposable medical devices. This forward-looking projection
is dependent upon the extent and timing of new product development and the
impact of the regulatory process in obtaining marketing clearance for new
products, including the new oxygen saturation/hematocrit device which was
submitted for approval to the FDA near the end of the second quarter of 1998,
and the extent of expenses related to research studies commenced in an attempt
to prove the clinical efficacy and, thus, market advantage of the TRILLIUM
coating. The need or desire to modify the Company's existing products could also
influence the level of research and development expenses. There can be no
assurance, however, that the Company's research and development efforts will
result in

                                       6

<PAGE>

any additional regulatory submissions to the FDA or will result in any
commercially successful products. The forward-looking statements regarding
anticipated regulatory submissions contained in this paragraph will be impacted
by the results of the Company's development efforts, the availability of any
required clinical data, any changes in the regulatory scheme for such products,
and the Company's assessment of the cost and anticipated benefit of such
submissions.

INTEREST INCOME AND EXPENSE

          Interest income decreased to $78,000 for the three months ended June
30, 1998 from $129,000 for the three months ended June 30, 1997. Similarly,
interest income decreased to $164,000 for the six months ended June 30, 1998
from $273,000 for the six months ended June 30, 1997. This decrease in interest
income is primarily due to the use of cash and cash equivalents and investments
for the purchase of manufacturing molds and equipment and additional inventories
needed to support the Company's new products and revenue growth. At June 30,
1998, the majority of the Company's cash and cash equivalents was invested with
two investment portfolio managers who invested in bank certificates of deposit,
U.S. government securities, agency paper, money markets, commercial paper and
corporate obligations.

          Interest expense for the three and six month periods ended June 30,
1998 was $99,000 and $199,000, respectively, compared to $105,000 and $176,000
for the three and six month periods ended June 30, 1997, respectively. The
interest expense was exclusively due to the mortgage on the Company's U.S.
facility. The closing on the facility purchase occurred in late January 1997.

INCOME TAX PROVISION

          For the three and six month periods ended June 30, 1998 tax provisions
of $201,000 and $310,000 were recorded compared to tax provisions of $226,000
and $443,000 for three and six month periods ended June 30, 1997. The tax
provisions recorded correspond to the pretax income for those respective
periods. These provisions vary from the statutory U.S. federal corporate rate
primarily due to losses incurred by the Company's French subsidiary for which no
tax benefit has been recognized because of uncertainty of realization, partially
offset by the generation of research and experimentation credits.

NET INCOME

          Net income was $410,000 or $.05 per share, on a diluted basis, and
$630,000 or $.08 per share, on a diluted basis, for the three and six month
periods ended June 30, 1998, respectively, compared to $403,000 or $.05 per
share, on a diluted basis, and $790,000 or $.10 per share, on a diluted basis,
for the three and six month periods ended June 30, 1997, respectively.

LIQUIDITY AND CAPITAL RESOURCES

          For the six months ended June 30, 1998, the Company's operating
activities provided net cash of $2,848,000 compared to $479,000 provided by
operating activities for the same period in 1997. Net income after adjustments
for depreciation and amortization was $294,000 greater in the six months ended
June 30, 1998 as compared to the same period in 1997. The net change of
approximately $2,369,000 is primarily the result of increased accounts payable
balances principally due to the timing of check runs and increased accrued
expenses, and smaller increases in inventories and accounts receivable

                                       7

<PAGE>


when compared to the six months ended June 30, 1997. These net sources of cash
were partially offset by the use of cash for increased other current assets
during the six months ended June 30, 1998.

          Cash expenditures for capital additions totaled $2,090,000 for the six
months ended June 30, 1998 compared to $1,911,000 for six months ended June 30,
1997 when excluding the 1997 cash expenditures for the Company's U.S. facility
and related furniture, fixtures and equipment. These expenditures were primarily
related to equipment, molds and tooling necessary to further production,
increase production efficiencies, improve quality and reduce raw material costs
of the AFFINITY blood pump, MYOTHERM XP and the AFFINITY oxygenator and related
blood reservoirs. The investment in equipment for the six months ended June 30,
1998 includes $300,000 related to the AFFINITY blood pump. This pump equipment
is placed with customers in exchange for a long-term commitment to purchase
disposable products from the Company.

          Without considering the impact of the acquisition of the Company,
management anticipates capital expenditures for 1998 will be approximately
$4,000,000. This estimate includes additional equipment, molds and tooling for
the new oxygen saturation/hematocrit device, AFFINITY blood pump, MYOTHERM XP,
and for furthering production and related efficiencies of the AFFINITY
oxygenator line.

          The Company believes that its existing cash and cash equivalents and
investments as well as anticipated cash generated from operations will be
sufficient to satisfy the Company's cash requirements for the foreseeable
future.

          The foregoing forward-looking statements relating to the amount of
capital expenditures and ultimate cash usage are dependent on the progress of
the Company's product development efforts, the outcome of certain patent matters
(see Note 6), the timing of the receipt of FDA marketing clearances for any
future products and the investment made in opportunities to further existing
products' production related to production efficiencies and quality, and reduced
cost.

FOREIGN CURRENCY TRANSACTIONS

          Transactions by the Company's international subsidiaries are
negotiated, invoiced and paid in various foreign currencies, primarily pounds
sterling, and U.S. dollars. Accordingly, the Company is currently subject to
risks associated with fluctuations in exchange rates between the various
currencies.

          Substantially all of the Company's other international transactions
are denominated in U.S. dollars. Fluctuations in currency exchange rates in
other countries may therefore reduce the demand for the Company's products by
increasing the price of the Company's products in the currency of the countries
in which the products are sold.

YEAR 2000 ISSUES

          Computer programs have historically been written to abbreviate dates
by using two digits instead of four digits to identify a particular year. The
so-called "Year 2000" problem or "millennium bug" is the inability of computer
software or hardware to recognize or properly process dates ending in or after
"00." As the year 2000 approaches, significant attention is being focused on
updating or replacing such software and hardware in order to avoid system
failures, miscalculations or business interruptions that might otherwise result.

                                       8

<PAGE>

          The Company has reviewed its internal information systems and believes
that the costs and effort to address the Year 2000 problem will not be material
to its business, financial condition or results of operations, and, to the
extent necessary, may be resolved through replacement and upgrades to the
software it licenses from third parties. The Company has also reviewed its
ONCOURSE software product, the software embedded in its AFFINITY blood pump
console and the software for its saturation/hematocrit monitor under development
and believes them to be Year 2000 compliant. However, the Year 2000 problem may
also adversely impact the Company by affecting the business and operations of
parties with which the Company transacts business. The Company expects to
initiate formal communication with such parties regarding the Year 2000 problem
later in 1998. There can be no assurance that the Company will be able to
effectively address Year 2000 issues internally in a cost-efficient manner and
without interruption to its business, or that Year 2000 difficulties encountered
by its suppliers, customers or other parties will not have a material impact on
the Company's business, financial condition and results of operations.

NEW ACCOUNTING PRONOUNCEMENTS

          In June 1997, the Financial Accounting Standards Board issued
Statement of Financial Accounting Standards No. 131, "Disclosures About Segments
of an Enterprise and Related Information," a new standard of reporting
information about operating or business segments in financial statements. The
new standard will be effective for the Company's annual financial statements in
1998. Although the Company has not specifically evaluated what impact, if any,
this new standard will have on the Company's current reporting of operating and
business segments, the Company believes it will continue reporting as one
operating and business segment.

CERTAIN IMPORTANT FACTORS

          Except for the historical financial information contained herein, this
Form 10-Q contains certain forward-looking statements. For this purpose, any
statements contained in this Form 10-Q that are not statements of historical
fact may be deemed to be forward-looking statements. Without limiting the
foregoing, words such as "may," "will," "expect," "believe," "anticipate,"
"estimate" or "continue," the negative or other variations thereof, or
comparable terminology, are intended to identify forward-looking statements.
These statements by their nature involve substantial risks and uncertainties,
and actual results may differ materially depending on a variety of factors,
including the progress of product development and clinical studies, the timing
of and ability to obtain regulatory approvals, the extent to which the Company's
products gain market acceptance, the introduction of competitive products by
others, the pricing related to competitive products, litigation regarding patent
and other intellectual property rights, the availability of third-party
reimbursement and other factors. Additional information regarding these factors
is contained in the Company's Annual Report on Form 10-K for the year ended
December 31, 1997 under the heading "Important Factors."

                                       9
<PAGE>


                           PART II. OTHER INFORMATION

ITEM 2.   CHANGES IN SECURITIES AND USE OF PROCEEDS.

               In approving the execution and delivery of an Agreement and Plan
               of Merger between the Company and Medtronic, dated July 12, 1998
               (the "Merger Agreement"), on July 12, 1998 the Company's Board of
               Directors also approved certain amendments to the Rights
               Agreement, dated June 26, 1996 and as first amended July 22,
               1997, by and between the Company and Norwest Bank Minnesota, N.A.
               (the "Rights Agreement"). These amendments are reflected in a
               second amendment to the Rights Agreement also dated July 12, 1998
               (the "Second Amendment to Rights Agreement") and were adopted for
               the purpose of clarifying certain provisions of the Rights
               Agreement with respect to the Company's merger with Medtronic or
               any similar transaction.

               On August 21, 1998 the Company's Board of Directors approved an
               additional amendment to the Rights Agreement, providing that
               Medtronic will not be deemed to be an "Adverse Person" (as
               defined in the Rights Agreement) as a result of its beneficial
               ownership of Company Common Stock under the stock option
               agreement and certain voting agreements entered into pursuant to
               the Merger Agreement. This amendment is reflected in a third
               amendment to the Rights Agreement (the "Third Amendment to Rights
               Agreement") between the Company and Norwest Bank Minnesota N.A.,
               dated August 21, 1998.

               The Second Amendment to Rights Agreement and Third Amendment to
               Rights Agreement are attached hereto as Exhibits 4.1 and 4.2,
               respectively and are incorporated herein by reference.

ITEM 6.  EXHIBITS AND REPORTS ON FORM 8-K.

               (a)  Exhibits:

                    The exhibits to this Quarterly Report on Form 10-Q are
                    listed in the Exhibit Index beginning on page 13 of this
                    Report.

               (b)  Reports on Form 8-K:

                    None

                                       10


<PAGE>


                                   SIGNATURES

          Pursuant to the requirements of the Securities Exchange Act of 1934,
the registrant has duly caused this Amendment No. 1 to Form 10-Q to be signed on
its behalf by the undersigned thereunto  duly authorized.

                                             AVECOR CARDIOVASCULAR INC.

             August 28, 1998                 By /s/ Anthony Badolato
---------------------------------------      ---------------------------------
                Date                         Anthony Badolato
                                             Chief Executive Officer

             August 28, 1998                 By /s/ Gregory J. Melsen
---------------------------------------      ---------------------------------
                Date                         Gregory J. Melsen
                                             Vice President-Finance,
                                             Treasurer and Chief
                                             Financial Officer
                                             (Principal Financial and
                                             Accounting Officer)


                                       11

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                           AVECOR CARDIOVASCULAR INC.

                        EXHIBIT INDEX TO QUARTERLY REPORT
                                  ON FORM 10-Q

                       For the Quarter Ended June 30, 1998
                       -----------------------------------
<TABLE>
<CAPTION>


Item No.                            Description                                            Method of Filing
--------                            -----------                                            ----------------

<C>       <C>                                                                       <C>                      
2.1       Agreement and Plan of Merger, dated July 12, 1998, by and among AVECOR
          Cardiovascular Inc., AC Merger Corp. and Medtronic, Inc. (Omitted from
          this Exhibit, as filed, are the exhibits referenced in such agreement.
          AVECOR will furnish supplementally a copy of any such exhibits to the
          Commission upon request.)                                                 Filed herewith electronically*

2.2       Stock Option Agreement, dated July 12, 1998, by and between AVECOR
          Cardiovascular Inc. and Medtronic, Inc.                                   Filed herewith electronically*

4.1       Second Amendment to Rights Agreement, dated July 12, 1998, by and
          between AVECOR Cardiovascular Inc. and Norwest Bank Minnesota, N.A.       Filed herewith electronically*

4.2       Third Amendment to Rights Agreement, dated August 21, 1998 by and
          between AVECOR Cardiovascular Inc. and Norwest Bank Minnesota, N.A.       Filed herewith electronically

27. 1     Financial Data Schedule                                                   Filed herewith electronically*
</TABLE>


------------------------------

*Indicates item previously filed.

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