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                                                                    Exhibit 3.3

                            CERTIFICATE OF DESIGNATIONS
                                         OF
                   SERIES A JUNIOR PARTICIPATING PREFERRED STOCK
                                         OF
                            ENDOCARDIAL SOLUTIONS, INC.



     The undersigned hereby certifies that the Board of Directors of
Endocardial Solutions, Inc. (the "Corporation"), a corporation organized and
existing under the Delaware General Corporation Law, in accordance with the
provisions of the Delaware General Corporation Law, Section 151, duly adopted
the following resolution on August 24, 1999:

     RESOLVED, that a series of preferred stock of the Corporation is hereby
created, and the designation and amount thereof and the relative rights and
preferences of the shares of such series, are as follows:

     Section 1.  DESIGNATION AND AMOUNT. The shares of such series shall be
designated as "Series A Junior Participating Preferred Stock" (the "Preferred
Shares"), par value $.01 per share, and the number of shares constituting the
Preferred Shares shall be 400,000. Such number of shares may be increased or
decreased by resolution of the Board of Directors and any necessary
shareholder approval; PROVIDED, HOWEVER, that no decrease shall reduce the
number of shares of Preferred Shares to a number less than the number of
shares then outstanding plus the number of shares reserved for issuance upon
the exercise of outstanding options, rights or warrants or upon the
conversion of any outstanding securities issued by the Corporation
convertible into Preferred Shares.

     Section 2.  DIVIDENDS AND DISTRIBUTIONS.

     (a)  Subject to the rights of the holders of any shares of any series of
preferred stock (or any similar stock) ranking prior and superior to the
Preferred Shares with respect to dividends, the holders of Preferred Shares,
in preference to the holders of Common Stock (the "Common Stock"), of the
Corporation, and of any other junior stock, shall be entitled to receive,
when, as and if declared by the Board of Directors out of funds legally
available for the purpose, quarterly dividends payable in cash on the 1st day
of March, June, September and December in each year (each such date being
referred to herein as a "Quarterly Dividend Payment Date"), commencing on the
first Quarterly Dividend Payment Date after the first issuance of a share or
fraction of a share of Preferred Shares, in an amount per share (rounded to
the nearest cent) equal to the greater of (i) $1.00 or (ii) subject to the
provision for adjustment hereinafter set forth, 100 times the aggregate per
share amount of all cash dividends, and 100 times the aggregate per share
amount (payable in kind) of all non-cash dividends or other distributions,
other than a dividend payable in shares of Common Stock or a subdivision of
the outstanding shares of Common Stock (by reclassification or otherwise),
declared on the Common Stock since the immediately preceding Quarterly
Dividend Payment Date or, with respect to the first Quarterly Dividend


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Payment Date, since the first issuance of any share or fraction of a share of
Preferred Shares. In the event the Corporation shall at any time after
September 15, 1999, declare or pay any dividend on the Common Stock payable
in shares of Common Stock, or effect a subdivision or combination or
consolidation of the outstanding shares of Common Stock (by reclassification
or otherwise) into a greater or lesser number of shares of Common Stock, then
in each such case the amount to which holders of shares of Preferred Shares
were entitled immediately prior to such event under clause (ii) of the
preceding sentence shall be adjusted by multiplying such amount by a
fraction, the numerator of which is the number of shares of Common Stock
outstanding immediately after such event and the denominator of which is the
number of shares of Common Stock that were outstanding immediately prior to
such event.

     (b)  The Corporation shall declare a dividend or distribution on the
Preferred Shares as provided in paragraph (a) of this Section immediately
after it declares a dividend or distribution on the Common Stock (other than
a dividend payable in shares of Common Stock or a subdivision of the
outstanding Common Stock); provided that, in the event no dividend or
distribution shall have been declared on the Common Stock during the period
between any Quarterly Dividend Payment Date and the next subsequent Quarterly
Dividend Payment Date, a dividend of $1.00 per share on the Preferred Shares
shall nevertheless be payable, out of funds legally available for such
purpose, on such subsequent Quarterly Dividend Payment Date.

     (c)  Dividends shall begin to accrue and be cumulative on outstanding
shares of Preferred Shares from their date of issue. Accrued but unpaid
dividends shall not bear interest. Dividends paid on the shares of Preferred
Shares in an amount less than the total amount of such dividends at the time
accrued and payable on such shares shall be allocated pro rata on a
share-by-share basis among all such shares at the time outstanding. The
Board of Directors may fix a record date for the determination of holders of
Preferred Shares entitled to receive payment of a dividend or distribution
declared thereon, which record date shall be not more than 60 days prior to
the date fixed for the payment thereof.

     Section 3.  VOTING RIGHTS.

     (a)  Subject to the provision for adjustment hereinafter set forth, each
Preferred Share shall entitle the holder thereof to 100 votes on all matters
submitted to a vote of the shareholders of the Corporation. In the event the
Corporation shall at any time after September 15, 1999, declare or pay any
dividend on the Common Stock payable in shares of Common Stock, or effect a
subdivision or combination or consolidation of the outstanding shares of
Common Stock (by reclassification or otherwise) into a greater or lesser
number of shares of Common Stock, then in each such case the number of votes
per share to which holders of shares of Preferred Shares were entitled
immediately prior to such event shall be adjusted by multiplying such number
by a fraction, the numerator of which is the number of shares of Common Stock
outstanding immediately after such event and the denominator of which is the
number of shares of Common Stock that were outstanding immediately prior to
such event.


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     (b)  Except as otherwise provided herein or by law, the holders of
Preferred Shares and the holders of Common Stock and any other capital stock
of the Corporation having general voting rights shall vote together as one
class on all matters submitted to a vote of shareholders of the Corporation.

     (c)  Except as set forth herein or required by law, holders of Preferred
Shares shall have no special voting rights and their consent shall not be
required (except to the extent they are entitled to vote with holders of
Common Stock as set forth herein) for taking any corporate action.

     Section 4.  CERTAIN RESTRICTIONS.

     (a)  Whenever quarterly dividends or other dividends or distributions
payable on the Preferred Shares as provided in Section 2 are in arrears,
thereafter and until all accrued and unpaid dividends and distributions,
whether or not declared, on shares of Preferred Shares outstanding shall have
been paid in full, the Corporation shall not:

          (i)   declare or pay dividends, or make any other distributions, on
     any shares of stock ranking junior (either as to dividends or upon
     liquidation, dissolution or winding up) to the Preferred Shares;

          (ii)  declare or pay dividends, or make any other distributions, on
     any shares of stock ranking on a parity (either as to dividends or upon
     liquidation, dissolution or winding up) with the Preferred Shares, except
     dividends paid ratably on the Preferred Shares and all such parity stock on
     which dividends are payable or in arrears in proportion to the total
     amounts to which the holders of all such shares are then entitled;

          (iii) redeem or purchase or otherwise acquire for consideration shares
     of any stock ranking junior (either as to dividends or upon liquidation,
     dissolution or winding up) to the Preferred Shares; PROVIDED, HOWEVER, that
     the Corporation may at any time redeem, purchase or otherwise acquire
     shares of any such junior stock in exchange for shares of any stock of the
     Corporation ranking junior (either as to dividends or upon dissolution,
     liquidation or winding up) to the Preferred Shares; or

          (iv)  redeem or purchase or otherwise acquire for consideration any
     Preferred Shares, or any stock ranking on a parity with the Preferred
     Shares, except in accordance with a purchase offer made in writing or by
     publication (as determined by the Board of Directors) to all holders of
     such shares upon such terms as the Board of Directors, after consideration
     of the respective annual dividend rates and other relative rights and
     preferences of the respective series and classes, shall determine in good
     faith will result in fair and equitable treatment among the respective
     series or classes.


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     (b)  The Corporation shall not permit any subsidiary of the Corporation
to purchase or otherwise acquire for consideration any shares of stock of the
Corporation unless the Corporation could, under paragraph (a) of this
Section 4, purchase or otherwise acquire such shares at such time and in such
manner.

     Section 5.  REACQUIRED SHARES. Any Preferred Shares purchased or
otherwise acquired by the Corporation in any manner whatsoever shall be
retired and canceled promptly after the acquisition thereof. All such shares
shall upon their cancellation become authorized but unissued shares of
preferred stock and may be reissued as part of a new series of preferred
stock subject to the conditions and restrictions on issuance set forth
herein, in the certificate of incorporation, or in any other certificate of
designation creating a series of preferred stock or any similar stock or as
otherwise required by law.

     Section 6.  LIQUIDATION, DISSOLUTION OR WINDING UP. Upon any
liquidation, dissolution or winding up of the Corporation, no distribution
shall be made (1) to the holders of shares of stock ranking junior (either as
to dividends or upon liquidation, dissolution or winding up) to the Preferred
Shares unless, prior thereto, the holders of Preferred Shares shall have
received the greater of (i) $100 per share, plus an amount equal to accrued
and unpaid dividends and distributions thereon, whether or not declared, to
the date of such payment, or (ii) an aggregate amount per share, subject to
the provision for adjustment hereinafter set forth, equal to 100 times the
aggregate amount to be distributed per share to holders of Common Stock, or
(2) to the holders of stock ranking on a parity (either as to dividends or
upon liquidation, dissolution or winding up) with the Preferred Shares,
except distributions made ratably on the Preferred Shares and all such parity
stock in proportion to the total amounts to which the holders of all such
shares are entitled upon such liquidation, dissolution or winding up. In the
event the Corporation shall at any time after September 15, 1999, declare or
pay any dividend on the Common Stock payable in shares of Common Stock, or
effect a subdivision or combination or consolidation of the outstanding
shares of Common Stock (by reclassification or otherwise) into a greater or
lesser number of shares of Common Stock, then in each such case the aggregate
amount to which holders of shares of Preferred Shares were entitled
immediately prior to such event under clause (1)(ii) of the preceding
sentence shall be adjusted by multiplying such amount by a fraction the
numerator of which is the number of shares of Common Stock outstanding
immediately after such event and the denominator of which is the number of
shares of Common Stock that were outstanding immediately prior to such event.


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     Section 7.  CONSOLIDATION, MERGER, ETC. In case the Corporation shall
enter into any consolidation, merger, combination or other transaction in
which the shares of Common Stock are exchanged for or changed into other
stock or securities, cash and/or any other property, then in any such case
each share of Preferred Shares shall at the same time be similarly exchanged
or changed into an amount per share, subject to the provision for adjustment
hereinafter set forth, equal to 100 times the aggregate amount of stock,
securities, cash and/or any other property (payable in kind), as the case may
be, into which or for which each share of Common Stock is changed or
exchanged. In the event the Corporation shall at any time after September
15, 1999, declare or pay any dividend on the Common Stock payable in shares
of Common Stock, or effect a subdivision or combination or consolidation of
the outstanding shares of Common Stock (by reclassification or otherwise)
into a greater or lesser number of shares of Common Stock, then in each such
case the amount set forth in the preceding sentence with respect to the
exchange or change of shares of Preferred Shares shall be adjusted by
multiplying such amount by a fraction, the numerator of which is the number
of shares of Common Stock outstanding immediately after such event and the
denominator of which is the number of shares of Common Stock that were
outstanding immediately prior to such event.

     Section 8.  NO REDEMPTION. The Preferred Shares shall not be redeemable.

     Section 9.  RANK. The Preferred Shares shall rank, with respect to the
payment of dividends and the distribution of assets, junior to all series of
any other class of the Corporation's preferred stock.

     Section 10.  FRACTIONAL SHARES. Preferred Shares may be issued in
fractions of a share which are integral multiples of one one-hundredth of a
share which shall entitle the holder, in proportion to such holder's
fractional shares, to receive dividends, participate in distributions and to
have the benefit of all other rights of holders of Preferred Shares.

     Section 11.  AMENDMENT. The Articles of Incorporation of the
Corporation shall not be amended in any manner which would materially alter
or change the powers, preferences or rights of the Preferred Shares so as to
affect them adversely without the affirmative vote of the holders of at least
two-thirds of the outstanding shares of Preferred Shares, voting together as
a single class.

     IN WITNESS WHEREOF, I have subscribed my name this 25th day of August,
1999.

                                 ENDOCARDIAL SOLUTIONS, INC.


                                 By   /s/ Leota L. Pearson
                                    ------------------------------------------
                                      Leota L. Pearson
                                      Chief Financial Officer