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               CERTIFICATE OF DESIGNATIONS OF RIGHTS, PREFERENCES
                                AND PRIVILEGES OF
                     SERIES A PARTICIPATING PREFERRED STOCK
                              OF HEARTSTREAM, INC.


     The undersigned, Alan Levy and James Shay do hereby certify:

     1.   That they are the duly elected and acting President and Secretary,
respectively, of Heartstream, Inc., a Delaware corporation (the "CORPORATION").

     2.   That pursuant to the authority conferred upon the Board of Directors
by the Certificate of Incorporation of the said Corporation, the said Board of
Directors on December 6, 1996 adopted the following resolution creating a series
of 30,000 shares of Preferred Stock designated as Series A Participating
Preferred Stock:

     "RESOLVED, that pursuant to the authority vested in the Board of Directors
of the corporation by the Restated Certificate of Incorporation, the Board of
Directors does hereby provide for the issue of a series of Preferred Stock of
the Corporation and does hereby fix and herein state and express the
designations, powers, preferences and relative and other special rights and the
qualifications, limitations and restrictions of such series of Preferred Stock
as follows:

     Section 1.     DESIGNATION AND AMOUNT.  The shares of such series shall be
designated as "SERIES A PARTICIPATING PREFERRED STOCK." The Series A
Participating Preferred Stock shall have a par value of $0.001 per share, and
the number of shares constituting such series shall be 30,000.

     Section 2.     PROPORTIONAL ADJUSTMENT.  In the event the Corporation shall
at any time after the issuance of any share or shares of Series A Participating
Preferred Stock (i) declare any dividend on Common Stock of the Corporation
("COMMON STOCK") payable in shares of Common Stock, (ii) subdivide the
outstanding Common Stock or (iii) combine the outstanding Common Stock into a
smaller number of shares, then in each such case the Corporation shall
simultaneously effect a proportional adjustment to the number of outstanding
shares of Series A Participating Preferred Stock.

     Section 3.     DIVIDENDS AND DISTRIBUTIONS.

            (a)     Subject to the prior and superior right of the holders of
any shares of any series of Preferred Stock ranking prior and superior to the
shares of Series A Participating Preferred Stock with respect to dividends, the
holders of shares of Series A Participating Preferred 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 last day
of January, April, July and October 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 Series A Participating Preferred


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Stock, in an amount per share (rounded to the nearest cent) equal to 1,000 times
the aggregate per share amount of all cash dividends, and 1,000 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 Payment Date, since the first issuance of any share or fraction of a
share of Series A Participating Preferred Stock.

            (b)     The Corporation shall declare a dividend or distribution on
the Series A Participating Preferred Stock as provided in paragraph (a) above
immediately after it declares a dividend or distribution on the Common Stock
(other than a dividend payable in shares of Common Stock).

            (c)     Dividends shall begin to accrue on outstanding shares of
Series A Participating Preferred Stock from the Quarterly Dividend Payment Date
next preceding the date of issue of such shares of Series A Participating
Preferred Stock, unless the date of issue of such shares is prior to the record
date for the first Quarterly Dividend Payment Date, in which case dividends on
such shares shall begin to accrue from the date of issue of such shares, or
unless the date of issue is a Quarterly Dividend Payment Date or is a date after
the record date for the determination of holders of shares of Series A
Participating Preferred Stock entitled to receive a quarterly dividend and
before such Quarterly Dividend Payment Date, in either of which events such
dividends shall begin to accrue from such Quarterly Dividend Payment Date.
Accrued but unpaid dividends shall not bear interest.  Dividends paid on the
shares of Series A Participating Preferred Stock 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 shares of Series A Participating Preferred Stock
entitled to receive payment of a dividend or distribution declared thereon,
which record date shall be no more than 30 days prior to the date fixed for the
payment thereof.

     Section 4.     VOTING RIGHTS.  The holders of shares of Series A
Participating Preferred Stock shall have the following voting rights:

            (a)     Each share of Series A Participating Preferred Stock shall
entitle the holder thereof to 1,000 votes on all matters submitted to a vote of
the stockholders of the Corporation.

            (b)     Except as otherwise provided herein or by law, the holders
of shares of Series A Participating Preferred Stock and the holders of shares of
Common Stock shall vote together as one class on all matters submitted to a vote
of stockholders of the Corporation.

            (c)     Except as required by law, holders of Series A Participating
Preferred Stock 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.

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     Section 5.     CERTAIN RESTRICTIONS.

            (a)     The Corporation shall not declare any dividend on, make any
distribution on, or redeem or purchase or otherwise acquire for consideration
any shares of Common Stock after the first issuance of a share or fraction of a
share of Series A Participating Preferred Stock unless concurrently therewith it
shall declare a dividend on the Series A Participating Preferred Stock as
required by Section 3 hereof.

            (b)     Whenever quarterly dividends or other dividends or
distributions payable on the Series A Participating Preferred Stock as provided
in Section 3 are in arrears, thereafter and until all accrued and unpaid
dividends and distributions, whether or not declared, on shares of Series A
Participating Preferred Stock outstanding shall have been paid in full, the
Corporation shall not

                    (i)    declare or pay dividends on, make any other
distributions on, or redeem or purchase or otherwise acquire for consideration
any shares of stock ranking junior (either as to dividends or upon liquidation,
dissolution or winding up) to the Series A Participating Preferred Stock;

                    (ii)   declare or pay dividends on, 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 Series A Participating
Preferred Stock, except dividends paid ratably on the Series A Participating
Preferred Stock 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 on a parity (either as to dividends or
upon liquidation, dissolution or winding up) with the Series A Participating
Preferred Stock, provided that the Corporation may at any time redeem, purchase
or otherwise acquire shares of any such parity 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 Series A Participating Preferred
Stock;

                    (iv)   purchase or otherwise acquire for consideration any
shares of Series A Participating Preferred Stock, or any shares of stock ranking
on a parity with the Series A Participating Preferred Stock, 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.

            (c)     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

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Corporation could, under paragraph (a) of this Section 5, purchase or otherwise
acquire such shares at such time and in such manner.

     Section 6.     REACQUIRED SHARES.  Any shares of Series A Participating
Preferred Stock 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 to be created by resolution or resolutions of the Board of
Directors, subject to the conditions and restrictions on issuance set forth
herein and, in the Restated Certificate of Incorporation, as then amended.

     Section 7.     LIQUIDATION, DISSOLUTION OR WINDING UP.  Upon any
liquidation, dissolution or winding up of the Corporation, the holders of shares
of Series A Participating Preferred Stock shall be entitled to receive an
aggregate amount per share equal to 1000 times the aggregate amount to be
distributed per share to holders of shares of Common Stock plus an amount equal
to any accrued and unpaid dividends on such shares of Series A Participating
Preferred Stock.

     Section 8.     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 the shares of
Series A Participating Preferred Stock shall at the same time be similarly
exchanged or changed in an amount per share equal to 1,000 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.

     Section 9.     NO REDEMPTION.  The shares of Series A Participating
Preferred Stock shall not be redeemable.

     Section 10.    RANKING.  The Series A Participating Preferred Stock shall
rank junior to all other series of the Corporation's Preferred Stock as to the
payment of dividends and the distribution of assets, unless the terms of any
such series shall provide otherwise.

     Section 11.    AMENDMENT.  The Restated Certificate of Incorporation of the
Corporation shall not be further amended in any manner which would materially
alter or change the powers, preference or special rights of the Series A
Participating Preferred Stock so as to affect them adversely without the
affirmative vote of the holders of a majority of the outstanding shares of
Series A Participating Preferred Stock, voting separately as a class.

     Section 12.    FRACTIONAL SHARES.  Series A Participating Preferred Stock
may be issued in fractions of a share which shall entitle the holder, in
proportion to such holder's fractional shares, to exercise voting rights,
receive dividends, participate in distributions and to have the benefit of all
other rights of holders of Series A Participating Preferred Stock.

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     RESOLVED FURTHER, that the President or any Vice President and the
Secretary or any Assistant Secretary of this corporation be, and they hereby
are, authorized and directed to prepare and file a Certificate of Designation of
Rights, Preferences and Privileges in accordance with the foregoing resolution
and the provisions of Delaware law and to take such actions as they may deem
necessary or appropriate to carry out the intent of the foregoing resolution."

     We further declare under penalty of perjury that the matters set forth in
the foregoing Certificate of Designation are true and correct of our own
knowledge.

     Executed at Seattle, Washington on December 6, 1996.



                                        /s/ ALAN LEVY
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                                        Alan Levy, President



                                        /s/ JAMES SHAY
                                        ----------------------------------------
                                        James Shay, Secretary