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                                                                    Exhibit A
                                                                    ---------

                           CERTIFICATE OF AMENDMENT
 
                                      OF

                                ECHOCATH, INC.
   
                          Pursuant to Title 14 A:9-4
                             Corporations, General

                           of the New Jersey Statutes

         Echocath,  Inc., a  corporation  organized  and  existing  under and by
virtue of the laws of the State of New Jersey (the  "Corporation"),  DOES HEREBY
CERTIFY that:

         First:    The name of the Corporation is:  Echocath, Inc.

         Second:   The amendment to the  Certificate of  Incorporation  effected
                   hereby is as follows:

         By adding a new Article IX to the Certificate of  Incorporation  in its
present form in the following form:

                                   Article IX
                         Series B Cumulative Convertible
                                 Preferred Stock

         1. Designation. There is hereby established a series of Preferred Stock
which is  designated  as  "Series  B  Cumulative  Convertible  Preferred  Stock"
(referred to herein as the "Series B Cumulative Convertible Preferred Stock").

         2.  Authorized  Number.  The  number  of shares  constituting  Series B
Cumulative Convertible Preferred Stock shall be 280,000.

         3.  Dividends.  Holders  of shares of Series B  Cumulative  Convertible
Preferred  Stock shall be entitled to  dividends  equal to $ .0675 per share per
quarter.  Said  dividend  shall be  payable on May 1,  August 1,  November 1 and
February 1 to the extent that the  Corporation  has earnings  and funds  legally
available  to pay such  dividend.  To the extent that the Company  does not have
earnings or funds are not legally available to pay a dividend,  then such amount
shall  be  accrued  as a  liability  on  the  books  of the  Corporation  and be
cumulative for the benefit of the shareholder. If a dividend on the Common Stock
is  declared  by  the  Board  of  Directors,   the  Board  of  Directors   shall
simultaneously  declare  a  dividend  on the  Series  B  Cumulative  Convertible
Preferred  Stock in an amount  per  share  equal to (a) the  product  of (i) the
dividend per share of Common  Stock,  multiplied by (ii) the number of shares of
Common Stock into which all of the outstanding  Series B Cumulative  Convertible
Preferred  Stock could then be converted,  divided by (b) the number of Series B
Cumulative  Convertible  Preferred  Stock then  outstanding,  and rounded to the
nearest cent, each such  determination  to be made as of the record date for the
determination  of the  dividend.  If a  dividend  is  declared  by the  Board of
Directors on any other class or series of stock,  the Board of  Directors  shall
simultaneously  declare  a  dividend  on the  Series  B  Cumulative  Convertible
Preferred  Stock in an amount per share equal to the  dividend per share of such
other class or series of stock.  The term  "dividend," when used in this Section
3,  shall  refer to any  dividend  which is not a stock  dividend  described  in
Section 8 (d) hereof.





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         4. Liquidation. Upon any liquidation,  dissolution or winding up of the
Corporation,  whether  voluntary  or  involuntary,  the holders of the shares of
Series B Cumulative  Convertible  Preferred Stock shall be entitled,  before any
distribution  or  payment is made upon any  Common  Stock or any other  class or
series of stock ranking junior to the Series B Cumulative  Convertible Preferred
Stock as to distribution of assets upon liquidation,  to be paid an amount equal
to $5.00 per share (the "Original Purchase Price"),  plus an amount equal to all
unpaid dividends, without interest, which have been declared on such outstanding
shares of Series B Cumulative  Convertible  Preferred Stock prior to the date of
the  liquidation  payment,  such  amounts  being  sometimes  referred  to as the
"Liquidation  Payment." If upon such  liquidation,  dissolution or winding up of
the Corporation,  whether voluntary or involuntary, the assets to be distributed
among the  holders of Series B  Cumulative  Convertible  Preferred  Stock of the
Corporation  shall be  insufficient to permit payment to the holders of Series B
Cumulative  Convertible  Preferred Stock of the entire amount of the Liquidation
Payment, then the entire assets of the Corporation available for distribution to
the  stockholders  shall be  distributed  ratably  among the holders of Series B
Cumulative  Convertible  Preferred  Stock in  proportion  to the full amounts to
which they are respectively  entitled, and the holders of the Common Stock shall
in no event be entitled to  participate  in the  distribution  of said assets in
respect of their shares. Upon any such liquidation, dissolution or winding up of
the Corporation,  after the holders of Series B Cumulative Convertible Preferred
Stock shall have been paid in full the amounts to which they shall be  entitled,
the remaining net assets of the Corporation  shall be distributed pro rata among
the holders of Common  Stock based on the number of shares of Common  Stock held
by each such holder. Written notice of such liquidation,  dissolution or winding
up, stating a payment date, the amount of the Liquidation  Payment and the place
where said Liquidation Payment shall be payable, shall be given by mail, postage
prepaid,  not less  then  thirty  (30) days  prior to the  payment  date  stated
therein, to the holders of record of Series B Cumulative  Convertible  Preferred
Stock,  such  notice  to be  addressed  to each such  holder at his post  office
address as shown by the records of the Corporation.

         A  consolidation  or merger of the  Corporation  with or into any other
entity or entities, or a sale, transfer, exchange or other disposition of all or
substantially all of the assets of the Corporation, shall not be deemed, for the
purposes of this Section 4, to be a liquidation,  dissolution,  or winding up of
the  Corporation  and such  holders  shall  deliver  their  shares  of  Series B
Cumulative  Convertible  Preferred  Stock to the Corporation in exchange for the
distribution to be made.

         5. Optional Conversion. Any or all of the shares of Series B Cumulative
Convertible  Preferred  Stock shall be  convertible at any time and from time to
time,  at the  option of each  holder of record  thereof,  into  fully  paid and
nonassessable  shares of Class A Common Stock of the Corporation  upon surrender
to the Corporation of the certificate or certificates  representing the Series B
Cumulative Convertible Preferred Stock to be converted; and, upon receipt by the
Corporation of such surrendered certificate or certificates with any appropriate
endorsement thereon as may be prescribed by the Board of Directors,  such holder
shall be entitled to receive a  certificate  or  certificates  representing  the
shares of Class A Common  Stock into which  such  shares of Series B  Cumulative
Convertible Preferred Stock are convertible.  Such conversion shall be deemed to
have been made  immediately  prior to the close of  business on the date of such
surrender of the shares of Series B Cumulative Convertible Preferred Stock to be
converted,  and the person or persons  entitled to receive the shares of Class A
Common Stock issuable upon such conversion  shall be treated for all purposed as
the record  holder or holders of such shares of Class A Common  Stock as of such
date. The basis for such conversion shall be the "conversion  rate" in effect at
the time of conversion,  which for the purposes  hereof shall mean the number of
shares of Class A Common  Stock  issuable  for each share of Series B Cumulative
Convertible  Preferred Stock surrendered for conversion.  For the calendar years
1997 through 1999, the conversion  rate shall be 1 share of Class A Common Stock
for each 1.2 shares of Series B  Cumulative  Convertible  Preferred  Stock being
converted;  Thereafter,  the conversion  rate shall be 1 share of Class A Common
Stock issuable for each 1.3 shares of

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Series B Cumulative  Convertible  Preferred Stock and such conversion rate shall
be subject to  adjustment  as provided in Section 8 below.  In  connection  with
effecting  any  transfer to the  Corporation  for  cancellation  of any Series B
Cumulative  Convertible Preferred Stock upon conversion of the same into Class A
Common  Stock,  if any  fractional  interest in a share of Class A Common  Stock
would be  deliverable  upon such  conversion of Series B Cumulative  Convertible
Preferred Stock,  the Corporation  shall pay in lieu of such fractional share an
amount equal to the "conversion price" (as defined in the following sentence) of
such  fractional  share  (computed to the nearest one  thousandth of a share) in
effect at the close of business on the date of conversion.  As used herein,  the
term  "conversion  price" shall be an amount  computed by dividing  $5.00 by the
conversion rate then in effect. During the calendar years 1997 through 1999, the
conversion price shall be $6.00 per share; thereafter the conversion price shall
be $6.50 per share. The Board of Directors of the Corporation shall at all times
reserve a sufficient  number of authorized but unissued shares of Class A Common
Stock,  which shall be issued only in satisfaction of the conversion  rights and
privileges  aforesaid.  Any shares of Series B Cumulative  Convertible Preferred
Stock which have been converted shall be canceled and not reissued.

         6. Issue Taxes.  The Corporation  shall pay all issue taxes (other than
any taxes  measured  by the  income  of any  person  or  entity  other  than the
Corporation),  if any,  incurred  in  respect  of the issue of shares of Class A
Common Stock on  conversion.  If a holder of shares  surrendered  for conversion
specifies that the shares of Class A Common Stock to be issued on conversion are
to be  issued  in a name or names  other  than  the name or names in which  such
surrendered  shares  stand,  the  Corporation  shall not be  required to pay any
transfer  or other taxes  incurred  by reason of the  issuance of such shares of
Class A Common  Stock to the name of another,  and if the  appropriate  transfer
taxes shall not have been paid to the  Corporation or the transfer agent for the
Series B Cumulative  Convertible Preferred Stock at the time of surrender of the
shares  involved,  the shares of Class A Common  Stock  issued  upon  conversion
thereof may be registered in the name or names in which the  surrendered  shares
were registered, despite the instructions to the contrary.

         7. Redemption at the Option of  Corporation.  (a) If the Class A Common
Stock of the  Corporation  trades for 30 consecutive  trading days at a price of
$9.00 per share or more and the average daily trading volume of the shares is at
least 5,000 shares,  the  Corporation  may, upon written Notice of Redemption as
provided below, redeem shares of Series B Cumulative Convertible Preferred Stock
out of funds legally available therefore, at the option of the Corporation, as a
whole, or from time to time, in part for cash at the "Redemption Price". If less
than all the  outstanding  shares of Series B Cumulative  Convertible  Preferred
Stock are to be  redeemed,  the shares to be  redeemed  shall be selected by the
Corporation  and shall be either (i) selected by lot in such manner as the Board
of  Directors  may  determine,  or (ii) a pro-rata  proportion  of the shares of
Series B  Cumulative  Convertible  Preferred  Stock of all  holders  of Series B
Cumulative Convertible Preferred Stock.

                  (b) If full  cumulative  dividends  on the Series B Cumulative
Convertible  Preferred  Stock  have  not been  paid,  the  Series  B  Cumulative
Convertible  Preferred Stock may not be redeemed in part and the Corporation may
not  purchase  or  acquire  any shares of the  Series B  Cumulative  Convertible
Preferred  Stock otherwise than pursuant to a purchase or exchange offer made on
the same  terms to all  holders  of Series B  Cumulative  Convertible  Preferred
Stock.

                  (c) If a Notice  of  Redemption  has been  given  pursuant  to
Section 7(d) and if, on or before the Redemption  Date, the funds  necessary for
such redemption shall have been set aside by the Corporation, separate and apart
from its other  funds,  in trust for the pro rata  benefit of the holders of the
shares so called for redemption, then, notwithstanding that any certificates for
such shares have not been surrendered for  cancellation,  on the Redemption Date
dividends shall cease to accrue on the shares of

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Series B Cumulative Convertible Preferred Stock to be redeemed, and at the close
of business on the Redemption  Date the holders of such shares shall cease to be
stockholders with respect to such shares and shall have no interest in or claims
against  the  Corporation  by virtue  thereof  and shall have no voting or other
rights with respect to such shares,  except the rights to receive moneys payable
upon such redemption, without interest thereon, upon surrender (and endorsement,
if required by the Corporation) of their certificates,  and the shares evidenced
thereby shall no longer be outstanding.

                  (d)  Not  less  than 30 nor  more  than  60  days  before  any
Redemption Date,  written Notice of Redemption  shall be given by mail,  postage
prepaid, to holders of record of the Series B Cumulative  Convertible  Preferred
Stock,  such notice to be addressed to each such  stockholder at his post office
address as shown by the  records of the  Corporation,  specifying  the number of
shares  to be  redeemed,  the  Redemption  Price  and the date and place of such
redemption.

                  (e) The Series B Cumulative  Convertible Preferred Stock to be
redeemed on the  Redemption  Date shall be redeemed by making a Cash Payment Per
Share as  presented  in the  table  below  plus an  amount  equal to all  unpaid
dividends  which  have  been  earned  on the  outstanding  shares  of  Series  B
Cumulative  Convertible  Preferred  Stock  prior to the  Redemption  Date,  such
amounts being herein sometimes referred to as the "Redemption Price."

         For  Redemption  Dates prior to December 31, 1999, the Cash Payment Per
         Share is $7.50.

         For  Redemption  Dates  subsequent  to  December  31, 1999 and prior to
         December 31, 2000, the Cash Payment Per Share is $9.00.

         For Redemption  Dates subsequent to December 31, 2000, the Cash Payment
         Per Share is $12.00.

                  (f) Each holder of  outstanding  shares of Series B Cumulative
Convertible  Preferred Stock called for redemption may convert those shares into
Class A Common  Stock as  provided  herein at any time  prior to the  Redemption
Date.

         8. Adjustment of Conversion  Price and Conversion  Rate. The number and
kind of  securities  issuable  upon the  conversion  of the Series B  Cumulative
Convertible  Preferred Stock, the conversion price and the conversion rate shall
be subject to adjustment  from time to time upon the happening of certain events
as follows:

                  (a)  Reorganization,  Reclassification.  In  the  event  of  a
reorganization, share exchange, or reclassification,  other than a change in par
value,  or  from  no par  value  to par  value  or a  transaction  described  in
subsection  (b) or (c)  below,  each  share of Series B  Cumulative  Convertible
Preferred   Stock  shall,   after  such   reorganization,   share   exchange  or
reclassification,  be convertible into the kind and number of shares of stock or
other  securities or property of the Corporation to which the holder of Series B
Cumulative  Convertible  Preferred  Stock would have been entitled if the holder
had held the Class A Common  Stock  issuable  upon  conversion  of his  Series B
Cumulative Convertible Preferred Stock immediately prior to such reorganization,
share exchange, or reclassification.

                  (b)  Consolidation,   Sale  or  Merger.  In  the  event  of  a
consolidation, sale or merger to which the Corporation is a party, each share of
Series B Cumulative  Convertible Preferred Stock shall after such consolidation,
sale or  merger,  be  convertible  into the kind and  number  of shares of stock
and/or  other  securities,  cash or other  property  to which the holder of such
share of  Series B  Cumulative  Convertible  Preferred  Stock  would  have  been
entitled  if the  holder  had  held  the  Class A  Common  Stock  issuable  upon
conversion  of his  share of Series B  Cumulative  Convertible  Preferred  Stock
immediately prior to such consolidation, sale or merger.

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                  In  the  event  that  the  holders  of  Series  B   Cumulative
Convertible Preferred Stock determine that the security proposed to be issued in
a  consolidation,  sale or merger is materially less favorable than the value of
the Preferred Stock acquired  herein,  the sole remedy of the holder shall be to
force the  Corporation  to redeem the holder's  Series B Cumulative  Convertible
Preferred Stock at a redemption  price equal to $7.50 in cash. Any dispute as to
whether the  security to be issued to the holder is  materially  less  favorable
than the  holder's  Series B  Cumulative  Convertible  Preferred  Stock shall be
settled by arbitration in accordance  with Commercial  Arbitration  Rules of the
American Arbitration  Association now in effect (the "AAA Rules"),  conducted by
one  arbitrator  either  mutually  agreed  upon  by the  parties  or  chosen  in
accordance with AAA Rules. Costs and expenses of the arbitrator shall be divided
equally  between  the  parties.   Reasonable   attorneys  fees  related  to  the
arbitration  shall be borne as determined by the  arbitrator.  Judgment upon the
awarded  rendered  by  the  arbitrator  may  be  entered  in  any  court  having
jurisdiction thereof.

                  (c) Subdivision or Combination of Shares.  In case outstanding
shares of Class A Common Stock shall be subdivided or combined,  the  conversion
price shall be proportionately  reduced,  in case of subdivision of such shares,
as of the  effective  date of such  subdivision,  or as of the date a record  is
taken of the holders of Class A Common Stock for the purpose of so  subdividing,
whichever  is  earlier,  or  shall  be  proportionately  increased,  in  case of
combination of such shares, as of the effective date of such combination,  or as
of the date a record  is taken of the  holders  of Class A Common  Stock for the
purpose of so combining, whichever is earlier.

                  (d) Stock  Dividends.  In case shares of Class A Common  Stock
are issued as a dividend or other distribution on the Class A Common Stock, then
the conversion price shall be adjusted,  as of the date a record is taken of the
holders of Class A Common  Stock for the purpose of receiving  such  dividend or
other  distribution  (or if no such  record  is  taken,  as at the  date of such
payment or other  distribution),  to that price  determined by  multiplying  the
conversion  price  in  effect   immediately  prior  to  such  payment  or  other
distribution  by a fraction  (i) the  numerator  of which shall be the number of
shares of Class A Common Stock outstanding immediately prior to such dividend or
other distribution,  and (ii) the denominator of which shall be the total number
of shares of Class A Common Stock outstanding immediately after such dividend or
other distribution.

                  (e) Adjustment of Conversion Rate. Upon each adjustment of the
conversion  price under the  provisions of this Section 8, the  conversion  rate
shall be adjusted to an amount  determined  by dividing  $5.00 by such  adjusted
conversion  price so that  the  product  of (w) the  adjusted  conversion  price
multiplied  by (x) the  number  of shares of Common  Stock  then  issuable  upon
conversion shall equal the product of (y) the conversion price immediately prior
to the adjustment of conversion  price multiplied by (z) the number of shares of
Common Stock issuable upon conversion immediately prior to the event giving rise
to such adjustment.

                  (f) Other  Provisions  Applicable  to  Adjustments  Under this
Section.   The  following  provisions  will  be  applicable  to  the  making  of
adjustments in conversion price hereinabove provided in this Section 8.

                           (i)  Treasury Shares. The number of shares of  Common
Stock  at  any time  outstanding  shall  not include  any  shares  thereof  then
directly or indirectly owned or held by or for the account of the corporation.

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                           (ii)  Certain  Definitions.   For  purposes  of  this
Section 8:

                                    (a) The term "Common  Stock" shall be deemed
to mean (i) the Class A Common Stock, no par value,  and (ii) The Class B Common
Stock,  no par value and (iii) the stock of the  corporation  of any  class,  or
series within a class, whether now or hereafter authorized,  which has the right
to  participate  in  the  distribution  of  either  earnings  or  assets  of the
Corporation without limit as to the amount or percentage.

                           (iii)   Minimum  Adjustment.  No  reduction  of   the
conversion  price  shall  be  made  if the amount of any such reduction would be
an amount  less than $.05,  but any such  amount  shall be carried  forward  and
reduction  with respect  thereof  shall be made at the time of and together with
any subsequent  reduction which,  together with such amount and any other amount
or amounts so carried forward, shall aggregate $.01 or more.

                  (g) Notices of  Adjustments.  Whenever the conversion rate and
conversion price is adjusted as herein  provided,  an officer of the Corporation
shall compute the adjusted  conversion  rate and conversion  price in accordance
with the foregoing  provisions  and shall prepare a written  instrument  setting
forth such adjusted  conversion rate and conversion  price and showing in detail
the facts upon which such adjustment is based, and such written instrument shall
promptly  be  delivered  to the  record  holders  of  the  Series  B  Cumulative
Convertible Preferred Stock.

         9. Notices of Record Dates and  Effective  Dates.  In case at any time:
(a) the Corporation shall declare a dividend (or any other  distribution) on the
Common  Stock  payable  otherwise  than in shares of  Common  Stock;  or (b) the
Corporation  shall  authorize  the  granting to the  holders of Common  Stock of
rights to subscribe  for or purchase any shares of capital stock of any class or
any  other   rights;   or  (c)  of  any   reorganization,   share   exchange  or
reclassification  of  the  capital  stock  of  the  Corporation  (other  than  a
subdivision or combination  of  outstanding  shares of Common Stock),  or of any
consolidation  or merger to which the Corporation is party or of the sale, lease
or exchange of all or substantially  all of the property of the Corporation;  or
(d) of the voluntary or  involuntary  dissolution,  liquidation or winding up of
the  Corporation,  then the  Corporation  shall cause to be mailed to the record
holders of the Series B  Convertible  Preferred  Stock at least twenty (20) days
prior to the applicable record date or effective date hereinafter  specified,  a
notice  stating (i) the date on which a record is to be taken for the purpose of
such dividend,  distribution or rights,  or, if a record is not to be taken, the
date as of which the  holders of record of Common  Stock to be  entitled to such
dividend,  distribution or rights are to be determined or (ii) the date of which
such reclassification,  reorganization,  share exchange, consolidation,  merger,
sale, lease,  exchange,  dissolution,  liquidation or winding up, is expected to
become effective, and the date as of which it is expected that holders of record
of Common  Stock shall be entitled to exchange  their shares of Common Stock for
securities   or  other   property   deliverable   upon  such   reclassification,
reorganization, share exchange, consolidation, liquidation, merger, sale, lease,
exchange, dissolution or winding up.

         10. Voting Rights.

                  (a) Holders of Series B Cumulative Convertible Preferred Stock
shall be entitled to notice of any  stockholders'  meeting.  Except as otherwise
provided  herein or  required  by law,  at any annual or special  meeting of the
Corporation's stockholders, or in connection with any written consent in lieu of
any such  meeting,  each  outstanding  share of Series B Cumulative  Convertible
Preferred  Stock shall be entitled to the number of votes equal to the number of
full shares of Class A Common Stock into which such share of Series B Cumulative
Convertible  Preferred  Stock is then  convertible  (calculated  by rounding any
fractional  share down to the nearest whole  number).  Initially,  each share of
Series B Cumulative

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Convertible  Preferred Stock shall have one vote.  Except as otherwise  required
herein or by law, the Series B Cumulative  Convertible  Preferred  Stock and the
Class A Common  Stock  shall  vote  together  on each  matter  submitted  to the
stockholders, and not by separate class or series.

                  (b)  For  as  long  as  any  shares  of  Series  B  Cumulative
Convertible Preferred Stock are outstanding, then, in addition to any other vote
or consent of stockholders  provided by law or by the Corporation's  Certificate
of  Incorporation,  the affirmative  vote or written consent of the holders of a
majority  of  the  Series  B  Cumulative   Convertible   Preferred   Stock  then
outstanding,  voting as a separate  class,  shall be  necessary  or effective to
validate:

                           (i)  any  amendment,  alteration  or  repeal  of  any
provision of, or addition of any provision to, the Corporation's  Certificate of
Incorporation,  in the event that such action  would alter or change the powers,
preferences or special rights of the Series B Cumulative  Convertible  Preferred
Stock; or

                           (ii)  the   authorization  of  the  increase  in  the
authorized amount of shares of Series B Cumulative  Convertible Preferred Stock,
or the creation of, or the increase in the  authorized  amount of, any shares of
any class or series,  or any  security  convertible  into shares of any class or
series,  ranking  senior  to  or  on a  parity  with  the  Series  B  Cumulative
Convertible Preferred Stock in the distribution of assets on liquidation,  or in
the payment of dividends or otherwise.

                  The foregoing amendment to the Certificate of Incorporation of
the  Corporation  was adopted by the Board of  Directors of the  Corporation  on
February 7, 1997 in the manner prescribed by the New Jersey Business Corporation
Act.

                  IN  WITNESS   WHEREOF,   the   Corporation   has  caused  this
Certificate to be executed on its behalf by its President as of this 27th day of
February, 1997.


                                             ECHOCATH, INC.


                                             By:
                                                 -----------------------------
                                                 Frank DeBernardis, President


                                      - 7 -


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