Document:

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                                                                   EXHIBIT 10.21

                 FIRST AMENDMENT TO LOAN AND SECURITY AGREEMENT

         This First Amendment to Loan and Security Agreement (the "First
Amendment") is made as of this 23rd of August, 2002 by and among

         Fleet Retail Finance Inc. (the "Agent"), a Delaware corporation with
its principal executive offices at 40 Broad Street, Boston, Massachusetts, for
the Revolving Credit Lenders party to the Agreement (defined below), and

         The CIT Group/Business Credit, Inc. (the "Co-Agent"), a New York
corporation with offices at 5420 LBJ Freeway (Suite 200), Dallas, Texas, and

         The Revolving Credit Lenders party to the Agreement, and

         Hastings Entertainment, Inc. (the "Borrower"), a Texas corporation with
its principal executive offices at 3601 Plains Boulevard, Amarillo, Texas 79102

in consideration of the mutual covenants herein contained and benefits to be
derived herefrom.

                                   WITNESSETH:

         WHEREAS, on August 29, 2000, the Agent, the Co-Agent, the Revolving
Credit Lenders and the Borrower entered in a certain Loan and Security Agreement
(as amended and in effect, the "Agreement"); and

         WHEREAS, the Agent, the Co-Agent, the Revolving Credit Lenders and the
Borrower desire to modify certain provisions of the Agreement as set forth
herein.

         NOW, THEREFORE, it is hereby agreed among the Agent, the Co-Agent, the
Revolving Credit Lenders and the Borrower as follows:

         1.       Capitalized Terms. All capitalized terms used herein and not
                  otherwise defined shall have the same meaning herein as in the
                  Agreement.

         2.       Amendments to Article 1. The provisions of Article 1 of the
                  Agreement are hereby amended as follows:

                  (a)      The definition of "Base Margin Rate" is hereby
                           deleted in its entirety, and the following
                           substituted in its stead:

                           "BASE MARGIN RATE": That rate per annum which is the
                           aggregate of Base plus the Base Margin.

                  (b)      The definition of "Libor Margin" is hereby deleted in
                           its entirety, and the following substituted in its
                           stead:

                           "LIBOR MARGIN": Shall mean as of the effective date
                           of the First Amendment, 2.0% (notwithstanding that
                           Average Availability requirements for another Level
                           may have been satisfied). Thereafter, commencing May
                           1, 2003, and on the first day of each calendar
                           quarter thereafter, the Libor Margin shall be
                           adjusted based upon the Borrower's aggregate daily
                           Average Availability for the immediately

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                           preceding calendar quarter divided by the total
                           number of days in such immediately preceding calendar
                           quarter. Provided, however, upon the occurrence of an
                           Event of Default, the Libor Margin shall be
                           immediately increased to the percentage set forth in
                           Level IV below (even if the Average Availability
                           requirements for another Level have been met), and
                           interest shall be determined in the manner set forth
                           in Section 2-11(f).

<Table>
<Caption>
  LEVEL                        AVERAGE AVAILABILITY                   LIBOR MARGIN
  -----                        --------------------                   ------------
<S>                  <C>                                              <C>
    I                        Greater than $50,000,000                     1.75%
   II                Greater than $35,000,000 and less than               2.00%
                             or equal to $50,000,000
  III                Greater than $25,000,000 and less than               2.25%
                             or equal to $35,000,000
   IV                 less than or equal to $25,000,000                   2.50%
</Table>

                  (c)      The definition of "Maturity Date" is hereby amended
                           by deleting the following therefrom:

                           AUGUST 29, 2003

                           and substituting the following in its stead:

                           AUGUST 29, 2005

                  (d)      The definition of "Revolving Credit Ceiling" is
                           hereby deleted in its entirety, and the following
                           substituted in its stead:

                           "REVOLVING CREDIT CEILING": $80,000,000.00.

                  (e)      The following new definitions are hereby added to the
                           Agreement:

                                    (i)      "BASE MARGIN": Shall mean as of the
                                             effective date of the First
                                             Amendment, 0.0% (notwithstanding
                                             that Average Availability
                                             requirements for another Level may
                                             have been satisfied). Thereafter,
                                             commencing May 1, 2003, and on the
                                             first day of each calendar quarter
                                             thereafter, the Base Margin shall
                                             be adjusted based upon the
                                             Borrower's aggregate daily Average
                                             Availability for the immediately
                                             preceding calendar quarter divided
                                             by the total number of days in such
                                             immediately preceding calendar
                                             quarter. Provided, however, upon
                                             the occurrence of an Event of
                                             Default, the Base Margin shall be
                                             immediately increased to the
                                             percentage set forth in Level IV
                                             below (even if the Average
                                             Availability requirements for
                                             another Level have

                                        2

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                                             been met), and interest shall be
                                             determined in the manner set forth
                                             in Section 2-11(f).

<Table>
<Caption>
  LEVEL             AVERAGE AVAILABILITY                BASE MARGIN
  -----             --------------------                -----------
<S>          <C>                                        <C>

     I             Greater than $50,000,000                   0.0%
    II       Greater than $35,000,000 and less than           0.0%
                    or equal to $50,000,000

   III       Greater than $25,000,000 and less than          0.25%
                    or equal to $35,000,000

    IV        less than or equal to $25,000,000              0.50%
</Table>

                                    (ii)     "FIRST AMENDMENT" Shall mean that
                                             certain First Amendment to Loan and
                                             Security Agreement dated August
                                             23rd by and among the Borrower, the
                                             Agent, and the Revolving Credit
                                             Lenders.

         3.       Amendments to Article 2. The provisions of Article 2 are
                  hereby amended as follows:

         (a)      Section 2-14 of the Agreement is hereby amended by deleting
                  the following from the fourth (4th) line thereof:

                  $70,000,000.00

                  and substituting the following in its stead:

                  $80,000,000.00

         (b)      Section 2-15 of the Agreement is hereby amended by deleting
                  the following from the third (3rd) line thereof:

                  February 28, 2002

                  and substituting the following in its stead:

                  February 28, 2004

                                       3

<PAGE>

         4.       Amendments to Exhibits.

                  (a)      Exhibit 2:2-22 is hereby deleted in its entirety, and
                           is replaced by Exhibit 2:2-22 annexed hereto and
                           incorporated herein by reference.

                  (b)      The remaining Exhibits to the Agreement are true and
                           accurate in all respects and there have been no
                           changes thereto from the date on which such Exhibits
                           were delivered to the Agent.

         5.       Amendment Fee. As compensation for the commitments of the
                  Revolving Credit Lenders to enter into this First Amendment
                  with the Borrower and to continue to make loans and advances
                  to the Borrower and as compensation for such Revolving Credit
                  Lenders' respective maintenance of sufficient funds available
                  for such purpose, such Revolving Credit Lenders have earned an
                  Amendment Fee (the "Amendment Fee") in the amount and which
                  shall be paid, in accordance with the terms and conditions of
                  the Amendment Fee Letter of even date herewith by and between
                  the Borrower and the Agent (the "Amendment Fee Letter"). The
                  Amendment Fee shall be deemed fully earned upon the execution
                  hereof and shall not be subject to refund or rebate under any
                  circumstances.

         6.       Ratification of Loan Documents. Except as provided herein, all
                  terms and conditions of the Agreement and the other Loan
                  Documents remain in full force and effect. The Borrower hereby
                  ratifies, confirms, and reaffirms all representations,
                  warranties, and covenants contained therein and hereby
                  represents that no Events of Default exist under the Loan
                  Documents. The Borrower further ratifies and confirms that any
                  and all Collateral previously granted to the Agent for the
                  ratable benefit of the Revolving Credit Lenders continues to
                  secure the existing Liabilities as well as the Liabilities as
                  amended hereby, and any future Liabilities.

         7.       Conditions to Effectiveness. This First Amendment shall
                  become effective upon the satisfaction of the following
                  conditions precedent:

                  (a)      This First Amendment shall have been duly executed
                           and delivered by each of the Borrower, the Revolving
                           Credit Lenders and the Agent and shall be in full
                           force and effect.

                  (b)      The Borrower shall have paid to the Agent, for the
                           ratable benefit of the Revolving Credit Lenders, the
                           Amendment Fee.

                  (c)      The Borrower shall have delivered to the Agent its
                           Secretary's Certificate with certified copies of (i)
                           Incumbency Certificate; (ii) Specimen Signatures; and
                           (iii) Resolutions.

                  (d)      All proceedings in connection with the transactions
                           contemplated by this First Amendment and all
                           documents incident thereto shall be reasonably
                           satisfactory in substance and form to the Agent, and
                           the Agent shall have

                                       4

<PAGE>

                           received all information and such counterpart
                           originals or certified or other copies of such
                           documents as the Agent may reasonably request.
                           Further, the Borrower shall have delivered to the
                           Agent such additional documents which the Agent may
                           reasonably request, including, without limitation, an
                           amended and restated Revolving Credit Note to reflect
                           the increase in the Revolving Credit Ceiling, the
                           Amendment Fee Letter, and a ratification by each
                           guarantor of their respective guaranties.

                  (e)      The Borrower shall have paid all reasonable costs and
                           expenses of the Agent including, without limitation,
                           all attorneys' fees and expenses incurred by the
                           Agent in connection with the Agreement, the Loan
                           Documents, and the preparation, negotiation and
                           execution of this First Amendment.

         8.       Miscellaneous.

                           (a) This First Amendment may be executed in several
                  counterparts and by each party on a separate counterpart, each
                  of which when so executed and delivered shall be an original,
                  and all of which together shall constitute one instrument.

                           (b) This First Amendment expresses the entire
                  understanding of the parties with respect to the transactions
                  contemplated hereby. No prior negotiations or discussions
                  shall limit, modify, or otherwise affect the provisions hereof

                           (c) Any determination that any provision of this
                  First Amendment or any application hereof is invalid, illegal
                  or unenforceable in any respect and in any instance shall not
                  effect the validity, legality, or enforceability of such
                  provision in any other instance, or the validity, legality or
                  enforceability of any other provisions of this First
                  Amendment.

                           (d) The Borrower shall pay on demand all costs and
                  expenses of the Agent, including, without limitation,
                  reasonable attorneys' fees in connection with the preparation,
                  negotiation, execution and delivery of this First Amendment.

                           (e) The Borrower warrants and represents that the
                  Borrower has consulted with independent legal counsel of the
                  Borrower's selection in connection with this First Amendment
                  and is not relying on any representations or warranties of any
                  Revolving Credit Lender or the Agent or their respective
                  counsel in entering into this First Amendment.

                           (f) The Borrower acknowledges and agrees that the
                  Borrower does not have any claims, counterclaims, offsets, or
                  defenses against any Revolving Credit Lender or the Agent
                  directly or indirectly relating to the Borrower's relationship
                  with, and/or the Borrower's Liabilities, and to the extent
                  that the Borrower has or ever had any such claims,
                  counterclaims, offsets, or defenses against any of the

                                       5

<PAGE>

                  Revolving Credit Lenders or the Agent, the Borrower
                  affirmatively WAIVES the same. The Borrower, and for its
                  representatives, successors and assigns, hereby RELEASES, and
                  forever discharges the Revolving Credit Lenders and the Agent
                  and their respective officers, directors, agents, servants,
                  attorneys, and employees, and their respective
                  representatives, successors and assigns, of, to, and from all
                  known debts, demands, actions, suits, accounts, covenants,
                  contracts, agreements, damages, and any and all claims,
                  demands, or liabilities whatsoever, of every name and nature,
                  both at law and in equity through the date hereof.

                  [remainder of page left intentionally blank]

                                       6

<PAGE>

         IN WITNESS WHEREOF, the parties have hereunto caused this First
Amendment to be executed and their seals to be hereto affixed as of the date
first above written.

                                       HASTINGS ENTERTAINMENT, INC.

                                                              ("Borrower")

                                       By:   /s/ DANNY CROW
                                           -------------------------------------
                                       Name:     Danny Crow
                                            ------------------------------------
                                       Title:    CFO
                                             -----------------------------------

                                       FLEET RETAIL FINANCE INC.
                                                                 ("Agent")

                                       By:   /s/ TIMOTHY R. TOBIN
                                           -------------------------------------
                                       Name:     Timothy R. Tobin
                                            ------------------------------------
                                       Title:    Director
                                             -----------------------------------

                                       THE CIT GROUP/BUSINESS CREDIT, INC.
                                                              ("Co-Agent")

                                       By:   /s/ ROBERT J. MOLLOY
                                           -------------------------------------
                                       Name:     Robert J. Molloy
                                            ------------------------------------
                                       Title:    Vice President
                                             -----------------------------------

                                       7

<PAGE>

                                       The "Revolving Credit Lenders"

                                       FLEET RETAIL FINANCE INC.

                                       By:   /s/ TIMOTHY R. TOBIN
                                           -------------------------------------
                                       Name:     Timothy R. Tobin
                                            ------------------------------------
                                       Title:    Director
                                             -----------------------------------

                                       THE CIT GROUP/BUSINESS CREDIT, INC.

                                       By:   /s/ ROBERT J. MOLLOY
                                           -------------------------------------
                                       Name:     Robert J. Molloy
                                            ------------------------------------
                                       Title:    Vice President
                                             -----------------------------------

                                       8

<PAGE>

                                 EXHIBIT 2:2-22

                     REVOLVING CREDIT LENDERS' COMMITMENTS

<Table>
<Caption>
                                             REVOLVING CREDIT                 REVOLVING CREDIT
REVOLVING CREDIT LENDER                      DOLLAR COMMITMENT                COMMITMENT PERCENTAGE
-----------------------                      -----------------                ---------------------
<S>                                          <C>                              <C>
Fleet Retail Finance Inc.                    $40,000,000.00                   50%
The CIT Group/Business Credit, Inc.          $40,000,000.00                   50%
                                             --------------                   --
Totals                                       $80,000,000.00                   100.000%
                                             ==============                   =======
</Table>

                                       9<PAGE>

                                                                     EXHIBIT 4.1

                                 AMENDMENT NO. 4
                                     TO THE
                               REDEEMABLE CLASS A
                                WARRANT AGREEMENT

         This Amendment No. 4 to the Warrant Agreement is dated as of September
11, 2002 by and between Hypertension Diagnostics, Inc., a Minnesota corporation
(the "Company"), and Mellon Investor Services LLC (the "Warrant Agent").

         A. The Company and U.S. Bank, N.A. (formerly known as Firstar Bank,
N.A., formerly known as Firstar Trust Company) have entered into that certain
Warrant Agreement dated as of July 23, 1998 (as from time to time heretofore or
hereafter amended, the "Class A Warrant Agreement") which governs the rights and
obligations of the Company and the Warrant Agent with respect to up to 2,587,500
Redeemable Class A Warrants (each, a "Class A Warrant").

         B. The Class A Warrant Agreement was amended by: (a) an Amendment No. 1
to Class A Warrant Agreement dated as of January 23, 2001 pursuant to which
Section 2.1 of the Class A Warrant Agreement was amended to reduce the exercise
price of the Warrants from $5.50 per share of Common Stock issuable upon
exercise of the Warrant to $5.15 per share of Common Stock issuable upon
exercise of the Warrant; (b) an Amendment No. 2 to Class A Warrant Agreement
dated as of June 6, 2002 pursuant to which Section 2.1 of the Class A Warrant
Agreement was amended to reduce the exercise price of the Warrants from $5.15
per share of Common Stock issuable upon exercise of the Warrant to $1.80 per
share of Common Stock issuable upon exercise of the Warrant and to extend the
expiration date of the Class A Warrant to August 7, 2002; and (c) an Amendment
No. 3 to the Class A Warrant Agreement pursuant to which the exercise price of
the Warrants was reduced from $1.80 per share of Common Stock issuable upon
exercise of the Warrant to $1.25 per share of Common Stock issuable upon
exercise of the Warrant and the expiration date of the Class A Warrant was
extended to September 17, 2002.

         C. The Company desires to extend the expiration date of the Class A
Warrant set forth in Section 2.1 of the Class A Warrant Agreement from September
17, 2002 to October 22, 2002.

         D. The parties desire to set forth their mutual understanding in this
Amendment No. 4 to the Class A Warrant Agreement.

         NOW, THEREFORE, in connection with and in consideration of the premises
and the mutual agreements and covenants hereinafter set forth, the Company and
the Warrant Agent hereby agree as follows:

<PAGE>

         1. Capitalized terms used but not otherwise defined herein shall have
the same meanings as in the Class A Warrant Agreement.

         2. The parties acknowledge that U.S. Bank, N.A. (formerly known as
Firstar Bank, N.A., formerly known as Firstar Trust Company), which heretofore
served as Warrant Agent, has resigned as Warrant Agent. The Company hereby
appoints Mellon Investor Services LLC as Warrant Agent, and Mellon Investor
Services LLC hereby accepts such appointment.

         3. Section 2.1 of the Class A Warrant Agreement is hereby amended to
read in its entirety as follows:

                  Section 2.1  Exercise. Any or all of the Warrants represented
         by each Warrant Certificate may be exercised by the holder thereof on
         or before 5:00 p.m., Central Time, on October 22, 2002, unless extended
         by the Company, by surrender of the Warrant Certificate with the
         Purchase Form, which is printed on the reverse thereof (or a reasonable
         facsimile thereof) duly executed by such holder, to the Warrant Agent
         at its principal office accompanied by payment, in cash or by certified
         or official bank check payable to the order of the Company, in an
         amount equal to the product of the number of shares of Common Stock
         issuable upon exercise of the Warrant represented by such Warrant
         Certificate, as adjusted pursuant to the provisions of Article III
         hereof, multiplied by the exercise price of $1.25, as adjusted pursuant
         to the provisions of Article III hereof (such price as so adjusted from
         time to time being herein called the "Exercise Price"), and such holder
         shall be entitled to receive such number of fully paid and
         nonassessable shares of Common Stock, as so adjusted, at the time of
         such exercise.

         4. The amendment to Section 2.1 as described in Paragraph 3 of this
Amendment No. 4 to the Class A Warrant Agreement shall take effect as of the
date hereof and continue until the expiration of the Warrant on October 22,
2002, unless this expiration date shall be extended by the Company. The Company
shall not extend such expiration date without the Warrant Agent's prior written
consent, in its sole discretion. Any purported extension without such consent of
the Warrant Agent shall be null and void.

         5. Except as expressly set forth in this Amendment No. 4, all terms of
the Class A Warrant Agreement shall remain in full force and effect until such
time as they may be amended in writing by the parties.

         6. Notwithstanding anything in the Class A Warrant Agreement or this
Amendment No. 4 to the contrary:

                  (a) the Company shall indemnify the Warrant Agent for, and
hold it harmless against, any loss, liability, claim or expense ("Loss") arising
out of or in connection with its duties under the Class A Warrant Agreement or
this Amendment No. 4 or its appointment as Warrant Agent, including the costs
and expenses of defending itself against any Loss or enforcing the Class A
Warrant Agreement or this Amendment, except to the extent that such Loss shall
have been determined by a court of competent jurisdiction to be a result of the
Warrant Agent's gross negligence or intentional misconduct.

                                       2

<PAGE>

                  (b) in the absence of gross negligence or intentional
misconduct on its part, the Warrant Agent shall not be liable for any action
taken, suffered or omitted by it or for any error of judgment made by it in the
performance of its duties under the Class A Warrant Agreement or this Amendment
No. 4. In no event will the Warrant Agent by liable for special, indirect,
incidental, consequential or punitive loss or damages of any kind whatsoever
(including but not limited to lost profits), even if the Warrant Agent has been
advised of the possibility of such damages. Any liability of the Warrant Agent
will be limited in the aggregate to an amount equal to the annual fee to be paid
by the Company to the Warrant Agent in connection with its appointment as
Warrant Agent.

         7. This Amendment No. 4 to the Class A Warrant Agreement shall be
construed and enforced in accordance with and governed by the laws of the State
of Minnesota, provided that the rights and obligations of the Warrant Agent
shall be enforced in accordance with and governed by the laws of the State of
New York.

         IN WITNESS WHEREOF, the parties hereto have executed this Amendment No.
4 to the Class A Warrant Agreement as of the day and year first above written.

                                        HYPERTENSION DIAGNOSTICS, INC.

                                        By: /s/ Greg H. Guettler
                                            ------------------------------------
                                            Greg H. Guettler
                                            Its:  President

                                        MELLON INVESTOR SERVICES LLC

                                        By: /s/  Kenneth Franke
                                            ------------------------------------
                                            Kenneth Franke
                                            Its:  Vice President

                                       3

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