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                                                                   EXHIBIT 10.22

                                SECOND AMENDMENT
                                       TO
                               OPERATING AGREEMENT
                                       OF
                           HEART HOSPITAL OF DTO, LLC

         This SECOND AMENDMENT (the "Second Amendment") is entered into as of
this 27th day of July, 1998, by and among HEART HOSPITAL OF DTO, LLC, a North
Carolina limited liability company (the "Company"); DTO MANAGEMENT, INC., a
North Carolina corporation ("DTO Management"); each of the Investor Members (as
defined in the Original Operating Agreement of the Company); FRANCISCAN HEALTH
SYSTEM OF THE OHIO VALLEY, INC., an Ohio non-profit corporation ("FHS"); and
PROWELLNESS HEALTH MANAGEMENT SYSTEMS, INC., an Ohio corporation
("ProWellness").

                                    Preamble

         A.       On or about April 18, 1997, DTO Management and certain
Investor Members formed the Company in accordance with the original Operating
Agreement of Heart Hospital of DTO, LLC (the "Original Agreement").

         B.       In December of 1997, FHS and the other Members of the Company
executed a First Amendment to Operating Agreement (the "First Amendment") in
which FHS was admitted as a Member of the Company.

         C.       FHS, which is a "not-for-profit" corporation, owns a thirty
percent (30%) Membership Interest in the Company (the "Membership Interest") and
FHS desires to assign its Membership Interest to a wholly owned "for profit"
subsidiary known as ProWellness and ProWellness desires to become a Substitute
Member. In consideration of this assignment, ProWellness has agreed to: (1) pay
to FHS the amount of One Million Two Hundred Sixty Thousand Dollars ($1,260,000)
(which is the amount FHS previously contributed to the Company in exchange for
its Membership Interest); and (2) assume all of the rights, liabilities and
obligations of FHS as a Substitute Member in the Company, including but not
limited to the obligations to: (a) pay a "Maximum Mandatory Additional Capital
Contribution" of Two Million Five Hundred Twenty Thousand Dollars ($2,520,000),
as provided in Section 1(aa) of the First Amendment; and (b) provide guarantees
of or collateral for indebtedness of the Company, as provided in Section 1(g) of
the First Amendment (collectively, the "Assignment Consideration").

         D.       The requirements for assignment of a Member's Membership
Interest to a Substitute Member are set out in Sections 8.4, 8.5, and 8.6 of the
Original Agreement (the "Transfer Requirements").

         E.       The Members have entered into this Second Amendment for the
purpose of complying with those Transfer Requirements and to make certain
additional related changes to the Operating Agreement.


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                                    Amendment

         In consideration of their mutual rights and obligations and for other
good and valuable consideration, the parties amend and modify the Original
Agreement and the First Amendment as follows:

         1.       Defined Terms. All capitalized terms used in this Second
Amendment shall have the meanings assigned at their first use or, if none, then
the definitions assigned in the Original Agreement and/or the First Amendment.
The term "Operating Agreement" means the Original Agreement as modified by the
First Amendment and this Second Amendment.

         2.       Acknowledgment, Waiver and Consent. The Company and each of
the other Members of the Company acknowledge, waive and consent as follows: (a)
they have the right, but not the obligation, to purchase all (but not less than
all) of the Membership Interest of FHS for the Assignment Consideration; (b)
they waive and relinquish the right to purchase the Membership Interest of FHS;
(c) they consent to the assignment of the Membership Interest of FHS to
ProWellness; and (d) they consent to the admission of ProWellness as a
Substitute Member in the Company.

         3.       Assignment. FHS and ProWellness have agreed to execute and
acknowledge an Assignment of Membership Interest in the form attached to this
Second Amendment as Exhibit A (the "Assignment Document"), and DTO Management
approves and accepts the form of the Assignment ProWellness represents to the
Company that it meets the investor suitability standards established by the
State of Ohio (if any) and by the Company, as required by Section 8.4 of the
Original Agreement and that ProWellness will perform the obligations it has
assumed to the Company as part of the Assignment Consideration.

         4.       Continuing Liabilities and Obligations of FHS. In
consideration of, and as a material inducement to, the consents granted by the
Company and its Members, including DTO Management, FHS agrees to: (a) continue
to be directly and fully obligated and liable, jointly and severally with
ProWellness, under Sections 2.3(b), 3.5, 3.7, 3.8, 5.9 and Exhibit A of the
Operating Agreement; and (b) provide guarantees of or collateral security for
all guarantees furnished by ProWellness to the Company and/or to its lenders or
lessors, to the same extent originally contemplated by Section 1(g) of the First
Amendment.

         5.       Admission as Substitute Member. DTO Management acknowledges
that ProWellness has fulfilled the conditions set out in Section 8.6 of the
Original Agreement. Therefore, effective on the date of this Second Amendment
and the execution and delivery of the Assignment Document, FHS shall cease to be
a Member of the Company and ProWellness is admitted as a Substitute Member in
the Company with all rights and privileges previously accorded to FHS.

         6.       Appointment of Investor Manager. The Investor Members
acknowledge that they have elected Hans Zwart, M.D. to serve as their initial
Investor Manager, as provided in Section 5.13(a) of the Operating Agreement.
ProWellness acknowledges that is has designated Duane L.


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Erwin to serve as its initial Investor Manager, as provided in Section 5.13(b)
of the Operating Agreement. These Investor Managers shall serve for the terms
provided in the Operating Agreement and each of them may be replaced as provided
in the Operating Agreement.

         7.       Amendments to the First Amendment. The First Amendment is
modified and amended as follows:

         (a)      Substitution of ProWellness. Subject to the terms of this
Second Amendment, each reference to FHS in the First Amendment shall be
construed and interpreted to refer to ProWellness (unless the context implies a
reference to an Affiliate of ProWellness).

         (b)      Deletion of Recision Rights. Sections 4 and 5 of the First
Amendment are deleted in their entirety, so that neither DTO Management, nor
FHS, nor ProWellness may rescind the Operating Agreement or terminate the
interest of ProWellness in the Company for the reasons stated in those Sections
4 and 5.

         (c)      Correction of Typographical Error. Section 1(z) of the First
Amendment is corrected to refer to the fifth sentence of Section 11.1(g) (not
11.2(g)) of the Original Agreement.

         8.       Admission of Additional Investor Member. Mercy Health System -
Western Ohio ("Mercy Hospital") has expressed a desire to become an investor and
Member of the Company. FHS, ProWellness and the undersigned Investor Members
authorize DTO Management to execute and deliver any documents reasonably
necessary to permit Mercy Hospital to subscribe for ten (10) Units in the
Company and to admit Mercy Hospital as a Member of the Company. In exchange for
the subscription from Mercy Hospital, Mercy Hospital shall be exempted from
complying with the restrictive covenants of Section 5.9(b) of the Operating
Agreement, so long as Mercy Hospital complies with the following restrictions:

         Section 5.9(b) of the Operating Agreement shall be applicable to Mercy
Hospital in its entirety except that for purposes of Mercy Hospital only, the
references in Section 5.9(b) to "fifty (50)" miles shall be deleted and "ten
(10)" miles shall be substituted in lieu thereof.

         9.       Interpretation. To the extent possible, this Second Amendment
shall be construed so as to be consistent with the Original Agreement and the
First Amendment. However, if there is any discrepancy between any provision of
this Second Amendment and any provision of the Original Agreement or the First
Amendment, then this Second Amendment shall be construed to control.

         10.      No Further Change. All other terms and conditions of the
Original Agreement and the First Amendment remain unmodified and in full force
and effect.

         11.      Counterparts and Facsimiles. This Second Amendment may be
executed in any number of counterparts which may be signed by original or
facsimiles of original signatures, all of which, taken together, shall
constitute a single enforceable agreement.


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         12.      Effective Date. In compliance with the requirements of Section
11.2 of the Operating Agreement, this Second Amendment shall not become
effective as to all Members of the Company until it has been approved and signed
by DTO Management, FHS, ProWellness and a Majority Vote of the Investor Members,
at which point it shall be construed to be retroactively effective as of July
27, 1998.

         IN WITNESS WHEREOF, the parties have executed this Amendment effective
as of the day and year first above written.


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