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                                                                   Exhibit 10.16

                               AMENDMENT TO LEASE

     THIS AMENDMENT (the "Amendment"), dated as of the 28th day of February,
2001, between Universal Health Realty Income Trust ("Lessor"), a Maryland real
estate investment trust having an address at 367 South Gulph Road, King of
Prussia, Pennsylvania 19406, and McAllen Hospitals, L.P. ("Lessee"), a Delaware
limited partnership having an address at 367 South Gulph Road, King of Prussia,
Pennsylvania 19406, which is a subsidiary of Universal Health Services, Inc., a
Delaware corporation.

                              W I T N E S S E T H
                              - - - - - - - - - -

     WHEREAS, by Lease, dated as of December 24, 1986, as the same heretofore
has been amended (said Lease, as amended, is hereinafter referred to as the
"Lease"), certain premises (the "Leased Property"), as therein described, are
now leased and demised by Lessor to Lessee, as successor by merger to McAllen
Medical Center, L.P. (f/k/a Universal Health Services of McAllen, Inc.); and

     WHEREAS, Lessee also has an interest in that certain facility in McAllen,
Texas, commonly referred to as McAllen Medical Heart Hospital (the "Heart
Hospital"); and

     WHEREAS, for operational, administrative, reimbursement and other purposes,
Lessee desires to combine the operations of the Heart Hospital and the Leased
Property for bookkeeping purposes, and as a result of such combination, the
accounts will not distinguish between gross revenues generated by the Leased
Property and gross revenues generated by the Heart Hospital; and

     WHEREAS, Lessee has requested that Lessor modify certain provisions of the
Lease and Lessor has agreed to do so subject to and in accordance with the terms
and provisions of this Amendment; and

     WHEREAS, the parties hereto mutually desire to amend the Lease as herein
set forth, and are executing and delivering this Amendment for such purpose;

     NOW, THEREFORE, the parties hereto, in consideration of the terms and
conditions herein contained and other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, hereby amend the Lease
as follows.

     1.   Amendment. Notwithstanding anything to the contrary contained in the
Lease, effective on and after February 28, 2001,

          (a) the defined term "Excess Gross Revenues" in Article II of the
     Master Lease shall be restated in its entirety to read as follows:

          "Excess Gross Revenues:  The amount by which (i) (y) with respect to
           ---------------------
          any measuring period to the extent occurring prior to February 28,
          2001, One Hundred (100%) percent of Gross Revenues for such measuring
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          period and (z) with respect to any measuring period to the extent
          occurring on or after February 28, 2001, Eighty-four point four
          (84.4%) percent of Gross Revenues for such measuring period exceeds
          (ii) the Gross Revenues for the equivalent period of the Base Year."

          (b) for the purpose of determining Gross Revenues with respect to any
     measuring period to the extent occurring on or after February 28, 2001 and
     not encompassing all or any portion of the Base Year, the defined term
     "Gross Revenues" in Article II of the Master Lease is amended by adding the
     words "and the Heart Hospital" immediately after "Leased Property" in all
     instances where the term "Leased Property" occurs in the first sentence of
     the first paragraph thereof.

          (c) for the purpose of determining Gross Revenues with respect to any
     measuring period to the extent occurring on or after February 28, 2001 and
     not encompassing all or any portion of the Base Year, the defined term
     "Gross Revenues" in Article II of the Master Lease is amended by adding the
     words "or the Heart Hospital" immediately after "Leased Property" in all
     instances where the term "Leased Property" occurs in the first sentence of
     the second paragraph thereof.

     2.   Brokerage. Lessee represents that it has not dealt with a broker or
finder in connection with this Amendment. Lessee shall indemnify, defend (with
legal counsel reasonably acceptable to Lessor) and save harmless Lessor from and
against all liability, claims, suits, demands, judgments, costs, interest and
expenses (including, without limitation, reasonable counsel fees and
disbursements incurred in the defense thereof) to which Lessor may be subject or
suffer by reason of any claim made for any commission, reimbursement or other
compensation arising from or as a result of the execution and delivery of this
Amendment.

     3.   Full Force and Effect. The Lease, as hereby amended, shall remain in
full force and effect according to its terms and conditions.

     4.   Defined Terms. All terms used but not defined in this Amendment shall,
for the purposes hereof, have the respective meanings ascribed to such terms in
the Lease.

     5.   Successors and Assigns. The covenants, agreements, terms and
conditions contained in this Amendment shall bind and inure to the benefit of
the parties hereto and their respective successors and assigns.

     6.   Amendments in Writing. This Amendment may not be changed orally, but
only by a writing signed by the party against whom enforcement thereof is
sought.

     7.   Effectiveness. This Amendment shall not be binding in any respect upon
Lessor until a counterpart hereof is executed by Lessor and delivered to Lessee.

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

                                 UNIVERSAL HEALTH REALTY INCOME TRUST


                                 By:____________________________________
                                     Name: Cheryl K. Ramagano
                                     Title: Vice President



                                 McALLEN HOSPITALS, LP
                                 By: South Texas Heart, Inc.,
                                     general partner


                                 By:____________________________________
                                     Name: Steve Filton
                                     Title: Vice President

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