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                                                                    Exhibit 99.1

AT THE COMPANY             AT THE FINANCIAL RELATIONS BOARD
--------------             --------------------------------
Thomas M. Tully            General Info:    Paula Schwartz
President & CEO            Analyst Info:    Brian Gill
(617)737-0930              Media Info:      Deanne Eagle
                           (212) 661-8030

FOR IMMEDIATE RELEASE
---------------------
May 27, 1999

                    NMT MEDICAL ADOPTS STOCKHOLDER RIGHTS PLAN
                    ------------------------------------------

Boston, MA, May 27, 1999 ---Nitinol Medical Technologies, Inc., (d/b/a "NMT
Medical") (Nasdaq/NMS:NMTI) announced today that its Board of Directors has
adopted a Stockholder Rights Plan in which preferred stock purchase rights will
be distributed on or about June 10, 1999 as a dividend at the rate of one Right
for each share of the Company's common stock outstanding as of the close of
business on June 10, 1999.

"The new Rights Plan is designed to allow all NMT Medical stockholders to
realize the long-term value of their investment in the Company and to protect
stockholders in the event of an unfair, coercive offer to acquire the Company,"
said Thomas M. Tully, President and Chief Executive Officer of NMT Medical.

According to Mr. Tully, the Board adopted the Rights Plan as a means of
deterring possible coercive or unfair takeover tactics and to prevent a
potential acquirer from gaining control of the Company without offering a fair
price to all of the Company's stockholders. "Coercive tactics can unfairly
pressure stockholders and squeeze them out of their investment without giving
them any real choice," said Mr. Tully. He added that the Company was not aware
of any unsolicited offer or takeover attempt. Mr. Tully also noted that similar
Rights Plans have been adopted by approximately 2,000 public companies.

Each Right will entitle NMT Medical stockholders to purchase one one-thousandth
of a share of a new series of junior participating preferred stock of the
Company at an exercise price of $20.00. The Rights will be exercisable if
another party acquires beneficial ownership of 15% (or, in the case of Whitney
Equity Partners, L.P. and its affiliates, which in the aggregate, currently hold
23.7% of the Company's outstanding common stock, 25%) or more of NMT Medical's
common stock, or upon the commencement of a tender or exchange offer that, if
consummated, would result in another party acquiring 15% (or, in the case of
Whitney Equity Partners, L.P. and its affiliates, 25%) or more of NMT Medical's
common stock (the "Acquiring Person").
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In the event of such an acquisition or similar event as described in the Rights
Plan, each Right, except those owned by the Acquiring Person, will enable the
holder of the Right to purchase that number of shares of NMT Medical common
stock which equals the exercise price of the Right divided by one-half of the
market price of such common stock.

In addition, if NMT Medical is involved in a merger or other transaction with
another company in which it is not the surviving corporation, or it sells or
transfers 50% or more of its assets or earning power to another company, each
Right will entitle its holder to purchase that number of shares of common stock
of the acquiring company which equals the exercise price of the Right divided by
one-half of the market price of such common stock.

The Company will be entitled to redeem the Rights at $0.001 per Right at any
time until the tenth business day following public announcement that a 15% stock
position (or, in the case of Whitney Equity Partners, L.P. and its affiliates, a
25% stock position) has been acquired or the commencement of a tender or
exchange offer that, if consummated, would result in another party acquiring 15%
(or, in the case of Whitney Equity Partners, L.P. and its affiliates, 25%) or
more of NMT Medical's common stock and in certain other circumstances. Unless
the Rights are redeemed or exchanged earlier, they will expire on June 9, 2009.

NMT Medical designs develops and markets innovative medical devices that utilize
advanced technologies and are delivered by minimally invasive procedures. The
Company's products are designed to offer alternative approaches to existing
complex treatments, thereby reducing patient trauma, shortening procedure,
hospitalization and recovery times, and lowering overall treatment costs. The
Company's medical devices include self-expanding stents, vena cava filters and
septal repair devices. The NMT Neurosciences division serves the needs of
neurosurgeons with a range of products including cerebral spinal fluid shunts,
the Selector(R) Ultrasonic Aspirator, Ruggles(TM) Surgical Instruments, the
Spetzler(TM) Titanium Aneurysm Clip, and endoscopes and instrumentation for
minimally invasive surgery.

This press release contains "forward-looking statements" within the meaning of
the Private Securities Litigation Reform Act of 1995. Such forward-looking
statements involve known and unknown risks, uncertainties or other factors which
may cause actual results, performance or achievements of the Company to be
materially different from any future results, performance or achievements
expressed or implied by such forward-looking statements. Factors that might
cause such a difference include, but are not limited to, those discussed under
the heading "Certain Factors That May Affect Future Results" included in the
Management's Discussion and Analysis of Financial Condition and Results of
Operations in the Company's Annual Report on Form 10-K for the year ended
December 31, 1998.
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