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                                                                    EXHIBIT 99.1

GUIDANT
PRESS RELEASE

DATE:           August 11, 1998

Guidant         Todd McKinney, Investor Relations, 317-971-2094
CONTACTS:       Carol A. Lindahl, Media Relations, 651-582-4461
                Rob Allen, Media Relations, 317-971-2031

InControl       Phil M. Okeson, CFO and Treasurer, 425-861-9800, Ext. 157
CONTACTS:       Sean M. Cleary, Vice President, Worldwide Marketing and Sales,
                     425-861-9800, ext. 660


      GUIDANT TO ACQUIRE INCONTROL FOR APPROXIMATELY $135 MILLION IN CASH

INDIANAPOLIS, IN AND REDMOND, WA -- AUGUST 11, 1998 -- Guidant Corporation
(NYSE and PCX: GDT), a world leader in the treatment of cardiovascular disease
through innovative medical devices, and InControl Inc., (NASDAQ: INCL), a
pioneer in the development of device technology for the treatment of atrial
arrhythmias, today announced that a definitive agreement has been signed,
setting the stage for Guidant to acquire InControl.

"The acquisition of InControl, with its unmatched understanding of device
treatment for atrial arrhythmias, complements our leadership position in the
treatment of ventricular arrhythmias and creates exciting new opportunities for
Guidant's future product portfolio," explained James M. Cornelius, Guidant
chairman of the board of directors.

Pursuant to the terms of the agreement, each outstanding share of InControl
common stock will be purchased for $6.00 in cash, for a total purchase price in
excess of $135 million. To implement the agreement, Guidant will commence a
cash tender offer within five business days. The completion of the tender offer
is subject to a number of customary conditions, including the acquisition of a
majority of InControl's outstanding common stock on a fully diluted basis and
the expiration of the waiting period under the Hart-Scott-Rodino Act. Shares
not purchased under the tender offer will be acquired in a subsequent merger at
the same price as soon as practicable after completion of the tender offer. The
acquisition will be accounted for under the purchase method and will result in
a one-time charge of approximately $90 million, which represents the value
assigned to purchased research and development. Excluding this one-time charge,
the acquisition is not expected to be materially dilutive to Guidant's earnings.

Ron Dollens, Guidant president and CEO, commented, "With the acquisition of
InControl we gain access to the pre-eminent intellectual property portfolio in
the field of device-based delivery of atrial therapies. Moreover, we gain an
organization whose knowledge of atrial arrhythmias is without equal. We plan to
merge operations of InControl into our Cardiac Rhythm Management business
group."


GUIDANT CORPORATION
P.O. BOX 44906  INDIANAPOLIS, IN 46244  TEL:317 971 2000  FAX:317 971 2040

  
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"Atrial arrhythmias represent an enormous unmet clinical need," according to
Jay Graf, president of the Guidant CRM Group. "The acquisition of InControl
will substantially enhance our ongoing work in creating devices that treat
multiple heart rhythm disorders. We believe that a variety of pacing,
defibrillation and ablation therapies will be used to treat atrial heart rhythm
disorders in the future. The InControl patent portfolio provides us with the
freedom to create advanced devices designed to provide physicians with maximum
flexibility to match therapy to patient need."

"Guidant was clearly our first choice as a business partner," noted Kurt C.
Wheeler, chairman, CEO and president of InControl. "We match up well
technologically, culturally and in a common view of how patients with atrial
arrhythmias will be managed." InControl's main product is the Metrix (TM), an
implantable atrial defibrillator. The Metrix has CE mark approval and is being
sold in Europe. It is in clinical investigation in the United States. Guidant
intends to complete that clinical trial and seek FDA approval to market in the
United States.

A global leader in the medical device industry, Guidant provides innovative,
minimally invasive and cost-effective products and services for the treatment
of cardiovascular and vascular disease.

InControl designs, develops and manufactures devices for the treatment of
atrial arrhythmias.

For more information about Guidant's products and services, visit the company's
Web site at http://www.guidant.com.

For more information about InControl, visit InControl's Web site at
http://www.incontrol.com.


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GUIDANT CORPORATION
P.O. BOX 44906 INDIANAPOLIS, IN 46244 TEL: 317 971 2000 FAX: 317 971 2040