Guidant Initiates Worldwide Physician Communications Regarding Important Safety Information and Corrective Action about Implantable Cardiac Defibrillators.

INDIANAPOLIS -- Guidant Corporation (NYSE:GDT) said today it is voluntarily advising physicians about important safety information regarding certain devices. Guidant has apprised FDA of these actions, and FDA has indicated that it will classify them as recalls. These communications advise physicians and their patients of safety information and are intended to limit adverse events. Physicians should use this information to decide how best to treat their patients.

The devices are:

--VENTAK PRIZM 2 DR (Model 1861) ICDs manufactured on or before April 16, 2002.

--CONTAK RENEWAL (Model H135) and CONTAK RENEWAL 2 (Model H155) CRT-Ds manufactured on or before August 26, 2004.

--VENTAK PRIZM AVT, VITALITY AVT, RENEWAL 3 AVT and RENEWAL 4 AVT ICDs (All series numbers).

VENTAK PRIZM 2 DR DEVICES

As previously announced in May, Guidant communicated to physicians about a failure involving deterioration in a wire insulator within the lead connector block that, in conjunction with other factors, results in a short to the backfill tube, resulting in the device's inability to deliver therapy. As of today, there have been twenty-eight reports of this failure worldwide, including one death, in 26,000 devices built prior to an April 2002 change in the device. No failures have been observed in the devices built after the April 2002 change. Approximately 17,000 devices built before April 2002 remain in service, including approximately 13,900 in the United States.

For patients who have these VENTAK PRIZM 2 DR devices, Guidant recommends that physicians continue with normal follow-up patient visits at three month intervals. In addition, patients who have recently received a defibrillation shock should consult with their physician. For additional information and recommendations, see http://www.guidant.com/physician_communications/PRIZM2_DR.pdf. If a patient and physician decide to replace one of these devices, Guidant will provide a replacement at no charge.

CONTAK RENEWAL DEVICES

Guidant is communicating to physicians about a failure in its CONTAK RENEWAL (Model H135) and CONTAK RENEWAL 2 (Model H155) cardiac resynchronization therapy defibrillators manufactured on or before August 26, 2004. The failure involves deterioration in a wire insulator within the lead connector block that, in conjunction with other factors, results in a short to the active titanium case and results in the device's inability to deliver therapy. Fifteen reports of this failure mode have been confirmed in devices built on or before August 26, 2004 from approximately 16,000 devices implanted worldwide. This includes a patient death on May 30, 2005 involving a device returned earlier this week. The device is still being tested but it appears to have experienced this failure in conjunction with attempted delivery of at least one high-voltage therapy. Approximately 11,900 devices built on or before August 26, 2004 remain in service, including approximately 6,700 in the United States.

It is Guidant's recommendation to physicians that patients with these CONTAK RENEWAL devices should continue with normal follow-up visits at three-month intervals. In addition, patients who have recently received a defibrillation shock should consult with their physician. If a yellow warning screen appears on the programmer, the physician should fully trouble-shoot. For additional information and recommendations, see http://www.guidant.com/physician_communications/RENEWAL_RENEWAL2.pdf. If a patient and physician decide to replace one of these devices, Guidant will provide a replacement at no charge.

VENTAK PRIZM AVT, VITALITY AVT, AND RENEWAL AVT DEVICES

Guidant is communicating to physicians about certain Guidant ICD and CRT-D devices that include atrial therapy capabilities - all serial numbers of VENTAK PRIZM AVT, VITALITY AVT, RENEWAL 3 AVT and RENEWAL 4 AVT. These products are subject to a memory error, which may affect available therapy. Two incidents have been confirmed, neither of which resulted in death or injury, from approximately 21,000 devices implanted worldwide, including approximately 18,000 implanted in the United States. Guidant is recommending a programming change that can reduce the risk of this issue and that can be implemented at the next office visit. For additional information and recommendations, see http://www.guidant.com/physician_communications/AVT.pdf. Guidant is developing a non-invasive software solution for this issue, expected by year-end.

"Patient safety is paramount and our highest priority," stated Ronald W. Dollens, president and CEO, Guidant Corporation. "As a leading manufacturer of lifesaving technology, Guidant takes seriously its responsibility to create the most reliable products and services, enhance patient outcomes and limit adverse events to patients. The purpose of the company's recent communications is to share information with physicians and patients about problems in a small subset of Guidant devices. We will work with physicians as they decide how best to treat their patients."

Dollens continued, "Guidant is committed to establishing industry guidelines and processes to determine when, how and under what circumstances adverse events should be communicated to doctors and patients. Guidant hopes to work with FDA, other regulatory agencies and physicians to convene a panel to assist the medical device industry in establishing clear guidelines."

Additional information about these potential issues is available for physicians and patients at 1-866-GUIDANT (1-866-484-3268) (24/7) and http://www.guidant.com/physician_communications/.

This release includes forward-looking statements concerning the course of developments with respect to the affected products. These statements are based on assumptions about many important factors, including adverse event rates, regulatory agency actions, and other factors identified on Exhibit 99 to the company's most recent 10-Q. Actual results may differ materially. The company does not undertake to update its forward-looking statements.