Guidant Corp. (GDT) said Thursday it recalled some of its top-selling Insignia and Nexus implantable pacemakers because of failures, including nine cases requiring emergency hospitalization.

Since June, Guidant has June recalled 88,000 heart defibrillators — including its leading seller, the Contak Renewal 3 (search) — and issued warnings about 28,000 pacemakers because of malfunctions. Analysts said those actions applied to about 20 percent of the company's products.

The company said the latest failures had occurred at low rates in 40 models of the Insignia and Nexus pacemakers, but that the Food and Drug Administration (search) had labeled as a recall its notice that some might permanently lose pacing output without warning.

Other reported failures include loss of telemetry and appearance of a reset warning message.

No deaths have occurred because of the problems, Guidant said.

Guidant also said it had notified doctors that the failure rate for two defibrillators — the Contak Renewal and Contak Renewal 2 — was nearly triple what it had earlier estimated. The company also said the devices had been associated with three deaths, an increase from one death reported earlier.

Indianapolis-based Guidant projected a failure rate for the defibrillators of 0.7 percent to 1.8 percent.

The pacemakers, attached to the heart by wires, use mild electrical current from a battery to speed a slow heartbeat. Defibrillators use a bigger jolt on hearts that go into life-threatening irregular heartbeats. Surgery to remove and replace the devices is risky.

Guidant said Thursday that, as of Sept. 6, it had confirmed loss of pacing output in 36 of 49,500 Insignia and Nexus pacemakers, including seven that were detected by doctors before being implanted. No such failures had been found in devices shipped since March 2004, after a supplier made changes in the manufacture of a timing component, Guidant said.

The company reported telemetry failures in 16 of 341,000 of the pacemakers as well.

Company spokesman Dave Knutson said the most recent recall and safety notification came as a result of an almost two-week FDA inspection that ended Sept. 1 at Guidant's Cardiac Rhythm Management facilities in St. Paul, Minn. During the inspection, FDA officials requested five years worth of records from the company, he said.

The announcement affects about 56 percent of the company's pacemakers.

Shares of Guidant fell 2 cents to $69.47 in midday trading on the New York Stock Exchange. Shares of New Brunswick, N.J.-based Johnson & Johnson (JNJ), which is planning to acquire Guidant for $25 billion, rose 39 cents to $65.09.

J&J spokesman Jeffrey Leebaw said Thursday the company stands by its August statement that they continue to work with Guidant on the impact of the recall announcements and expect a decision on the merger by the Federal Trade Commission (search) in October.