UPDATE 2-Tenet reveals U.S. probe of ICDs, posts profit

* Q2 adj EBITDA up 8.9 pct to $268 mln; backs 2010 outlook

* Says Department of Justice wants Medicare claims records

* Shares fall 4.1 percent (Adds DOJ investigation, earnings, analyst's comments, byline, updates share price)

By Susan Kelly

CHICAGO, Aug 3 (Reuters) - Tenet Healthcare Corp (THC.N) said cost controls helped it post a quarterly profit, but its shares fell after it disclosed a U.S. probe into Medicare claims for heart device implants at one of its hospitals.

Tenet said the U.S. Department of Justice is investigating whether one of its hospitals fraudulently billed Medicare for heart defibrillator implant surgeries.

Its shares slumped 19 cents, or 4.1 percent, to $4.40 on the New York Stock Exchange.

The Dallas-based hospital operator, in its 10-Q filing, said the DOJ in March requested documents under the federal False Claims Act related to Medicare claims for implantable heart defibrillator procedures dating back to 2002.

Tenet said it believes the department is seeking patient records and other information to determine whether ICD procedures that were performed followed Medicare coverage requirements.

ICDs are implanted in a patient's chest to treat abnormally fast heart rhythms that could result in sudden cardiac death.

SECOND-QUARTER PROFIT

Tenet said cost efficiencies and the treatment of more patients with higher-paying health plans helped offset declining overall patient admissions, boosting profit in the second quarter.

"They do have price increases year over year, and those price increases have been meaningful," said CRT Capital Group analyst Sheryl Skolnick.

Admissions declined by 2 percent in the quarter. Patient volumes softened in the final weeks of June and in July, Tenet Chief Executive Trevor Fetter said on a conference call.

Fewer patients entered the hospital for flu treatment or childbirth -- a reflection of the weak economy, Fetter said. With more Americans out of work, birth rates are down and many people are shunning medical care due to lack of insurance coverage.

"The trends are similar to what we've been seeing all year," Fetter said.

Tenet's volume of commercial managed care patients fell 7.2 percent in the quarter. Outpatient visits slipped 0.8 percent.

Second-quarter net income was $25 million, or 5 cents a share, compared with a net loss of $15 million, or 3 cents a share, a year earlier. Earnings per share from continuing operations were 7 cents, compared with 1 cent a year before.

Operating revenue rose 3.3 percent to $2.3 billion.

Analysts had expected a profit of 6 cents a share on revenue of $2.3 billion, according to Thomson Reuters I/B/E/S.

Adjusted earnings before interest, taxes, depreciation and amortization rose 8.9 percent from a year before to $268 million.

Bad debt expense increased by $6 million, or 3.6 percent.

Tenet confirmed its full-year EBITDA outlook of $1.035 billion to $1.1 billion. (Reporting by Susan Kelly, editing by Gerald E. McCormick)