Updates shares, adds milestone in paragraphs 1,6

By Siddhi Mahatole and Sriparna Roy

July 17 (Reuters) - Intuitive Surgical ISRG.O shares slid about 13% to hover near their lowest in more than two years on Friday after the surgical robot maker warned that changes to Obamacare plans could dampen demand for surgeries, and stuck to its annual procedure growth outlook.

The warning revived concerns over procedure volumes as a fallout of the loss of enhanced subsidies under Affordable Care Act or Obamacare plans, a risk Abbott ABT.N brushed off as a "flawed assumption" a day earlier.

HCA Healthcare HCA.N, the largest for-profit U.S. hospital operator, earlier this week flagged softer surgical demand and a rise in uninsured patients as pandemic-era ACA subsidies expired.

"We thought medtech was set for a relief post ABT (Abbott) print," Evercore ISI analyst Vijay Kumar said, adding that softness in Intuitive's U.S. procedures, which is slowest in three years, rekindles the debate.

Stryker SYK.N shares fell more than 3%, while other medtech firms Boston Scientific BSX.N slipped 1.4% and Medtronic MDT.N was marginally down. Abbott was up 2%.

Intuitive is set to lose nearly $14 billion from its market value, if losses hold.

The selloff appears "increasingly overblown," Leerink Partners analyst Mike Kratky said, even as insurance-related changes add uncertainty to U.S. procedure growth.

COVERAGE CHANGES AFFECT CARE TIMING

Intuitive expects 2026 worldwide da Vinci-assisted procedure growth to come near the midpoint of its forecast of 13.5% to 15.5%.

Da-Vinci systems are used in a broad range of procedures, including weight-loss surgeries.

Intuitive's quarterly procedure growth was 12%, down from 14% in the first quarter, due to softness in surgeries that can be deferred.

"In our customer conversations, some have said changes in patient coverage and premium dynamics may be affecting when patients seek care and move forward with treatment," said CEO David Rosa.

Intuitive said the expiration of the subsidies also had a "modest adverse impact" on second-quarter procedure growth, without quantifying it.

At least a dozen brokerages have cut their price targets on the stock.