TAKING THE PULSE: When U.S. medical-device companies start reporting first-quarter results this week, the focus will remain on how much health-spending cutbacks are hurting sales of expensive products such as surgical robots and replacement orthopedic joints. Companies making hips and knees, including Stryker Corp. (SYK) and Zimmer Holdings Inc. (ZMH), saw growth in the $11 billion market ease in the fourth quarter, and Wall Street projects more rough sledding in the first quarter. Cardiology devices aren't as exposed to economic pressure, but top heart device makers face important questions as well, including whether Medtronic Inc. (MDT) can maintain stability in its top device markets.

COMPANIES TO WATCH:

Intuitive Surgical Inc. (ISRG) - reports April 16

Wall Street Expectations: Analysts surveyed by Thomson Reuters predict earnings, excluding items, of $1.05 a share on sales of $204 million. A year ago, the maker of surgical robots reported net income of $1.12 a share on revenue of $188.2 million.

Key Issues: Sales of the company's expensive "da Vinci" robots have slowed due to recession-induced financial constraints at hospitals. The key question is when this pressure will ease, and the outlook has been hazy. Intuitive tends to address full-year guidance on each quarterly call, and any fresh projections for the year will be key.

Stryker Corp. (SYK) - reports April 20

Wall Street Expectations: Analysts surveyed project earnings of 71 cents a share on revenue of $1.64 billion, up slightly from 70 cents and $1.63 billion a year ago.

Key Issues: This quarter's growth outlook is meager for a company with a long history of 20% annual earnings growth, but Stryker faces challenges on multiple fronts. Its two key businesses - replacement joints and medical/surgical equipment - are under pressure from the recession in different ways, including capital-spending cuts that have hurt the latter.

Boston Scientific Corp. (BSX) - reports April 20

Wall Street Expectations: The company is seen posting earnings of 12 cents a share on revenue of $2.02 billion, down from 21 cents and $2.05 billion in the year ago period.

Key Issues: Boston Scientific' s outlook has appeared to improve amid signs its top products - implantable defibrillator and tiny heart stenos - have held up well in markets that have stabilized after long, rocky stretches. Continued solid performance in those markets is critical while the company controls costs and continues to pay down debt from its Guidant acquisition.

Zimmer Holdings Inc. (ZMH) - reports April 23

Wall Street Expectations: Analysts anticipate earnings, excluding items, of 94 cents a share on revenue of $1 billion. A year ago, Zimmer reported net income of $1.02 a share, including acquisition-related charges, on revenue of $1.06 billion.

Key Issues: Zimmer is the biggest pure-play company in the replacement-joint business, and therefore is most exposed to a sluggish market. But it has an added problem in the form of lost market share tied to sweeping changes in the way it interacts with surgeons. Zimmer has signaled that it expects further erosion this year before things even out, and projects slower-than-usual growth for the entire sector.

Medtronic Inc. (MDT) - reports May 18

Wall Street Expectations: Analysts expect fiscal fourth-quarter earnings, excluding items, of 82 cents per share on revenue of $3.84 billion for the quarter ending later this month. A year earlier, Medtronic had net income, including acquisition and restructuring charges, of 72 cents a share on revenue of $3.86 billion.

Key Issues: Prior-quarter results eased some concern about continued market-share erosion in top markets for products such as implantable defibrillator and spinal devices. Medtronic cited some signs of stability, and investors will be looking for continued progress. But the company has also said its spinal, diabetes and surgical technologies units could have some economic vulnerability.

(The Thomson Reuters estimate and year-earlier net may not be comparable due to one-time items and other adjustments)

-By Jon Kamp, Dow Jones Newswire; 617-654-6728; jon.kamp@dowjones.com

(Mike Barris contributed to this report.)