Abbott Laboratories and St. Jude Medical each have deep experience in using sales of slower-growing medical products to drive investment in the next technological ­breakthrough.

But now the market will be watching closely to see if the two companies — which combined last week — can keep that going while managing high debt, working several other pending deals and ­melding differences in their corporate cultures.

“St. Jude Medical is a little more of an innovator or a fast-follower” in medical device innovation, BMO Capital Markets analyst Joanne Wuensch said in comparing Abbott and St. Jude cultures. “Abbott is a large global organization; some would call it a conglomerate. Over 50 percent of their revenue is generated in emerging markets. … I would agree there is a cultural difference.”

Last Wednesday, Abbott paid roughly $23.6 billion to acquire St. Jude Medical, including $13.6 billion in cash and $10 billion in Abbott common stock, according to filings with the Securities and Exchange Commission (SEC). In addition, Abbott took on about $5 billion in St. Jude debt.

Before the deal, which was announced last April, Abbott had $20.4 billion in annual revenue from sales of branded drugs, nutritional products, diagnostic devices and medical technologies like stents. St. Jude had $5.5 billion in sales of advanced medical devices like pacemakers.

Stents and pacemakers are in mature, slower-growing device markets, but both companies have used those sales to drive investments in, for example, cutting-edge products that can treat heart-valve diseases without open-heart surgery.

Now Abbott has committed to working down its debt and holding onto an investment-grade rating for its bonds, while also increasing its operating margin from the mid-20 percent range today to about 30 percent by 2019. Sales will be ramped up and administrative costs will be cut to achieve those goals.

Abbott Chief Executive Miles White has said the combined company will be able to find $500 million in annual “synergies” by 2020.

About one quarter of that amount will come from adding St. Jude’s higher-margin products to Abbott’s product line, boosting the combined company’s overall gross margins. Another quarter will come from expanded sales made possible by offering purchasing officials at hospitals a broader product ­catalog.

The remaining $250 million will come from cutting duplicative general and administrative costs from the combined organization. “Obviously there are some costs and expenses that would be duplicative that we are unfortunately going to have to synergize, etc.,” White told investors in an April conference call, according to a transcript on file with the SEC.

Many of St. Jude’s senior executives have signed retention agreements to stay on with Abbott after the transition, including former St. Jude CEO Michael Rousseau, who is heading up Abbott’s cardiovascular and neuromodulation division.

No word on 18,000 workers

No other announcements have been made regarding St. Jude’s 18,000 employees, including the 4,000 or so who work in Minnesota, though Abbott said it conducted an extensive review of St. Jude’s operations before announcing its synergy savings that will mount over time.

“It ramps steadily over several years. We’ll obviously want to get to the synergies as rapidly as we can, because that’s a great benefit to fall through to the bottom line,” White told investors.

Abbott has a good deal of business complexity to work through this year beyond integrating St. Jude, including a messy situation in which Abbott is suing a company that it agreed to acquire just a year earlier.

Abbott initially offered to buy diagnostics-device maker Alere for $5.8 billion, but it recently filed a lawsuit to cancel the deal after Alere restated earnings, pulled a product off the market, and saw its diabetes division excluded from Medicare after billing for patients who had already died, Bloomberg News has reported. An Alere spokesman told Bloomberg that it has complied with all deal terms and that Abbott’s lawsuit is without merit.

Also this year, Abbott will be divesting three products for minimally invasive vascular surgery to Japan-based Terumo Corp. for $1.1 billion in a deal that was inked amid antitrust scrutiny into the St. Jude deal. The Terumo divestitures were contingent on the St. Jude deal closing.

Finally, Abbott is working toward a $4.3 billion sale of its medical-optics equipment business, including its line of LASIK vision-correction devices, to Johnson & Johnson. That deal is expected to close in the first quarter. Though Abbott will generate some cash from the sale, it will also be losing several product lines with higher profit margins.

All those factors have injected uncertainty into analysts’ forecasts for Abbott’s earnings in the next year.

And because Abbott sells such a diverse set of health care products, gains from enhanced sales of St. Jude’s implantable heart devices and other high-tech offerings could be offset by weaknesses in Abbott’s sales of powdered milk for babies in China.

“We do believe [Abbott’s] diversified business model and solid growth across each of its other businesses will mitigate what seems to be a protracted … impact from its Chinese Nutritionals business,” analysts with Leerink Partners wrote last week. “But we remain on the sidelines pending more clarity on progress of the [St. Jude] integration. If the integration is seamless, ABT shares could meaningfully appreciate from current levels.”