Investing in a medical device company these days does not come cheap. Venture capitalists said at a panel during Thursday’s MedTech Investing Conference in Minneapolis that the cost and risk of bringing medical device start-ups to market has gotten so expensive, it has caused at least one of them to change their business model.

Jan Garfinkle, managing director of Ann Arbor-based Arboretum Ventures, said her venture capital firm used to be 75 percent focused on medical devices and diagnostics. She estimates that will be modified to 60 percent, with the remaining going toward healthcare services and life science tools.

Garfinkle said the environment has changed from three or four years ago when venture capital firms could spend a smaller amount of money to build promising products that could be sold to strategic partners. Now, she estimates it takes about $20 million to get enough clinical data needed to satisfy a strategic partner.

Take the firm’s own portfolio company, VasoNova. Arboretum Ventures and other syndicates expected to invest $5 million into the catheter business, Garfinkle said. It ended up being a $19 million investment by all the syndicates and it took much longer than expected for the company to be sold, she said. VasoNova was purchased by med-tech business Teleflex in a deal valued at up to $55 million earlier this year.

“The good news is, it went from flip to flop to save,” Garfinkle told conference attendees at The Graves 601 Hotel on Thursday morning. The MedTech Investing Conference was co-presented by trade group LifeScience Alley and International Business Forum.

Other panelists discussed the relationships start-ups can have with strategic partners, larger companies that may one day have an interest in acquiring the small business.

Eric Simso, former vice president of strategic alliances for Boston Scientific, said it’s possible for companies to build products for the purpose of one day selling them to strategic partners.

“It certainly can and has worked,” Simso said.

He said some things companies should consider is that the product is easy to integrate into the strategic partner’s business and that meaningful clinical data is at hand.

But what about strategic partners selling their technologies to entrepreneurs to further innovate?

“We spent a fair amount of time looking at that,” Simso said. “We had limited success, frankly.” Simso said one of the issues is it’s hard for strategic partners to “disentangle some of these technologies” from their business.