$100,000,000

Debt Securities

Common Stock

Preferred Stock

Warrants

Rights

Units

We may offer and sell from time to time, in one or more offerings, up to $100,000,000 in the aggregate of debt securities, common stock, preferred stock, warrants, rights or units consisting of any two or more of such securities. This prospectus provides a general description of the securities that may be offered.

Each time we offer and sell securities, we will provide specific terms of the securities to be offered and sold (including the amounts, prices and other terms) in a supplement to this prospectus (which may include, but is not limited to, an at-the-market sales agreement prospectus). This prospectus may not be used to sell securities unless accompanied by a prospectus supplement.

Our common stock is listed on the NYSE American under the symbol "STXS." As of March 12, 2026, the closing price of our common stock was $1.88. Each prospectus supplement offering any securities other than our common stock will state whether those securities are listed or will be listed on the NYSE American or any other securities market or other exchange.

We may offer securities through underwriting syndicates managed or co-managed by one or more underwriters, directly to purchasers or in any manner specified in a prospectus supplement. The prospectus supplement for each offering of securities will describe in detail the plan of distribution for that offering. For general information about the distribution of securities, see "Plan of Distribution" in this prospectus. No securities may be sold without delivery of this prospectus and the applicable prospectus supplement describing the method and terms of the offering of such securities.