iRhythm Technologies, maker of the Zio patch peel-and-stick heart monitor, has raised $17 million in a round led by Novo A/S, a Danish life sciences investment firm. Previous investor Norwest Venture Partners also participated in the round. This brings the company's total disclosed funding to about $85 million, based on SEC filings and company announcements. As part of the latest investment deal, Tiba Aynechi, PhD principal at Novo Ventures (US) Inc., has joined the company’s board of directors.

The Zio patch is a small wearable sensor, used for multi-day monitoring of arrhythmias in cardiac patients (up to a fortnight). Unlike many participants in that space, however, the device does not wirelessly transmit data to a mobile device. Instead, readings are stored in the patch itself, which is then mailed back to iRhythm at the end of the monitoring period. 

“We are pleased to have Novo A/S as a new investor, and with this funding we are poised to further accelerate our company’s growth,” Kevin King, president and chief executive officer of iRhythm, said in a statement. “Our Zio Service is setting a new standard for long-term continuous cardiac monitoring of patients with suspected arrhythmia. We believe our strong and growing success with physicians and payers underscores the Zio Service’s compelling value proposition of using novel technology to improve diagnosis of cardiac arrhythmias, while also increasing the efficiency of healthcare delivery.”

The company says it will use the funding for marketing, development, and continuing to accrue efficacy data for the technology, which they report has been used by almost 250,000 patients at over 800 sites.

At the beginning of the year, the Zio patch was validated against a traditional Holter monitor in a study conducted at the Scripps Translational Science Institute and published in the American Journal of Medicine. The study found that the Zio patches detected 96 arrhythmia events over two weeks of monitoring, whereas the Holter monitors detected 61. According to iRhythm, a more recent study found the Zio Service identified nearly five times as many cases of atrial fibrillation as the Holter in the same time frame.

Less than a month after the AJM study was published, Aetna updated its guidelines on cardiac event monitors to allow patients to be reimbursed for the technology.