iRhythm Technologies, Inc., a medical device, service and technology company that develops and markets simple, innovative diagnostic monitoring solutions, today announced that it closed $16 million in Series D venture financing. Norwest Venture Partners (NVP), a global venture capital and growth equity investment firm, led the round, and existing investors including New Leaf Ventures, Synergy Life Science Partners and Kaiser Permanente Ventures also participated. iRhythm will use this infusion of capital to fund commercial expansion and accelerate the development of new technologies and applications.

"We are pleased to have NVP as our lead investor in this important growth phase of the company," said Kevin King, president and CEO of iRhythm. "Since the introduction of the Zio® System in early 2011, we have reported on over 20 million hours of patient data. Recent peer review data has demonstrated that the Zio® Patch System is helping physicians to make more informed patient treatment decisions over the gold standard method of Holter Monitoring. NVP's interest in partnering with companies focused on products that address an unmet clinical need aligns with iRhythm's own mission."

iRhythm's Zio® Patch System is comprised of the Zio® Patch and Zio® Report, which work together to provide an efficient diagnostic tool and a positive patient experience. The Zio® Patch is a single-use monitor, cleared by the FDA for up to 14 days of continuous wear, which results in uninterrupted, beat-to-beat capture when adhered to a patient. Once monitoring is complete, data from each Zio® Patch is processed and analyzed by Certified Cardiac Technicians using iRhythm's proprietary rhythm analysis. The resulting Zio® Report is designed to streamline the diagnostic process by highlighting key findings.

A study published by Pacing and Clinical Electrophysiology Journal last month showed that the Zio® Patch System demonstrated improved clinical accuracy and detection of potentially malignant arrhythmias in AF patients when compared with 24-hour Holter monitoring of the same patient. The study resulted in a change in treatment strategy for nearly one-third of patients with paroxysmal atrial fibrillation.

iRhythm also announced that Casper de Clercq, partner at NVP, has joined the company's board of directors. With 25 years of experience in the medical device and life sciences industry, Casper's focus at NVP is on mid- to late-stage investments in medical devices, specialty pharmaceuticals, digital health and healthcare IT. Products that address critical unmet medical needs and lower the total cost of healthcare are of particular interest to NVP.

"By combining advances in electronics and dramatically simplified ergonomics, iRhythm has developed an FDA-cleared medical device which intuitively improves patient compliance and diagnostic utility," said de Clercq. "iRhythm provides a comprehensive diagnostics service with computer data analytics to augment what has historically been a labor intensive interpretation process. The recent study shows that the Zio® Patch System offers a significant improvement in diagnostic accuracy over traditional 'gold-standard' Holter monitoring. Hospitals and payers have taken note of this solution because of the efficiency and efficacy for patients and physicians, which have the potential to reduce overall cost of care."

About iRhythm Technologies, Inc.
iRhythm provides innovative diagnostic monitoring solutions that facilitate early diagnosis and treatment decisions, with the goal of ultimately improving patient health outcomes and reducing wasteful healthcare spending. Its flagship product, the Zio® Patch, is designed to optimize and simplify the diagnosis of cardiac arrhythmias. For more information, please visit www.irhythmtech.com. Follow iRhythm on Twitter @iRhythmTech.

About Norwest Venture Partners
Norwest Venture Partners (NVP) is a multi-stage investment firm that has partnered with entrepreneurs to build great businesses for more than 50 years. The firm manages over $3.7 billion in capital and has funded more than 500 companies since inception. Headquartered in Palo Alto, Calif., NVP has subsidiaries in Mumbai and Bengaluru, India and Herzelia, Israel. NVP makes early to late-stage venture and growth equity investments across a wide range of sectors including: technology, information services, business services, financial services, consumer products/services and healthcare. For more information, please visit www.nvp.com Follow NVP on Twitter @NorwestVP