Management Team
John Zehren
CEO & Board Member
John Zehren, as the CEO of Single Pass brings over 30 years of commercial and leadership experience in medical devices. He specializes in commercialization having launched numerous medical devices. With FDA approval of the first electrocautery device for biopsy closure, John is essential in the company’s commercialization success. He also served as CEO of the Green OR, Chief Commercial Officer of Endologix and Cagent Vascular, VP at Medtronic, Covidien, and Edwards Life Sciences. John’s extensive experience and significant level of success at all revenue stages is critical in scaling high-potential ventures like Single Pass.
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Dan Hughes
Head of Sales Operations
Dan comes to us with over 30 years of Medical Device Sales Experience in recent leadership roles at Medtronic Neurovascular, RapidAI and Mivi Neurosciences. He is leading the U.S. Commercial launch with our distribution partners and developing commercial strategy for the only FDA approved Biopsy Closure device. Dan has a reputation as a builder of successful teams and structures within the neurovascular space. His strengths in this environment include developing compensation programs heavily weighted towards overachievers, streamlining communication, and attracting the highest level of professional. ​
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Steve Fried
Head of Commercial Excellence
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Steve Fried is a seasoned healthcare marketing and sales leader with over 25 years of experience driving growth for medtech and AI health startups. He has led commercial teams at Viz.ai, RhythmX AI, Regard, and Medtronic, scaling revenue and securing major IDN partnerships. A former cardiovascular perfusionist, Steve combines clinical insight with proven go-to-market execution. At SinglePass, he guides the Western U.S. sales strategy and health system engagement.​
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Randall Takahashi
Chief Engineer
Randall Takahashi is a seasoned medical device engineer with over 21 years of experience across the Neurovascular, Cardiovascular, Ophthalmology, and Dental sectors. As Chief Engineer, he leads the development of Class I–III devices, including catheters, guidewires, drug-delivery systems, and implantables. Randall has deep expertise in the full product development cycle, advanced manufacturing, and materials selection. He holds 19 issued and pending patents and has held senior leadership roles at Medtronic, Abbott, and Balt, as well as co-founding multiple ventures. Known for his collaborative style and commitment to innovation, Randall values engineering integrity, design excellence, and transparency. He earned a B.S. in Biomedical Engineering from UC San Diego.
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Meera Shier
SVP Marketing
Meera Shier joins the Single Pass team after 16 years of experience in the Neurovascular space. Most recently, she led Global Marketing at Terumo Neuro (MicroVention) and consistently drove growth and revenue achievement. Prior to Terumo, Meera was a senior marketer and product launch leader at ev3/Covidien. Meera brings extensive experience launching innovative medical devices globally, building impactful brands, establishing deep customer relationships, and creating promotional programs to drive adoption and awareness. She will leverage her experience and skills to further expand and develop Single Pass's presence in the market.
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Ryan Ippolito, CPA, MBA
CFO
​Ryan Ippolito is a finance executive with more than 25 years of experience supporting high-growth companies across the life sciences, medical device, pharmaceutical, SaaS, and consumer sectors. He has held senior leadership roles in both public and private organizations, helping raise over $250 million in capital and leading M&A transactions exceeding $300 million. Ryan currently serves as CFO for multiple medical device startups, where he has supported initial commercialization and driven meaningful revenue growth. Previously, he served as CFO of Terumo Neuro (formerly MicroVention), a nearly $1 billion global leader in interventional neurology, where he led revenue expansion, EBITDA growth, global operational scaling, and strategic acquisitions.
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Board of Directors
Dave Ferrera
Board Member
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David Ferrera is an entrepreneur, engineer and inventor with nearly 30 years of experience in the medical device industry. He is CEO of RC Medical, an Orange County venture studio advancing interventional neurology and radiology innovations in collaboration with physician-entrepreneurs. Dave is CEO of Sonorous Neurovascular, a spinout of RC Medical. He previously served as CTO of Balt Global and co-founded Blockade Medical, acquired by Balt in 2016. His earlier roles include successful leadership positions at MindFrame (acquired by Covidien), Microvention (acquired by Terumo), and Micrus Endovascular (acquired by Johnson & Johnson). Mr. Ferrera holds over 80 patents and authored Innovation in Translation (Advantage-Forbes, 2021). He sits on multiple medical device boards and holds a B.S. in Plastics Engineering from UMass Lowell.​
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Sam Milstein
Board Member
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Sam Milstein is a seasoned biotechnology entrepreneur and investor with over four decades of experience founding, leading, and advising life science companies. He is CEO of Mortar & Pestle Consulting, offering strategic and technical expertise to biotech firms and investors. He co-founded or held executive roles at pioneering companies including Emisphere Technologies, Ception Therapeutics (acquired by Cephalon), and Athena Neurosciences (acquired by Elan). He currently serves as Board Chair of Cerus Endovascular, and is a Board Member of the Regenerative Medicine Foundation. He also advises early-stage ventures through the Mid-Atlantic Bio Angels. His career spans drug discovery, stem cell therapeutics, medical devices, and venture development.​
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Peter Sunenshine, MD
Board Member & Co-Founder
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Dr. Peter Sunenshine, MD, serves as the Chief of Neurointerventional Radiology at Banner University Medical Center in Phoenix, AZ, and holds a clinical assistant professorship at the University of Arizona College of Medicine - Phoenix. He completed a comprehensive 7-year residency program in radiology, neurology, and neuroradiology at New York University Medical Center/Bellevue Medical Center, followed by a fellowship in Neurointerventional Radiology at NYU. With over 15 years of experience, Dr. Sunenshine is a seasoned Neuroradiologist/Neurointerventional Radiologist, actively involved in various research projects and clinical trials.
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Paul Brooke
Board Member
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Paul Brooke is a seasoned healthcare executive and investor with decades of leadership across biotech, medical devices, and finance. He served as Chairman of Caelum Biosciences until its acquisition by AstraZeneca in 2021, and was a board member at Cerus Endovascular until its sale to Stryker in 2023. He currently chairs Browne Trading and serves on the board of Sonorous. Mr. Brooke is Managing Member of PMSV Holdings, a private investment firm, and was a founder and managing partner of venBio. He previously held senior roles at Morgan Stanley and Tiger Management, and has served as a director of several public and private companies. He brings deep expertise in healthcare strategy, investment, and board governance, with decades of experience guiding innovative companies to successful outcomes.
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Stephen Griffin
Board Member
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​Stephen Griffin brings almost 30 years experience in the medical device industry, working in the peripheral vascular, neurovascular and cardiovascular disease states. With a PhD in Biomedical Engineering from the University of Limerick, he started his career in R&D and held various technical and leadership positions. Most recently, Stephen, as CEO at Cerus Endovascular, was at the forefront of design and development of a platform of neurovascular Class III devices, and led the company through a successful transaction with Stryker Corp. in 2023. He brings a unique combination of technical expertise, clinical understanding, and commercial strategy to the medical device space.
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Shahin Enayati
Board Member
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Shahin Enayati is a purpose-driven entrepreneur and operator with over 25 years of experience building and scaling companies at the intersection of health, safety, and technology. He is the Founder and Managing Partner of Response Ready, a diversified emergency preparedness platform with B2B and B2C brands including CPR1.com, AEDLeader.com, and MDSIMedical.com. His work spans acquisitions, digital innovation, and vertical integration—empowering businesses and communities to better prepare for medical emergencies. Through his investment firm, Sustain Equity, and venture studio, Made Noble Companies, Shahin backs and accelerates impact-focused ventures. He brings a strategic, investor-minded approach to leadership and is committed to leveraging technology, education, and proactive planning to build safer, more resilient futures for individuals and organizations alike.
Kevin Hirsch, MD
Board Member & Co-Founder
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​Dr. Kevin Hirsch, a highly respected interventional radiologist, graduated from the University of Southern California School of Medicine in 1998. He joined Banner University Medical Center-Phoenix, elevating its interventional radiology program to a top referral center and later becoming Chair of the Department of Radiology in 2006. With extensive leadership experience and committee involvement, he played a key role in establishing programs like interventional oncology and the Interventional Stroke Program, making Banner University Phoenix the first certified Comprehensive Stroke Center in Arizona. Dr. Hirsch, a lifelong educator, was appointed Interim Chair of Radiology at University of Arizona College of Medicine, Phoenix in 2015 and has been promoted to full Clinical Professor. A consultant to the medical industry and co-founder of a medical device company, he continues to lead in research and clinical trials. Voted as one of Phoenix Magazine's Top Docs, Dr. Hirsch enjoys family time outside of his medical endeavors.
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Single Pass is headquartered in Lake Forest, California, and has pioneered a patented battery-powered electrocautery device for cauterizing deep tissue biopsy channels post solid organ procedures. Developed by Dr. Peter Sunenshine, a renowned Interventional Radiologist and Chairman at Banner University Medical Center in Phoenix, Arizona, this innovative technology revolutionizes biopsy procedures. With a management team boasting over 100 years of collective experience in successful medical device development and commercialization, Single Pass operates from its ISO certified facility in California, ensuring excellence in product quality and performance.
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Click Here to Hear Dr. Sunenshine Discuss The Origins and Benefits of Single Pass.
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