Clinical Team


Dominic A. Munafo M.D. FABSM

Board Certified Sleep Medicine Specialist
Chief Medical Officer – Sleep Data

Dr. Munafo represents over 25 years of medical expertise diagnosing and treating patients with sleep-disordered breathing. As Chief Medical Officer at Sleep Data, Dr. Munafo designed and implemented clinically validated protocols based on his extensive experience and research related to the cardiovascular consequences of sleep-disordered breathing. His medical and academic placements include the University of California, San Diego, where he joined the university’s faculty in 1993 as an Assistant Professor, and Baylor College of Medicine in Houston, Texas, where he completed his residency in internal medicine and earned his M.D. Prior to his 2000 Medical Director role at Sleep Data, Dr. Munafo provided care to patients at a pulmonary/critical care and sleep medicine private practice based in San Diego’s North County. Dr. Munafo thought that his medical training had exposed him to the extremes of sleep deprivation, but nothing could have prepared him for the sleep deprivation of being the father of three boys and a girl. He and his wife JoAnna love to swim, bike and run.

Derek H. Loewy Ph.D., D.ABSM, CBSM

Board Certified Behavioral Sleep Medicine Specialist
Co-founder – Insomnia Program, Stanford Sleep Disorders Center

Dr. Loewy has worked within sleep medicine for over 25 years, including extensive involvement in sleep research, consulting with the sleep industry, and practicing clinical sleep medicine. As current Director of Behavioral Sleep Medicine at the Scripps Clinic Sleep Center, Dr. Loewy worked closely with sleep-challenged patients to overcome a wide range of disorders. Dr. Loewy contributed his knowledge and expertise to numerous internationally-recognized sleep institutes, completing his doctoral degree in Canada at the University of Ottawa in 1996, his research fellowship at the University of Arizona in 1999, and his sleep medicine fellowship at the Stanford Sleep Disorders Center in 2001. A licensed clinical psychologist, board certified sleep specialist, and behavioral sleep specialist, Dr. Loewy proudly co-founded the Stanford Insomnia Program, which has served thousands of patients since inception. An avid photographer and hobbyist chef, Dr. Loewy is currently penning a children’s book to help explain nightmares.

Bretton Hevener B.S., RPSGT

Registered Polysomnographic Technologist
President – Sleep Data

Bretton has over 14 years of experience in Sleep Medicine. She began her career at the National Jewish Medical and Research Sleep Center and the University of Colorado’s Children’s Hospital Sleep Center in Denver, Colorado as a sleep technologist. In 2005, she transitioned from the clinical side of sleep medicine to operations. At her former company, Pacific Sleep Medicine, Bretton had direct involvement and oversight responsibilities for the sleep labs, clinical trials, and DME fulfillment.  During that time she directly administered thousands of sleep studies as a clinician and tens of thousands more in an oversight capacity as general manager. In 2010, Bretton brought her expertise to Sleep Data Services. At Sleep Data she has woven her experiences together to present a Sleep Care Management service focused on improving patient outcomes and providing population management metrics to customers.

Business Team

David French - CEO

Co-founder & CEO – Star Medical
Co-founder – Rock Island Capital

David French has expertly guided businesses through high growth and transitional periods for over 20 years, most recently as CEO of Sleep Data, San Diego County’s leading comprehensive sleep apnea company. Previously, David co-founded and served as president and CEO of Star Medical LLC, a nationally recognized durable medical equipment provider specializing in respiratory therapy products. He successfully served as Founder and President for French Investment Group LLC for five years before co-founding Rock Island Capital, a Midwest-based private equity fund for which he continues to serve as Operating Advisor.

A former Certified Public Accountant and Bachelor of Science in Business Administration graduate of the University of Missouri in Columbia, David French began his career within the audit and tax departments of Peat Marwick Mitchell (now KPMG). He resides in San Diego County with his wife, two children, two dogs, and fish. An avid golfer, David notices that he wins more side bets after enjoying a great night’s sleep.

Tay Nguyen - CTO

Co-founder – DivX
Technology Architect at Accenture

Tay Nguyen has established himself as a regional leader in new technology, organizational growth, and business development. An experienced technology entrepreneur and strategist, Tay served as President at Sleep Data starting in 2011, guiding the company toward record growth and recognition as a national player in the field of sleep medicine. Previously, as Co-Founder of DivX, a San Diego-based Internet media company, Tay managed the transition to a successful NASDAQ Initial Public Offering in 2007. During that tenure, he managed the company’s exponential growth from a handful of employers to several hundred.

As Technical Architect for Accenture, a global management consulting, technology services and outsourcing company, Tay served Fortune 100 companies in the energy industry, specializing in Enterprise Resource Planning (ERP) software and the highly respected, Germany-headquartered Systems, Applications and Data Processing (SAP) software. An enthusiastic surfer, snowboarder, and competitive volleyball player, Tay also participates in the most extreme sport of them all: fatherhood.

Thomas Lee - Chief Sleep advocate

Chief Sales Officer – ACI Wellness
Division Manager – Access Nurses

Thomas Lee represents over 15 years of progressive sales leadership experience across a wide range of industries. Prior to joining the Optisom team, Thomas Lee served as Chief Sales Officer at ACI Specialty Benefits, the San Diego-base benefit programs firm specializing in workplace wellness, concierge, and employee assistance programs. Thomas skillfully led the ACI sales team to execute worldwide sales initiatives and boost revenue growth, maintaining the company’s position within the Top 10 Employee Assistance Program Providers nationwide. As Division Manager with Access Nurses Inc., a major healthcare staffing provider, Thomas was recognized as Top Account Manager for 12 consecutive quarters.

A University of California, San Diego graduate, Thomas completed his Bachelor of Arts degree in Psychology. Thomas competes in obstacle races such as Tough Mudder and the Spartan Race. On his bucket list: helicopter transport to an Alaskan peak for an untamed snowboarding session.

Michael Floyd - VP Product

VP Product Management - BitTorrent
VP of Operations – DivX

Mr. Floyd is a seasoned technology veteran with over 25 years of technology product development, management and operations experience.  While at DivX he had various leadership roles including Vice President of Operations and Vice President of Engineering.  He also served as the Vice President of Product Management for BitTorrent Inc. where he was responsible for product strategy and development of a suite of products with over 180 million users.  Mr. Floyd has both a Bachelor and Masters degree in Computer Science from SDSU as well as an MBA with a specialization in Globalization from USC.

In addition to being a seasoned Pyrotechnician who has worked on more than 70 fireworks displays, he enjoys coaching Lego Robotics, backpacking and model rocketry.