Management Team

Jim Buck

President & CEO
Jim Buck joined Mardil Medical in September, 2010 after more than nineteen years of experience successfully developing and commercializing innovative medical technologies. Prior to joining Mardil, Jim served as President & CEO of SetPoint Medical, a privately funded early stage developer of an implantable neuromodulation device system to regulate uncontrolled inflammation; VP, marketing & business development at InnerPulse, a privately funded developer of a novel implantable defibrillator system; and VP, marketing & business development at Closure Medical, leading the product mapping strategy and execution for a breakthrough surgical sealant and adhesive technology culminating in a $370 million acquisition and integration into Johnson & Johnson.

Previous to Closure Medical/J&J, Jim held several positions of increasingly greater responsibility over eleven years at cardiac medical device leader St. Jude Medical. Jim holds a master of management from Northwestern University’s Kellogg Graduate School of management and a bachelor’s degree from Indiana University. Jim resides with his wife Lisa and four children in Orono, MN.


Spencer H. Kubo, MD

Chief Medical Officer
Spencer H. Kubo, M.D. was appointed as part time Chief Medical Officer for Mardil Medical in 2015. Previously, Dr. Kubo was Senior Vice President and Global Medical Director for Acorn Cardiovascular which developed CorCap, a cardiac support device. He was also Executive Director for Merck, leading the Academic and Professional Affairs department. Prior to that, Dr. Kubo was Professor of Medicine in the Cardiovascular Division of the University of Minnesota, where he was Co-Director of Clinical Cardiology and Medical Director of the Heart Failure-Heart Transplantation Program, which achieved national recognition for excellence in patient care and research.

Dr. Kubo has published more than 250 papers and abstracts, and is widely regarded as a leading researcher in heart failure. He has served on the editorial boards of several journals.

Dr. Kubo graduated from Dartmouth College with highest distinction and was elected to Phi Beta Kappa. He received his doctorate of medicine from Cornell University Medical College and was elected to Alpha Omega Alpha. His residency and cardiology fellowship training were completed at New York Hospital-Cornell Medical Center. He is a Fellow of the American College of Cardiology and the American Heart Association.

Dr. Kubo also practices part-time at United Heart and Vascular Clinic, part of Allina Health. He has a special interest in improving the process of care for patients with heart failure and reducing readmission rates


Aaron Hjelle

Vice President, Development
Aaron has spent over 20 years successfully developing implantable medical devices and delivery systems at SCIMed Lifesystems, Boston Scientific, Urologix, CVRX and Acorn Cardiovascular. One of Aaron’s most notable developments was a novel cardiac implant and minimally invasive delivery procedure which Mardil has acquired the intellectual property for, and will be leveraging in its own innovative minimally invasive product and procedure. Aaron lives in Brooklyn Park, MN with his wife Heather and three children.


Mark Kraus

Vice President, Operations, Supply Chain & Quality
Mark Kraus joined Mardil in March, 2016 with a track record of success and P&L accountability in rapidly growing manufacturing operations. Mark has over 25+ years of leadership experience in medical device product development, operations, quality assurance, supply chain, customer service, and general management positions, leading several companies through periods of significant product expansion and manufacturing growth. Prior to Mardil, Mark served as VP of Operations for Neometrics (Neometrics was acquired by Heraeus Medical Components in 2015), a privately held OEM guidewire design and manufacturing company, r4 Vascular, a privately held company focused on the development and commercialization of catheters and devices to serve the Vascular Access market, and the President of the Vascular Access and Delivery Systems business unit for Enpath Medical prior to being acquired by Greatbatch Medical. Enpath Medical achieved a leading market share position in venous introducers and delivery systems during Mark’s tenure with the company.

Mark has a bachelor’s degree in Mechanical Engineering from the University of Minnesota.


Jennifer Englund

Vice President, Clinical & Regulatory Affairs
Jennifer Englund joined Mardil Medical in February 2016. She brings 20 years of experience in the medical device industry, both at large established multi-national companies (Medtronic, Coloplast) and start-ups (Catheter Robotics, Symbios Clinical). The majority of Jennifer’s experience lies in clinical research in the cardiovascular space; developing research partnerships with physicians and working to bring a new therapies to market. Jennifer holds Bachelor of Science degrees in Biology and Psychology from the University of Minnesota. Jennifer lives in Minneapolis with her husband, Michael and son.


William Cohn, MD

Senior Medical/Surgical Advisor;
Director of Minimally Invasive Cardiac Surgery, Texas Heart Institute, Houston, TX

WilliamCohn William E. “Billy” Cohn, MD, is a professor of surgery at Baylor College of Medicine and an adjunct professor of bioengineering at both Rice University and the University of Houston. His major research interests include the development of new technology for decreasing the invasiveness of cardiac and vascular surgery.
Dr. Cohn has a passion for medical device development and has more than 90 US patents granted or pending, and another 60 international patents for his medical innovations. His numerous awards include an honorary doctorate in science from Oberlin College, the Distinguished Scientist Award, given by the MacDonald Fund, and the Edison Award for excellence in human-centered design and innovation for inventing the SentreHEART® Lariat® Suture Delivery Device.

In 2000, Dr. Cohn was named the distinguished Inventor of the Year by the U.S. Intellectual Property Owners Association and in 2014, he was named Outstanding Inventor of the Year by the Houston IPO. In addition, in 2014 he received an award for the most Innovative Medical Device Startup of the year at the Innovations in Cardiovascular Interventions Conference in Tel Aviv for inventing the TVA Everlinq system for percutaneous creation of AV fistulas and for founding TVA Medical. In 2015, he was awarded a Lifetime Achievement Award for healthcare innovation by the Houston Technology Center. In 2016, he accepted a full time role with Johnson & Johnson to lead the creation of the Center for Device Innovation at Texas Medical Center, a broad, new collaboration between J&J and TMC that aims to accelerate end-to-end development of breakthrough medical devices. Dr. Cohn’s service to Mardil and his vital role in the emergence of the VenTouch® System is one engagement that he has secured to continue forward.


George Gellert, MD

Chief Imaging Advisor;
Medical Dir. Interventional Echocardiography, Banner Univ. Med. Ctr., Phoenix, AZ

Dr. Gellert is a cardiac anesthesiologist with primary interest of 3-Dimensional Interventional Echocardiography. He presently serves as Medical Director of Interventional Echocardiography at Banner University Medical Center Phoenix, Arizona. Dr. Gellert is Board Certified by the American Board of Internal Medicine, the American Board of Echocardiography and the American Board of Anesthesiology.

Dr. Gellert has been in private practice for 24 years with Valley Anesthesiology Consultants in Phoenix, Arizona, and also on faculty at University of Arizona College of Medicine, Creighton University School of Medicine and Mayo Clinic College of Medicine.

Dr. Gellert is a consultant, trainer and proctor for Edwards LifeSciences THV TAVR, Medtronic HVT TAVR Global Field Team, Abbott Structural MITRACLIP, Philips HealthCare US and Siemens Medical US.

Dr. Gellert’s imaging courses and on-site proctoring have provided both surgical and interventional 3D-echocardiography education and hands-on training to hundreds of cardiologists, cardiac anesthesiologists and cardiac sonographers across the United States.