Volcano Capital invests in health care companies across a variety of asset classes including venture capital, public equities and debt. We provide funding and operational expertise to help entrepreneurs grow their healthcare businesses.


Douglas Wall
Bryan Grulke
Mariana Gantus

Douglas Wall, Managing Partner

Douglas Wall, known as Doug, serves as Managing Partner of Volcano Capital. Volcano Capital is a multi-strategy hedge fund and venture capital firm that invests in health care companies across a variety of asset classes including venture capital, public equities, and debt.  Doug began his career at medical device company, Vital Signs Inc., where he led investor relations and was involved in its $860 million sale to General Electric in 2008.  Doug enhanced his knowledge of the field as an analyst at Outer Islands Capital, where he managed coverage of medical technology and life science tools.   

Douglas serves as a board member for eight medical device companies, including Circa Scientific, Mercator MedSystems, Roxwood Medical, Transaortic Medical, Visionsense Ltd., Apex Medical, and HydroCision.  He also acts as board observer for five additional companies.

Bryan Grulke, Partner

Bryan Grulke is a Partner at Volcano Capital. Previously, he was an Investment Associate. Prior to attending business school, he worked as a Senior Manager in the Corporate Strategy group at Philips International, where he focused on medical imaging and life sciences. He also previously worked as an Associate Consultant at Bain & Company. Mr. Grulke graduated from Harvard Business School and Duke University, summa cum laude with a BS degree in Economics.

Mariana Gantus, Managing Director

Mariana Gantus is Managing Director at Volcano Capital. Previously she worked at Christie's as a Vice President where she focused on business development & deal oversight for nearly 10 years. Ms. Gantus graduated with a Bachelors of Arts degree in both Art History and Communication from The University of Southern California in Los Angeles and has her Master of Business Administration from Cornell University.