NMT Medical, Inc. (NASDAQ: NMTI) have announced that the first patients have been randomized in its pivotal patent foramen ovale (PFO)/migraine trial in the United States, MIST II. The MIST II trial is designed to evaluate the safety and effectiveness of NMT's BioSTAR® implant technology for the treatment and prevention of migraine headaches in patients with PFO. The randomization took place at the Swedish Medical Center in Seattle, Washington. The trial currently is being conducted at more than 25 sites across the country.

Stewart Tepper, MD and Mark Reisman, MD are the co-principal investigators of the MIST II clinical trial. Dr. Tepper is Director of The New England Center for Headache in Stamford, Connecticut. Dr. Reisman is Director of Cardiovascular Research at Swedish Medical Center, Seattle, Washington. Doctors Reisman and Amish Desai of the Swedish Medical Center were involved in the randomization.

"MIST II is a landmark trial that will advance the collective understanding within the medical community of the potential link between PFO and migraine headaches," said Dr. Reisman. "The patients enrolled in MIST II will benefit from the only clinical trial which utilizes a device made of bioabsorbable collagen matrix material designed to promote closure of structural heart defects, such as PFO. In addition, MIST II is supported by evidence from a predicate PFO/migraine study (MIST) and several retrospective studies at various medical centers throughout the world."

"Randomizing the first patients in the MIST II trial is an important clinical milestone for us," said President and Chief Executive Officer John E. Ahern. "While it has taken longer to reach this point than we had anticipated, it was time well-spent and we are enthusiastic about the prospects for this comprehensive trial. In order to ensure statistically relevant results, we developed a thorough screening process to include only patients that would benefit most from PFO treatment."

A PFO is a common heart defect that may be a potential risk factor for migraine headaches in some patients. The PFO allows venous blood, unfiltered and unmanaged by the lungs, to enter the arterial blood circulation. The unfiltered venous blood may contain elements that can trigger migraines in some patients.

MIST II is a prospective, randomized, multi-center, controlled study. The double-blinded trial is designed to randomize approximately 600 migraine patients with a PFO to either PFO closure with NMT's implant technology or a control arm. More than 50 leading migraine headache specialists and interventional cardiologists are participating in MIST II.

As mentioned, patients enrolled in MIST II will receive the world's first bioabsorbable implant, BioSTAR®. As reported in NMT's BEST (BioSTAR® Evaluation STudy) trial, BioSTAR® achieved a post-implant complete closure rate of 92% at 30 days and 96% at six months. Over time, 90% to 95% of the BioSTAR® implant is absorbed and replaced with the patient's native tissue providing a more natural, biological closure of their PFO. BioSTAR® is currently available for commercial use in Europe and Canada.

About NMT Medical, Inc.

NMT Medical is an advanced medical technology company that designs, develops, manufactures and markets proprietary implant technologies that allow interventional cardiologists to treat structural heart disease through minimally invasive, catheter-based procedures. NMT Medical is currently investigating the potential connection between a common heart defect that allows a right to left shunt or flow of blood through a defect like a patent foramen ovale (PFO) and brain attacks such as migraine headaches, embolic stroke and transient ischemic attacks (TIAs). A common right to left shunt can allow venous blood, unfiltered and unmanaged by the lungs, to enter the arterial circulation of the brain, possibly triggering a cerebral event or brain attack. More than 25,000 PFOs have been treated globally with NMT's minimally invasive, catheter-based implant technology.

The prevalence of migraines in the United States is about 10%. Of the 28 million migraine sufferers in America, those who experience aura and have a PFO may represent a three million patient subset. Stroke is the third leading cause of death in the United States and the leading cause of disability in adults. Each year, 750,000 Americans suffer a new or recurrent stroke and an additional 500,000 Americans experience a TIA.

This press release contains "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995. Such forward-looking statements - including statements regarding the MIST II and BEST trials, the Company's BioSTAR® programs, regulatory approvals for the Company's products in the United States, Europe and elsewhere abroad, and the Company's investment in product development - involve known and unknown risks, uncertainties or other factors that may cause actual results, performance or achievements of the Company to be materially different from any future results, performance or achievements expressed or implied by such forward-looking statements. Factors that may cause such a difference include, but are not limited to, the Company's ability to develop and commercialize new products, a potential delay in the regulatory process with the U.S. Food and Drug Administration and foreign regulatory agencies, as well as risk factors discussed under the heading "Risk Factors" included in the Company's Annual Report on Form 10-K for the year ended December 31, 2006, Quarterly Report on Form 10-Q for the period ended June 30, 2007 and subsequent filings with the U.S. Securities and Exchange Commission.

For more information about NMT Medical, please visit nmtmedical.