Edwards Lifesciences Corporation announced that new research demonstrates that using its minimally invasive PORT ACCESS System in mitral valve surgery significantly decreases the length of stay in hospitals and intensive care units (ICU), and improves other outcomes when compared to conventional sternotomy (an incision the length of the chest). Results were presented at the Society for Heart Valve Disease 5th Biennial Meeting in Berlin.

The data show statistically significant patient benefits, as well as the potential for reducing hospital costs associated with lengthy stays and certain complications, when using the PORT ACCESS System in mitral valve surgery, said the study’s lead author, William H. Ryan, M.D., a cardiac surgeon with Cardiopulmonary Research Science and Technology Institute, Dallas, TX; Medical City Dallas Hospital, Dallas, TX; and the Heart Hospital Baylor, Plano, TX. Dr. Ryan provides paid consulting services to Edwards Lifesciences as an educator and trainer for PORT ACCESS surgery.

For mitral valve repair, PORT ACCESS surgery demonstrated substantial reductions in hospital days, ICU stay, ventilation time and return to OR for post-op bleeding, Ryan continued.

Among the study’s statistically significant findings:

The 171 patients undergoing mitral valve repair with the PORT ACCESS

System had total hospital stays approximately 1.5 days less than sternotomy patients (p < 0.001). In these patients, ICU stay was reduced from 82 hours to 44 hours (p < 0.001), a 46 percent reduction.

In the same population, the number of patients requiring post-operative ventilation was reduced from 75.6 percent in the sternotomy group to 50.3 percent in the PORT ACCESS group (p < 0.001). Further, substantially fewer PORT ACCESS patients required prolonged ventilation (defined by the Society of Thoracic Surgeons, or STS, as greater than 24 hours): 5.4 percent compared to 11.8 percent with full sternotomy (p=0.039).

Trends in the mitral valve replacement data supported the findings in the repair cohort, but due to a smaller patient population size (n=42), statistical significance was not achieved for as many endpoints. One exception was the 64 percent reduction in ICU length of stay from 147 hours in the sternotomy group to 53 hours in the PORT ACCESS group (p=0.016).

Ryan and his co-authors, including William T. Brinkman, M.D., conducted a retrospective review of outcomes from matched patient groups at a single center undergoing mitral valve repair or replacement with either a full sternotomy or the PORT ACCESS approach through a mini-thoracotomy (an average incision of 4.1 cm in length). Patients who were not candidates for PORT ACCESS surgery, primarily due to their vasculature, were screened out. Data were extracted from the researchers’ STS-certified, audited database between January 1996 and November 2008.

The full research has been accepted for publication later this year. A similar analysis of aortic valve replacement and repair procedures was conducted and is expected to be presented at the Southern Thoracic Surgical Association meeting in November 2009.