MOUNTAIN VIEW, Calif., – September 3, 2008 – Hansen Medical, Inc., (Nasdaq:
HNSN) the global leader in flexible robotics and the developer of robotic technology for
accurate 3D control of catheter movement, announced today that a team of physicians
led by Professor Nick Cheshire at St. Mary’s Hospital, part of the Imperial College
Healthcare NHS Trust, in London, England, utilized Hansen Medical’s Sensei™ Robotic
Catheter System and Artisan™ Control Catheter to aid deployment of stent grafts used
to treat an abdominal aortic aneurysm in a 78-year old patient. This procedure is
believed to be the world’s first in which any robotic medical technology has been used
to repair an aortic aneurysm through a patient’s vascular system.

“We have always believed vascular surgery would provide a very natural application for
our Sensei and Artisan robotic technology, and the recent advancement at St. Mary’s
Hospital demonstrates what is already within reach for our technology in this field,” said
Fred Moll, M.D., co-founder and Chief Executive Officer of Hansen Medical. “Just as
important, the recent experience of clinicians at St. Mary’s Hospital clearly
demonstrates what physicians can accomplish when they use Hansen Medical’s
advanced technology to provide more precise movement and control during different
types of surgery.”

“The time taken to correctly position a stent graft during the treatment of an aneurysm is
highly variable and depends on the complexity of the vascular anatomy,” explained
Professor Nick Cheshire. “By providing increased catheter stability and accurate
navigation, the Sensei system has the potential to greatly simplify the procedure and
make it more predictable. In this case, it only took a few minutes to drive the Artisan
catheter to the location where the stent was to be deployed.”

The aorta is the largest artery in the human body. An abdominal aortic aneurysm
results from weakening and swelling of the artery’s walls, often as people age, and is
frequently fatal if it ruptures. When positioned across the weakened section, stent
grafts act as scaffolding that can help prevent the aneurysm from bursting. This surgery
was performed through accessing the patient’s vascular system at the groin and using
Hansen Medical’s Sensei system to accurately navigate the Artisan catheter up into the
weakened section of the aorta, where the stent grafts were placed.

About Hansen Medical, Inc.
Hansen Medical, Inc., based in Mountain View, Calif., develops products and
technology using robotics for the accurate positioning, manipulation and control of
catheters and catheter-based technologies. Its first product, the Sensei Robotic
Catheter system, is a robotic navigation system that enables clinicians to place mapping
catheters in hard-to-reach anatomical locations within the heart easily, accurately and
with stability during complex cardiac arrhythmia procedures. The Sensei system is
compatible with fluoroscopy, ultrasound, 3D surface map and patient electrocardiogram
data and was cleared by the U.S. Food and Drug Administration (FDA) in May 2007 for
manipulation and control of certain mapping catheters in Electrophysiology (EP)
procedures. The safety and effectiveness of the Sensei system for use with cardiac
ablation catheters in the treatment of cardiac arrhythmias, including atrial fibrillation, and
for use in the treatment of any type of vascular disease, have not been established in
the United States. In the European Union, the Sensei system and Artisan catheter are
intended to facilitate medical procedures within the atria of the heart using percutaneous
catheters introduced through the vascular system. Additional information can be found
at www.hansenmedical.com.