New Studies Support CardioFocus HeartLight(TM) Endoscopic Ablation System's Notable Treatment Results for Paroxysmal Atrial Fibrillation

MARLBOROUGH, Massachusetts, May 9, 2011 - — Data Presented at Heart Rhythm 2011 Show Durable Pulmonary Vein
Isolation of 86% –

CardioFocus, Inc., developer of the HeartLight Endoscopic Ablation System
for the transcatheter treatment of Atrial Fibrillation (AF), announced its
technology enables a Pulmonary Vein (PV) acute isolation rate of nearly 99%,
with approximately 86% of PVs remaining persistently isolated after three
months. Additional research also suggests that 65% of patients achieve
durable freedom from AF after a single procedure.

New clinical results supporting the safety and efficacy of the HeartLight
System were presented at Heart Rhythm 2011, the Heart Rhythm Society's 32nd
Annual Scientific Sessions, in San Francisco, CA. The presentations included
data from both a 200-patient international, multicenter clinical experience
with the CardioFocus device (15 sites across four countries) and from a
unique study that employed intracardiac diagnostic remapping on 56 paroxysmal
AF patients, whether or not they were symptomatic, to determine the rate of
persistent PV isolation.

"These recent clinical experiences support the promise of the HeartLight
technology to help patients achieve lasting freedom from paroxysmal AF,"
commented Stephen Sagon, President and CEO of CardioFocus, Inc. "As shown by
the robust data across multiple clinical centers, our proprietary technology,
including endoscopic visualization, a compliant balloon catheter and the
delivery of light energy, is helping to enhance the reproducibility and
efficacy of atrial fibrillation ablation."

In the 200-patient study, titled "Pulmonary Vein Isolation Using the
Visually-Guided Laser Balloon: The First 200-Patient Multicenter Clinical
Experience" and presented on May 6th, researchers reported nearly 99% of all
PVs were isolated following the HeartLight ablation procedure. Of the 107
patients that reached at least 6 months follow-up, 65% remained free from AF
after a single ablation procedure. The procedure also demonstrated low
complication rates including freedom from strokes, PV stenosis or atrial
esophageal fistulae.

"A historical concern with catheter ablation therapy for paroxysmal AF is
the inability to create durable lesions in a single procedure to adequately
isolate the pulmonary veins," said investigator Prof. Karl-Heinz Kuck, MD, of
Krankenhaus St. Georg, Hamburg, Germany. "This study demonstrates that a
higher-than-average rate of PV isolation can be reproducibly achieved across
multiple sites with a visually-guided laser balloon catheter."

The remapping study, presented on May 4th and titled "Persistent
Pulmonary Vein Isolation Using the Visually-Guided Laser Balloon: Results of
a Multicenter PV Remapping Study," revealed that 86% of all PVs were
persistently isolated at three months. The study included 56 paroxysmal AF
patients who underwent initial ablation with the HeartLight catheter at three
centers. After three months nearly all patients were remapped (52),
regardless of symptoms, to determine the incidence of persistent PV
isolation.

"This data is significant because diagnostic remapping to check PV
isolation in asymptomatic patients is rarely attempted. In this case it has
enabled us to clearly confirm quality outcomes, demonstrating that the
visually-guided laser balloon catheter can achieve persistent, long-lasting
PV isolation in patients with paroxysmal AF," said investigator Petr Neuzil,
MD, of Na Homolce Hospital, Prague, Czech Republic.

About CardioFocus, Inc.

CardioFocus, Inc. is a medical device manufacturer dedicated to advancing
ablation treatment for cardiac disorders such as atrial fibrillation (AF).
Its novel HeartLight(TM) Ablation System incorporates a catheter containing
both a micro-endoscope and light energy fibers to give physicians the
capacity to see within the heart, and for the first time, visually direct the
application of laser energy to achieve durable pulmonary vein isolation.

The HeartLight Endoscopic Ablation System received CE Mark in 2009 for
the treatment of atrial fibrillation, and is commercially available at key
institutions throughout Europe. The device is investigational in the U.S.,
with a pivotal study expected to commence in 2011. CardioFocus is
headquartered in Marlborough, MA. For more information on the company and its
technology, please visit www.CardioFocus.com.

The scientific information discussed in this news release is preliminary
and investigative. The CardioFocus Endoscopic Ablation System is not approved
by the U.S. Food and Drug Administration (FDA), and no conclusions can or
should be drawn regarding the safety or effectiveness of the system. Only FDA
can determine whether the product candidates are safe and effective for the
use(s) being investigated. Healthcare professionals should refer to/rely upon
FDA-approved labeling for the products, and not the information discussed in
this news release.

    Company Contact:               Media Contact:
    ----------------               --------------
    Anjie Roldan                   Lisa Cook/Jason Rando
    Vice President Finance         +1-646-536-7012/7025
    +1-508-658-7237                lcook@theruthgroup.com
    aroldan@cardiofocus.com        jrando@theruthgroup.com

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