(PHILADELPHIA) - Clinical researchers at the University
of Pennsylvania Health System are starting a trial
utilizing a new mechanism to treat the heart when its electrical
pulses essentially short-circuit, referred to as atrial fibrillation
The biggest problem physicians run into with current therapies
to cope with electrical rhythmic pumping problems in the heart,
namely pulmonary vein isolation procedures, is that up until now,
they’ve had to deliver the energy bursts to the tissue in
a dot-by-dot catheter ablation procedure around the veins, almost
like a string of pearls. “That can cause swelling, and when
that swelling goes down, you may still have viable tissue left behind,
gaps, where the electricity can still conduct itself or get through,”
Callans, MD, director of the electrophysiology
laboratory at the Hospital
of the University of Pennsylvania
and principal investigator of this study. “Now we have
a mechanism to construct this barricade of lesions, to do an entire
circular ablation, minimizing the potential for gaps behind in the
electrophysiologists at Penn are now using a high intensity focused
ultrasound (HIFU) ablation system. It’s the first to deliver
energy bursts forward in a complete circle, all at once, from outside
of the vein. This invasive procedure is done in the lab with balloon
catheters while the patient is awake but sedated.
Electrophysiologists use ablation procedures (involving intense
heat on the area of the heart causing the rhythmic pumping problems)
to turn pulmonary vein tissue into scar tissue so that it can no
longer conduct electricity. When this is done in several locations,
it can effectively stop the symptoms of atrial fibrillation, which
affects as many as five million Americans. “Since this new
system sits outside of the vein, and delivers energy forward rather
than immediately around it, there is no damage to the inside of
the vein. This maintains a normal blood flow. Plus, this new system
could shorten the ablation procedure time which currently takes
about four hours,” adds Callans.
Penn -- which is the only trial site in Pennsylvania, and one of
15 nationally -- is now recruiting volunteers for the HIFU ablation
system trial. If you’re interested in participating, call
(21) 662-6052. This is a randomized trial in which some participants
will receive ablation treatment with the HIFU system made by ProRhythm,
Inc., while others will be treated with anti-arrhythmic medication.
The patients in this trial must be symptomatic and the atrial fibrillation
must start and stop on its own (it is not persistent).
Penn Medicine, which has one of the largest cardiac electrophysiology
programs in the country, has been doing atrial fibrillation ablation
procedures for the last several years. Callans states, "Ablation
is definitely the future for treatment of atrial fibrillation. Everything
else we currently use to treat A-Fib is flawed. So the ablation
procedure itself has to improve, become more effective and safer.
And one way we can do this is on the technology front by developing
better tools. This trial may be a big part of that."
PENN Medicine is a $2.9 billion enterprise
dedicated to the related missions of medical education, biomedical
research, and high-quality patient care. PENN Medicine consists
of the University of Pennsylvania School of Medicine (founded in
1765 as the nation's first medical school) and the University of
Pennsylvania Health System.
Penn's School of Medicine is ranked #2 in the nation for receipt
of NIH research funds; and ranked #3 in the nation in U.S. News
& World Report's most recent ranking of top research-oriented
medical schools. Supporting 1,400 fulltime faculty and 700 students,
the School of Medicine is recognized worldwide for its superior
education and training of the next generation of physician-scientists
and leaders of academic medicine.
The University of Pennsylvania Health System includes three hospitals,
all of which have received numerous national patient-care honors [Hospital
of the University of Pennsylvania; Pennsylvania Hospital, the nation's
first hospital; and Penn Presbyterian Medical Center]; a faculty practice
plan; a primary-care provider network; two multispecialty satellite
facilities; and home care and hospice.