Microwave
treatments for enlarged Prostate cause Blood
Pressure surges
Newswise — Many men who
receive microwave therapy for enlarged
prostates experience significant surges in
blood pressure that could raise their risk
of a heart attack or stroke, according to
new research findings published recently in
Mayo Clinic Proceedings.
The Mayo Clinic-led
study of 185 consecutive patients who
received transurethral microwave therapy at
four medical centers found that 42 percent
experienced systolic blood pressure surges
of more than 30 mm Hg, while 5 percent had
surges of more than 70 mm Hg.
“Men who are candidates
for this minimally invasive microwave
therapy tend also to be at higher risk for
cardiac events,” says Lance Mynderse, M.D.,
the Mayo Clinic urologist who authored the
study.
“Blood pressure surges
of the magnitude identified in this study
are troubling side effects of treatment that
need to be monitored and managed.”
Benign prostatic
hyperplasia (BPH), or an enlarged prostate
gland, is a condition affecting half of men
over age 50 and 80 percent of those over 70.
Symptoms include difficult urination, sudden
urges to urinate and inability to empty the
bladder.
BPH often is treated
with medication and in severe cases open
surgery may be necessary, but since 1997
transurethral microwave therapy has been a
less-invasive option.
Transurethral microwave
therapy involves using a catheter to place a
microwave device within the prostate, which
is then heated to destroy excess tissue.
Approximately 70,000 such procedures are
performed each year, usually in an office
setting and typically involving patients
from 50 to 85 years old.
“This patient
population is at high risk of cardiovascular
disease,” explains Benjamin Larson, a
medical student at Cleveland Clinic who is
the lead author of the Mayo Clinic
Proceedings paper.
“Anecdotal reports of
adverse blood pressure events during and
after transurethral microwave therapy, and
our own experience, led us to look back at
the records to identify potential problems
among these patients whose blood pressure
had been monitored.”
The authors say the
study findings should not necessarily deter
physicians and their patients from using one
of the six FDA-approved devices for
transurethral microwave therapy, but they
should take reasonable precautions given the
strong possibility of blood pressure surges.
“Blood pressure
monitoring should be a standard part of the
procedure. Blood pressure readings should be
taken throughout the procedure, multiple
times. Unfortunately, that has not always
been the practice for this office-based
therapy,” Dr. Mynderse explains.
“Monitoring will enable
physicians to identify the problem and
adjust treatment. Patients also should be
encouraged to continue their
anti-hypertensive medications, particularly
beta blockers, as they prepare for the
procedure.”
Besides Larson and Dr.
Mynderse, other authors of the paper include
Thayne Larson, M.D.; Virend Somers, M.D.,
Ph.D.; Michael Jaff, D.O. and William Evans,
D.O.
A peer-review journal,
Mayo Clinic Proceedings publishes original
articles, reviews and editorials dealing
with clinical and laboratory medicine,
clinical research, basic science research
and clinical epidemiology.
Mayo Clinic Proceedings
is published monthly by Mayo Foundation for
Medical Education and Research as part of
its commitment to the medical education of
physicians. The journal has been published
for more than 80 years and has a circulation
of 130,000 nationally and internationally.
Articles are available online at
http://www.mayoclinicproceedings.com.
