You can find out how good your doctor is by how long or whether s/he ever tells you about this study. Good luck.
http://www.medpagetoday.com/Cardiology/Strokes/54184?
Long-term follow-up of the RESPECT trial continued to show no overall
outcome advantage of patent foramen ovale (PFO) closure, although the
procedure did pan out for reducing recurrent cryptogenic strokes,
particularly for younger adults.
With an addition of about 2.5 years of follow-up on average, risk of
all-cause strokes was no different for patients who had PFO closure with
the investigative Amplatzer device than for those on medical management
alone (P=0.16), John D. Carroll, MD, of the University of Colorado Denver, and colleagues found.
Because other
components of the primary composite endpoint -- recurrent nonfatal
ischemic stroke, fatal ischemic stroke, or early death after
randomization -- were likewise no different between treatment arms,
the conclusion was the same as in the main intent-to-treat result at an average of 3 years of follow-up.
"This is a study that started in 2003 and there have been a lot of
lessons learned," Carroll said, adding, "Things we learned over the 10
years were not all recurrent events are going to be due to paradoxical
embolism, and when one out of five patients are now over the age of 60,
we cannot look at PFO closure as curative."
But he pointed to side analyses that suggested the device did what it should have been expected to do.
For example, there was a 54% relative reduction in recurrent
cryptogenic stroke in the PFO closure group in the intent-to-treat
analysis compared with medical management group in long-term follow-up (P=0.042).
Looking just at patients with a device in place versus those who
never got a device in the trial, the relative reduction was 70% (P=0.004), Carroll noted. Eleven percent of the control group sought off-study PFO closure at some point.
In sensitivity
analysis, people under age 60 had a 52% relative risk reduction of any
recurrent stroke in the intent-to-treat analysis, which was significant (P=0.035).
One-third of the recurrent strokes had a known mechanism that PFO
closure would not have been able to prevent, from things like small
vessel disease, cardioembolism from endocarditis, and atrial
fibrillation.
During extended follow-up, one in five patients who reached the
over-60 age group were excluded from the trial in the initial enrollment
criteria, because of the higher likelihood of other confounding
etiologies for stroke with older age.
"In those patients who have recurrent strokes that were not PFO
mediated and had a separate mechanism, it really stresses another
important take-home message...that there has to be attention to
modification of other stroke risk factors," Carroll told reporters at a
press conference.
Carroll reported the findings at a late-breaking clinical trial presentation at the Transcatheter Cardiovascular Therapeutics (TCT) meeting in San Francisco.
And
for the 620 patients with substantial shunts or atrial-septal
abnormalities, the benefit of PFO closure in preventing recurrent
cryptogenic stroke was also significant in the intent-to-treat analysis
(hazard ratio 0.245, P=0.007).
However, extended follow-up out to an average of 5.5 years in the PFO
occluder arm and 4.9 years in the medical management arm included a
declining proportion of patients as follow-up went on, noted press
conference discussion panelist Roxana Mehran, MD,
of Mount Sinai School of Medicine in New York City. "By the second or
third year...your number at risk is half of the original population. And
then when you get out to 10 years, you're down to 15 patients or so."
And considering that the initial intent-to-treat results were
negative, the subgroup results have to be taken "with a grain of salt,"
she argued. "There's no question the curves are separating, and it's
good to see that. And I do believe that those patients in the original
subgroup with a significant shunt and the atrial-septal aneurysm are
probably the best patients to think about for sure for recurrent
cryptogenic stroke."
Carroll responded that there were still almost 600 patients being
followed at 4 or 5 years and that this is probably the best evidence
that will become available. "We're never going to have a trial like this
again in terms of such extensive follow-up of so many patients."
There is another trial coming -- the REDUCE trial with a different PFO closure device -- though with a somewhat more modest 664 patients and 24-month primary endpoint.
While all the panel
said, via a hand-raising vote, that they were convinced by the data for
specific subgroups and would want the device themselves in such a
circumstance, FDA approval will be a challenge with such data, predicted
press conference moderator and conference co-director Ajay J. Kirtane, MD.
With such a low event rate in RESPECT, 600 out of almost 900 "doesn't
really pass muster for most clinical trials in terms of follow-up,"
said Kirtane, of New York-Presbyterian Hospital/Columbia University
Medical Center in New York City.
On the other hand, "this device looks incredibly safe," said panelist Howard C. Herrmann, MD, of the University of Pennsylvania in Philadelphia.
In adjudicated safety findings, there were no intra-procedure strokes
and no cases of device embolism, thrombosis, or erosion. The rates of
major vascular complications and device explant were "very low" at 0.9%
and 0.4%, respectively.
The deep vein thrombosis or pulmonary embolism rate was higher with
the PFO occluder than with medical management (0.61 versus 0.12 per 100
patient-years).
The difference was of
"unclear significance" because of no association with procedure or
access site, lack of thrombophilia evaluation in the trial, and
allowance of warfarin use in the medical management group. Also, Carroll
noted, the difference could have been due to differential follow-up as
more participants dropped out in the medical management group.
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