The PROACT trial did show that it is indeed safe,
actually if you read the details it did not demonstrate that, but don't just take my word for that, read the actual analysis
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6472691/
Comments of my own which are within textual quotes are in italics and encased in braces such as: {
comment}
The authors make some good points and perhaps is one of the better critical assessments of PROACT. About halfway through, they say:
While the PROACT trial was generally well conducted, it raises several important points that warrant consideration. Firstly, the study sample size was calculated to demonstrate non-inferiority of a composite endpoint of bleeding, TE and thrombosis events, which was entirely driven by the reduction in bleeding events in the lower INR group as anticipated.
…
These findings require further analysis to ensure safety of aiming for lower INR targets.
The mean follow-up was 3.8 years and was 98% complete {
so not very long}
The mean INR was 1.89 in the test group and 2.5 in the control group (p < 0.001).{
so about what we target as the bottom end or }
Its worth remembering here that a much longer study of some 4000 patients found that for all valves the average duration of time needed to get a thrombosis event for INR around 1.8 was 4 years. How amusing they chose 3.8 years.
Means are given but not SD The mean INR was 1.89 in the test group and 2.5 in the control group (p < 0.001).
They say:
with no differences in the rates of TE and thrombosis events (2.96%/pt-yr in the test group versus 1.85%/pt-yr in the standard group, p = 0.178)
So why then is nearly double suddenly no differences (and standard group and control group used loosely)? Strangely people seem to ignore that a TE thrombosis even is related to a stroke. New brain cells are presently hard to find.
Then:
.. This is consistent with recently published studies demonstrating the safety of a lower anticoagulation regimen in patients with mechanical AVR
Where they go on to cite
a study which suggests this is actually the case for every other low risk patient with every other type of current bleaflet pyrolytic carbon valve. Sort of saying that “nothing except our marketing makes our valve stand out”
Then:
… Similar to findings from the PROACT trial, there were no differences in TE events (OR 0.33 [0.006–4.20], p = 0.6) while there was a significant decrease in bleeding events in the low-dose group (OR 0.36 [0.11–0.99], p = 0.04).
What is absent here
in the actual PROACT study is any actual age related risk and a comparison to the age related risks of the general population.
Amusingly the claims by Cryolife that there is
no difference in TE are supported by this reference:
https://www.jacc.org/doi/full/10.1016/j.jacc.2018.03.535
…which amusingly would actually suggest over the longer term there is a difference.
So my point is that when a study is sponsored by the valve maker who is after some point of differentiation of their product over another (St Jude for instance) they may actually not lie, but maybe they don't actually reflect the truth properly either.
Again, these are not my opinions, but actual citations from peer reviewed analysis undertaken medical researchers and published in a relevant medical practice journal
We are all entitled to our opinions but your phrase of "contrary to what you may hear here" is perhaps an attempt to dismiss what we say as like a fiction or hearsay. This is not the case.
...and don't worry about the ticking. You won't hear it over that Harley anyway!
fully agree ... I don't hear it on even my quiet bikes
Best Wishes
