Interesting that his first reaction was not to look up and review the study that was the basis for the letter from On-x
this point is what I was going to expand on, IIRC (not having got one myself) there was a mention
in fine print that the decision to accept this lower INR value should be taken with the cardiologist and in the light of evidence as to stroke or TIA events. This suggests that a case by case is required (but suggested in a way to not be given the appropriate clarification). One word comes to mind: disingenuous .
On-X themselves in the conduct of the PROACT trial not only had a protocol to examine for this but to then immediately take any lower INR range patients out and put them into the "control" group ... which in proper scientific rigor invalidates the experiment (meaning it should have failed). IE
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6472691/
where they write:
Any patient who experienced a TE event in the study group was crossed over to the standard INR group, though they remained in the test group through an intention-to-treat analysis.
really ... not left there to suffer the actual consequences (as the above case was), and then not taken out of the test group numbers and followed as if they were test group but not treated as test group. Verges on fraud IMO.
Its also worth noting that this above paper is an analysis of the PROACT trial and despite being (I hope) peer reviewed also presents one of the significant issues which I was trained to be triggered by (when doing my masters and studying how to do a critical review of literature): it inserts a lie (
or at the kindest interpretation, a demonstration of deliberate blindness) that fits their own agenda
In contrast, the Ross procedure (pulmonary autograft replacement) alleviates the need for lifelong anticoagulation and is the only operation that guarantees long-term viability of the aortic valve substitute.
Its misinformation because cryo-preserved homograft is at least as good (and doesn't leave you with now two diseased valves). Given that this was published in 2001 its hard to imagine that the "researchers" in the above study did due dilligence on that assertion.
https://pubmed.ncbi.nlm.nih.gov/11380096/
This underscores why critical thinking cap must be on in all readings, because despite the benefits of "peer review"
- peers may share the authors bias
- peer reviewers are busy and only paid about an hours worth or work per review.