I think your interpretation is correct, no conclusion can be drawn from the results of this study.
If a similar study were repeated and adequately powered, I wouldn’t consider it p-hacking. The larger sample should only decrease the uncertainty in the primary outcome. P-hacking would be like if they set out to measure like 20 different outcomes to see if some turn out to be statistically significant by pure chance.
As an aside, I think it might be hard to gather enough participants for an adequately powered study given how close the outcomes were in this study. I’m no cardiac surgeon, but I think mechanical heart valves are generally less favored compared with bioprosthetics. Furthermore, the addition of aspirin to warfarin may cut down the number of participants as well, as aspirin is not routinely recommended.
I think your interpretation is correct, no conclusion can be drawn from the results of this study.
If a similar study were repeated and adequately powered, I wouldn’t consider it p-hacking. The larger sample should only decrease the uncertainty in the primary outcome. P-hacking would be like if they set out to measure like 20 different outcomes to see if some turn out to be statistically significant by pure chance.
As an aside, I think it might be hard to gather enough participants for an adequately powered study given how close the outcomes were in this study. I’m no cardiac surgeon, but I think mechanical heart valves are generally less favored compared with bioprosthetics. Furthermore, the addition of aspirin to warfarin may cut down the number of participants as well, as aspirin is not routinely recommended.