How long do you treat with antibiotics? This is one of the areas of uncertainty especially when we’re
talking about aminoglycosides. It’s difficult to study these patients and the duration. If you can imagine,
somebody might get six weeks of IV antibiotics. Another person might get four. Well, can you enrol
enough patients to tell the difference? You need thousands of patients to tell the difference between
four and six weeks of therapy for example. The other thing is sometimes you’re comparing apples to oranges.
A patient doesn’t have the same valve problem. Some patient has heart failure that others don’t.
So, I think you can see why the duration of antibiotics and especially aminoglycosides is difficult to determine.
Then of course, another area of uncertainty is that appropriate timing of surgery. There is some evidence
that surgery during the first week, there may be an increased incidence of relapse. I would say that
if they have florid heart failure in the first week then the surgeon should go in anyway. But if in general,
early surgery would be after the first week. What about the utility of brain imaging? As I mentioned,
80% of patients are going to have some kind of abnormality that you can see but what to do about it?
How do you manage somebody who’s got say a mycotic aneurysm? You do serial angiography
to document that it resolves. Sometimes these mycotic aneurysms actually resolve during the course
of antibiotic therapy. What about very large, unresolving aneurysms? Probably, we need to do
endovascular treatment but these are still areas of uncertainty. So, with that, I will close
my discussion of infective endocarditis. I hope that it’s been helpful to you.