Infective endocarditis occurs in 1.7 – 6.2 per 100,000 people per year in the United States and Europe. The in-hospital mortality rate is 18-23 percent; the 6 month mortality rate is 22 – 27%.
A stroke will affect 16-25% of those patients with endocarditis and staphylococcus is associated with higher rate of complications when compared to other pathogens. Also, vegetations over 10mm increased the risk of embolism.
In a recent study published in Neurology, researches wanted to determine when the patient diagnosed with endocarditis was no longer at an increased risk for stroke.
Previous studies estimated that it can range from one month before the diagnosis all the way up to one month after antibiotics were started.
The study identified patients hospitalized with infective endocarditis from July 2007 – June 2011. Among 17,926 patients with infective endocarditis, 2,275 developed a stroke up to 12 months after the diagnosis was established.
From these patients, 1,877 had an ischemic stroke, 312 had a hemorrhagic stroke, and 86 had both an ischemic and hemorrhagic stroke.
Stroke risk was highest (9.1%) one month after the diagnosis of endocarditis. But, the overall risk was increased 4 months before the diagnosis up to 5 months after the diagnosis of endocarditis.
This study shows that the patient might be an increased risk for stroke for a lot longer than previously imagined.
Patient outcomes after neurological complications vary and it’s estimated that only 30% of those affected by stroke will have a full neurological recovery.
Remember, aspirin or anticoagulation therapy does not reduce the risk of stroke. There are other indications to use anti-thrombotic therapy if the benefits outweigh the risk. Antimicrobials seem to start to reduce the risk of embolism weeks after they are started.
Antibiotics are usually given for 6 weeks. Typically vancomycin and gentamicin are given empirically until cultures return.