Title : TCD HITS and infective endocarditis: Illustrative case report and series
Abstract:
Introduction: Infective endocarditis (IE) has a high risk of neurovascular complications, including ischemic and hemorrhagic stroke from septic emboli, and mycotic aneurysms. Treatment of this condition requires antibiotics and often valve replacement surgery, however the optimal timing for surgery is complicated by concomitant strokes and risk of hemorrhagic conversion with heparinization during the procedure. Transcranial doppler (TCD) studies assessing for high intensity transient signals (HITS) can detect ongoing microemboli. Here we present an illustrative case report and describe a series of patients with stroke from IE and TCD HITS studies.
Case report: A male patient in his 3rd decade of life with history of IV drug use presented with acute ischemic right MCA stroke (Figure 1A) and fever, not a candidate for acute intervention. CTA showed a right distal M2/M3 occlusion, no mycotic aneurysms identified. He was started on antibiotics daptomycin and ceftaroline with infectious disease consulted, had a transthoracic echo with a 1.5 x 0.75 cm2 mitral valve vegetation. He had a TCD HITS study on hospital day 6 which showed a right MCA HITS (Figure 1B). The following day, a stroke code was activated for unresponsiveness, CT head with hemorrhagic right MCA stroke with IVH and midline shift (Figure 1C). The patient progressed to brain death on hospital day 13.
Methods: Retrospective chart review; 41 patients at to our institution with IE and stroke who had TCD HITS studies for 30 minutes for their stroke work up were included.
Results: Of the 41 patients with TCD HITS studies, 14.6% (6/41) has positive HITS. Of those patients 87.8%(36/41) had ischemic strokes and 19.5% (8/41) died.
Conclusion: TCD HITS studies are non-invasive imaging tests that can detect ongoing septic emboli for patients with IE. In a previous case series of 26 IE patient with TCDs, only 4 had 30 minute studies and only one had microemboli1. In our cohort, of the 41 patients with TCD HITS studies, 14.6% has positive HITS. Of those, 87.8% had further strokes and 19.5% died. TCD HITS has the potential to identify high risk IE patients and to change management in these patients by with antibiotics and guiding surgical timing, hopefully to improve outcomes. More research is necessary.
