Intracranial hemorrhage (ICH) is a devastating neurologic event. One form of ICH is hemorrhagic transformation of ischemic stroke (HT), which typically occurs in the days immediately following the infarct. HT often results in neurologic deficits, long-term disability, or death. It is unknown whether all types of ICH share common risk factors. The ability to predict who is at highest risk for HT and ICH is important to clinicians, particularly when considering treatment with anticoagulation, a common occurrence given the increasing frequency of patients with atrial fibrillation, blood clots, and mechanical valves. Anticoagulation itself likely increases risk of HT, making this group a potentially high-risk patient population. Until recently, no clinical tool existed to accurately estimate risk. Using a retrospective cohort of inpatients with acute stroke with an indication for anticoagulation, we found that age, infarct volume, and renal impairment are important predictors of HT. We created a Hemorrhage Risk Stratification (HeRS) score using these factors, specifically for the inpatient population, to allow physicians to quickly and accurately predict their patient’s individual risk of hemorrhagic conversion. This is useful not only to inform the clinical team and the patient of the expected risk, but also to guide treatment decisions. The HeRS score has been prospectively validated in a unique prospectively recruited inpatient cohort.

In collaboration with information technologist Peter Dziedzic, we have created an application available on iTunes that allows for quick and easy calculation of a patient’s HeRS score. The score provides a clinically useful and quantifiable risk estimate for hemorrhagic transformation in patients warranting anticoagulation, and may be used to guide treatment decisions when the need for anticoagulation is less clear.

In-App Screenshots



  1. Marsh EB, Llinas RH, Schneider ALC, Hillis AE, Lawrence E, Dziedzic P, Gottesman RF. Predicting hemorrhagic transformation of acute ischemic stroke: prospective validation of the HeRS score. Medicine 2016;25:e2430. Click to read article
  2. Marsh EB, Gottesman RF, Hillis AE, Maygers J, Lawrence E, Llinas RH. Predicting symptomatic intracerebral hemorrhage versus lacunar disease in patients with longstanding hypertension. Stroke 2014:45(6);1679-1683. Click to read article
  3. Kaplan EH, Gottesman RF, Llinas RH, Marsh, EB. The association between specific substances of abuse and subcortical intracerebral hemorrhage versus ischemic lacunar infarction. Frontiers in Neurology, 2014;5:174. Click to read article
  4. Marsh EB, Llinas RH, Hillis AE, Gottesman RF. Hemorrhagic transformation in patients with acute ischemic stroke and an indication for anticoagulation. European Journal of Neurology 2013;20(6):962-967. Click to read article
  5. Marsh EB, Gottesman RF, Hillis AE, Urrutia VC, Llinas RH. Serum creatinine may indicate risk of symptomatic intracranial hemorrhage after IV tPA. Medicine 2013;92(6):317-323. Click to read article