University of Ottawa, Canada
Keynote: J Neurol Neurophysiol
Background: While oral anticoagulation (OAC) is universally indicated for patients with mechanical heart valves (MHVs), the time for OAC reinitiation following anticoagulant-associated intracerebral hemorrhage (ICH) is uncertain. We sought to determine the optimal timing for restarting the OAC and the associated clinical outcomes in patients with MHVs following ICH. Furthermore, we surveyed the practice preferences of North American neurosurgeons and thrombosis experts on optimal timing of restarting the OAC in this particular group of patients. Methods: We performed a systematic review and a meta-analysis of studies published from January 1950 to April 2014. Medline (Ovid), Embase, Scopus, the Cochrane Library, the Cochrane Controlled Trials Register, LILACS, Web of Science and Global Health were searched for studies reporting the time for re-initiation of OAC in patients with MHV following ICH. Extracted data was on the type of initial ICH, use of cranial surgery, presence of atrial fibrillation, type of MHV, position of MHV, number of MHVs, and timing of OAC re-initiation. In addition, the criteria for study selection included data on valve thrombosis, thromboembolic events or ICH recurrence data, calculated absolute risks, and assessing the effect of anticoagulant resumption timing on ICH recurrence via meta-regression. A cross-sectional survey was disseminated to North American members of the American Association of Neurological Surgeons and the International Society for Thrombosis and Haemostasis. Demographic factors, as well as a clinical scenario with 14 modifiable clinical risk factors were included in the survey. Results: 23 case-series and case-reports were identified and meta-regression was done. Overall proportion of ICH recurrence was 13% (95% confidence interval [CI], 7% ΓΆΒ?Β? 25%), while valve thrombosis and ischemic strokes occurred at 7% (95% CI, 3% - 17%) and 12% (95% CI, 5% - 23%), respectively. A trend towards lower ICH recurrence was observed with delayed OAC re-initiation (slope estimate -0.2154, p=0.10). Recurrence rate ranged from 50% with OAC re-initiation at 3 days to 0% with re-initiation at 16 days. 504 physicians completed our survey (response rate= 34.3%). Majority of participants were affiliated with academic centers, and managed ΓΆΒ?Β¤ 10 ICH patients with MHV per year. There was wide distribution in response on optimal timing for OAC re-initiation following an ICH: 59% and 60% preferred to re-start OAC between 3 and 14 days following the hemorrhagic event (median = 6-7 days). Smaller hemorrhages (<30cm2), CHADS2 score ΓΆΒ?Β¥2, concomitant venous thromboembolism, mitral valve prosthesis, caged-ball valves and multiple valves prompted earlier OAC re-initiation. Conclusion: From our meta-analysis restarting OAC in day 4 seems to be associated with low risk of recurrent ICH or valve thrombosis, however this conclusion is limited by the quality of the studies. We support the urgent need for high-quality randomized studies in this population. Moreover, based on our collected survey data, there is a wide variation in the current practice of neurosurgeons and thrombosis specialists when they encounter patients with ICH and MHV, though decisions were influenced by patient- and valve-related factors. As our observed variation likely reflects the immense gap in current evidence, prospective randomized trials in this population are therefore urgently needed.
AlKherayf is an Associate Professor and a Neurosurgeon at University of Ottawa. He is also a neuroscientist at the Ottawa Hospital Research Institute (OHRI) with a cross appointment to the Clinical Epidemiology Program. He is the Director of the Clinical Research Program at the Division of Neurosurgery at the Ottawa Hospital, and the Director of Spine Fellowship Program at University of Ottawa. After graduating from medical school he completed his neurosurgery training at University of Ottawa in 2010. He also completed two fellowships in complex spine surgery and minimally invasive skull base surgery. Additionally, he has training in clinical epidemiology and biostatistics (MSc, Epidemiology and Biostatistics 2011) and has completed the Clinician Investigator Program certified by the Royall College of Physician and Surgeons of Canada (RCPSC). His clinical practice is focused on complex spine surgery, minimally invasive cranial surgery and complex cranio-cervical reconstruction. His clinical research interests lie on translational primary brain tumor research, clinical trials, and spinal cord injury. He has authored and co-authored many research papers and abstracts, and spoken at many international conferences. Hehas special interest in neurosurgery and spine education by directing many training courses. He also has been serving as an editorial board member of many journals.