Knowledge Gaps and Future Research Cardiac tumors are rare, and systematic research has been limited to case series, leaving gaps in our under- standing and opportunities for future research. Most cardiac tumors are found incidentally, car- rying the threat of stroke or recurrent stroke, and open heart surgery is the only established treat- ment option. Better understanding of the risk modification from antiplatelet or anticoagulation in particular tumor subtypes or morphologies may provide alternative therapeutic options for patients. Specifically, pooled experiences including national and multi-institutional data sets may allow a better understanding of tumor subtypes, fractionation by morphology, and natural history. As technology advances, minimally invasive and percutaneous treatment strategies should be inves- tigated. Similarly, advances in imaging technology will allow greater delineation of tumor subtypes and morphologies. The prognostic implications of these findings should be investigated. Recommendations for Dissection Referenced studies that support recommendations are summarized in online Data Supplements 43 and 44. COR LOE Recommendations In patients with ischemic stroke or TIA after an extracranial carotid or vertebral arterial dis- section, treatment with antithrombotic therapy for at least 3 months is indicated to prevent recurrent stroke or TIA. In patients with ischemic stroke or TIA who are <3 months after an extracranial carotid or vertebral arterial dissection, it is reasonable to use either aspirin or warfarin to prevent recur- rent stroke or TIA.593,594 In patients with stroke or TIA and extracranial carotid or vertebral artery dissection who have recurrent events despite antithrombotic therapy, endovascular therapy may be consid- ered to prevent recurrent stroke or TIA.595,596 Synopsis Extracranial carotid or vertebral dissections can be the result of trauma or spontaneous. 