Rationale: The posterior circulation represents 20% of blood supply to the brain, and its occlusion, commonly by embolism, causes brainstem, cerebellar, and lower cerebral infarctions. The clinical presentation varies from mild symptoms to severe neurological deficits or death. The duration of intervention is vital, commonly with antithrombotic drugs or through intervention. Patient concerns: The first case was a 36-year-old-female admitted due to snakebite. On admission, she developed acute kidney injury, sepsis, and compartment syndrome, for which she underwent fasciotomy, improved, and was discharged. Two days later, she presented with sudden onset of left-sided weakness. The second was an 85-year-old male with hypertension and end-stage renal disease on regular hemodialysis who presented with high-grade continuous fever associated with rigor, confusion, and decreased level of consciousness for 2 days. The third case was a 30-year-old woman admitted to the emergency department because of an abrupt loss of consciousness that occurred when she was going to the bathroom; she was unable to speak, swallow, or move her limbs. There was no fever, sphincteric disturbance, or seizure. She had a history of severe chronic bifrontal headache that started 4 months prior to elective cesarean section. Diagnosis: The patients were diagnosed as top of basilar artery infarction. Interventions: The first patient received enoxaparin, intravenous fluids, proton-pump inhibitors, antibiotics, and rivaroxaban. The second patient received intravenous antibiotics, dual antiplatelet therapy, enoxaparin, blood transfusions, and frequent hemodialysis sessions. The third patient received intravenous fluids, antibiotics, and oral anticoagulants (rivaroxaban 15 mg twice daily for 2 weeks then 20 mg once daily). Outcomes: The 3 patients were discharged following pharmacological treatment. The first and third cases showed improvement in their symptoms. However, the second patient developed bilateral epistaxis and bleeding after medication and did not show improvement in his symptoms; however, he died due to intradialytic hypotension. Lessons: We reported 3 Sudanese patients who had complicated medical sequelae due to top basilar artery occlusion, received anticoagulants and supportive therapy, and showed variable recovery over weeks, with the exception of 1 patient who died after follow-up.

An atrial septal aneurysm (ASA) is saccular defect of the atrial septum, and it may be associated with congenital heart disease. Cryptogenic strokes are strokes of unknown origins, and ASA may be one of these causes. In this case report, we described a cryptogenic stroke in an adult Sudanese female with interatrial septal aneurysm.