The oldest old population (>85 years of age) represents the faster growing segment of the elderly in developed countries. Cardioembolic infarction (CI) accounts for 14%-30% of all cerebral infarcts and is the most severe ischemic stroke subtype with the highest in-hospital mortality. Also, CI is associated with a low frequency of symptom-free patients at hospital discharge and presents a non-negligible risk of early embolic recurrence. Moreover, cardioembolic stroke is the acute cerebrovascular event most commonly found in very old subjects. However, some clinical aspects of the natural course of the disease in very old patients are still poorly defined. The present report presents an updated review of relevant aspects of CI related to clinical manifestations, biological characteristics, prognostic implications, and treatment strategies, which may contribute to improving the quality of care and outcome of acute cardioembolic stroke in very old patients. The most relevant aspects of CI are discussed based on the data published in the literature and the authors' experience in the management of stroke patients, collected from the hospital-based "Sagrat Cor Hospital of Barcelona Stroke Registry". The following aspects are commented on: epidemiologic data and risk factors, clinical characteristics, cardiac workup studies, special cardioembolic clinical features, outcome, thrombolytic therapy, antithrombotic treatment, and indications for future research lines. Cardioembolic stroke is an important topic in the frontier between cardiology and vascular neurology. The impact of CI on the patients' health and quality of life, health care systems, and society in general merits an in-depth review of current clinical issues, advances, and controversies.