It is well known that cardiovascular disease and related vascular risk factors are associated with cognitive decline and worse brain health outcomes among aging adults. Recently, subtle age-related changes in cardiac hemodynamics have been proposed as an emerging risk factor for abnormal brain aging, even in the absence of cardiovascular disease. Changes in cardiac function, vital for determining the total amount of blood available for perfusing the body, and arterial stiffness, important for regulating blood flow delivery, have been associated with compromised brain structure and function among older adults. Such alterations in cardiac output and arterial stiffening may directly affect brain health through blood-brain barrier breakdown or oligemia or may interact with Alzheimer disease and concomitant pathologies common in aging adults to accelerate cognitive decline. This review examines how age-related alterations in cardiovascular integrity contribute to abnormal brain aging, emphasizing that changes in systemic hemodynamics may compromise brain health before or concurrently with the development of neurodegenerative processes that are common in aging.