University of Minnesota Medical School, Minneapolis, Minnesota, United States.
Karolinska Institute, Stockholm, Sweden.
Physiol Rev. 2025 Jan 1;105(1):209-266. doi: 10.1152/physrev.00007.2024. Epub 2024 Aug 15.
Syncope is a symptom in which transient loss of consciousness occurs as a consequence of a self-limited, spontaneously terminating period of cerebral hypoperfusion. Many circulatory disturbances (e.g. brady- or tachyarrhythmias, reflex cardioinhibition-vasodepression-hypotension) may trigger a syncope or near-syncope episode, and identifying the cause(s) is often challenging. Some syncope may involve multiple etiologies operating in concert, whereas in other cases multiple syncope events may be due to various differing causes at different times. In this communication, we address the current understanding of the principal contributors to syncope pathophysiology including examination of the manner in which concepts evolved, an overview of factors that constitute consciousness and loss of consciousness, and aspects of neurovascular control and communication that are impacted by cerebral hypoperfusion leading to syncope. Emphasis focuses on ) current understanding of the way transient systemic hypotension impacts brain blood flow and brain function; ) the complexity and temporal sequence of vascular, humoral, and cardiac factors that may accompany the most common causes of syncope; ) the range of circumstances and disease states that may lead to syncope; and ) clinical features associated with syncope and in particular the reflex syncope syndromes.
晕厥是一种症状，表现为短暂的意识丧失，是由于脑灌注短暂受限、自主终止引起的。许多循环障碍（如心动过缓或心动过速、反射性心脏抑制-血管舒张-低血压）可能引发晕厥或近似晕厥发作，识别病因通常具有挑战性。一些晕厥可能涉及多种协同作用的病因，而在其他情况下，多次晕厥事件可能是由于不同时间的不同原因所致。在本通讯中，我们讨论了目前对晕厥病理生理学主要因素的理解，包括检查概念演变的方式、意识和意识丧失的构成因素概述，以及神经血管控制和交流方面的内容，这些方面会因导致晕厥的脑灌注减少而受到影响。重点是：）目前对短暂性全身性低血压如何影响脑血流和脑功能的理解；）伴随晕厥最常见病因的血管、体液和心脏因素的复杂性和时间顺序；）可能导致晕厥的各种情况和疾病状态；以及）与晕厥相关的临床特征，特别是反射性晕厥综合征。
