Experimental syncope has been induced by various means such as the Valsalva maneuver, a combination of hyperventilation and Valsalva, exposure to acceleration on a centrifuge, venipuncture and blood loss, ocular compression, and ventricular arrhythmia but the clinical phenomenology has proven to be consistent, irrespective of the procedure. Whether or not syncope manifests with convulsions depends on the degree of cerebral hypoxia ( 44). In experimental series, they represent the rule rather than the exception. They observed tonic and myoclonic phenomena during syncope in the absence of epileptic EEG activity and coined the term “convulsive syncope."Ĭonvulsions are an integral component of the brain's response to hypoxia. Gastaut and colleagues were the first to conduct studies on the clinical and electroencephalographic features of experimentally induced syncope in human subjects ( 18). A century later, Dell and colleagues demonstrated that motor activation in the early stages of cerebral hypoxia resulted from the combined effects of direct hypoxic activation of the brainstem reticular formation and cortical suppression with subsequent reticular disinhibition ( 11). The term “convulsive syncope” specifies a common variant of syncope that is accompanied by tonic or myoclonic activity.Īnimal experiments on convulsive syncope date back to the middle of the 19th century, when Kussmaul and Tenner showed that anoxic convulsions occur after ablation of the telencephalon but not after destruction of the brainstem ( 11). Syncope is defined as a brief loss of consciousness and upright posture due to global cerebral hypoxia. Specific provocation and rapid reorientation help to distinguish syncope from generalized tonic clonic seizures.Myoclonus is usually brief, arrhythmic, and multifocal.Syncope is often accompanied by tonic or myoclonic muscle activity.An increasingly recognized and treatable cause of syncope is ictal asystole or bradycardia during temporal lobe seizures. ![]() Investigations such as tilt testing or creatine kinase levels may be helpful but are never diagnostic in isolation. Recognition of syncope also depends on accurate information about premonitory symptoms and postictal events. ![]() Differential diagnosis is based on the specific features and not the mere presence or absence of these phenomena. Syncope is commonly accompanied by tonic or myoclonic muscle activity, eye deviations, automatisms, vocalizations, and hallucinations, which may all complicate the distinction from epileptic seizures. 2011 124(24):e783–831.In this article, the author provides an overview of convulsive syncope. 2011 ACCF/AHA Guideline for the diagnosis and treatment of hypertrophic cardiomyopathy: a report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines. Sudden cardiac death and implantable cardioverter-defibrillators. In: Braunwald’s heart disease-textbook of cardiovascular medicine. Current evaluation and management of syncope. Aortic dissection: new frontiers in diagnosis and management, part II: therapeutic management and follow-up. Outcomes of medical management of acute type B aortic dissection. 2014 130:2287–94.Įstrera AL, Miller CC, Safi HJ, Goodrick JS, Keyhanii A, Porat EE, Achouh PE, Meada R, Azizzadeh A, Dhareshwar J, Allaham A. Mortality from thoracic aortic diseases and associations with cardiovascular risk factors. Sidloff D, Choke E, Stather P, Bown M, Thompson J, Sayers R. Aortic dissection: new frontiers in diagnosis and management, part I: from etiology to diagnostic strategies. Advanced Cardiovascular Life Support provider manual. UpToDate, 2015.Īmerican Heart Association. 2010 American heart association guidelines for cardiopulmonary resuscitation and emergency cardiovascular care science. suggests dobutamine for LESS ill patients not the very sickest. Prognosis and treatment of cardiogenic shock complicating acute myocardial infarction. Thirty-year trends (1975–2005) in the magnitude of, management of, and hospital death rates associated with cardiogenic shock in patients with acute myocardial infarction: a population-based perspective. ![]() Goldberg RJ, Spencer F, Gore J, Lessard D, Yarzebski J. National Vital Statistics Report, CDC, 2015 64 (10):1–93.Ĭancer Facts and Figures 2013, American Cancer Society.
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