Neurally-mediated reflex syncope - Symptoms, Causes, Images, and Treatment Options

Diseases

Highlights & Basics

Key Highlights

Neurally mediated reflex syncope (NMRS) refers to a group of related conditions or scenarios in which symptomatic hypotension occurs as a result of neural reflex vasodilation and/or bradycardia.
Vasovagal syncope (VS) refers to a particular type of NMRS also known as the common faint.
VS has many manifestations and is generally considered to encompass faints triggered by emotional upset, fear, and pain, as well as other less well-defined circumstances.
Patient education is the foundation of treatment for most NMRS syndromes, including VS.
Patients must be informed that, while reflex faints are almost never life-threatening, they tend to recur (often in clusters), and injury can result if preventive measures are not taken seriously.

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Definition

Epidemiology

Etiology

Pathophysiology

Images

Classification of syncope
Ambulatory monitoring recording obtained during a spontaneous faint associated with marked bradycardia. Baseline movement reflects the patient's distress
ECG trace revealing an episode of torsades de pointes in a patient with recurrent faints and evident long-QT syndrome
Initial evaluation and further management strategy of syncope based on European Society of Cardiology Task Force Guidelines. AECG, ambulatory ECG; CSM, carotid sinus massage; EP, electrophysiologic; ILR, implantable loop recorder; SMU, syncope management unit

Citations

Key Articles

Shen WK, Sheldon RS, Benditt DG, et al. 2017 ACC/AHA/HRS guideline for the evaluation and management of patients with syncope: a report of the American College of Cardiology/American Heart Association Task Force on clinical practice guidelines, and the Heart Rhythm Society. Heart Rhythm. 2017 Aug;14(8):e155-217.[Abstract][Full Text]
Brignole M, Moya A, de Lange FJ, et al; ESC Scientific Document Group. 2018 ESC guidelines for the diagnosis and management of syncope. Eur Heart J. 2018 Jun 1;39(21):1883-948.[Abstract][Full Text]
Moya A, Brignole M, Menozzi C, et al; International Study on Syncope of Uncertain Etiology (ISSUE) Investigators. Mechanism of syncope in patients with isolated syncope and in patients with tilt-positive syncope. Circulation. 2001 Sep 11;104(11):1261-7.[Abstract][Full Text]
Sandhu RK, Raj SR, Manlucu J, et al; Primary Writing Committee. Canadian Cardiovascular Society clinical practice update on the assessment and management of syncope. Can J Cardiol. 2020 Aug;36(8):1167-77.[Abstract][Full Text]
Reed MJ, Newby DE, Coull AJ, et al. The ROSE (risk stratification of syncope in the emergency department) study. J Am Coll Cardiol. 2010 Feb 23;55(8):713-21.[Abstract][Full Text]
Benditt DG, Ferguson DW, Grubb BP, et al. Tilt table testing for assessing syncope. American College of Cardiology. J Am Coll Cardiol. 1996 Jul;28(1):263-75.[Abstract]
Raviele A, Giada F, Menozzi C, et al; Vasovagal Syncope and Pacing Trial Investigators. A randomized, double-blind, placebo-controlled study of permanent cardiac pacing for the treatment of recurrent tilt-induced vasovagal syncope. The Vasovagal Syncope and Pacing Trial (SYNPACE). Eur Heart J. 2004 Oct;25(19):1741-8.[Abstract][Full Text]

Referenced Articles

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