Cerebral blood flow cessation time and syncope – Cardiology MCQ – Answer

A sudden cessation of cerebral blood flow of — seconds causes syncope:

Correct answer: b) 6-8 seconds

A fall of systolic blood pressure to 50–60 mmHg at the level of the heart, which corresponds to 30–45 mmHg at the level of the brain in the upright position can also cause syncope with complete loss of consciousness.

Syncope is defined as transient loss of consciousness due to cerebral hypoperfusion, which has a rapid onset, short duration and complete recovery.

Reference

1. Brignole M, Moya A, de Lange FJ, Deharo JC, Elliott PM, Fanciulli A, Fedorowski A, Furlan R, Kenny RA, Martín A, Probst V, Reed MJ, Rice CP, Sutton R, Ungar A, van Dijk JG; ESC Scientific Document Group. 2018 ESC Guidelines for the diagnosis and management of syncope. Eur Heart J. 2018 Jun 1;39(21):1883-1948.

Back to question