Vasovagal syncope: Difference between revisions

no edit summary
No edit summary
No edit summary
Line 1: Line 1:
==Different types of vasovagal syncope==
* [[Young patients]]
* [[Young patients]]
* [[Old patients]]
* [[Old patients]]
Line 4: Line 5:
* [[Blood phobia]]
* [[Blood phobia]]
* [[Blood donation]]
* [[Blood donation]]
* [[Vasovagal syncope during sleep]]


=Triggers for Vasovagal Syncope=
=Triggers for Vasovagal Syncope=
Line 21: Line 23:


<br>
<br>
==Post-exercise vasovagal syncope==
Syncope after exercise is often neurally mediated, i.e. post-exercise vasovagal syncope. This condition is typically diagnosed in '''young fit, furthermore healthy young patients.''' 
Foremost, the diagnostic workup of all patients presenting with exercise-related syncope is aimed at '''excluding dangerous [[Cardiac syncope|cardiac conditions]]''' and includes echocardiography and exercise testing <cite>Krediet04b</cite>. Risk factors for a cardial problem are fainting while sitting or supine and suddenly fainting ''during'' exercise without presyncope.
<br>
Characteristically, syncope may occur while the individual is '''standing motionless''' during the first five to ten minutes after exercise <cite>Bjurstedt</cite>. Especially athletes in the (ultra) endurance sports are at risk for post exercise vasovagal syncope e.g. after marathon swimming <cite>Finlay</cite> or marathon running <cite>Tsutsumi</cite><cite>Holtzhausen95</cite><cite>Holtzhausen97</cite>.
Vasovagal syncope after routine treadmill testing is rare (estimated 0,2% <cite>Schlesinger</cite>). However, when treadmill testing is immediately followed by passive head-up tilt testing, this percentage can increase up to 50-70% <cite>Bjurstedt</cite>.
Vasovagal syncope after exercise is considered to be a benign occurrence <cite>Krediet04b</cite>.
===Muscle pump===
During exercise, rhythmically contracting skeletal muscles in the lower part of the body reduce the degree of venous pooling by squeezing veins, thereby increasing the venous return of blood to the heart. This phenomenon is known as the ‘muscle pump. The sudden removal of the muscle pump after stopping exercise decreases cardiac preload which, together with a rapid return of vagal tone, may promote vasovagal syncope.


<br>
<br>