Lecture 13 CVD Theme - Faints, Falls and Funny Turns Flashcards
What is syncope thought to be?
When we are bleeding the body drops BP to reduce blood loss - a life saving feature.
In syncope it is thought the body is misunderstanding what is happening and this is why we faint.
Syncope is common and not a disease.
What is syncope and what is it characterised by?
A transient loss of consciousness due to global cerebral hypoperfusion.
Characterised by rapid onset, short duration and complete spontaneous recovery.
What is vasovagal syncope?
VVS is a common faint and a reflex not an illness. Caused by a dramatic sudden drop in heart rate and blood pressure.
>90% of syncope in younger people is vasovagal syncope.
Light headedness, blackouts, yawning, restless, intense heat, nausea, fatigue.
Describe VVS in older people.
Very short or even absent.
Non-specific.
No warning signs.
Describe the Behold-Jarish reflex.
BP drops so there is less venous return to the right side of the heart. Baroreceptors detect a drop in BP and stimulate the sympathetic NS to increase HR and inotropy. This makes the heart beat faster but it does not pump much so there is then a paradoxyl decrease in HR and BP causing a person to faint.
What is carotid sinus syndrome?
Carotid body becomes sensitive with age.
If stimulated it causes a reaction similar to VVS and people present with episodes of collapse and falling.
Happens quickly as once the pressure drops in the carotid body the reaction starts.
Because of the quick onset, people struggle to put their hands out to break falls so can often cause more serious injuries.
Describe orthostatic hypotension.
Moving from a lying down to upright position.
Venous blood in the thorax and abdomen when lying down means the venous blood can return no problem.
As you stand the blood goes quickly to the thighs and pelvis causing a drop in BP and an increase HR and vasoconstriction due to parasympathetic NS activity.
Older people have a stiffer heart and can’t elicit a high HR as well as a younger person so vasoconstriction is reduced as NO route is impaired.
HR also decreased due to a decrease of cells in the SA node.
Can cause dizziness, falls and non-specific low BP symptoms.
Treated the same as VVS.
What is cardiac structural disease and arrhythmia?
Higher mortality rates.
History of heart disease, chest pain, palpitations, little/no pre syncope, abnormal ECG, cardiac medications and syncope while sitting.
Hard to diagnose as people have these intermittently so prolonged CT monitoring required.
Implant under the skin monitors the rhythm and device can tell the implant to remember everything recorded for the past 10-20 minutes post fall and then can be analysed.
Describe the abnormalities seen on ECGs when someone has cardiac structural disease and arrhythmia.
P wave far from Q.
PR interval prolonged - with each beat PR interval gets longer until there is no QRS complex.
What is the tilt table?
Lowers BP with gravity.
Helps explain why older people may be having increased falls, if they report they don’t remember fainting/feeling unwell this is a sign their unexplained falls are due to syncope.
Describe treatment for VVS.
Increase water intake
Salt increase
Caffeine increase or decrease
Decompression socks
Physical counter manoeuvres
Trigger avoidance
Stopping or starting medication
Tilt-training
Pacemaker
