302 Cardiac investigations Flashcards
What are the pros and cons of a 12 lead ECG?
Pros:
Cheap
Easy to produce
Instant result
Provides important evidence
Cons:
It’s just a snap shot
What are the indications for a 24/48 hour cardiac tape?
-Investigations of palpitations/syncope
-Investigate for presence of silent AF post CVA/TIA
-Patients who complain of daily symptoms
-To classify burden of disease (e.g PVCs)
-To assess chronotropic incompetence
What are the cons of a 24/48 cardiac tape?
-If leads come off then the findings cannot be analysed
-Some patients get a rash to the stickers
-Patient has to carry around the recording device
-Arrhythmia has to occur during period of recording
-Typically 3 lead therefore no information regarding underlying structural or ischaemic abnormalities
What is a Holter Monitor/Event Recorder?
Usually last 7 days but some can last up to 2 weeks
-The recorder will record any irregular heart rhythms but will not record all the data during the period it is worn
-Patients are also able to activate the recording if they are getting symptoms
Indications:
Patients who complain of symptoms on a weekly basis
Cons:
Still have to keep it on for the duration of the period of recording. This may impact on the patients day to day life.
What are the indications for an exercise tolerance test?
-To assess for ischaemic ECG changes on exercise (only done if the coronary anatomy is known)
-Assessment of cardiovascular risk e.g. evidence of symptoms in asymptomatic severe valve disease or evidence of arrhythmias in structural heart disease (HCM)
-Assess chronotropic incompetence
-Fitness to practice for certain occupations
How is an exercise tolerance test done?
-The patient will be asked to exercise (usually treadmill but some units have bikes) at an incremental level and will have their ECG and BP continuously measured
-Patients need to be motivated to reach maximal effort for useful results
What are the pros and cons of an exercise tolerance test?
Pros:
-Dynamic testing of symptoms with ECG monitoring
-Any urgent findings flagged up on the day
Cons:
-Patient has to be mobile
-Some medications such as beta blockers can cause false negative results
-Not sensitive if the coronary anatomy is not known especially in female patients therefore no longer part of guidance for detection of chest pain
What is an Implantable loop recorder (ILR)?
A devise inserted to measure the electrical activity of the heart
Indications: Infrequent episodes of symptoms associated with tachy/bradyarrythmias
How is an ILR inserted?
Local anaesthetic is infiltrated into subcutaneous tissue
Device is inserted
Wound is glued or suture close
Device remains in situ for 3 year
What are the pros and cons of an ILR?
Pros:
-Long term monitoring
-Continuously records and will alert the cardiac physiologist if concerning arrhythmias are received
Cons:
-Invasive
-More expensive
-Very small risk of infection
-Need second procedure to remove
