Cardiology II Flashcards
Synchronised DC cardioversion aims to deliver a shock with which part of the ECG? [1]
R wave
A patient presents with AF. Describe a clinical sign you might see relating to their radial pulse [1]
Apical to radial pulse deficit occurs as not all atrial impulses (palpable at the apex) are mechanically conducted to the ventricles (palpable as a peripheral pulse)
Where do you place the electrode for V1 on an ECG? [1]
4th intercostal space, right sternal edge
A patient has been admitted last week for infective endocarditis.
They have an ECG performed which shows new onset PR prolongation.
What is the likely diagnosis [1] and treatment? [1]
The newly lengthened PR interval (1st degree heart block) suggests peri-valvular abscess as a complication of infective endocarditis. Abscess is an indication for valve replacement.
Nicorandil is most useful in the management of:
Hypertension
Heart failure
Angina
Atrial fibrillation
Acute coronary syndrome
Nicorandil is most useful in the management of:
Hypertension
Heart failure
Angina
Atrial fibrillation
Acute coronary syndrome
A patient falls and hits their head, investigations reveal SAH.
What ECG would you likely see? [1]
Subarachnoid haemorrhage is a cause of torsdaes de pointes
When is treatment indicated in Mobitz type I? [1]
What is first line? [1]
However, in cases such as this where the patient is symptomatic (typically pre-syncope/syncope, hypotension, bradycardia) and particularly in elderly patients, treatment might be considered, which would primarily consist of transcutaneous pacing.
Mechanical valves - target INR:
aortic: []
mitral: []
Mechanical valves - target INR:
aortic: 3.0
mitral: 3.5
Synchronised DC cardioversion aims to avoid delivering a shock with which part of the ECG? [1]
T wave - risk of causing VF
Describe the treatment used for rhythm control for AF (electrical and pharmological) [3]
DC Cardioversion
- electrical stimulation to restore sinus rhythm
Amiodarone
- antiarrhythmic drug which can restore sinus rhythm on its own. It is suitable in most patients
Flecainide
- an antiarrhythmic drug that can be used in some patients to restore sinus rhythm, but is contraindicated in those with possible structural or ischaemic heart disease
NICE guidelines (2021) suggest all patients with AF should have rate control as first-line, except in which four instances? [4]
NICE guidelines (2021) suggest all patients with AF should have rate control as first-line, except with:
- A reversible cause for their AF
- New onset atrial fibrillation (within the last 48 hours)
- Heart failure caused by atrial fibrillation
- Symptoms despite being effectively rate controlled
Long-term AF rhythm control is with which drugs? [3]
Beta blockers first-line
Dronedarone second-line for maintaining normal rhythm where patients have had successful cardioversion
Amiodarone is useful in patients with heart failure or left ventricular dysfunction
Describe the process of AVN ablation to treat AF [3]
Atrioventricular node ablation involves destroying the connection between the atria and ventricles (the atrioventricular node)
After the procedure, the irregular electrical activity in the atria cannot pass through to the ventricles
A permanent pacemaker is required to control ventricular contraction
Anticoagulation is still needed to prevent strokes.
Describe the dosing regimen of apixaban and dabigatran compared to edoxaban and rivaroxaban? [2]
Apixaban and dabigatran are taken twice daily
Edoxaban and rivaroxaban are taken once daily.
Describe what is meant by INR with regards to warfarin treatment [1]
The INR (international normalised ratio) is used to assess how anticoagulated the patient is by warfarin.
The INR calculates the patient’s prothrombin time (time to clot) compared with the prothrombin time of an average healthy adult.
An INR of 2 means the patient has a prothrombin time twice that of an average healthy adult (it takes them twice as long to form a blood clot).
Which factors contribute to the CHA2DS2-VASc score? [8]
CHA2DS2-VASc is a mnemonic for the factors that score a point:
C – Congestive heart failure
H – Hypertension
A2 – Age above 75 (scores 2)
D – Diabetes
S2 – Stroke or TIA previously (scores 2)
V – Vascular disease
A – Age 65 – 74
S – Sex (female)
What CHA2DS2-VASc indicates anticoagulation treatment for AF? [3]
(NICE, 2021)
0 – no anticoagulation
1 – consider anticoagulation in men (women automatically score 1)
2+ – offer anticoagulation
NB: Aspirin alone is NOT used for stroke prevention in atrial fibrillation (using aspirin was an option years ago).
The NICE guidelines recommend using the [] score for assessing the risk of major bleeding in patients with atrial fibrillation taking anticoagulation.
The NICE guidelines recommend using the ORBIT score for assessing the risk of major bleeding in patients with atrial fibrillation taking anticoagulation.
Explain the treatment that can be used as an option for those with contraindications to anticoagulation and a high stroke risk [1]
Left atrial appendage occlusion:
- The left atrial appendage is a small pouch in the wall of the left atrium. It is the most common site for a thrombus to form.
- Left atrial appendage occlusion involves inserting a catheter into the femoral vein, feeding that through the venous system to the right atrium and puncturing the septum between the atria to access the left atrium. Then, a plug is placed in the left atrial appendage, preventing blood from entering that area.
What is the difference in when digoxin and CCBs such as verapamil and diltiazem are effective? [2]
Digoxin: only works when at rest (therefore less preferable)
Verapamil and Diltiazem: work at rest and during exercise
Name five side effect of amiodarone use [5]
- Pneumonitis
- Bradycardia and Heart Block
- Hepatitis
- Photosensitivty and grey discolouration
- Thyroid abnormalties (hyper & hypo): amIODarone - iodine in the drug
Descrbe the MoA of digoxin? [2]
How does it specifically work to treat AF or atrial flutter [2]
Negatively chronotropic (decreases HR); but positively inotropic (increases contraction)
In AF & atrial flutter: causes increased vagal (parasympathetic tone) - reducing conduction at the AVN
(In HR: inhibits Na/K ATP pumps, causing Na to accumulate in the cells; causing increased Ca2+ intracellularly too - increasing contraction)
In patients presenting acutely with AF, it is first important to perform a clinical assessment (e.g. ABCDE) and determine haemodynamic stability.
If a patient is haemodynamically stable - describe the next stages of treatment
If AF has started within 48hrs of presentation
- Immediate pharmalogical cardioversion
If AF has started in more than 48hrs of presentation:
- Delayed, electrical cardioversion
Consecutive, normally-conducted QRS complexes that alternate in height refers to what ECG phenomona? [1]
What pathology does it suggest? [1]
Electrical alternans - suggests cardiac tamponade
What pathology does this ECG suggest? [1]
Alternating QRS amplitude and axis = electrical alterans - cardiac tamponade
Describe the difference between Atrio-ventricular nodal re-entrant tachycardia (AVNRT)
and Atrio-ventricular re-entrant tachycardia (AVRT)
Atrio-ventricular nodal re-entrant tachycardia (AVNRT):
- Originates from a re-entrant retrograde electrical circuit involving the AV node, resulting in initiation and propagation of a cardiac tachyarrhythmia
- The re-entrant cycle occurs around the AVN
Atrio-ventricular re-entrant tachycardia (AVRT):
- originates via a re-entrant retrograde electrical circuit
- involves an accessory pathway between the atria and the ventricles, rather than the AV node
- This returning pathway causes causes the atria to contract BEFORE the SAN sends out another signal
- Some forms of AVRT may exhibit a Wolff-Parkinson-White pattern
https://www.osmosis.org/learn/Atrioventricular_nodal_reentrant_tachycardia_%28AVNRT%29
What common ECG changes do you see in AVRT? [2]
Pre-excitation:
- Initial slurring of QRS complex: the first part of QRS is less steep due to activation of an accessory pathway
- Reduced PR interval
ADD PHOTO to this from lecture
Describe what happens if you give adenosine to someone with atrial tachycardia (e.g. atrial flutter)
Increases AV block & create more flutter waves
C.f. AVRT & AVNRT which have excitation in the AVN, so adenosine works to treat them
