OSCE medical Flashcards
What are the types of AF?
There are three types of AF: paroxysmal, persistent and long-term persistent.
• Paroxysmal AF - symptoms start suddenly and resolves by itself within 7 days of no treatment. (episode may last even a few seconds only). Anticoags may still be prescribed to prevent stroke.
• Persistent AF - episodes are continuous and last more than 7 days. Beta blockers and calcium channel blockers are usually prescribed to slow down the heart rate (rate control). Cardioversion and ablation may also be offered.
Long term persistent AF (permanent AF) - This is the term given when medication, catheter ablation and cardioversion do not work. It is resistant to treatment. This is called long-term persistent AF and doctor and pt usually agree to still receive rate control and anticoag meds.
What medications are used for AF?
The aims of treatment for those with AF are to
1. Reduce the risk of stroke
2. Control any symptoms of AF
The need for coagulation is calculated using CHA2DS2-VAS score:
HASBLED score is used to identify the risk of a major bleed. Use this tool to also identify if the risks of anticoags outweigh the benefits.
Management of stroke risk is same no matter what AF you have since research suggests that stroke risk is the same even if you have paroxysmal AF vs permanent AF. If the cause of paroxysmal AF is not due to modifiable factors such as excessive alcohol or energy drink use (caffeine) then consider treatment.
Warfarin and Dabigatran are anticoags that are commonly used in NZ.
Rate and rhythm control is also used, where we lean more towards rate control due to simpler medicine regimens. (they both equally prevent strokes). However rhythm control can be used when AF causes HF or symptomatic paroxysmal attacks.
First line is a beta blocker (OTHER THAN SOTALOL (this can cause arrythmias)). E.g. metropolol,
A calcium channel blocker that one can use (say if they have asthma) are diltiazem or verapamil (BUT NOT IN PTS WITH less than 40% left ejection fraction (HF) due to negative inotropic effects (less strong contractions))
What is the CHADSVAS score?
Congestive heart failure HTN Age over 75 (2) Diabetes Stroke/TIA (2) Vascular disease Age over 65 Sex (female)
What are the investigations you need to order to diagnose AF?
- ECG - can show any causes for the AF such as MI or left ventricular hypertrophy. The QT interval may also need to be assessed before starting some medications
- Bloods - TSH to exclude hyperthyroidism, LFTs to exclude excessive alcohol use and prior to starting anticoags, FBC to exclude anaemia and infection as a contributor to AF, electrolytes to exclude any metabolic abnormalities, HbA1c to exclude diabetes as cause
- Echo - this is used to assess thrombolytic risk in those with poor LV function and which calcium channel blocker to use.
Sometimes with paroxysmal AF can use a holter monitor.
What are the differentials for palpitations?
- AF
- Anxiety/panic attack
- Hyperthyroidism related hypermetabolic state
- VT
Excessive alcohol or caffeine use
How to differentiate between types of cyanosis?
Peripheral cyanosis causes cold blue hands
Central cyanosis causes blue lips and tongue and when sever can cause blue hands but this is usually warm.
What are some causes of central cyanosis?
• Hypoxic lung disease
• Cyanotic congenital heart disease such as a right to left cardiac shunt.
Methaemalbuminaemia - caused by intravascular hemolysis.
What are some causes of peripheral cyanosis?
- Raynaud’s syndrome
- Peripheral vascular disease
- Heart failure
- Shock
What are the differentials for an irregularly irregular pulse and how to identify which?
• AF
• Ventricular ectopic beats (VEB’s)
• Complete HB with ventricular escape beats
To differentiate between AF and VEB’s you can do an ECG and look for sinus rhythm. And for vebs there will be random qrs complexes not necessarily followed after a p wave. If there is no ECG available, you can exercise the pt and if the irregularly irregular pulse dissapears it is VEB, if it doesn’t it is AF.
What are causes of AF?
• Excessive alcohol
• Previous mi
• Rheumatic heart disease
PE/pneumonia
Causes of absent radial pulse?
• Congential (usually bilaterally)
• Artherosclerotic disease in subclavian artery
Previous artery line
coarctation of the aorta
What are some causes of a non-palpable apex beat?
• Something in between your hand and the heart - fat (obese pt), air (pneumothorax), fluid (pleural effusion, hemothorax, pericardial effusion)
The apex is not in its normal position - displaced usually in LHF, or dextrocardia
What are the 5 causes of cardiac failure?
- Pump failure - ischemaic heart disease, cardiomyopathy, constrictive pericarditis, arrythmia, negative inotropes/chronotropes.
- Excessive preload - regurgitant valvular disease (MR/AR), volume overload (IV fluids, renal failure)
- Excessive afterload - AS, HTN
- Isolated RHF - cor pulmonale which is secondary to chronic lung disease, pulmonary HTN (primarye.g. COPD/due to MS)
- High output cardiac failure (which is rare) - due to pregnancy, anemia or hyperthyroidism.
What are things you may see on CXR for a person with LHF?
A. Alveolar edema B. Kerley B lines C. Cardiomegaly D. Upper lobe venous Diversion E.Pleural Effusion
What are some causes of pericarditis?
• Viral (coxsackie) • Bacterial/fungal infection • Post MI • Dressler's syndrome (2-10 weeks post MI) • Malignancy SLE/RA/scelroderma
How to describe a heart murmur?
TIP PQRS Timing Intensity Position hear loudest Position that you put patient in that you heard it loudest Quality Radiation to carotids? Systemic features - other stuff like water-hammer pulse etc.
Example of describing AS
• Ejection systolic murmur
• Heard loudest over aortic area
• Radiates to carotid arteries
• Loudest on expiration and sitting forward
• Slow rising pulse with narrow pulse pressure
Non-displaced, heaving apex beat (if present indicates left ventricular hypertrophy)
Example of describing AR
Decrescendo early diastolic murmur
Heard loudest at left sternal edge (the direction that turbulent blood flows) – sometimes heard loudest over the aortic area
Collapsing pulse (i.e. water hammer pulse with wide pulse pressure)
Displaced, hyperdynamic apex beat
Example of describing MR
Pansystolic murmur
Heard loudest over mitral area
Radiates to axilla
Heard loudest using the bell of the stethoscope
Loudest on expiration in the left lateral decubitus position
Displaced, hyperdynamic apex beat
Example of describing MS
Low-pitched, rumbling mid-diastolic murmur with an opening click (click heard in mid-diastole when the mitral valve opens)
Heard loudest over the apex
Loudest in left lateral decubitus position on expiration
Low-volume pulse which may be irregularly, irregular (atrial fibrillation is common in mitral stenosis)
Malar flush
Right sternal heave
What are some causes of cranial nerve palsy?
• Diabetes bc of microangiopathy of the vasa nevorum • Stroke • SLE • Sarcoidosis • Tumour • MS Vasculitis
What are some differentials for CN I palsy?
• Trauma (base of skull fracture)
• Front lobe tumour
Meningitis
What are some differentials for CN II palsy?
Monocular blindness - MS, giant cell arteritis
Bitemporal hemianopia - pituitary tumour, internal carotid artery aneurysm
Homonymous hemianopia - anything after the optic chiasm, tumour, stroke, abscess
What are some differentials for CN III palsy?
• Partial loss of movement (means with pupils spared) - diabetes because microangiopathy does not affect the parasympathetic nerves.
Complete loss of the CN III - raised intracranial pressure with tentorial herniation and posterioir cerebral artery aneurysm.
What are some differentials for CN IV palsy?
Single palsy is rare. Get pt to look down and see the blood vessel move medially. Likely due to orbit trauma.
What are some causes for CN V palsy?d
• Trigeminal neuralgia
• Acoustic neuroma
Herpes zoster
What are some differentials for CN VI palsy?
Lateral rectus muscle affected.
• Skull fracture involving petrous temporal bone
• Nasopharyngeal carcinoma
Raised intracranial pressure
