A 57-year-old man presents to the Emergency Department with palpitations for the past 36 hours. He has no past history of note. There is no associated chest pain or shortness of breath. Clinical examination is unremarkable other than an irregular tachycardia. An ECG shows atrial fibrillation at a rate of 126 bpm with no other changes.
What is the most appropriate management?
Correct Answer C: This patient is a good example of someone who would benefit from electrical cardioversion.
Atrial fibrillation: cardioversion:
Onset < 48 hours: If the atrial fibrillation (AF) is definitely of less than 48 hours onset patients should be heparinized. Patients who have risk factors for ischaemic stroke should be put on lifelong oral anti-coagulation. Otherwise, patients may be cardioverted using either:
Following electrical cardioversion if AF is confirmed as being less than 48 hours duration then further anti-coagulation is unnecessary.
Onset > 48 hours: If the patient has been in AF for more than 48 hours then anti-coagulation should be given for at least 3 weeks prior to cardioversion. An alternative strategy is to perform a transoesophageal echo (TOE) to exclude a left atrial appendage (LAA) thrombus. If excluded patients may be heparinized and cardioverted immediately.
If there is a high risk of cardioversion failure (e.g. Previous failure or AF recurrence) then it is recommend to have at least 4 weeks amiodarone or sotalol prior to electrical cardioversion Following electrical cardioversion patients should be anticoagulated for at least 4 weeks. After this time decisions about anti-coagulation should be taken on an individual basis depending on the risk of recurrence.
A 35-year-old female presents with a deep vein thrombosis in the third trimester of pregnancy. Whilst in the Emergency Department she develops a left hemiparesis.
What underlying cardiac abnormality is most likely to be responsible?
Correct Answer C: Whilst atrial septal defects may allow emboli to pass from the right side of the heart to the left side, the most common cause is a patent foramen ovale.
Patent foramen ovale:
Patent foramen ovale (PFO) is present in around 20% of the population. It may allow embolus (e.g. from DVT) to pass from right side of the heart to the left side leading to a stroke - 'a paradoxical embolus'.
There also appears to be an association between migraine and PFO. Some studies have reported improvement in migraine symptoms following closure of the PFO.
A 71-year-old patient presents to the Emergency Department with a two hour history of crushing central chest pain. He is known to have a history of ischaemic heart disease. The ECG shows the following:
Where is the lesion most likely to be?
Correct Answer B: These are classical findings of a circumflex occlusion. The table below shows how the changes correspond to the cardiac anatomy:
ECG: coronary territories: The table below shows the correlation between ECG changes and coronary territories:
A 72-year-old man is admitted to the Emergency Department with chest pain. On initial assessment he is noted to be pale, have a heart rate of 40/min and a blood pressure of 90/60 mmHg.
Which one of the coronary arteries is most likely to be affected?
Correct Answer C: Complete heart block following a MI? - right coronary artery lesion.
This patient has developed complete heart block secondary to a right coronary artery (RCA) infarction. The atrioventricular node is supplied by the posterior interventricular artery, which in the majority of patients is a branch of the right coronary artery. In the remainder of patients the posterior interventricular artery is supplied by the left circumflex artery.
Complete heart block: Features:
A 1-year-old girl is noted to have a continuous murmur, loudest at the left sternal edge. She is not cyanosed. A diagnosis of patent ductus arteriosus is suspected.
What pulse abnormality is most associated with this condition?
Correct Answer A: Patent ductus arteriosus -> collapsing pulse.
Patent ductus arteriosus: Overview:
Features:
Management:
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