Cardiology Quiz | Practice MCQ #mcq.ImBooz

• (A) The patient should be considered for genetic testing
• (B) The patient’s daughter should be considered for genetic testing
• (C) An ICD is likely to be the safest option
• (D) If her daughter has a normal ECG she can be reassured that she does not have long QT syndrome

Check AnswerSolution[A]:- A. An increasing number of genes have been identified for the long QT syndrome but approximately 80% of patients have a mutation of one of three genes (LQT1�3). It is always best to perform genetic tests on the subject who has the clearest case of the condition. In this case, this is the patient herself. If a culprit gene can be found, the process of screening family members becomes much simpler.

• (A) He needs an ICD
• (B) He needs an urgent revascularization
• (C) He needs an EP study
• (D) He tolerated his tachycardia well; therefore it is likely to be an SVT with aberrancy

Check AnswerSolution[A]:- T his man is very likely to have sustained ventricular tachycardia (VT) given his history of ischaemic heart disease, impaired ejection fraction, and broad complex tachycardia. The fact that he has tolerated it well is not an indication that it is an SVT, although this is possible. Therefore an ICD is indicated by NICE criteria as he has an EF <35%, sustained VT, ischaemic aetiology, and NYHA class III or less. It should be noted that this is a secondary prevention indication despite the fact the patient does not appear to have been compromised by his VT. NICE recommends a VT stimulation study for non-sustained VT (NSVT) and EF <35%, but the patient already meets criteria for an ICD and therefore this would be a redundant investigation. Flecainide is contraindicated in patients with established IHD or structural heart disease.

• (A) A. She will need to stop driving for 6 months
• (B) B. She will need to stop driving for 1 month
• (C) C. If she has an appropriate shock she will need to stop driving for 6 months
• (D) E. B and C

Check AnswerSolution[D]:- T he ICD would be a primary prevention device and therefore the patient needs to stop driving for 1 month (compared with 6 months for a secondary prevention device). However, if she has an appropriate shock it is then treated in the same way as a device implanted for secondary prevention and requires 6 months off driving.

• (A) P waves seen ‘walking through the tachycardia’
• (B) The QRS duration shortens as the patient goes from sinus rhythm to tachycardia
• (C) Capture beats
• (D) A right bundle branch block pattern with a small R wave and a large R’ wave(i.e. rsR’) in V1

Check AnswerSolution[D]:- P waves walking through the tachycardia and capture beats are evidence of independent P-wave activity and ‘prove’ that the rhythm is VT. If the QRS is broad in sinus rhythm, it indicates pre-existing conduction tissue disease which will not shorten if the tachycardia is an SVT. Therefore shortening of the QRS proves that the rhythm is VT, probably originating from the septum to give a relatively narrow QRS. Negative concordance shows that the rhythm is originating from the apex of the heart and is therefore VT. The rsR’ pattern is seen in typical RBBB and is suggestive of aberrancy rather than VT, although this is not diagnostic.

• (A) He should be referred for primary angioplasty
• (B) His temperature may have exacerbated his ECG changes
• (C) He should be treated with ajmaline
• (D) He needs an ICD

Check AnswerSolution[B]:- T his ECG is highly suggestive of Brugada syndrome with a type 1 pattern, i.e. >2 mm ST elevation in the J point, downsloping ST elevation, and inverted T waves best seen inlead V2. The ECG changes can certainly be brought about by fevers, and therefore B is the correct answer. There is no description of syncope and therefore the patient does not meet the criteria for considering an ICD. Ajmaline is not a treatment for Brugada! It is a test for people with type 2 or type 3 Brugada pattern on ECG to provoke a type 1 pattern, but should not be given to people who already have a type 1 pattern as it may provoke dangerous arrhythmias. There is no well-established medical therapy for Brugada syndrome although trials with quinidine are under way.

• (A) Family history of sudden cardiac death
• (B) Non-sustained VT on cardiac monitoring
• (C) LV septal thickness of 2.3cm
• (D) Drop in blood pressure on ETT

Check AnswerSolution[C]:- A septal thickness of >3 cm is considered a high-risk marker. All the other factors are high-risk markers.

• (A) IV adenosine
• (B) IV amiodarone
• (C) IV beta-blocker
• (D) Urgent cardioversion

Check AnswerSolution[D]:- S ee the answer to question 8 of this chapter for more details.

• (A) AF with aberrancy
• (B) AF with pre-excitation
• (C) VT
• (D) AVNT-orthodromic

Check AnswerSolution[B]:- T he clue to this ECG is the irregular nature of the QRS complexes, although this can be difficult to detect at fast heart rates. AF with aberrancy would also be possible with an irregular rhythm, but this would have a more typical bundle branch block appearance. In a compromised patient with very short RR intervals and broad QRS complexes, pre-excited AF should be presumed. Drugs that block the AV node should be avoided in pre-excited AF as they are ineffective because fast conduction is across the pathway. Drugs which are negatively inotropic, such as calcium-channel blockers and beta-blockers can also lead to worsening haemodynamics and even death and therefore are contraindicated. Intravenous flecainide could be considered as it will slow conduction across the pathway, but this patient’s heart is going very fast with symptoms and a low BP, and therefore urgent DC cardioversion should be performed in ED resuscitation.

• (A) Amiodarone
• (B) Erythromycin
• (C) Carbemazpine
• (D) Clozapine

Check AnswerSolution[C]:- T he other drugs mentioned are all well known to cause QT prolongation and should be avoided in people with long QT syndrome. Sometimes this is difficult and a risk�benefit decision needs to be made. A full list of drugs known to cause QT prolongation can be found at http://QTdrugs.org.

• (A) An inappropriate shock for AF
• (B) Inappropriate ATP for AF
• (C) Appropriate shock for VT
• (D) Appropriate ATP for VT

Check AnswerSolution[D]:- T his is a single-chamber ICD and therefore there is no information from the atrium. At the beginning of the trace the RR intervals are irregular and relatively long (none are less than 400 ms). This is due to underlying AF. There is then a sudden increase to a regular tachycardia with a cycle length of 300 ms (rate 200 bpm) which is entirely consistent with VT. There are 18 of these beats before the device appropriately detects VT, marked with the word detection appearing at time point 0. The giveaway that ATP is delivered is the word ‘Burst’ being documented, but it can also be seen that 8 beats occur at a slightly shorter RR interval than the VT before the successful termination of the VT and a return to AF with a slower irregular RR interval. These 8 beats are the ATP being delivered. It is important to scrutinize all the information on the programmer printouts carefully as each manufacturer gives the information in a different format.

• (A) The diagnosis can be confirmed on the basis of MRI findings alone
• (B) All patients with a confirmed diagnosis will need an ICD
• (C) It is normally autosomal dominant
• (D) Genetic tests are positive in most cases

Check AnswerSolution[C]:- T o confirm the diagnosis two major, one major and two minor, or four minor criteria are needed, and therefore a diagnosis cannot be made solely on cardiac MRI. Asymptomatic patients with mild disease do not require an ICD. The condition is usually autosomal dominant, but currently genes are only identified in approximately 30% of cases.

• (A) According to NICE criteria he does not qualify for an ICD as his aetiology is not IHD
• (B) He should receive a biventricular ICD
• (C) He should receive a standard ICD
• (D) He should be commenced on oral amiodarone

Check AnswerSolution[C]:- NICE criteria regarding the need for the aetiology to be IHD only apply in the primary prevention setting, but this case describes the need for secondary prevention. The patient’s QRS is narrow; therefore a biventricular pacemaker is not indicated at present and it should be possible to programme the device so that pacing is not needed. The ICD will attempt to treat the monomorphic VT with ATP in this patient, and if this is successful there may well be no need to consider further suppression of VT with either medication or ablation.

• (A) This ECG shows right bundle branch block
• (B) He is asymptomatic and can be reassured without further investigation
• (C) He should have a 5 day monitor and as long as there are no significant arrhythmias orchanges in the QRS complexes he can be reassured and discharged
• (D) He should proceed to an EP study

Check AnswerSolution[D]:- T he ECG shows pre-excitation. Even though the patient is asymptomatic there is a risk of SCD due to pre-excited AF. There is no consensus on the best way to risk stratify patients, but if non-invasive testing is preferred a 5-day monitor could be performed. However, its main use is to see whether the pathway is intermittent with a sudden lossof pre-excitation which would place the patient in a lower risk category. In answer C there is no loss of pre-excitation during the 5-day monitor and therefore it would not be reasonable simply to discharge him. EP studies allow risk stratification and then the possibility of ablating a high-risk pathway at the same time.

• (A) AF with pre-existing RBBB
• (B) AVNRT with aberrancy
• (C) VT-likely to arise from the left ventricle
• (D) VT-likely to arise from the right ventricle

Check AnswerSolution[C]:- T his ECG shows a regular broad complex tachycardia. It has several features of VT with an unusual morphology for RBBB, an axis of �90�, and positivity in aVR. The 12th beat is a fusion beat which clinches the diagnosis. The fact that this is ‘RBBB-like’ suggests that it arises from the left ventricle and then crosses over to the right ventricle in a way that is analogous to conduction in RBBB.

• (A) He has had an appropriate shock for VF
• (B) He has had VF appropriately terminated with ATP
• (C) He has had VT appropriately terminated with ATP
• (D) He has had an inappropriate shock

Check AnswerSolution[A]:- T his is a single-chamber device and it is important not to become confused and think that the top trace is from an atrial lead and that the diagnosis is AF. The rate is very fast and irregular with a chaotic morphology demonstrating VF. ATP would have been unsuccessful, but a further clue that this was a shock comes from the notation 24.9J at the bottom of the strip at the point the shock was delivered. Different manufacturers’ interrogation strips can look quite different but close scrutiny of all the information can often give the answer.

• (A) High-dose aspirin
• (B) Warfarin
• (C) Aspirin and warfarin
• (D) Aspirin or warfarin

Check AnswerSolution[B]:- T his man has a CHADS2 score of 1 (one point for diabetes) and therefore could be offered warfarin or aspirin thromboprophylaxis according to this risk stratification system. However, if the newer CHA2DS2-VASc system is used, he has a score of 3 ( one point for each of DM, age 65�74, and previous MI) and should be offered oral anticoagulation (warfarin or newer agents). A CHA2DS2-VASc score of zero is truly low risk and could be managed with no thromboprophylaxis at all or aspirin (no thromboprophylaxis preferable). A CHA2DS2-VASc score of 1 could be managed with aspirin or oral anticoagulation (the latter is preferable). A score ?2 should be managed with oral anticoagulation. In summary oral anticoagulation is preferred to aspirin in AF patients with one or more stroke risk factors based on the CHA2DS2-VASc score. In the absence of recent ACS or coronary artery stenting, there is no good evidence for either warfarin or antiplatelet drugs.

• (A) IV adenosine
• (B) IV flecainide
• (C) Oral beta-blocker
• (D) IV beta-blocker

Check AnswerSolution[B]:- T his man may have an accessory pathway with rapidly conducted AF. Adenosine, digoxin, verapamil, and beta-blockers should all be avoided as they prolong the AV node refractory period and thus may increase conduction down an accessory pathway. This increases the risk of rapidly conducted AF becoming VF. Intravenous class I antiarrhythmic drugs (e.g. procainamide, flecainide, propafenone) can be used as well as amiodarone, but DC cardioversion is the treatment of choice if there is haemodynamic compromise or rapidly conducted AF down an accessory pathway.

• (A) ACE inhibitors
• (B) Beta-blockers
• (C) Calcium-channel antagonists
• (D) Diuretics

Check AnswerSolution[A]:- ACE inhibitors and ARBs have antifibrillatory and antifibrotic properties. A meta-analysis has shown that ACE inhibitors and angiotensin-receptor blockers (ARBs) reduce the relative risk of incident AF by 25%. The LIFE study, in particular, showed a 33% reduction in new-onset AF in patients with LVH treated with losartan compared with those treated with atenolol.

• (A) She needs to be warfarinized for at least 48 hours pre-cardioversion
• (B) Anticoagulation should be continued after successful cardioversion for at least 4 weeks
• (C) If a TOE rules out atrial thrombus, no anticoagulation is required post-procedure
• (D) Anticoagulation is not required prior to chemical cardioversion

Check AnswerSolution[B]:- Patients should be anticoagulated with a therapeutic INR (>2) for at least 3 weeks prior to cardioversion. Anticoagulation should be continued for at least 4 weeks post-cardioversion as ‘atrial stunning’ may occur. Anticoagulation is required prior to both chemical and electrical cardioverison. If a patient has not had oral anticoagulation for at least 3 weeks, it is reasonable to perform DC cardioversion if a TOE rules out left atrialthrombus. However, LMWH should be commenced prior to a TOE-guided cardioversion and continued post-cardioversion until the target INR is reached with oral anticoagulation.

• (A) It is more effective than amiodarone in maintaining sinus rhythm
• (B) It has no effect on heart (ventricular) rate during AF episodes
• (C) It is contraindicated in NYHA class IV heart failure patients
• (D) It is suitable for her as she is diabetic and aged over 70

Check AnswerSolution[C]:- T his woman appears to be in NYHA class IV heart failure and thus dronedarone is contraindicated according to NICE guidelines. Dronedarone is a structural analogue of amiodarone, but does not contain iodine and thus has a lower risk of skin, lung, and eye side effects. The ATHENA study showed a 24% relative risk reduction of the combined endpoint of cardiovascular hospitalization and death compared with placebo (mainly driven by a reduction in cardiovascular hospitalizations, especially for AF). Dronedarone was also found to reduce the ventricular rate response during AF by 10�15 bpm. Dronedarone is contraindicated in NYHA class III�IV heart failure but is recommended by NICE as an option in patients whose AF is not controlled by first-line therapy and who have at least one of the following risk factors: hypertension (requiring at least two different drugs), diabetes, previous TIA/stroke, LA ? 50 mm, LVEF ? 40%, and ?70 years old. There is no evidence that dronedarone is more effective than amiodarone at maintaining sinus rhythm.