Mock Cardiology Module 4

A 53-year-old man with a 20-year history of poorly controlled hypertension presents to the emergency department with atypical chest pain. His blood pressure is 172/98 mmHg.

His ECG shows tall R waves in lateral leads, deep S waves in V1-V2, and ST depression with asymmetric T wave inversion in the lateral leads (I, aVL, V5, V6). His high-sensitivity troponin I is 8 ng/L (reference: <26 ng/L) at 0 and 3 hours.

Which of the following best describes the ST-T wave changes seen on this ECG?

A 56-year-old painter presents with progressive dyspnoea over three months. He has no significant past medical history.

His ECG shows a QRS duration of 148 ms with a broad, notched R wave (RSR’ pattern) in V1 and a deep, wide S wave in V6.

His chest X-ray shows clear lung fields and a normal cardiac silhouette.

Which of the following additional ECG findings would be most consistent with the conduction abnormality described?

A 73-year-old man presents to the emergency department with 2 hours of crushing chest pain radiating to the jaw. His ECG shows ST elevation in leads II, III, and aVF with reciprocal ST depression in I and aVL.

His heart rate is 42 bpm and blood pressure is 78/50 mmHg. Jugular venous pressure is elevated at 10 cm above the sternal angle and his lungs are clear to auscultation.

Which of the following is the most appropriate next step to confirm the suspected additional territory of infarction?

An 88-year-old woman is brought to the emergency department after a syncopal episode resulting in a head laceration.

Her ECG shows a regular atrial rate of 80 bpm and a regular ventricular rate of 35 bpm. The PR intervals vary randomly with no consistent relationship between P waves and QRS complexes. The QRS complexes are wide at 140 ms.

Which of the following best explains the pathophysiology of this patient’s ECG findings?

A 53-year-old man with chronic kidney disease (eGFR 8 mL/min/1.73m²) is brought in by ambulance following an out-of-hospital cardiac arrest. He had missed his last two haemodialysis sessions.

His ECG shows a wide QRS complex (180 ms), absent P waves, and a sine wave pattern. His serum potassium is 8.9 mmol/L (reference: 3.5-5.2 mmol/L).

Which of the following is the most important initial intervention?

A 38-year-old woman with recently diagnosed thyrotoxicosis presents with palpitations and lightheadedness. Her heart rate is 148 bpm and blood pressure is 110/70 mmHg.

Her ECG shows an irregularly irregular rhythm with no discernible P waves, a narrow QRS complex, and varying R-R intervals.

Her TSH is < 0.01 mU/L (reference: 0.5-4.0 mU/L) and free T4 is 68 pmol/L (reference: 10-20 pmol/L).

Which of the following is the most appropriate initial agent for rate control in this patient?

A 53-year-old male smoker with a strong family history of premature coronary artery disease is admitted with crushing retrosternal chest pain.

His initial ECG shows ST elevation in leads V1-V4 with reciprocal ST depression in the inferior leads. He undergoes primary percutaneous coronary intervention with stenting to the left anterior descending artery.

On day 5, his ECG shows deep Q waves in V1-V4, isoelectric ST segments, and symmetric T wave inversions in the anterior leads.

What do the day 5 ECG changes most likely represent?

A 19-year-old male presents with palpitations and syncope. He is a regular cannabis user.

His GCS is 15 on presentation. His ECG shows a coved-type ST elevation > 2 mm in leads V1-V2 followed by T wave inversion, with a QRS morphology resembling incomplete RBBB.

Which of the following is the most important next step in his management?

A 29-year-old man presents to the emergency department with pre-syncope. He has had recurrent episodes of rapid palpitations since adolescence.

His resting ECG in sinus rhythm shows a short PR interval (100 ms; reference: 120-200 ms), a slurred upstroke of the QRS complex (delta wave), and a QRS duration of 130 ms.

He subsequently develops a broad-complex irregular tachycardia at a rate of 250 bpm with haemodynamic instability.

Which of the following drugs is most dangerous to administer in this situation?

A 52-year-old woman with metastatic breast cancer presents with progressive dyspnoea and hypotension (blood pressure 82/60 mmHg). Her JVP is elevated and heart sounds are muffled.

Her ECG shows sinus tachycardia with low voltage QRS complexes and alternating QRS amplitude (electrical alternans).

Which of the following is the most likely diagnosis?

A 74-year-old woman with a history of hypertension presents with near-syncope and severe dyspnoea. Her high-sensitivity troponin is 1814 ng/L (reference: <14 ng/L). The emergency department is concerned about STEMI.

Her ECG shows progressive prolongation of the PR interval over successive beats followed by a non-conducted P wave, with a regular grouped beating pattern. The QRS complexes are narrow.

Which of the following best describes the conduction abnormality and its most likely anatomical location?

A 53-year-old woman presents with acute chest pain following the recent diagnosis of thyroid cancer.

Her ECG shows diffuse ST elevation in the anterior and lateral leads.

Coronary angiography reveals no obstructive coronary artery disease. Left ventriculography shows apical ballooning with hyperkinesis of the basal segments.

Which of the following is the most likely diagnosis?

A 74-year-old woman presents with acute-onset dyspnoea and near-syncope.

Her heart rate is 120 bpm, blood pressure is 88/54 mmHg, and oxygen saturation is 86% on room air. Her high-sensitivity troponin is 1814 ng/L.

The emergency department is concerned about STEMI.

Her ECG shows sinus tachycardia, right axis deviation, S1Q3T3 pattern, T wave inversions in V1-V4, and incomplete RBBB.

Which of the following is the most appropriate next investigation?

A 22-year-old woman who is 22 weeks pregnant presents with palpitations. Her heart rate is 186 bpm and blood pressure is 105/65 mmHg. She is haemodynamically stable.

Her ECG shows a regular narrow-complex tachycardia with no discernible P waves and a rate of 186 bpm.

Which of the following is the most appropriate initial pharmacological intervention?

A 70-year-old man with a history of ischaemic cardiomyopathy (LVEF 25%) and an automated implantable cardioverter-defibrillator (AICD) presents to the emergency department after receiving multiple shocks from his device.

His ECG shows a wide-complex tachycardia at 180 bpm with a monomorphic morphology and AV dissociation.

Which of the following is the most appropriate acute pharmacological management in addition to device interrogation?

A 56-year-old man with no prior cardiac history presents to the emergency department with acute crushing chest pain of 90 minutes duration. His blood pressure is 100/68 mmHg and heart rate is 102 bpm.

His ECG shows a QRS duration of 160 ms, broad notched R waves in I, aVL, V5, and V6, absent Q waves in lateral leads, deep QS complexes in V1-V3, and 4 mm concordant ST elevation in leads V3 and V4.

His high-sensitivity troponin T is 450 ng/L (reference: <14 ng/L).

Which of the following ECG criteria is most useful in identifying acute myocardial infarction in this clinical context?

A 68-year-old man presents with 3 hours of inferior chest heaviness and diaphoresis.

His ECG confirms ST elevation in leads II, III, and aVF with reciprocal changes in I and aVL.

He is taken for primary percutaneous coronary intervention, which reveals a proximal right coronary artery occlusion.

Post-procedure, he develops recurrent episodes of sinus bradycardia at 38 bpm with intermittent sinus pauses of up to 3.5 seconds, causing presyncope.

Which of the following best explains the mechanism of this conduction disturbance?

A 62-year-old woman with type 2 diabetes presents with 2 hours of epigastric pain and nausea.

Her ECG shows ST depression in leads V1-V3 that is horizontal in morphology, tall R waves in V1 and V2 (R/S ratio > 1), and upright T waves in V1-V3. Leads II, III, and aVF show 1 mm ST elevation.

Her high-sensitivity troponin I is 2,340 ng/L (reference: <16 ng/L).

Which of the following additional ECG leads would be most useful to confirm the suspected additional territory of infarction?

A 70-year-old man with a history of ischaemic cardiomyopathy (LVEF 30%) presents with haemodynamically stable wide-complex tachycardia at 160 bpm.

His ECG shows a QRS duration of 170 ms, northwest axis, AV dissociation with visible P waves marching through the rhythm at a rate of 72 bpm, and capture and fusion beats.

Which of the following features on this ECG is most specific for ventricular tachycardia rather than supraventricular tachycardia with aberrant conduction?

An 87-year-old man presents with dizziness, lethargy, fevers, and dysuria. His CRP is 240 mg/L (reference: <5 mg/L) and high-sensitivity troponin I is 42 ng/L (reference: <26 ng/L). Blood cultures grow Escherichia coli.

His ECG shows a ventricular rate of 38 bpm, a QRS duration of 130 ms, and complete AV dissociation with a wide-complex escape rhythm.

His baseline ECG from 6 months ago showed normal sinus rhythm with a narrow QRS and a PR interval of 210 ms.

Which of the following is the most likely primary mechanism of this patient’s conduction disturbance?

A 72-year-old man with a history of ischaemic cardiomyopathy (LVEF 35%) and prior inferior myocardial infarction presents with two episodes of sudden loss of consciousness over the past month.

Both episodes occurred while seated, lasted less than one minute, and were followed by rapid complete recovery without confusion or tongue biting. There was no prodrome.

His resting ECG shows sinus rhythm at 62 bpm, pathological Q waves in II, III, and aVF, left anterior fascicular block, and a QRS duration of 125 ms.

A 48-hour Holter monitor shows occasional ventricular ectopy but no sustained arrhythmia. Echocardiography confirms inferior wall akinesis with LVEF 35%.

Which of the following investigations is most likely to establish a diagnosis in this patient?

A 82-year-old woman (weight 58 kg) with permanent atrial fibrillation and a CHA2DS2-VASc score of 5 is reviewed in clinic.

Her current medications include apixaban 5 mg twice daily, bisoprolol 5 mg daily, and perindopril 5 mg daily.

Her serum creatinine is 140 micromol/L (reference: 45-90 micromol/L), eGFR is 34 mL/min/1.73m², haemoglobin is 118 g/L (reference: 115-160 g/L), and platelets are 210 x 10^9/L (reference: 150-400 x 10^9/L).

Which of the following is the most appropriate change to her anticoagulation?

A 32-year-old woman presents to the emergency department with sudden-onset regular palpitations and a sensation of pounding in her neck.

She is haemodynamically stable with a heart rate of 180 bpm and blood pressure of 108/72 mmHg.

Her ECG shows a regular narrow-complex tachycardia at 180 bpm.

Close inspection reveals pseudo R-prime deflections in V1 and pseudo S waves in the inferior leads that are absent on her baseline ECG in sinus rhythm. No clearly discernible P waves are seen separate from the QRS complex.

Which of the following is the most likely diagnosis?

A 56-year-old man with paroxysmal atrial fibrillation, hypertension, obstructive sleep apnoea (untreated), and a BMI of 38 kg/m² is reviewed following a second AF ablation procedure 6 months ago.

He continues to have symptomatic AF recurrences despite the procedure.

His current medications include rivaroxaban 20 mg daily, candesartan 16 mg daily, and amlodipine 5 mg daily.

His blood pressure is 148/92 mmHg. He drinks 14 standard alcoholic drinks per week and does not exercise.

Which of the following interventions has the strongest evidence for reducing his AF burden?

A 64-year-old woman with non-ischaemic dilated cardiomyopathy has been on maximally tolerated guideline-directed medical therapy (sacubitril-valsartan, carvedilol, dapagliflozin, spironolactone) for 8 months. She remains symptomatic with NYHA class III dyspnoea.

Her LVEF is 28% on echocardiography, and her resting ECG shows sinus rhythm with a left bundle branch block morphology and QRS duration of 162 ms.

Which of the following device therapies is most appropriate for this patient?

A 72-year-old man presents to the emergency department with palpitations and light-headedness. He has a history of anterior ST-elevation myocardial infarction 3 years ago, managed with percutaneous coronary intervention to the left anterior descending artery.

His current medications include aspirin, atorvastatin, ramipril, and bisoprolol.

His last echocardiogram showed a left ventricular ejection fraction (LVEF) of 30% with an apical aneurysm. His blood pressure is 95/60 mmHg.

A 12-lead ECG shows a regular wide complex tachycardia at 160 bpm with a right bundle branch block morphology, left axis deviation, and positive concordance across the precordial leads with AV dissociation evident.

Which of the following is the most appropriate immediate management?

A 38-year-old woman is referred to the cardiology clinic with a 6-month history of palpitations and exercise intolerance. She has no significant past medical history and takes no regular medications.

A 24-hour Holter monitor reveals a premature ventricular complex (PVC) burden of 32%, predominantly with a left bundle branch block morphology and inferior axis.

An echocardiogram demonstrates a left ventricular ejection fraction (LVEF) of 38% with global hypokinesis.

Cardiac MRI shows no late gadolinium enhancement, no fatty infiltration, and no regional wall motion abnormalities to suggest arrhythmogenic right ventricular cardiomyopathy.

Coronary angiography is normal.

What is the most appropriate next step in management?

A 22-year-old man presents to the emergency department after a syncopal episode at a nightclub. He is alert but anxious. His heart rate is 250 bpm and blood pressure is 100/70 mmHg.

A rhythm strip shows an irregularly irregular wide complex tachycardia with varying QRS morphology and duration. Some QRS complexes are relatively narrow while others are markedly broad. The shortest pre-excited R-R interval is 210 ms.

Which of the following medications is most dangerous to administer in this clinical scenario?

A 55-year-old man with ischaemic cardiomyopathy (LVEF 25%) and an implantable cardioverter-defibrillator (ICD) presents with three appropriate ICD shocks in the past month for monomorphic ventricular tachycardia.

His ICD has been appropriately programmed with anti-tachycardia pacing and optimised detection settings.

He is currently taking bisoprolol 10 mg daily and amiodarone 200 mg daily. His electrolytes are normal and there is no evidence of acute ischaemia.

According to current guidelines, what is the most appropriate next step in management?

A 44-year-old woman with a history of paroxysmal atrial fibrillation is brought to the emergency department by ambulance after developing palpitations, dizziness, and near-syncope. She takes flecainide 100 mg twice daily and bisoprolol 2.5 mg daily.

Her ECG shows a regular wide complex tachycardia at 250 bpm with a monomorphic QRS morphology. The QRS duration is 190 ms with a right bundle branch block pattern.

Which of the following best explains the mechanism of this arrhythmia?