Cardiac Arrhythmias and Conduction Disorders — WACS Viva & Clinical Scenarios (Cardiovascular Medicine)

Exam-style cardiac arrhythmias and conduction disorders viva scenarios with examiner probes and model answers for Internal Medicine candidates.

Scenarios covered

• SCENARIO 1: A 62-year-old male with a history of prior anterior wall myocardial infarction presents to the emergency department with sudden-onset palpitations, lightheadedness, and diaphoresis. His blood pressure is 85/55 mmHg, heart rate is 175 beats per minute, respiratory rate is 24 breaths per minute, and oxygen saturation is 94% on room air. The 12-lead ECG reveals a regular monomorphic wide-complex tachycardia with a QRS duration of 160 ms. Outline your immediate emergency approach, diagnostic algorithm to differentiate ventricular tachycardia from supraventricular tachycardia with aberrancy, and on
• SCENARIO 2: A 68-year-old female known to have chronic hypertension presents for routine follow-up. Physical examination reveals an irregularly irregular pulse at a rate of 118 beats per minute. A 12-lead ECG confirms new-onset atrial fibrillation with rapid ventricular response. Detail your structured clinical evaluation, including stroke and bleeding risk stratification, the rationale and choice between rate versus rhythm control strategies, and the selection of systemic anticoagulation.
• SCENARIO 3: A 74-year-old male is brought to the resuscitation room following a sudden syncopal episode while gardening. On examination, he is pale and clammy with a heart rate of 32 beats per minute and blood pressure of 80/45 mmHg. The 12-lead ECG demonstrates regular P waves at 80 beats per minute and independent regular wide QRS complexes at 32 beats per minute with no fixed PR relationship. Detail your immediate resuscitation sequence, medical stabilization, identification of reversible triggers, and definitive management pathway.
• SCENARIO 4: A 28-year-old male presents with sudden-onset rapid palpitations and dizziness. An ECG reveals an irregular, wide-complex tachycardia with variable QRS morphology and ventricular rates fluctuating between 180 and 260 beats per minute. A previous resting ECG is reviewed and shows a short PR interval and a delta wave. Formulate your acute emergency management plan, highlighting critical pharmacological contraindications and definitive electrophysiological interventions.
• SCENARIO 5: A 54-year-old female receiving psychiatric medication and antimicrobial therapy for pneumonia develops recurrent polymorphic ventricular tachycardia following a syncopal episode. Her baseline corrected QT interval (QTc) is measured at 560 ms. Discuss the electrophysiological mechanisms underlying this arrhythmia, emergency pharmacological and non-pharmacological termination protocols, and long-term risk reduction strategies.