Palpitations and arrhythmia — likely diagnosis
For each clinical scenario below, select the SINGLE most likely diagnosis from the option list above. Each option may be used once, more than once, or not at all.
- A. Atrioventricular nodal re-entrant tachycardia (AVNRT)
- B. Atrial fibrillation
- C. Atrial flutter
- D. Ventricular tachycardia
- E. Wolff-Parkinson-White syndrome
- F. Torsades de pointes
- G. Sinus tachycardia
- H. Complete (third-degree) heart block
1. A 45-year-old man has a regular narrow-complex tachycardia at 150 beats per minute. The ECG shows a sawtooth baseline pattern of atrial activity, most visible in the inferior leads, at approximately 300 per minute with 2:1 AV conduction.
2. A 68-year-old woman with known ischaemic heart disease reports palpitations. Her pulse is irregularly irregular at 110 beats per minute, and no discrete P waves are visible on the ECG, with an irregular baseline.
3. A 60-year-old man develops a broad-complex regular tachycardia at 170 beats per minute three days after an anterior myocardial infarction. He is haemodynamically unstable.
4. A 22-year-old man has recurrent episodes of fast palpitations. His resting ECG between episodes shows a short PR interval and a slurred upstroke to the QRS complex (delta wave).
5. A 50-year-old woman started on a macrolide antibiotic while already taking an antipsychotic develops a polymorphic broad-complex tachycardia with a QRS axis that appears to twist around the isoelectric baseline. Her QTc prior to starting treatment was prolonged at 480ms.
6. An 82-year-old man presents with dizziness and syncope. His ECG shows a ventricular rate of 32 beats per minute with P waves marching through the rhythm at their own independent, faster rate, with no fixed relationship to the QRS complexes.