Syncope — Written Clinical Reasoning

SAQ — Syncope in an Older Man with Comorbidities (20 marks, 30 minutes)

Prompt: Outline your integrated assessment and management plan for this patient, including the ESC 2018 classification of his syncope, the role of each investigation, the risk stratification, and the evidence-based management strategy. Justify each decision with reference to guidelines and key trials. ^[1]

Model Answer

Problem list and provisional diagnosis (3 marks): ^[1]

1. Recurrent syncope — three episodes in 3 months, all in the morning on standing, with a prodrome of light-headedness
2. Orthostatic hypotension — documented: systolic drop of 38 mmHg on standing (146 to 108), exceeding the 20 mmHg threshold for classical OH, with a heart rate rise of only 4 bpm suggesting impaired baroreflex
3. Medication-induced vasodilation — amlodipine (calcium channel blocker) and doxazosin (alpha-blocker) both contribute to OH
4. Structural heart disease — previous MI with LVEF 40 per cent and anterior wall motion abnormality
5. Bifascicular block on ECG — RBBB plus left anterior fascicular block, a high-risk finding
6. Type 2 diabetes — risk of autonomic neuropathy contributing to OH
7. Benign prostatic hyperplasia — reason for doxazosin, a common and potent medication precipitant of OH ^[1]

The provisional diagnosis is multifactorial syncope: orthostatic hypotension from medication-induced vasodilation and possible diabetic autonomic neuropathy is the most likely mechanism, given the morning occurrence, the prodrome, and the documented orthostatic drop. However, the bifascicular block and reduced LVEF mean that an arrhythmic cause (intermittent high-grade AV block or VT) must be excluded. This patient has both a likely explanation (OH) and a high-risk alternative (arrhythmia) that coexist. ^[1]