Antecedent symptoms, family history and relevant cardiac history of the 118 subjects*
| Patient information | No of cases | Age (years) | |
| ⩽35 | >35 | ||
| Family history | 20 (17%) | 15 | 5 |
| Family history of heart disease | 13 | 9 | 4 |
| Family history of SCD | 8 | 6 | 2 |
| Symptoms | 21 (18%) | 16 | 5 |
| Syncope/dizziness | 10 | 9 | 1 |
| Shortness of breath | 7 | 5 | 2 |
| Palpitations | 6 | 6 | 0 |
| Chest pain | 4 | 3 | 1 |
| Relevant past medical history | 25 (21%) | 16 | 9 |
| Clinical suspicion of cardiac disease after investigation† | 9 | 6 | 3 |
| Epilepsy/seizure | 4 | 4 | 0 |
| Heart murmur | 3 | 3 | 0 |
| Diabetes | 3 | 1 | 2 |
| Hypercholesterolaemia | 4 | 0 | 4 |
| Congenital heart disease | 1 | 1 | 0 |
| Ventricular septal defect | 2 | 2 | 0 |
| Previous cardiac arrest | 2 | 1 | 1 |
| Atrial fibrillation/pacemaker insertion | 1 | 0 | 1 |
| Viral myocarditis | 1 | 1 | 0 |
*Symptoms/findings do not add up since some subjects had more than one symptom/finding; †abnormal ECG (n = 4), abnormal echo (n = 2), possible arrhythmia (n = 3).
SCD, sudden cardiac death.