Criteria for high cardiac risk in syncope
| Severe structural or coronary artery disease |
| Heart failure |
| Previous myocardial infarction |
| Left ventricular outflow tract obstruction |
| Clinical or electrocardiographic signs of arrhythmic syncope |
| Syncope during exertion or when supine |
| Palpitations at time of syncope |
| Family history of sudden cardiac death |
| Nonsustained ventricular tachycardia |
| Bifascicular block or intraventricular conduction |
| abnormality with QRS complex > 120 seconds |
| Inadequate sinus bradycardia or sinoatrial block |
| Pre-excited QRS |
| Prolonged or short QT interval |
| Right bundle branch block with Brugada pattern (ST-segment elevation in V1 –V3) |
| Negative T waves in precordial leads, epsilon wave, and ventricular late potentials suggestive of arrhyth mogenic right ventricular cardiomyopathy |