| 1 | Underlying heart disease | Structural heart disease (e.g. MI, cardiomyopathy) | Normal heart |
| 2 | Frequency | >10,000 VPCs/day or >10% burden | <1% burden, rare |
| 3 | Pattern | Bigeminy, couplets, triplets, runs | Isolated VPCs |
| 4 | Morphology | Polymorphic, multifocal | Monomorphic |
| 5 | VPC timing | R-on-T phenomenon | Occurs after T wave |
| 6 | Exercise stress test | VPCs in recovery phase | VPCs at peak exercise or absent |
| 7 | Symptoms | Syncope, presyncope, palpitations | Asymptomatic |
| 8 | Ejection fraction (EF) | LVEF <40% | LVEF >50% |
| 9 | Response to exercise | Increase in VPCs | Suppression with exercise |
| 10 | 24-hr Holter monitoring | >500 VPCs/hour | <30 VPCs/hour |
| 11 | Couplets/triplets | Present | Absent |
| 12 | Sustained VT history | Present | Absent |
| 13 | Family history of SCD | Present | Absent |
| 14 | VPC burden effect on LV | LV dysfunction (PVC-induced cardiomyopathy) | No effect on LV |
| 15 | Fusion beats | Seen (suggests re-entry) | Absent |
| 16 | QT interval | Prolonged QT with VPCs → torsades risk | Normal QT |
| 17 | Presence of scar (MRI) | Scar/fibrosis seen | Normal myocardium |
| 18 | Response to beta blockers | Poor/no response | Symptom relief |
| 19 | Inducibility on EP study | VT inducible | Not inducible |
| 20 | ICD indication | Meets primary/secondary prevention criteria | Not indicated |
