Ventricular tachycardia (acute or history)
Structurally normal heart or scar? LVEF, scar pattern and cardiomyopathy type decide ablation and ICD.
Echo approach, step by step
The 2022 ESC guideline recommends echo in all patients with suspected or documented ventricular arrhythmias to assess LV function and structural heart disease. CMR is recommended when echo is inconclusive or a cardiomyopathy is suspected [38].
- LVEFThis is the main determinant of prognosis and ICD indication [38].
- ScarRegional thinning, akinesia, aneurysm (post-MI scar, sarcoid) [1,38].
- Cardiomyopathy typeHCM (thickness, apical aneurysm), ARVC (RV regional abnormalities), DCM, LV non-compaction [13,14,145].
- ValvesArrhythmic MVP with annular disjunction; AS [38].
- CongenitalRepaired tetralogy of Fallot (RV size, pulmonary regurgitation) [25].
- After the acute eventRegional wall motion for ischaemia [138].
- LVEF
- Scar / aneurysm
- Cardiomyopathy phenotype
- RV regional motion
- MVP / MAD
- Congenital
Causes & echo clues
| Substrate | Echo clue | Next |
|---|---|---|
| Post-MI scar | Regional akinesia, aneurysm, low EF | Ablation, ICD [38] |
| Dilated cardiomyopathy | Dilated LV, low EF | CMR, genetics, ICD [14,38] |
| HCM | Hypertrophy, apical aneurysm | SCD risk [13,181] |
| ARVC | RV regional dyskinesia, dilated RVOT | CMR, Task Force [145,146] |
| Sarcoidosis | Basal septal thinning, patchy dysfunction | PET, CMR [38] |
| Idiopathic (RVOT, fascicular) | Normal heart | Ablation; good prognosis [38] |
| Arrhythmic MVP | Bileaflet prolapse, MAD | CMR [38] |
Clinical pathway to the diagnosis
- AcuteABC; synchronised cardioversion if unstable; amiodarone or procainamide if stable [38,198].
- 12-lead ECG of the VTMorphology and axis localise the origin [38].
- BloodsElectrolytes, troponin, drug levels.
- Echo, then CMR[38].
- Coronary assessmentIn scar-related VT [38,139].
- ICD and ablation decisions[38].
Clinical pearls & pitfalls
Pitfall"SVT with aberrancy" in a patient with prior MI is VT until proved otherwise. Treat as VT [38].
- A normal echo does not exclude cardiomyopathy. CMR finds scar that echo misses (early ARVC, sarcoid, myocarditis) [38,146].
- History of VT → echo at follow-up to track LVEF and device indication [38].
Red flags
- Haemodynamically unstable VT → cardioversion first, echo later [38]
- VT storm (≥3 episodes in 24 hours) → ischaemia, electrolytes, drug toxicity [38]
- VT with LBBB morphology and inferior axis in a young patient → RVOT VT (benign) or ARVC [38,145]