Table 2: Studies Investigating Electrocardiogram Criteria for Detection of Epicardial Ventricular Tachycardia Origin.
| Author and Year | Patients | Region Assessed | Methods | Criteria Assessed | Criteria Performance Endo versus Epi Pace Maps | Criteria Performance Endo versus Epi VT | Comments |
|---|---|---|---|---|---|---|---|
| Berruezo 200412 | CRT patients (pace map) and patients with VT of RBBB morphology | LV | Pace map endo/epi; VT endo/epi | PdV; IDT; SRS; QRSd | PdV, IDT; SRS and QRSd all significantly longer during epi compared to endo pace map | QRSd epi > QRSd endo PdW: SN 83 %; SP 95 % IDT: SN 87 %; SP 90 % SRS: SN 76 %; SP 85 % |
67 % of patients had ischemic cardiomyopathy |
| Bazan 200615 | Patients undergoing endo/epi pace mapping | RV | Pace map endo/epi | QRSd; QWL1; QSV2; QWIL; PdW; IDT; SRS | QRSd, PdW, IDT and SRS not different endo vs. epi pace map Anterior RV: QWL1: SN 52 %; SP 94 % QSV2: SN 67 %; SP 61 % Inferior RV: QWIL: SN 71 %; SP 74 % |
- | In RVOT and basal RV no criterion different endo vs. epi pace map; 39 % of patients had no structural heart disease |
| Daniels 200616 | Patients with idiopathic VT | LV (endo VT from RVOT as well) | VT endo/epi | QRSd; MDI | - | QRSd not different endo vs. epi VT MDI: SN 100%; SP 99 % (no prospective evaluation) |
All epi VT >1 cm away from aortic sinus of Valsalva and all perivascular |
| Bazan 200713 | Patients undergoing endo/epi catheter mapping and ablation | LV | Pace map endo/epi; VT epi | QRSd; PdV; IDT; SRS; QWL1; QSV2; QWIL | QRSd epi > QRSd endo PdV, IDT and SRS site specific PdW: SN 96 %; SP 29 % IDT: SN 39 %; SP 24 % SRS: SN 53 %; SP 79 % Basal superior LV: QWL1: 90 % epi and 16 % endo Apical superior LV: QWL1: 88 % epi and 26 % endo Basal inferior LV: QWIL: 81 % epi and 37 % endo Apical inferior LV: QWIL: 92 % epi and 33 % endo |
PdV, IDT and SRS above cut-off in 74 %, 47 % and 53 % of epi VT, respectively Basal superior LV VT: QWL1: 9/10 VT QWIL: 0/10 VT |
No patient had previous MI; 60 % of patients had NICM |
| Vallès 201014 | NICM and VT | Basal superior to lateral LV | Pace map endo/epi; VT endo/epi | QRSd; PdW; IDT; SRS; MDI; QWLI; NQWIL | QRSd epi > QRSd endo PdW: SN 73 %; SP 63 % IDT: SN 83 %; SP 70 % SRS: SN 74 %; SP 57 % MDI: SN 30 %; SP 89 % QWL1: SN 91 %; SP 96 % NQWIL: SN 99 %; SP 58 % |
QRSd epi > QRSd endo PdW: SN 62 %; SP 50 % IDT: SN 69 %; SP 50 % SRS : SN 93 % ; SP 50 % MDI: SN 33 %; SP 75 % QWL1: SN 88 %; SP 88 % NQWIL: SN 94 %; SP 63 % |
4-step ECG algorithm proposed for epi/endo VT origin: SN 93 % and SP 86% in a validation cohort |
NICM = Non-ischaemic cardiomyopathy MI = Myocardial infarction LV = Left ventricle RV = Right ventricle VT = Ventricular tachycardia Endo = Endocardial Epi = Epicardial SN = Sensitivity SP = Specificity QRSd = QRS duration PdW = Pseudo-delta wave IDT = Intrinsicoid deflection time SRS = Shortest RS complex MDI = Maximum deflection index QWL1 = Q wave in lead 1 QWIL = Q wave in inferior leads NQWIL = No Q wave in inferior leads QSV2 = QS complex in lead V2