Hybrid Score to Predict OTVA-SOO in Patients with Wide Basal QRS

The Hybrid Score (HS), detailed in previous literature involves a sum of points based on clinical and ECG characteristics. Points are assigned as follows: one point each for being over 50 years old, male, and having arterial hypertension. ECG-based points are allocated according to QRS transition: 3 points for a transition in V1, 2 points for V2, 1 point for V3 if the R-wave in V3 is greater than 1 mV; 1 point is subtracted if V3 has an R-wave less than 1 mV, and further deductions or additions apply for transitions up to V6. A score ≤ 1 suggests an RVOT origin, whereas ≥ 2 suggests an LVOT origin.