Figure 1.

ECG/VCG before radiofrequency catheter ablation (RFCA). ECG: Short PR interval, QRS axis −75°, QRS duration 160 ms, δ waves, QS in II, III and aVF, RBBB pattern. VCG: The QRS loop leaves no doubt about the presence of LAFB in the frontal and horizontal planes (FP/HP) a typical RBBB VCG pattern with final conduction delay in the right anterior quadrant. Initial conduction delay in the three planes. Conclusion: ventricular preexcitation with posteroseptal accessory pathway (AP), atypical LAFB and RBBB