We report the case of a 30-year-old man with situs inversus totalis, recurrent orthodromic reciprocal tachycardia, and the Wolff-Parkinson-White syndrome. He underwent, in our department, radiofrequency ablation of an accessory pathway (AP) located in the lateral mitral atrioventricular ring. Ablation of the AP was carried out successfully through a patent foramen ovale under fluoroscopic guidance, in a right anterior oblique projection with a 30° tilt and in anteroposterior views. We also used a mirror reversal of electrocardiogram (ECG) leads to better judge the site of the AP by using existing ECG algorithms. Complete situs inversus is a rare disorder, which has no consequence for the patient in the absence of cardiac or extracardiac involvement. Ablation of APs in situs inversus has been previously reported in only three cases of complete situs inversus and one case of situs ambiguous. In patients with mirror-image dextrocardia, APs seem more often located on the 'left' free wall (mitral annulus), as in the normal population. Radiofrequency ablation is feasible and safe after mirror reversion of the ECG electrodes and fluoroscopy.