Introduction
Transvenous right ventricular (RV) endocardial lead placement is the conventional practice in clinical pacing. In some situations, as in the presence of prosthetic tricuspid valve (PTV), the inaccessibility to the RV makes the permanent pacing through a coronary sinus (CS) lead placement a good alternative. [1-2] There are also described cases of dual-site ventricular pacing through the coronary sinus to cardiac resynchronization in patients with high pacemaker dependance and lower left ventricle (LV) ejection fraction.[3-5]
Epicardial lead implantation may be an alternative but requires invasive surgical placement, making it a less ideal option in patients with a prior thoracotomy. Regarding single ventricle pacing with a CS lead, low sensing and unacceptable threshold at implantation can be an important issue, especially when using a conventional RV pacing lead.[1-2] Quadripolar LV leads are associated with more satisfactory results as they are able to pace in several places of the LV wall, multiple vectors along the lead, allowing us to avoid suboptimal pacing sites, such as places with fibrosis.[6]