**3.1 Lead placement sites**

Current approaches to the CSP base on the placement of the permanent pacing leads in the sites of the cardiac conduction system other than the RVA. CSP intends to overcome an asynchronous activation during pacing by producing the most physiologic activation pattern close to the one seen in the intrinsic conduction system. For that purpose, CSP leads may be implanted either at the HB or at the region of the left bundle branch (LBB) for different resynchronization strategies (**Figure 1**). The advantages and limitations of different strategies will be discussed later in the chapter.
