LAUSR

The number of heart failure patients who benefit from cardiac resynchronization therapy (CRT) devices, continues to increase around the world. Endovascular delivery of a lead into the coronary sinus (CS) is the most common approach to achieve left ventricular (LV) stimulation; however, it has a failure rate of 2.9%, mostly owing to coronary venous anatomy restrictions.1 Moreover, there is a significant portion of patients who are not responders despite CS stimulation, and in whom CS cannulation is not possible after a previous lead extraction.2 Normally, the next step to provide resynchronization in such cases is through a surgical procedure for epicardial LV implantation. However, such approach is associated with higher morbidity, difficulty to access optimal pacing sites, higher risk of lead dysfunction, and greater electromechanical delay.3, 4 As such, novel techniques have emerged to provide LV endocardial stimulation, including implantation through an interatrial septum puncture, an interventricular septum approach,5, 6 and, most recently, wireless stimulation.7 Recent studies have shown the superiority of endocardial stimulation in comparison to traditional CS pacing. In this clinical case, we will describe the implantation of an LV endocardial lead, using both fluoroscopy and intracardiac echocardiography (ICE) using a right subclavian vein puncture.