Alternative techniques for left ventricular pacing in cardiac resynchronization therapy.

Cardiac resynchronization therapy (CRT) is an important treatment modality for a well-defined subgroup of heart failure patients. Coronary sinus (CS) lead placement is the first-line clinical approach but the insertion is unsuccessful in about 5-10% of the patients. In recent years, the number of CRT recipients and the considerable need for left ventricular (LV) lead revisions increased enormously. Numerous techniques and technologies have been specifically developed to provide alternatives for the CS LV pacing. Currently, the surgical access is most frequently used as a second choice by either minithoracotomy or especially the video-assisted thoracoscopy. The transseptal or transapical endocardial LV lead implantations are being developed but there are no longer follow-up data in larger patient cohorts. These new techniques should be reserved for patients failing conventional or surgical CRT implants. In the future, randomized studies are needed to asses the potential benefits of some alternative LV pacing techniques and other new technologies for LV lead placement are expected.