Left Ventricular Endocardial Pacing Therapy Guided by 3D Mapping for Conventional Cardiac Resynchronization Therapy Non-Response or Face Challenges.

Aims: This study aims to evaluate the feasibility, efficacy, procedural complications, and long-term outcomes of left ventricular (LV) endocardial pacing lead implantation at the latest activation site of the LV. This procedure is guided by three-dimensional (3D) mapping and performed via transseptal puncture, and targets heart failure (HF) patients who either do not respond to conventional cardiac resynchronization therapy (CRT) or face challenges in lead implantation.

Methods and results: A retrospective analysis of clinical data was performed on 11 patients with dilated cardiomyopathy who were treated with LV endocardial pacing. Compared to conventional CRT, this procedure required longer operation and fluoroscopy times and higher radiation dose. Clinical improvements, as evidenced by at least one New York Heart Association class improvement, were achieved in 63.6% of the patients, with an average decrease in Minnesota Living with Heart Failure Questionnaire score of 33.8 ± 2.2 points (p < 0.05). However, complications and adverse events were noted in 3 patients (27.3%) one month postoperatively, including pocket hematomas in 3 patients (27.3%), a pocket infection in 1 patient (9.1%), and a thromboembolic event in 1 patient (9.1%). In addition, 3 patients (27.3%) had worsening HF after implantation. The estimated mortality rates at 1, 3, and 5 years post-implantation were 9.1%, 18.2%, and 27.3%, respectively.

Conclusions: Implanting the LV endocardial pacing lead at the latest activation site under 3D mapping guidance via transseptal puncture offers a viable alternative for patients eligible for CRT who face challenges with LV epicardial lead implantation due to anatomical issues or CRT non-response. However, this procedure is associated with a relatively high incidence of complications, requires careful patient selection, and may necessitate lifelong anticoagulation after implantation.