Long-term outcomes in a randomized controlled trial of multimodality imaging-guided left ventricular lead placement
Daniel Benjamin Fyenbo1,2, Anders Sommer3, Bjarne Linde Nørgaard1
1Department of Cardiology, Aarhus University Hospital, Palle Juul-Jensens Boulevard 99, 8200 Aarhus N, Denmark.
Insights
Individualized imaging-guided cardiac resynchronization therapy (CRT) lead placement did not reduce heart failure hospitalizations or death. However, inter-lead electrical delay (IED) greater than 100ms was associated with improved outcomes in CRT patients.
Area of Science:
- Cardiology
- Medical Imaging
- Electrophysiology
Background:
- Cardiac resynchronization therapy (CRT) aims to improve heart failure outcomes by synchronizing ventricular contractions.
- Optimizing left ventricular (LV) lead placement is crucial for CRT efficacy.
- Current methods for LV lead placement vary, with potential for improvement through advanced imaging.
Purpose of the Study:
- To compare long-term outcomes of imaging-guided CRT LV lead placement versus routine fluoroscopic placement.
- To assess the association between inter-lead electrical delay (IED) and CRT response.
Main Methods:
- A randomized trial (ImagingCRT) comparing multimodality imaging-guided LV lead placement with fluoroscopic guidance.
- Long-term follow-up for the composite endpoint of heart failure hospitalization or all-cause death.
- Analysis of IED in relation to primary endpoint occurrence.
Main Results:
- No significant difference in the primary endpoint (HF hospitalization or all-cause death) between imaging-guided and routine CRT groups (HR 1.22, P=0.31).
- Individualized imaging guidance did not reduce HF hospitalization (HR 1.11, P=0.72) or all-cause death (HR 1.23, P=0.32) risks.
- A significantly reduced risk of the primary endpoint was observed in patients with IED ≥100 ms compared to those with IED <100 ms (HR 0.62, P=0.04).
Conclusions:
- Individualized multimodality imaging-guided LV lead placement did not improve long-term heart failure or mortality outcomes compared to routine placement.
- Inter-lead electrical delay (IED) may serve as a potential predictor of CRT response.
- Further research into targeting latest electrical activation is warranted for optimizing LV lead placement in CRT.
Aims:
This study aims to investigate the long-term occurrence of the composite endpoint of heart failure (HF) hospitalization or all-cause death (primary endpoint) in patients randomized to cardiac resynchronization therapy (CRT) using individualized multimodality imaging-guided left ventricular (LV) lead placement compared with a routine fluoroscopic approach. Furthermore, this study aims to evaluate whether inter-lead electrical delay (IED) is associated with improved response rate of this endpoint.
Methods And Results:
We reviewed follow-up data until November 2020 for all 182 patients included in the ImagingCRT trial for the occurrence of HF hospitalization and all-cause death. During median (inter-quartile range) time to primary endpoint/censuring of 6.7 (3.3-7.9) years, the rate of the primary endpoint was 60% (n = 53) in the imaging group compared with 52% (n = 48) in the control group [hazard ratio (HR) 1.22, 95% confidence interval (CI) 0.83-1.81, P = 0.31]. Neither the risk of HF hospitalization (HR 1.11, 95% CI 0.62-1.99, P = 0.72) nor of all-cause death differed between treatment groups (HR 1.23, 95% CI 0.82-1.85, P = 0.32). The risk of the primary endpoint was significantly reduced among those with IED ≥100 ms when compared with those with IED <100 ms (HR 0.62, 95% CI 0.39-0.98, P = 0.04).
Conclusions:
In this study, an individualized multimodality imaging-guided strategy targeting LV lead placement towards the latest mechanically activated non-scarred myocardial segment during CRT implantation did not reduce HF hospitalization or all-cause death when compared with routine LV lead placement during long-term follow-up. Targeting the latest electrical activation should be studied as an alternative individualized strategy for optimizing LV lead placement in CRT recipients.
