Key Points:
- Among patients who undergo endocardial ablation for left ventricular arrythmias, it is uncertain whether the number of imaging-detected cerebral emboli differs based on the anatomical approach.
- In this randomized trial, participants who were assigned to a transseptal approach had significantly lower rates of imaging-detected cerebral emboli compared to those assigned to a retrograde aortic approach.
Rates of left ventricular (LV) catheter ablation (CA) to address frequent premature ventricular contractions (PVC) or ventricular tachycardia (VT) have increased significantly over the past 5 years. Up to 64% of patients who undergo LV ablation procedure are subsequently found to have an imaging-detected brain embolism on diffuse-weighted MRI. Whether rates differ based on anatomical approach (retrograde aortic or transseptal) is uncertain.
On April 8, 2024, the principal results of “TRAVERSE: Transseptal versus Retrograde Aortic Ventricular Entry to Reduce Systemic Emboli” were presented at ACC Scientific Sessions 2024. The purpose of this study was to determine whether the incidence of imaging-detected cerebral embolism was lower with a transseptal compared to a retrograde aortic approach to LV CA.
This trial randomized patients planned for LV endocardial VT or PVC ablation to a transseptal or retrograde aortic approach in a 1:1 fashion in blocks by study site. Patients were excluded if they had contraindication to MRI or to either approach (such as mechanical valve or severe stenosis in the aortic or mitral position, the presence of a closure device in the septum, or a prior mitral clip or Alfieri repair). All patients had baseline brain MRI and neurocognitive testing. A repeat brain MRI was performed on post-procedure day 1 and repeat neurocognitive testing at 6 months.
Overall, 146 patients were randomized and underwent LV CA, 72 via retrograde aortic approach and 74 vis transseptal approach with follow up completion rates of 71% and 87%, respectively. Mean age was 64 years, ~20% were female, and ~85% were White; 3% in the retrograde aortic group had a history of stroke compared to 7% in the transseptal group. Of the retrograde aortic group, 4% ultimately underwent transseptal approach only and 10% underwent transseptal puncture after starting retrograde. Of the transseptal group, 5% ultimately underwent retrograde aortic access only and 4% underwent retrograde after starting with transseptal puncture. Median ablation and procedure time as well as procedural success rates were similar in the two groups.
In an intention to treat analysis, those randomized to transseptal approach had significantly lower rates of acute cerebral emboli on post-procedure MRI (28% vs. 45%, p =0.036). This effect was more pronounced in the as-treated analysis (23% in the only transseptal group vs. 49% in any retrograde aortic group, p = 0.0016). There was no significant difference between the groups in the cognitive composite scores at baseline or at 6 months. Limitations in this study include small sample size, loss to follow up, cross-over between the two groups, and protocol modifications related to COVID-19 interruptions.
Dr. Gregory Marcus, MD, MAS of University of California, San Francisco, concluded: “A transseptal approach to endocardial left ventricular catheter ablation results in significantly less frequent acute brain emboli compared to a retrograde aortic approach. The transseptal approach may mitigate against neurocognitive decline after these procedures, although missing data at 6 months precludes confident conclusions.”