Early scar evaluation by LGE-CMR at 3 to 6 months post-VT ablation is strongly associated with long-term VT recurrence and reveals sustained reduction in scar heterogeneity.
Observational
Does postablation LGE-CMR assessment of scar characteristics predict long-term VT recurrence?
Postablation LGE-CMR at 3 to 6 months provides durable assessment of scar characteristics that strongly predict long-term VT recurrence and demonstrate favorable reverse remodeling.
BACKGROUND: Late gadolinium enhancement cardiac magnetic resonance (LGE-CMR) is useful for identifying ventricular tachycardia (VT) substrate in patients with structural heart disease. While preprocedural LGE-CMR is widely used for planning, the role of postprocedural LGE-CMR in evaluating VT ablation success and long-term scar evolution has been less explored. This study aimed to prospectively and systematically assess the long-term evolution of scar and ablation lesions using serial postablation LGE-CMR with long-term follow-up. METHODS: This prospective study included 51 patients (mean age, 65.2±9.8 years; men, 95.8%; ischemic heart disease, 83%; left ventricular ejection fraction, 34.5±10.4%) undergoing their first substrate-based VT ablation between March 2019 and July 2020. Preprocedural LGE-CMR and 2 postprocedural scans at 3 to 6 months (CMR-1) and 18 to 24 months (CMR-2) were performed. Scar characteristics, including core scar, border zone, and conducting channels, were analyzed. VT recurrence was monitored, and factors associated with recurrence were evaluated using a Cox proportional hazards model. A Kaplan-Meier curve was used to represent the VT-free survival function. RESULTS: Core scar mass increased significantly from baseline to CMR-1 (12.2±1.5 to 19.8±1.6 g, P<0.01) and remained stable at CMR-2. In contrast, the border zone decreased significantly over time (pre, 25.3±1.8 g; CMR-1, 20.8±2.0 g; CMR-2, 16.7±2.1 g; P<0.01). A significant decrease in conducting channels was noted after ablation and persisted at CMR-2 (pre, mean 2.4±0.2/median 2 interquartile range, 1-3; CMR-1, mean 1.4±0.2/median 1 interquartile range, 0-1; CMR-2, mean 1.6±1.0/median 1 interquartile range, 0-1; P<0.001). VT recurrence occurred in 29.4% of patients during a median follow-up of 3.1 years. The number of conducting channels at CMR-1 and their relative reduction from baseline were related to VT recurrence. The persistence of 2 or more conducting channels at CMR-1 was associated with a higher recurrence rate: 75.6 versus 19.5% (hazard ratio HR; 4.1; 95% CI, 2.4-12.1; P=0.012). Evidence of favorable left ventricular remodeling was observed, with a significant reduction in left ventricular volume at CMR-2 (131.8±8.6 mL; CMR-1, 156.7±8.1 mL and 160.8±7.6 mL at baseline <0.01). CONCLUSIONS: Postablation LGE-CMR reveals durable changes in scar characteristics, with early scar evaluation at 3 to 6 months strongly associated with long-term VT recurrence. The reduction in scar heterogeneity and conducting channels is sustained over time, underscoring the usefulness of LGE-CMR for assessing ablation success. Additionally, VT ablation appeared to be associated with favorable reverse remodeling, highlighting potential benefits beyond arrhythmia control. These findings support the use of LGE-CMR for personalized management following VT ablation.
“I think this is a really hard problem. VT ablation obviously has devastating consequences. Even if you put ICDs in, patients don't like getting shocks. So what we can do to make these treatments more tolerable to patients and more effective is really critical. The other thing is these are really remarkable results. 75% of patients that have a successful VT ablation, meaning less than one or less conducting channels left behind, don't have recurrent VT over this kind of follow-up time period. That's a huge result that patients really will like to hear, but it's still a hard problem that the remaining 20% or so still have recurrent VT, and we have to figure out how to take care of that problem. And the idea of imaging before and after the ablation is a way to get a structural or an imaging result to say, 'What's the likelihood of success of this ablation procedure?' So I think we can learn from the before and after imaging how to make VT ablation a much more effective procedure, and hopefully that will lead to long-term better outcomes.”
Roca et al. (2026) conducted an observational in Ventricular Tachycardia. Late Gadolinium Enhancement Cardiac Magnetic Resonance (LGE-CMR) was evaluated on Long-term VT recurrence and scar characteristics. Early scar evaluation by LGE-CMR at 3 to 6 months post-VT ablation is strongly associated with long-term VT recurrence and reveals sustained reduction in scar heterogeneity.