The following are key points to remember from a state-of-the-art review on imaging to facilitate ventricular tachycardia (VT) ablation:

1. Ventricular arrhythmias are the primary cause of sudden cardiac death (SCD), and even when SCD is aborted, lead to significant morbidity and mortality. Catheter ablation is a well-established and effective strategy for the management of VT.
2. However, the identification and characterization of arrhythmogenic substrates for targeted ablation remain challenging.
3. Electrogram abnormalities and responses to pacing during VT provide the classical and most validated methods to identify substrates. However, the three-dimensional nature of the myocardium, nonconductive tissue, and heterogeneous strands of conductive tissue at the border zones or through the nonconductive zones can prohibit easy electrical sampling and identification of the tissue critical to VT.
4. Intracardiac echocardiography is critical for identification of anatomy, examination of catheter approach and contact, assessment of tissue changes during ablation, and even potential substrates as echogenic regions, but lacks specificity with regard to the latter compared with advanced modalities.
5. Recently, cardiac magnetic resonance (CMR), computed tomography (CT), and positron emission tomography (PET) have emerged as valuable tools in the periprocedural evaluation of VT ablation.
6. CMR has unparalleled soft tissue and temporal resolution and excels at identification of expanded interstitial space caused by myocardial infarction, fibrosis, inflammation, or infiltrative myopathies.
7. CT has excellent spatial resolution and is optimal for identification of anatomic variabilities including wall thickness, thrombus, and lipomatous metaplasia.
8. PET excels at identification of substrates including amyloidosis, sarcoidosis, and other inflammatory substrates.
9. These imaging modalities are vital for assessing arrhythmogenic substrates, guiding optimal access strategy, and assessing ablation efficacy. Although clearly beneficial in specific settings, further clinical trials are needed to enhance generalizability and optimize integration of cardiac imaging for VT ablation.
10. Ongoing research should also focus on evaluating the long-term efficacy and lasting impact of ablation procedures guided by the extraction of image features. Long-term follow-up studies are of paramount importance to assess the durability of VT suppression and the impact on patient outcomes.

Clinical Topics: Arrhythmias and Clinical EP, Noninvasive Imaging, SCD/Ventricular Arrhythmias, Cardiovascular Care Team

Keywords: Ablation, Diagnostic Imaging, Tachycardia, Ventricular

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