{
  "abstract": "Background Left atrial ablation may result in left atrial peri-mitral flutter. Ablating a mitral isthmus (MI) line is an established treatment, which creates a line of block between the annulus from a septal or lateral position to a pulmonary vein (PV) however this line poses several challenges. The line courses proximal to the left circumflex artery, the tricuspid valve leaflets and the posterior left atrial wall which may all result in complications. If the line is not complete however, it conversely increases the risk of flutter. Robust bidirectional block in many cases requires ablation from the coronary sinus (CS), or rarely, ethanol injection in the vein of marshall (VOM).Methods We retrospectively analysed patients who underwent PV isolation and MI ablation in our centre with a dual energy catheter. Patient and procedure data were collected and analysed. Data on clinical intervention such as cardioversion and ECG at 3 months were collected.Results 47 patients were identified who had 3 month follow up, see table 1 for results. 38 (80.8%) patients had either persistent or longstanding persistent AF. Patients generally had radiofrequency energy applied from the annulus, with pulsed-field energy along the line as the myocardium thickens towards the posterior wall, see Abstract 26 Figure 1. All patients (100%) achieved acute bidirectional block, with 8 patients requiring ablation with ablation within the CS. 44 patients had a lateral MI line. There was no coronary spasm or other major complications. 36 patients (73.5%) maintained sinus rhythm at 3 months.Conclusion Creation of MI lines with this catheter was fast, requiring a median of 8 minutes additional procedure time and no major complications. Good success was achieved, acutely with bidirectional line block (100%) and freedom from atrial arrhythmia at 3 months (76.6%). CS ablation was only required in 2 patients with no VOM intervention.Abstract 26 Table 1Baseline patient characteristics, procedural data and follow upAbstract 26 Figure 1Mapping system and dual-energy catheter. Green discs represent pulsed field lesions, red discs radiofrequency ablation lesions",
  "authors": [
    {
      "affiliations": [
        "Beacon Hospital, Dublin, Ireland",
        "Cork University Hospital, Cork, Ireland"
      ],
      "name": "J Mannion"
    },
    {
      "affiliations": [
        "Beacon Hospital, Dublin, Ireland"
      ],
      "name": "A Stone"
    },
    {
      "affiliations": [
        "Beacon Hospital, Dublin, Ireland"
      ],
      "name": "D Crinion"
    },
    {
      "affiliations": [
        "Beacon Hospital, Dublin, Ireland"
      ],
      "name": "S Tuohy"
    },
    {
      "affiliations": [
        "Beacon Hospital, Dublin, Ireland",
        "School of Medicine, University College Dublin, Dublin, Ireland"
      ],
      "name": "J Lyne"
    }
  ],
  "title": "26 Dual-energy pulsed field and radiofrequency mitral isthmus line ablation outcomes using a lattice-tipped catheter",
  "uid": "1ff6dd6c-e026-5479-80ba-dd0b88ff8c25"
}