{
  "abstract": "Introduction Cardiac resynchronization therapy (CRT), to date, remains a pertinent treatment modality to correct cardiac dyssynchrony (CD) and restore left ventricular systolic function (LVSF) amongst indicated patients. CRT remains underutilised and implantation is affected by significant delays across Europe.Methods This retrospective review screened patients admitted to the Heart Failure Unit of St. Michael’s Hospital over a 4-year period for eligibility of CRT, using indications of CRT delineated by the European Society of Cardiology (ESC) 2021 Guidelines on Cardiac Pacing and CRT ( figure 1). We primarily aimed to evaluate the adequacy of CRT implementation amongst patients with heart failure reduced ejection fraction (HFrEF) and CD in our current practice. The secondary goals included evaluating the time taken to maximise heart failure medications and to recommend CRT implant in relation to diagnosis, and the reasons for non-implant or delay.Results Out of 248 patients screened, 12% (29) met the criteria for CRT. Amongst those indicated, CRT implants were received by 6/29 patients (21%). The median time from heart failure diagnosis to achieving optimised medical therapy (OMT) was 17.7 months, while the median time from OMT to device implant was 6.9 months ( table 2). Common reasons for no CRT implant or significant implant delay despite being indicated were primarily LVSF and symptomatic recovery by medications alone, multimorbidities, longer time taken to maximise medical therapy and patient declined (table 1). Interestingly, we noted that CRT-indicated patients who achieved LVSF recovery by medications alone, achieved OMT almost twice as earlier than other cohorts, with a median period of 6 months. They settled at higher mean post-treatment LVSF and lower post-treatment BNP at 41.5% and 245pg/ml respectively (figure 1).Conclusions CRT implants in our clinical practice still remains underutilised, with delay in timely application. Nevertheless, our review underscored the need for awareness reinforcement and the potential benefits of early maximization of medical therapy.Abstract 35 Table 1Reasons for no CRT implant. CMR, cardiac magnetic resonance; HFrecEF, heart failure recovered ejection fraction; LBB, left bundle branch; OMT, optimized medical therapy Reasons CRT not received Patients (n) HFrecEF/Asymptomatic 12 Multimorbidities/Frailty 3 Patient Preference (Decline) 2 LBB pacing 2 Awaiting for post-OMT CMR (Determine LVEF) 2 Deceased 2 Total 23 Abstract 35 Table 2Median period to reach OMT from first HFH with mean post-treatment EF and BNP. BNP, brain natriuretic peptide; CMR, cardiac magnetic resonance; EF, ejection fraction; HFH, heart failure hospitalisation; HFrecEF, heart failure recovered ejection fraction; LBB, left bundle branch; OMT, optimised medical therapy Group (n) Median Period to Reach OMT (mths) Mean Post-treatment EF Mean Post-treatment BNP (pg/ml) CRT (6) 17.7 24.7 846 No CRT (9) 11.2 26.9 3188 HFrecEF achieved by OMT alone (13) 6 41.5 245 Abstract 35 Figure 1Indications of CRT per ESC 2021 in relation to other main trials. AF, atrial fibrillation; AVN, atrioventricular node; AVB, atrioventricular block; LVEF, left ventricular ejaculation fraction. *>95% of biventricular pacing is needed if atrioventricular node ‘ablation is not performedAbstract 35 Figure 2Patient outcome. AF, atrial fibrillation; CRT, cardiac resynchronisation therapy; EF, ejection fraction; HFpEF, heart failure preserved ejection fraction; HFU, Heart Failure Unit; [CD, implantable cardiac defibrillator; LY, left ventricular; OMT, optimised medical therapy; RBBB, right bundle branch block",
  "authors": [
    {
      "affiliations": [
        "University College Dublin, Dublin, Ireland"
      ],
      "name": "C Her Yi Ling"
    },
    {
      "affiliations": [
        "St. Vincent’s University Hospital, Dublin, Ireland"
      ],
      "name": "Ú Buckley"
    },
    {
      "affiliations": [
        "University College Dublin, Dublin, Ireland",
        "St. Vincent’s University Hospital, Dublin, Ireland",
        "Heart Failure Unit, St. Michael’s Hospital Dún Laoghaire, Dublin, Ireland"
      ],
      "name": "K McDonald"
    }
  ],
  "title": "35 Cardiac resynchronization therapy: an underutilised treatment modality amongst patients with HFREF and cardiac dyssynchrony",
  "uid": "e617aa64-e058-5f57-8bed-1dd0e72d40ad"
}