{
  "abstract": "Background At the time of surgical valve intervention, patients often have remodelling of cardiac chambers including hypertrophy and fibrosis. Indeed, in the absence of symptoms, guidelines often only indicate surgery when significant changes to chamber size and function have occurred. In this project, we investigate if these changes regress after intervention.Methods Patients with aortic stenosis (AS), aortic regurgitation (AR) or mitral regurgitation (MR) who underwent valve replacement between 2017-2019 with echocardiograms before and/or after surgery were selected [ table 1]. Echocardiograms underwent automated analysis with manual review of chamber size parameters including left ventricular (LV) diastolic and systolic dimensions, septal thickness, LV diastolic volume, left atrial (LA) systolic dimension and area. Regression models were constructed to assess the trajectory of each parameter before and after surgery.Results One year post-surgery, MR and AR patients showed significant declines in LV diastolic dimension (– 0.58 cm, p < 0.0001 for MR [figure 1A]; –0.39 cm, p = 0.0101 for AR [figure 2A]) and LV diastolic volume (– 21.37 cm3, p < 0.0001 for MR; –35.29 cm3, p = 0.0028 for AR [figure 2B]). Additionally, LA area decreased for MR (– 2.81 cm2, p = 0.0005 [figure 1B]). LV and LA systolic dimensions were also reduced in MR patients (– 0.27 cm, p = 0.0027 and – 0.23 cm, p = 0.0157, respectively). Five years post-surgery, these statistically significant reductions remained, except that LA systolic dimension and area changes were no longer significant in patients with MR (0.04 cm, p = 0.7039 and – 1.05 cm2, p = 0.2190, respectively). Also, LV diastolic dimension in AR was no longer significantly reduced (– 0.21 cm, p = 0.1239). IVS thickness remained unchanged in MR and AS patients but showed a small increase in AR patients at five years post-surgery (0.14 cm, p = 0.0032). In AS patients, no significant reductions in LV and LA chamber size were observed.Discussion Despite promising results in chamber size post-surgery, a holistic depiction of morphological progression requires accompanying analysis of functional parameters and fibrotic changes. The study limitations included a moderate sample size, limited analysis success rates and the restricted freedom of the regression model.Conclusion This study visualises VHD progression pre- and post-surgery, revealing a general positive shift in cardiac morphology following valve replacement. Future studies should address these limitations in conjunction with assessing for myocardial functional and fibrotic changes to paint a comprehensive micro- and macroscopic picture of VHD disease progression.Abstract 6-007 Table 1Baseline patient characteristics Variables Mitral Regurgitation Aortic Stenosis Aortic Regurgitation Total number of patients, N 44 38 22 Gender Male: 26Female: 18 Male: 22Female: 16 Male: 15Female: 7 Median age (yrs) 69 (IQR, 59–74) 80 (IQR, 71–89) 67 (IQR, 53–77) N for year of operation: 2017 4 3 4 2018 6 2 3 2019 34 33 15 Total number of echocardiograms 274 216 132 Median number of echocardiograms per patient 6 (IQR, 5–7) 5 (IQR, 5–7) 6 (IQR, 4–8) Abstract 6-007 Figure 1Exemplar graphs of time trends of echocardiographic left chamber size parameters across patients with mitral regurgitation (MR). Each plot displays the estimated line of best fit of the regression model (black line) for an exemplar patient with shaded 95% confidence intervals. Individual data points represent raw values from each echocardiogramAbstract 6-007 Figure 2Exemplar graphs of time trends of echocardiographic left chamber size parameters across patients with aortic regurgitation (AR). Each plot displays the estimated line of best fit of the regression model (black line) for an exemplar patient with shaded 95% confidence intervals. Individual data points represent raw values from each echocardiogram",
  "authors": [
    {
      "affiliations": [
        "Imperial College School of Medicine"
      ],
      "name": "A El-Shaboury"
    },
    {
      "affiliations": [
        "National Heart and Lung Institute, Imperial College London",
        "Imperial College Healthcare NHS Trust"
      ],
      "name": "T Ng"
    },
    {
      "affiliations": [
        "National Heart and Lung Institute, Imperial College London",
        "Imperial College Healthcare NHS Trust"
      ],
      "name": "C Stowell"
    },
    {
      "affiliations": [
        "National Heart and Lung Institute, Imperial College London",
        "Imperial College Healthcare NHS Trust"
      ],
      "name": "DP Francis"
    },
    {
      "affiliations": [
        "National Heart and Lung Institute, Imperial College London",
        "Imperial College Healthcare NHS Trust"
      ],
      "name": "MJ Shun-Shin"
    }
  ],
  "title": "6-007 Quantifying the impact of heart valve surgery on time trends in echocardiographic sizes of the cardiac chambers using artificial intelligence",
  "uid": "c3c9a357-7d0f-513c-bb00-b1e3f38f6d74"
}