{
  "abstract": "Background Pulmonary arterial hypertension (PAH) treatment is guided by mortality risk, commonly estimated using COMPERA 2.0, but the cardiac phenotype driving risk escalation is less well defined. We aimed to quantify the association between cardiac MRI-derived haemodynamic metrics with COMPERA 2.0 score.Methods We studied consecutive patients with PAH from the ASPIRE registry undergoing cardiac MRI and COMPERA 2.0 assessment. MRI images were analysed using an in-house machine learning algorithm to derive time-dependent chamber volumes. Metrics included left ventricular stroke volume index, right ventricular (RV) ejection fraction, RV end-systolic volume index, RV mass, atrial areas, and septal angle. Standardised domain scores were compared across strata using linear regression modelling COMPERA class as an ordinal trend, adjusted for age and sex.Results We included 753 patients. Early clinical worsening (COMPERA 1→2) was characterised by reduced stroke volume and right atrial dilation (β=0.245, p<0.0001 and β=0.159, p<0.0001 respectively). With advancing risk (COMPERA 2→4) right ventricular maladaptation emerged as significant, including progressive RV hypertrophy, dilation and systolic impairment (all p<0.0001). RV ejection fraction demonstrated the greatest overall variation across COMPERA 2 strata. In contrast, maximal septal angle and left atrial area were not associated with clinical risk progression (figure 1).Conclusions PAH risk escalation maps onto a hierarchical MRI phenotype, with early stroke volume impairment and right atrial dilation followed by progressive RV maladaptation. MRI provides a mechanistic framework linking clinical risk to cardiac phenotype in PAH. The incremental prognostic value of MRI augmented COMPERA 2.0 warrants evaluation. When assessing patients pulmonary arterial hypertension, which of the following changes is typical of early stage disease?1. Reduced RV ejection fraction2. RV dilation3. Increased ventricular septal angle4. Reduction in stroke volume5. Reduced right atrial volumeAnswer: Reduction in stroke volumeAbstract 17 Figure 1Reduced RV ejection fraction and RV dilation are characteristic of later stage disease. Ventricular septal angle is also characteristic of late stage disease and was not associated with clinical severity in our study. Reduced right atrial volume is incorrect as right atrial dilation is characteristic of disease progression.",
  "authors": [
    {
      "affiliations": [
        "University of Sheffield Sheffield Teaching Hospitals"
      ],
      "name": "Daniel J Taylor"
    },
    {
      "affiliations": [
        "University of Sheffield Sheffield Teaching Hospitals"
      ],
      "name": "Samer Alabed"
    },
    {
      "affiliations": [
        "University of Sheffield Sheffield Teaching Hospitals"
      ],
      "name": "Alireza Hokmabadi"
    },
    {
      "affiliations": [
        "University of Sheffield Sheffield Teaching Hospitals"
      ],
      "name": "Hamza Zafar"
    },
    {
      "affiliations": [
        "University of Sheffield Sheffield Teaching Hospitals"
      ],
      "name": "Alex MK Rothman"
    },
    {
      "affiliations": [
        "University of Sheffield Sheffield Teaching Hospitals"
      ],
      "name": "Michael J Sharkey"
    },
    {
      "affiliations": [
        "University of Sheffield Sheffield Teaching Hospitals"
      ],
      "name": "Krit Dwivedi"
    },
    {
      "affiliations": [
        "University of Sheffield Sheffield Teaching Hospitals"
      ],
      "name": "Abdul Hameed"
    },
    {
      "affiliations": [
        "University of Sheffield Sheffield Teaching Hospitals"
      ],
      "name": "Athanasios Charalampopoulos"
    },
    {
      "affiliations": [
        "University of Sheffield Sheffield Teaching Hospitals"
      ],
      "name": "Roger Thompson"
    },
    {
      "affiliations": [
        "University of Sheffield Sheffield Teaching Hospitals"
      ],
      "name": "Robin Condliffe"
    },
    {
      "affiliations": [
        "University of Sheffield Sheffield Teaching Hospitals"
      ],
      "name": "David G Kiely"
    },
    {
      "affiliations": [
        "University of Sheffield Sheffield Teaching Hospitals"
      ],
      "name": "Andy J Swift"
    }
  ],
  "title": "17 Harmonising pulmonary arterial hypertension risk stratification with MRI-derived cardiac phenotyping",
  "uid": "e46367bf-b26b-54ed-a14e-005f2a1938ad"
}