National Pulmonary Hypertension Service, Royal Free London NHS Foundation Trust, Pond Street, London NW3 2QG, UK.
Department of Cardiac MRI, Royal Free London NHS Foundation Trust, Pond Street, London NW3 2QG, UK.
Eur Heart J Cardiovasc Imaging. 2024 Nov 27;25(12):1712-1720. doi: 10.1093/ehjci/jeae177.
Systemic sclerosis complicated by pulmonary arterial hypertension (SSc-PAH) is a rare condition with poor prognosis. The majority of patients are categorized as intermediate risk of mortality. Cardiovascular magnetic resonance (CMR) is well placed to reproducibly assess right heart size and function, but most patients with SSc-PAH have less overtly abnormal right ventricles than other forms of PAH. The aim of this study was to assess if exercise CMR measures of cardiac size and function could better predict outcome in patients with intermediate risk SSc-PAH compared with resting CMR.
Fifty patients with SSc-PAH categorized as intermediate risk underwent CMR-augmented cardiopulmonary exercise testing. Most patients had normal CMR-defined resting measures of right ventricular (RV) size and function. Nine (18%) patients died during a median follow-up period of 2.1 years (range 0.1-4.6). Peak exercise RV indexed end-systolic volume (ESVi) was the only CMR metric to predict prognosis on stepwise Cox regression analysis, with an optimal threshold < 39 mL/m2 to predict favourable outcome. Intermediate-low risk patients with peak RVESVi < 39 mL/m2 had significantly better survival than all other combinations of intermediate-low/-high risk status and peak RVESVi< or ≥39 mL/m2. In our cohort, ventilatory efficiency and resting oxygen consumption (VO2) were predictive of mortality, but not peak VO2, peak cardiac output, or peak tissue oxygen extraction.
Exercise CMR assessment of RV size and function may help identify SSc-PAH patients with poorer prognosis amongst intermediate risk cohorts, even when resting CMR appears reassuring, and could offer added value to clinical PH risk stratification.
系统性硬化症合并肺动脉高压（SSc-PAH）是一种预后不良的罕见疾病。大多数患者被归类为中危死亡率。心血管磁共振（CMR）非常适合重复评估右心大小和功能，但大多数 SSc-PAH 患者的右心室比其他形式的 PAH 更不明显异常。本研究旨在评估运动 CMR 测量的心脏大小和功能是否能更好地预测中危 SSc-PAH 患者的预后，与静息 CMR 相比。
50 例被归类为中危的 SSc-PAH 患者接受了 CMR 增强心肺运动测试。大多数患者的静息右心室（RV）大小和功能的 CMR 定义正常。中位数随访期为 2.1 年（范围 0.1-4.6），有 9 例（18%）患者死亡。峰值运动 RV 指数末收缩容积（ESVi）是逐步 Cox 回归分析中唯一预测预后的 CMR 指标，最佳阈值<39mL/m2 可预测良好的结果。峰值 RVESVi<39mL/m2 的中低危患者的生存率明显优于其他中低/高危状态和峰值 RVESVi<或≥39mL/m2 的组合。在我们的队列中，通气效率和静息耗氧量（VO2）是死亡的预测因素，但不是峰值 VO2、峰值心输出量或峰值组织氧摄取量。
运动 CMR 评估 RV 大小和功能可能有助于识别中危队列中预后较差的 SSc-PAH 患者，即使静息 CMR 看起来令人安心，并且可能为临床 PH 风险分层提供额外的价值。
