Department of Radiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, No. 160 Pujian Road, Shanghai, 200127, People's Republic of China.
Department of Radiology, Longyan First Hospital, Affiliated to Fujian Medical University, Longyan, 364000, People's Republic of China.
Eur Radiol. 2024 Aug;34(8):4883-4896. doi: 10.1007/s00330-023-10561-y. Epub 2024 Jan 8.
The present study aimed to investigate the incremental prognostic value of the right ventricular fractal dimension (FD), a novel marker of myocardial trabecular complexity by cardiac magnetic resonance (CMR) in patients with arrhythmogenic cardiomyopathy (ACM).
Consecutive patients with ACM undergoing CMR were followed up for major cardiac events, including sudden cardiac death, aborted cardiac arrest, and appropriate implantable cardioverter defibrillator intervention. Prognosis prediction was compared by Cox regression analysis. We established a multivariable model supplemented with RV FD and evaluated its discrimination by Harrell's C-statistic. We compared the category-free, continuous net reclassification improvement (cNRI) and integrated discrimination index (IDI) before and after the addition of FD.
A total of 105 patients were prospectively included from three centers and followed up for a median of 60 (48, 66) months; experienced 36 major cardiac events were recorded. Trabecular FD displayed a strong unadjusted association with major cardiac events (p < 0.05). In the multivariable Cox regression analysis, RV maximal apical FD maintained an independent association with major cardiac events (hazard ratio, 1.31 (1.11-1.55), p < 0.002). The Hosmer-Lemeshow goodness of fit test displayed good fit (X = 0.68, p = 0.99). Diagnostic performance was significantly improved after the addition of RV maximal apical FD to the multivariable baseline model, and the continuous net reclassification improvement increased 21% (p = 0.001), and the integrated discrimination index improved 16% (p = 0.045).
In patients with ACM, CMR-assessed myocardial trabecular complexity was independently correlated with adverse cardiovascular events and provided incremental prognostic value.
The application of FD values for assessing RV myocardial trabeculae may become an accessible and promising parameter in monitoring and early diagnosis of risk factors for adverse cardiovascular events in patients with ACM.
• Ventricular trabecular morphology, a novel quantitative marker by CMR, has been explored for the first time to determine the severity of ACM. • Patients with higher maximal apical fractal dimension of RV displayed significantly higher cumulative incidence of major cardiac events. • RV maximal apical FD was independently associated with major cardiac events and provided incremental prognostic value in patients with ACM.
本研究旨在探讨右心室分形维数（FD）作为心肌小梁复杂性的新标志物在致心律失常性心肌病（ACM）患者中的预后价值。
连续纳入接受心脏磁共振（CMR）检查的 ACM 患者，进行主要心脏不良事件（包括心源性猝死、心脏骤停和适当的植入式心脏复律除颤器干预）的随访。采用 Cox 回归分析比较预后预测。我们建立了一个补充 RV FD 的多变量模型，并通过 Harrell 的 C 统计量评估其判别能力。我们比较了 FD 加入前后无分类连续净重新分类改善（cNRI）和综合判别指数（IDI）。
前瞻性纳入了来自三个中心的 105 例患者，中位随访时间为 60（48、66）个月；记录了 36 例主要心脏不良事件。小梁 FD 与主要心脏不良事件具有很强的未调整相关性（p < 0.05）。在多变量 Cox 回归分析中，RV 最大心尖 FD 与主要心脏不良事件保持独立相关性（危险比 1.31（1.11-1.55），p < 0.002）。Hosmer-Lemeshow 拟合优度检验显示拟合良好（X = 0.68，p = 0.99）。将 RV 最大心尖 FD 添加到多变量基线模型后，诊断性能显著提高，连续净重新分类改善增加了 21%（p = 0.001），综合判别指数提高了 16%（p = 0.045）。
在 ACM 患者中，CMR 评估的心肌小梁复杂性与不良心血管事件独立相关，并提供了额外的预后价值。
评估 RV 心肌小梁的 FD 值的应用可能成为监测和早期诊断 ACM 患者不良心血管事件危险因素的一种可行且有前途的参数。
心室小梁形态学是一种新的 CMR 定量标志物，首次用于确定 ACM 的严重程度。
右心室最大心尖 FD 值较高的患者，其主要心脏不良事件的累积发生率显著升高。
RV 最大心尖 FD 与主要心脏不良事件独立相关，并在 ACM 患者中提供了额外的预后价值。
