The School of Biological Science and Medical Engineering, Beihang University, Beijing, China.
Department of Cardiology, The Second Medical Center of Chinese PLA General Hospital, Beijing, China.
Echocardiography. 2023 Nov;40(11):1205-1215. doi: 10.1111/echo.15696. Epub 2023 Oct 8.
Left ventricular pressure-volume (LV-PV) loops provide comprehensive characterization of cardiovascular system in both health and disease, which are the essential element of the hemodynamic evaluation of heart failure (HF). This study attempts to achieve more detailed HF classifications by non-invasive LV-PV loops from echocardiography and analyzes contribution of parameters to HF classifications.
Firstly, non-invasive PV loops are established by time-varying elastance model where LV volume curves were extracted from apical-four-chambers view of echocardiographic videos. Then, 16 parameters related to cardiac structure and functions are automatically acquired from PV loops. Next, we applied six machine learning (ML) methods to divide four categories. On this premise, we choose the best performing classifier among machine learning approaches for feature ranking. Finally, we compare the contributions of different parameters to HF classifications.
By the experimental, the PV loops were successfully acquired in 1076 cases. When single left ventricular ejection fraction (LVEF) is used for HF classifications, the accuracy of the model is 91.67%. When added parameters extracted from ML-derived LV-PV loops, the classification accuracy is 96.57%, which improved by 5.1%. Especially, our parameters have a great improvement in the classification of non-HF controls and heart failure with preserved ejection fraction (HFpEF).
We successfully presented the classification of HF by machine derived non-invasive LV-PV loops, which has the potential to improve the diagnosis and management of heart failure in clinic. Moreover, ventriculo-arterial (VA) coupling and ventricular efficiency were demonstrated important factors for ML-based HF classification model besides LVEF.
左心室压力-容积(LV-PV)环提供了健康和疾病状态下心血管系统的全面特征描述,是心力衰竭(HF)血流动力学评估的基本要素。本研究试图通过超声心动图的无创性 LV-PV 环实现更详细的 HF 分类,并分析参数对 HF 分类的贡献。
首先,通过时变弹性质模型建立无创性 PV 环,从超声心动图视频的心尖四腔视图中提取 LV 容积曲线。然后,从 PV 环中自动获取 16 个与心脏结构和功能相关的参数。接下来,我们应用 6 种机器学习(ML)方法对 4 个类别进行分类。在此前提下,我们选择机器学习方法中性能最佳的分类器进行特征排序。最后,我们比较不同参数对 HF 分类的贡献。
通过实验,成功获取了 1076 例患者的 PV 环。当单独使用左心室射血分数(LVEF)进行 HF 分类时,模型的准确率为 91.67%。当加入从 ML 衍生的 LV-PV 环中提取的参数时,分类准确率提高到 96.57%,提高了 5.1%。特别是,我们的参数在非 HF 对照组和射血分数保留性心力衰竭(HFpEF)的分类中具有很大的改善。
我们成功地提出了基于机器的无创性 LV-PV 环对 HF 的分类,这有可能改善临床心力衰竭的诊断和管理。此外,除了 LVEF 之外,心室动脉(VA)偶联和心室效率被证明是基于 ML 的 HF 分类模型的重要因素。