基于心音图迁移学习的 CatBoost 模型,使用多个特定领域深度特征融合进行舒张功能障碍识别。
Phonocardiogram transfer learning-based CatBoost model for diastolic dysfunction identification using multiple domain-specific deep feature fusion.
机构信息
Department of Radiology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, 400016, PR China; State Key Laboratory of Ultrasound in Medicine and Engineering, Chongqing Medical University, Chongqing, 400016, China; Medical Data Science Academy, Chongqing Medical University, Chongqing, 400016, China.
Key Laboratory of Biorheology Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing, 400044, PR China.
出版信息
Comput Biol Med. 2023 Apr;156:106707. doi: 10.1016/j.compbiomed.2023.106707. Epub 2023 Feb 20.
Left ventricular diastolic dyfunction detection is particularly important in cardiac function screening. This paper proposed a phonocardiogram (PCG) transfer learning-based CatBoost model to detect diastolic dysfunction noninvasively. The Short-Time Fourier Transform (STFT), Mel Frequency Cepstral Coefficients (MFCCs), S-transform and gammatonegram were utilized to perform four different representations of spectrograms for learning the representative patterns of PCG signals in two-dimensional image modality. Then, four pre-trained convolutional neural networks (CNNs) such as VGG16, Xception, ResNet50 and InceptionResNetv2 were employed to extract multiple domain-specific deep features from PCG spectrograms using transfer learning, respectively. Further, principal component analysis and linear discriminant analysis (LDA) were applied to different feature subsets, respectively, and then these different selected features are fused and fed into CatBoost for classification and performance comparison. Finally, three typical machine learning classifiers such as multilayer perceptron, support vector machine and random forest were employed to compared with CatBoost. The hyperparameter optimization of the investigated models was determined through grid search. The visualized result of the global feature importance showed that deep features extracted from gammatonegram by ResNet50 contributed most to classification. Overall, the proposed multiple domain-specific feature fusion based CatBoost model with LDA achieved the best performance with an area under the curve of 0.911, accuracy of 0.882, sensitivity of 0.821, specificity of 0.927, F1-score of 0.892 on the testing set. The PCG transfer learning-based model developed in this study could aid in diastolic dysfunction detection and could contribute to non-invasive evaluation of diastolic function.
左心室舒张功能障碍检测在心脏功能筛查中尤为重要。本文提出了一种基于心音图(PCG)迁移学习的 CatBoost 模型,用于无创检测舒张功能障碍。短时傅里叶变换(STFT)、梅尔频率倒谱系数(MFCCs)、S 变换和伽马音图被用于对声谱图进行四种不同的表示,以学习二维图像模态下心音图信号的代表性模式。然后,使用迁移学习分别采用四个预先训练的卷积神经网络(CNN),如 VGG16、Xception、ResNet50 和 InceptionResNetv2,从 PCG 声谱图中提取多个特定领域的深度特征。进一步,对不同的特征子集分别应用主成分分析和线性判别分析(LDA),然后融合这些不同选择的特征并将其输入到 CatBoost 中进行分类和性能比较。最后,采用多层感知机、支持向量机和随机森林三种典型的机器学习分类器与 CatBoost 进行比较。通过网格搜索确定了所研究模型的超参数优化。全局特征重要性的可视化结果表明,ResNet50 从伽马音图中提取的深度特征对分类的贡献最大。总的来说,基于多领域特定特征融合的 CatBoost 模型与 LDA 的性能最佳,在测试集上的曲线下面积为 0.911,准确率为 0.882,灵敏度为 0.821,特异性为 0.927,F1 得分为 0.892。本研究开发的基于 PCG 迁移学习的模型可辅助舒张功能障碍检测,并有助于对舒张功能进行无创评估。