Deep Learning-Based Algorithm for Detecting Aortic Stenosis Using Electrocardiography

Abstract

Background Severe, symptomatic aortic stenosis (AS) is associated with poor prognoses. However, early detection of AS is difficult because of the long asymptomatic period experienced by many patients, during which screening tools are ineffective. The aim of this study was to develop and validate a deep learning-based algorithm, combining a multilayer perceptron and convolutional neural network, for detecting significant AS using ECGs. Methods and Results This retrospective cohort study included adult patients who had undergone both ECG and echocardiography. A deep learning-based algorithm was developed using 39 371 ECGs. Internal validation of the algorithm was performed with 6453 ECGs from one hospital, and external validation was performed with 10 865 ECGs from another hospital. The end point was significant AS (beyond moderate). We used demographic information, features, and 500-Hz, 12-lead ECG raw data as predictive variables. In addition, we identified which region had the most significant effect on the decision-making of the algorithm using a sensitivity map. During internal and external validation, the areas under the receiver operating characteristic curve of the deep learning-based algorithm using 12-lead ECG for detecting significant AS were 0.884 (95% CI, 0.880-0.887) and 0.861 (95% CI, 0.858-0.863), respectively; those using a single-lead ECG signal were 0.845 (95% CI, 0.841-0.848) and 0.821 (95% CI, 0.816-0.825), respectively. The sensitivity map showed the algorithm focused on the T wave of the precordial lead to determine the presence of significant AS. Conclusions The deep learning-based algorithm demonstrated high accuracy for significant AS detection using both 12-lead and single-lead ECGs.

Keywords: aortic valve stenosis; deep learning; electrocardiography.

Figure 1

Study flowchart.

Figure 2

ECG data and artificial intelligence algorithm. AFIB indicates atrial fibrillation; AFL, atrial flutter; QTc, corrected QT interval; and 2D, 2‐dimensional.

Figure 3

Performance of artificial intelligence algorithms for detecting aortic stenosis. AUC indicates area under the receiver operating characteristic curve; CNN, convolutional neural network; MLP, multilayer perceptron; and ROC, receiver operating characteristic.

Figure 4

Sensitivity map for confirming the region associated with prediction of aortic stenosis (AS). The sensitivity map showed the convolutional neural network's (CNN's) region of algorithm attention for determining the presence of AS. The most important region is in yellow, and the least important region is in black. Because the number of filters for the first convolutional layer was 64, the sensitivity map described the region of importance for determining the presence of AS as grade 64. We visualized grade 0 as black and grade 64 as yellow. The sensitivity map showed the initial area of T wave in V2–V5 as the most important region used by the developed CNN algorithm for the decision.