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Published on: December 11, 2019
Deep learning of ECG waveforms for diagnosis of heart failure with a reduced left ventricular ejection fraction
JungMin Choi1,2, Sungjae Lee3, Mineok Chang3
1Department of Internal Medicine, Seoul National University Hospital, Seoul, Republic of Korea.
Insights
A deep learning algorithm, DeepECG-HFrEF, accurately identifies heart failure with reduced ejection fraction (HFrEF) using electrocardiograms. This tool aids in recognizing left ventricular systolic dysfunction and predicting higher mortality risk in acute heart failure patients.
Area of Science:
- Cardiology
- Artificial Intelligence
- Medical Diagnostics
Background:
- Heart failure with reduced ejection fraction (HFrEF) significantly impacts patient survival.
- Accurate identification of HFrEF is crucial for timely intervention and management.
- Current diagnostic methods may have limitations, especially in resource-limited settings.
Purpose of the Study:
- To evaluate the performance of a deep learning algorithm, DeepECG-HFrEF, in identifying HFrEF from electrocardiograms (ECGs).
- To assess the clinical implications of DeepECG-HFrEF, including its association with patient survival.
- To determine the utility of DeepECG-HFrEF in diagnosing left ventricular systolic dysfunction (LVSD).
Main Methods:
- The DeepECG-HFrEF algorithm was trained to detect LVSD (ejection fraction < 40%).
- Performance was assessed using the area under the receiver operating characteristic curve (AUC) in a cohort of acute heart failure patients.
- Five-year mortality was analyzed using the Kaplan-Meier method based on algorithm classification.
Main Results:
- The study included 1291 ECGs from 690 patients (mean age 67.8 years, 56% men).
- DeepECG-HFrEF achieved an AUC of 0.844 for identifying HFrEF in acute symptomatic heart failure patients.
- Patients classified as HFrEF (+) by the algorithm demonstrated significantly lower 5-year survival rates (log-rank p < 0.001).
Conclusions:
- The DeepECG-HFrEF algorithm demonstrates acceptable performance in discriminating HFrEF within a real-world clinical setting.
- The algorithm's classification of HFrEF is associated with increased mortality, highlighting its prognostic value.
- DeepECG-HFrEF shows potential for aiding in LVSD identification and risk stratification, particularly in resource-limited environments.
Abstract:
The performance and clinical implications of the deep learning aided algorithm using electrocardiogram of heart failure (HF) with reduced ejection fraction (DeepECG-HFrEF) were evaluated in patients with acute HF. The DeepECG-HFrEF algorithm was trained to identify left ventricular systolic dysfunction (LVSD), defined by an ejection fraction (EF) < 40%. Symptomatic HF patients admitted at Seoul National University Hospital between 2011 and 2014 were included. The performance of DeepECG-HFrEF was determined using the area under the receiver operating characteristic curve (AUC) values. The 5-year mortality according to DeepECG-HFrEF results was analyzed using the Kaplan-Meier method. A total of 690 patients contributing 18,449 ECGs were included with final 1291 ECGs eligible for the study (mean age 67.8 ± 14.4 years; men, 56%). HFrEF (+) identified an EF < 40% and HFrEF (-) identified EF ≥ 40%. The AUC value was 0.844 for identifying HFrEF among patients with acute symptomatic HF. Those classified as HFrEF (+) showed lower survival rates than HFrEF (-) (log-rank p < 0.001). The DeepECG-HFrEF algorithm can discriminate HFrEF in a real-world HF cohort with acceptable performance. HFrEF (+) was associated with higher mortality rates. The DeepECG-HFrEF algorithm may help in identification of LVSD and of patients at risk of worse survival in resource-limited settings.
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