Background Timely and accurate detection of pericardial effusion and assessment cardiac tamponade remain challenging and highly operator dependent. Objectives Artificial intelligence has advanced many echocardiographic assessments, and we aimed to develop and validate a deep learning model to automate the assessment of pericardial effusion severity and cardiac tamponade from echocardiogram videos. Methods We developed a deep learning model (EchoNet Pericardium) using temporalspatial convolutional neural networks to automate pericardial effusion severity grading and tamponade detection from echocardiography videos. The model was trained using a retrospective dataset of 1,427,660 videos from 85,380 echocardiograms at Cedars Sinai Medical Center (CSMC) to predict PE severity and cardiac tamponade across individual echocardiographic views and an ensemble approach combining predictions from five standard views. External validation was performed on 33,310 videos from 1,806 echocardiograms from Stanford Healthcare (SHC). Results In the held out CSMC test set, EchoNet Pericardium achieved an AUC of 0.900 (95% CI: 0.884 to 0.916) for detecting moderate or larger pericardial effusion, 0.942 (95% CI: 0.917 to 0.964) for large pericardial effusion, and 0.955 (95% CI: 0.939 to 0.968) for cardiac tamponade. In the SHC external validation cohort, the model achieved AUCs of 0.869 (95% CI: 0.794 to 0.933) for moderate or larger pericardial effusion, 0.959 (95% CI: 0.945 to 0.972) for large pericardial effusion, and 0.966 (95% CI: 0.906 to 0.995) for cardiac tamponade. Subgroup analysis demonstrated consistent performance across ages, sexes, left ventricular ejection fraction, and atrial fibrillation statuses. Conclusions Our deep learning-based framework accurately grades pericardial effusion severity and detects cardiac tamponade from echocardiograms, demonstrating consistent performance and generalizability across different cohorts. This automated tool has the potential to enhance clinical decision-making by reducing operator dependence and expediting diagnosis.

The authors have declared no competing interest.

This work is funded by NIH NHLBI grants R00HL157421, R01HL173526, and R01HL173487 to D.O.

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

The institutional review boards at Cedars-Sinai Medical Center and Stanford HealthCare approved this study.

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I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).

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I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable.

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The dataset of videos and reports used to train EchoNet-Pericardium is not publicly available due to its potentially identifiable nature.