Screening for Left Ventricular Dysfunction in Sepsis Using a Smartphone ECG Analysis Application: A Multicenter Validation Study.

BACKGROUND

Sepsis-induced left ventricular (LV) dysfunction complicates fluid resuscitation, increasing the risk of pulmonary edema and worsening outcomes. Echocardiographic assessment is often delayed, and natriuretic peptides such as N-terminal pro-B-type natriuretic peptide (NT-proBNP) have limited diagnostic accuracy in this setting. We evaluated a smartphone-based electrocardiogram (ECG) analysis application for screening LV dysfunction in patients with sepsis.

METHODS

In this multicenter retrospective observational study, we included 425 adult sepsis patients from three university hospitals who underwent both a 12-lead ECG and transthoracic echocardiography within 72 hours of emergency department admission. ECG images displayed on a monitor were photographed and analyzed using an artificial intelligence (AI)-based smartphone application (ECG Buddy™), which generated a quantitative digital biomarker for LV dysfunction (quantitative electrocardiogram scores for LV dysfunction [QCG-LVDys]). LV dysfunction was defined as a left ventricular ejection fraction ≤ 40%. The diagnostic performance of QCG-LVDys for detecting LV dysfunction was evaluated using area under the receiver operating characteristic curve (ROC-AUC). A predefined comparison with NT-proBNP was performed in the single center where NT-proBNP was routinely measured.

RESULTS

In the overall multicenter cohort, QCG-LVDys showed high diagnostic performance for LV dysfunction, with an ROC-AUC of 0.901. Using an optimized threshold (37.35), QCG-LVDys achieved a sensitivity of 89.6%, specificity of 75.1%, and negative predictive value (NPV) of 97.5%. In the NT-proBNP subset, QCG-LVDys outperformed NT-proBNP (ROC-AUC 0.911 vs. 0.637, P < 0.001). Higher QCG-LVDys values were associated with increased lactate levels (P = 0.002) and 28-day in-hospital mortality (P < 0.001).

CONCLUSION

AI-driven ECG analysis via a smartphone app provided a rapid, accessible, and accurate screening tool for LV dysfunction in sepsis and outperformed NT-proBNP. Its high NPV suggests potential utility for early risk stratification and for informing cautious hemodynamic management, although prospective studies are needed to define its role in sepsis treatment protocols.