Can a CT scan show hidden lung water that predicts bad outcomes in STEMI?

In STEMI patients, even those who appear stable (Killip class 1, meaning no signs of heart failure), fluid can accumulate in the lungs without obvious symptoms. This is called subclinical pulmonary congestion, measured as extravascular lung water (EVLW) on CT. Research shows that CT-detected EVLW can predict worse outcomes, including in-hospital major adverse cardiovascular events (MACE), beyond standard risk scores like GRACE.

What the research says

A retrospective study of 249 Killip class 1 STEMI patients who had CT before primary PCI found that those who experienced in-hospital MACE had significantly higher EVLW (24.24% vs. 21.36%) and higher GRACE scores ⁵. Adding EVLW to the GRACE score improved prediction: the area under the ROC curve increased from 0.656 to 0.754, and net reclassification improvement was 0.491, meaning it correctly reclassified about 49% of patients into higher or lower risk categories ⁵. This suggests that CT-detected lung water provides independent prognostic information beyond traditional risk factors. Other studies have focused on different predictors of poor outcomes after STEMI, such as microvascular dysfunction ¹, myocardial hypoperfusion ², and acute heart failure ³, but none directly address CT lung water. The CT method is noninvasive and can be performed quickly, potentially helping clinicians identify high-risk patients who might benefit from closer monitoring or early intervention.

What to ask your doctor

• Could a CT scan to check for lung water be helpful in my case after a STEMI?
• What does my extravascular lung water measurement mean for my risk of complications?
• How does CT-detected lung water compare to other tests like echocardiography or chest X-ray for predicting outcomes?
• If I have hidden lung water, what treatments or monitoring would you recommend?
• Are there any risks or downsides to having a CT scan for this purpose?