Brain Computed Tomography Perfusion Facilitates Early Prediction of Neurological Outcomes in Patients Suspected of Ischemic Cerebral Conditions after Cardiac Surgery.

OBJECTIVES

This study aimed to investigate the value of brain computed tomography perfusion (CTP) imaging in predicting neurological outcomes early in patients with suspected ischemic cerebral events after cardiac surgery.

DESIGN

Retrospective observational study.

SETTING

A university teaching hospital.

PARTICIPANTS

Patients presenting with postoperative neurological symptoms suspected of ischemic stroke following cardiac surgery from June 2020 to January 2024.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Non-contrast computed tomography (NCCT) scans at initial evaluation and follow-up were evaluated using the semiquantitative Alberta Stroke Programme Early CT Score (ASPECTS). On CTP images, the volume of time to maximum (Tmax) >6.0 seconds and volume of relative cerebral blood flow (rCBF) <30% were calculated. The primary outcome was severe disability, defined as a Modified Rankin Scale (mRs) score ≥4 at discharge. In total, 109 patients were included. The presence of volume of Tmax >6.0 seconds (R = 0.05, p = 0.006) and volume of rCBF <30% (R = 0.18, p < 0.001) positively correlated with mRs at discharge. The areas under the ROC curves for ASPECTS-1, volume of Tmax >6 seconds, and volume of rCBF <30% were 0.62 (95% CI: 0.52-0.71, p = 0.009), 0.67 (95% CI: 0.57-0.76, p < 0.001), and 0.73 (95% CI: 0.64-0.81, p < 0.001), respectively. The volume of rCBF <30% demonstrated the highest accuracy (0.76, 95% CI: 0.64-0.86, p < 0.001), and a similar accuracy was only achieved by the NCCT scan in the follow-up (0.79, 95% CI: 0.67-0.88, p < 0.001).

CONCLUSIONS

In patients with suspected ischemic cerebral events after cardiac surgery, brain CTP, particularly the assessment of the volume of rCBF <30%, demonstrates accuracy in predicting severe neurological disability compared to the initial NCCT scan. CTP may serve as an early and reliable prognostic tool to guide clinical decision-making in these patients.