Transesophageal echocardiography (TEE) is the imaging modality of choice for doctors treating patients with ischemic stroke, but cardiac CT is just as effective at predicting recurrent strokes, according to a study published in the March issue of Radiology.
Studies have shown that between 9 and 14 percent of patients who suffer a stroke have another within two years’ time, with stroke recurrence resulting in substantial morbidity and mortality among stroke patient populations. “Currently, TEE is considered the reference standard modality for the identification of the cardiac and aortogenic source of embolism,” wrote lead author Kyeho Lee, MD, and colleagues at the Yonsei University of Medicine in Seoul, Korea. “However, TEE is a relatively invasive test and requires special skills for proper performance and interpretation, which is not always feasible in acute stroke settings.”
For this reason, Lee and his team decided to compare the effectiveness of TEE as a predictive tool for recurrence in patients with ischemic stroke with another imaging modality, CT. To do so, they enrolled 374 men and women with ischemic stroke who had undergone TEE and cardiac CT screening at their hospital between January 2011 and January 2012. Imaging results were assessed for a variety of cardioembolic sources, with the study’s primary end point being stroke recurrence and the prognostic abilities of the two screening modalities.
Twenty-eight of the patients had stroke recurrence in the two-year period following their initial strokes. The researchers analyzed the information from their scans and found that complex aortic plaque was associated with increased risk of recurrence, with CT proving equally as effective as TEE as a predictive tool for recurrent strokes.
“Our study showed that complex aortic plaque identified by using CT is a strong and independent predictor of recurrent stroke,” wrote Lee et al. “In addition, our study proved the equivalence of CT to TEE in the prediction of stroke recurrence. When the prognoses determined with TEE and CT were compared, TEE was not significantly superior in the prediction of stroke recurrence.”
The authors said more studies are needed to determine the prognostic abilities of another imaging modality, MR, in determining potential sources of cardioembolism in stroke patients.
The researchers believe there is promise for CT as a prognostic tool in the treatment of ischemic stroke and the prevention of recurrence. “CT has some advantages in the evaluation of aortic plaque because of the ability to reconstruct high-quality multidimensional images and enable a retrospective review with the same quality of reproducibility,” wrote Lee and colleagues. “Because the risk of recurrence is highly dependent on underlying causes, an early determination of the etiologic factors of ischemic stroke is essential for proper patient management.”