Practicability and Diagnostic Yield of One-Stop Stroke CT with Delayed-Phase Cardiac CT in Detecting Major Cardioembolic Sources of Acute Ischemic Stroke

Abstract

Purpose Recurrent stroke is considered to increase the incidence of severe disability and death. For correct risk assessment and patient management it is essential to identify the origin of stroke at an early stage. Transthoracic echocardiography (TTE) is the initial standard of care for evaluating patients in whom a cardioembolic source of stroke (CES) is suspected but its diagnostic capability is limited. Transesophageal echocardiography (TEE) is considered as gold standard; however, this approach is time consuming, semi-invasive and not always feasible. We hypothesized that adding a delayed-phase cardiac computed tomography (cCT) to initial multimodal CT might represent a valid alternative to routine clinical echocardiographic work-up. Material and Methods Patients with suspected acute cardioembolic stroke verified by initial multimodal CT and subsequently examined with cCT were included. The cCT was evaluated for presence of major CES and compared to routine clinical echocardiographic work-up. Results In all, 102 patients with suspected acute CES underwent cCT. Among them 60 patients underwent routine work-up with echocardiography (50 TTE and only 10 TEE). By cCT 10/60 (16.7%) major CES were detected but only 4 (6.7%) were identified by echocardiography. All CES observed by echocardiography were also detected by cCT. In 8 of 36 patients in whom echocardiography was not performed cCT also revealed a major CES. Conclusion These preliminary results show the potential diagnostic yield of delayed-phase cCT to detect major CES and therefore could accelerate decision-making to prevent recurrence stroke. To confirm these results larger studies with TEE as the reference standard and also compared to TTE would be necessary.

Diagnostic Yield of ECG-Gated Cardiac CT in theAcute Phase of Ischemic Stroke vsTransthoracic Echocardiography

“…A more recently published retrospective study comparing the diagnostic yield for high-risk sources of embolism of cardiac CT in the acute phase with echocardiography in 60 patients reported a high-risk source of embolism on CT in 10 patients vs 4 on echocardiography. 15 Retrospective studies on CT of the heart or left atrial appendage alone in the acute stroke imaging protocol described rates for left atrial appendage thrombi similar to our results but did not report on other cardiac sources of embolism and did not compare CT findings with echocardiography. 16,33 This study has a number of limitations.…”

“…Cardiac CT can be acquired fast, and data from small-scale retrospective studies suggest that cardiac CT can be incorporated in the acute imaging protocol of stroke patients with a low additional radiation dose. [11][12][13][14][15][16] Moreover, acquiring cardiac CT during the initial stroke imaging protocol can lead to faster diagnosis and improved treatment of cardioembolic stroke while reducing the number of return visits for impaired patients to undergo echocardiography.…”

In Reply: Practicability and Diagnostic Yield of One-Stop Stroke CT with Delayed-Phase Cardiac CT in Detecting Major Cardioembolic Sources of Acute Ischemic Stroke

“…Since the number of CES was limited in the study of Yeo et al. ( n = 3) [ 8 ] compared to our study ( n = 10 [ 1 ]), we think that one strength of our dataset is the increased internal validity regarding the value of non-ECG gated CTA. Moreover, the delayed and ECG-triggered cardiac CT in an acute stroke setting used in our study resulted in higher diagnostic yield and image quality with potential diagnostic benefit.…”

“…We would like to thank Yeo et al. for sharing their valuable insights and thoughts about our work [ 1 ] in their letter to the editor [ 2 ].…”

“…have shown that cardiac CT and transthoracic echocardiography (TTE) have a comparatively high specificity and negative predictive value for CES recurrence [ 13 ]. As TTE is not the preferred diagnostic method to detect an atrial thrombus (which is mostly detected by transesophageal echocardiography, TEE), cardiac CTA may be a valid and even superior alternative to TTE alone, since TEE has other important limitations mentioned in our manuscript [ 1 , 5 ]. This advantage is further emphasized by the fact that TEE is often a limited resource and that immediate CTA is also part of standard operating procedures to identify patients suitable for endovascular treatment [ 14 ].…”