Cost-Effectiveness of Echocardiography after Stroke

15 May 1998 | Volume 128 Issue 10 | Page 872

TO THE EDITOR:

McNamara and colleagues [1] reported on the cost-effectiveness of transesophageal echocardiography (TEE) and the cost advantages over transthoracic echocardiography (TTE) in patients with stroke in normal sinus rhythm. As clinical echocardiographers, we are not as willing to dismiss the role of TTE. In contrast to the 2% to 3% incidence of complications with TEE [2], TTE is not associated with significant adverse reactions. Furthermore, many patients often have a readily identifiable cause apparent on TTE (for example, left ventricular dysfunction, left ventricular thrombus, mitral stenosis), and evidence suggests [3] that newer-generation TTE systems can detect left atrial thrombus with high sensitivity.

In patients with sinus rhythm, absence of clinical heart disease, or normal TTE findings, the incidence of left atrial thrombus is low. In the nine studies selected by McNamara and colleagues that provided this subgroup information (their references 8-14, 17, and 21), only 6 of 736 patients (0.8%) had left atrial thrombus detected by TEE. Of 824 consecutive patients with stroke, peripheral embolism, or transient ischemic attack referred for TEE at the Cleveland Clinic [4], 236 (29%) had sinus rhythm and normal TTE findings; none of these 236 had left atrial thrombus on TEE. Although TEE may be able to identify other associated abnormalities, such as patent foramen ovale or atrial septal aneurysm, more readily than TTE can, the subsequent effect on patient management remains unproven.

We suggest that TTE still be used as the first-line approach. with TEE to follow in a selective fashion (Figure 1). Cost-effectiveness issues require additional formal analysis.

View larger version (15K): [in this window] [in a new window]   Figure 1. Algorithm for use of transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE). *TEE only in select cases.

 

Author and Article Information

Top Author & Article Info References

University of Manitoba; Winnipeg, Manitoba R3A 1R9, Canada

References

Top Author & Article Info References

1. McNamara RL, Lima JA, Whelton PK, Powe NR. Echocardiographic identification of cardiovascular sources of emboli to guide clinical management of stroke: a cost-effectiveness analysis. Ann Intern Med. 1997; 127:773-87.

2. Tam JW, Burwash IG, Ascah KJ, Baird MG, Chan KL. Feasibility and complications of single-plane and biplane versus multiplane transesophageal imaging: a review of 2947 consecutive studies. Can J Cardiol. 1997; 13:81-4.

3. Omran H, Jung W, Wirtz P, Schimpf R, Illien S, Luderitz B. Assessment of left atrial appendage function and detection of thrombi: a prospective study comparing transthoracic and transesophageal echocardiography. Circulation. 1997; 96:1-134.

4. Leung DY, Black IW, Cranney GB, Walsh WF, Crimm RA, Stewart WJ, et al. Selection of patients for transesophageal echocardiography after stroke and systemic embolic events. Role of transthoracic echocardiography. Stroke. 1995; 26:1820-4.

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