This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Cheng, T. O. Articles by Seward, J. B. Search for Related Content PubMed PubMed Citation Articles by Cheng, T. O. Articles by Seward, J. B. Related Collections Echocardiography Pediatric and congenital heart disease, including cardiovascular surgery Embolic stroke Risk Factors for Stroke

(Circulation. 2000;101:e210.)
© 2000 American Heart Association, Inc.

Circulation Electronic Pages

Paradoxical Embolism as a Principal Cause of Stroke in Atrial Septal Aneurysm

Tsung O. Cheng, MD

Professor of Medicine George Washington University, Washington, DC

	Introduction

 
To the Editor:

The report from the Stroke Prevention: Assessment of Risk in a Community (SPARC) study¹ stating that atrial septal aneurysm (ASA) is associated with an increased risk of stroke is important for 2 reasons. (1) It definitively establishes the prevalence of ASA in the general population at 2.2%. The true prevalence of ASA was underestimated before the routine use of echocardiography, especially transesophageal echocardiography.² (2) It supports the previous conjecture that paradoxical embolism is the predominant mechanism of cardioembolism in ASA.³

Although 2 previous multicenter studies^{4 5} suggested paradoxical embolism as a possibility among several other mechanisms, including thrombus formation in the ASA, associated mitral valve prolapse, associated mitral stenosis, and supraventricular tachyarrhythmias, this study was the first to prove conclusively that paradoxical embolism is the principal mechanism for stroke in patients with ASA. This has obvious and important therapeutic implications.

	References

 
1. Agmon Y, Khandheria BK, Meissner I, et al. Frequency of atrial septal aneurysms in patients with cerebral ischemic events. Circulation. 1999;99:1942–1944.[Abstract/Free Full Text]

2. Pearson AC, Labovitz AJ, Tatineni S, et al. Superiority of transesophageal echocardiography in detecting cardiac source of embolism in patients with cerebral ischemia of uncertain etiology. J Am Coll Cardiol. 1991;17:66–72.[Abstract]

3. Cheng TO. Atrial septal aneurysm as a "newly discovered" cause of stroke in patients with mitral valve prolapse. Am J Cardiol. 1991;67:327–328.

4. Mügge A, Daniel WG, Angermann C, et al. Atrial septal aneurysm in adult patients: a multicenter study using transthoracic and transesophageal echocardiography. Circulation. 1995;91:2785–2792.[Abstract/Free Full Text]

5. Marazanof M, Roudaut R, Cohen A, et al. Atrial septal aneurysm: morphologic characteristics in a large population: pathological associations: a French multicenter study on 259 patients investigated by transesophageal echocardiography. Int J Cardiol. 1995;52:59–65.[Medline] [Order article via Infotrieve]

Response

Yoram Agmon, MD; Bijoy K. Khandheria, MD; Irene Meissner, MD; Federico Gentile, MD; Jack P. Whisnant, MD; JoRean D. Sicks, MS; W. Michael O’Fallon, PhD; Jody L. Covalt, RN; David O. Wiebers, MD; James B. Seward, MD

Mayo Clinic, Rochester, Minn

	Introduction

 
We appreciate Dr Cheng’s interest in the Stroke Prevention: Assessment of Risk in a Community (SPARC) study and the recent application of its data in establishing the role of atrial septal aneurysm (ASA) as a source of cardioembolism.^R1 A major contribution of the SPARC study is the definition of the prevalence of various cardiac pathologies (eg, ASA) in a large representative sample of the population, as determined by transesophageal echocardiography (TEE). The frequency of ASA observed in the SPARC population (2.2%) was similar to the frequency found in a large autopsy study^R2 but lower than that in previously reported TEE studies.^R3 These differences are related to the nature . . . [Full Text of this Article]