Reply
José T. Ortiz-Pérez, MD,
Edwin Wu, MD
201 East Huron, Galter 10-240, Chicago, Illinois 60611
We thank Dr. Danias for his interest in our article (1). Despite the differences in the left ventricular segmentation model applied by Aepfelbacher et al. (2) in their study, we agree that the entire apex more frequently is supplied by the left anterior descending artery (LAD). This finding has also been suggested in other studies in which the authors used nuclear perfusion imaging (3) or coronary computed angiography and magnetic resonance imaging (4). These results reflect the usual distribution of the LAD on angiography which, in most cases, wraps around the apex. Therefore, we agree that these studies should warrant a possible revision of the expected vascular distribution in the 17-segment American Heart Association model.
The coronary supply of segment 12 (midanterolateral wall) remains controversial. Although Aepfelbacher et al. (2) reported that this segment is supplied by the left circumflex artery, as proposed by the American Heart Association model, we, in addition to Pereztol-Valdes et al. (3), found that this segment is more often supplied by the LAD. The diagnostic accuracy of midanterolateral involvement for a LAD stenosis/occlusion reached 80% in our study and 63% in the Pereztol-Valdes et al. (3) study. As stated by Dr. Danias, differences in methodologies and anatomical coronary variations may explain these disparities. Aepfelbacher et al. (2) included patients with either single or multivessel disease, with 42% of the cohort having previously undergone coronary revascularization. Pereztol-Valdes et al. (3) investigated patients with newly diagnosed single-vessel disease. The inclusion of patients with concomitant significant disease in the LAD and left circumflex territory might preclude appropriate registration in this particular segment.
The patient population used in our study included subjects who presented with an acute myocardial infarction to a single acute coronary occlusion. Additionally, the presence of previous myocardial scar in areas not corresponding and distinct to the infarct related artery was excluded. It should be also stressed that the use of cardiac magnetic resonance imaging allows the identification of the anterior and inferior right ventricular junction points, which in addition to the center of the left ventricular cavity, represent strong landmarks permitting a precise segmentation of the septum and left ventricular free wall. Further hybrid imaging studies that fuse the depiction of the coronary arteries as it courses on the left ventricular wall with functional imaging, like single-emission photon computed tomography/computed tomography, positron emission tomography/computed tomography, or cardiac magnetic resonance imaging angiography/perfusion, are warranted to clarify these disparities.
(Email: ed-wu{at}northwestern.edu).
 |
REFERENCES
|
|---|
- Ortiz-Pérez JT, Rodriguez J, Meyers SN, Lee DC, Davidson C, Wu E. Correspondence between the 17-segment model and coronary arterial anatomy using contrast-enhanced cardiac magnetic resonance imaging J Am Coll Cardiol Img 2008;1:282-293.[Abstract/Free Full Text]
- Aepfelbacher FC, Johnson RB, Schwartz JG, et al. Validation of a model of left ventricular segmentation for interpretation of SPET myocardial perfusion images Eur J Nucl Med 2001;28:1624-1629.[CrossRef][Web of Science][Medline]
- Pereztol-Valdes O, Candell-Riera J, Santana-Boado C, et al. Correspondence between left ventricular 17 myocardial segments and coronary arteries Eur Heart J 2005;26:2637-2643.[Abstract/Free Full Text]
- Setser RM, O'Donnell TP, Smedira NG, et al. Coregistered MR imaging myocardial viability maps and multi-detector row CT coronary angiography displays for surgical revascularization planning: initial experience Radiology 2005;237:465-473.[Abstract/Free Full Text]
Related Article
-
Concordance Between Actual and Expected Coronary Artery Distribution
- Peter G. Danias
J. Am. Coll. Cardiol. Img. 2008 1: 688.
[Full Text]
[PDF]
|
Top
REFERENCES