In 2007, a 72-year-old woman with a history of smoking, hypertension, and hyperlipidemia was referred to our department for preoperative evaluation before breast surgery. The patient had no cardiac symptoms. In 1997, however, she had undergone coronary artery bypass grafting with 2 internal mammary arteries for repair of a catheter-induced dissection of the left main coronary artery (LMCA).
Sixty-four–slice computed tomography was performed before the breast surgery with retrospective gating and electrocardiographic dose modulation. Images were reconstructed at mid-diastole of the cardiac cycle. Multiplanar reformation of the proximal left coronary system revealed the previous dissection, which extended from the mid-segment of the LMCA toward the bifurcation of the left anterior descending artery (LAD) and left circumflex artery (LCx) (Fig. 1A). No stenosis was identified in the LMCA. The LAD, LCx, and right coronary artery were also widely patent. A volume-rendered image of the heart (Fig. 1B) showed surgical clips from the previous bypass surgery, consistent with grafting of the left and right internal mammary arteries to the LAD and LCx, respectively. The bypass grafts were atretic, likely because of the unlimited flow in the native coronary arteries.
Fig. 1 A) Multiplanar reconstruction of the 64-slice computed tomography depicts the proximal left coronary system. The left main coronary artery (LMCA) branches out into 2 coronary arteries: the left anterior descending (LAD) and the left circumflex (LCx). The dissection flap extends from the mid LMCA toward the bifurcation of the LAD and the LCx, then continues down the proximal part of the LCx. B) This volume-rendered image of the heart shows the patent (contrast-filled) LAD and LCx. Surgical clips (white arrows) delineate the course of the left and right internal mammary artery grafts; the lack of contrast material indicates that the grafts are atretic. The 1st diagonal (D1) and the 1st obtuse marginal (OM1) arteries are also visible.
Comment
Catheter-induced dissection of a coronary artery is a rare but well-recognized complication of coronary angiography.1 This type of dissection can be life-threatening—especially in hemodynamically unstable patients. Documentation of coronary artery dissection (particularly of the LMCA2) by multislice computed tomography has also been reported, although rarely.3-6 Recent studies, however, have shown the accuracy of this imaging method for the diagnosis of coronary artery disease7 and for the evaluation of bypass grafts.8 Our case is unique in that 64-slice computed tomography accurately identified not only the previous LMCA dissection but also the atretic bypass grafts.
Footnotes
Address for reprints: Benjamin Y.C. Cheong, MD, Texas Heart Institute at St. Luke's Episcopal Hospital, 6720 Bertner Ave., MC 2–270, Houston, TX 77030
E-mail: bcheong@sleh.com
References
- 1.Awadalla H, Sabet S, El Sebaie A, Rosales O, Smalling R. Catheter-induced left main dissection incidence, predisposition and therapeutic strategies experience from two sides of the hemisphere. J Invasive Cardiol 2005;17(4):233–6. [PubMed]
- 2.Ando G, Saporito F, Cerrito M, Salamone I, Pandolfo A, Arrigo F, Oreto G. Imaging of left main coronary artery dissection with multislice computed tomography. Int J Cardiol 2007;115(3):e111–3. [DOI] [PubMed]
- 3.Dwyer N, Galligan L, Harle R. Spontaneous coronary artery dissection and associated CT coronary angiographic findings: a case report and review. Heart Lung Circ 2007;16(2):127–30. [DOI] [PubMed]
- 4.Manghat NE, Morgan-Hughes GJ, Roobottom CA. Spontaneous coronary artery dissection: appearance and follow-up on multi-detector row CT coronary angiography. Clin Radiol 2005;60(10):1120–5. [DOI] [PubMed]
- 5.Kantarci M, Ogul H, Bayraktutan U, Gundogdu F, Bayram E. Spontaneous coronary artery dissection: noninvasive diagnosis with multidetector CT angiography. J Vasc Interv Radiol 2007;18(5):687–8. [DOI] [PubMed]
- 6.Lubarsky L, Jelnin V, Roubin GS, Hecht HS. Spontaneous right coronary artery dissection: evaluation by 64-slice multidetector computed tomographic angiography. J Invasive Cardiol 2007;19(6):280–1. [PubMed]
- 7.Achenbach S. Computed tomography coronary angiography. J Am Coll Cardiol 2006;48(10):1919–28. [DOI] [PubMed]
- 8.Nieman K, Pattynama PM, Rensing BJ, Van Geuns RJ, De Feyter PJ. Evaluation of patients after coronary artery bypass surgery: CT angiographic assessment of grafts and coronary arteries. Radiology 2003;229(3):749–56. [DOI] [PubMed]