Left Main Coronary Artery Compression Syndrome Evaluation With 64-Slice Cardiac Multidetector Computed Tomography Jonathan D. Dodd, MD, MSc, MRCPI, FFR(RCSI); Andrew Maree, MD; Igor Palacios, MD; Michael M. de Moor, MD; Eline A.Q. Mooyaart, MS; Michael D. Shapiro, MD; Maros Ferencik, MD; Thomas Brady, MD; Suhny Abbara, MD; Ricardo C. Cury, MD; Udo Hoffmann, MD, MPH A 28-year-old man presented to the emergency depart- ment with progressive shortness of breath complicated by large hemoptysis. At 3 months of age, he had been diagnosed with a “hole in his heart” in the Ukraine and had undergone 3 coronary catheterizations (2 in Russia, 1 in India; results unavailable). His parents had declined options for treatment. After stabilization in the emergency depart- ment, he was transferred to coronary care, where echocardi- ography demonstrated a persistent ductus arteriosus (PDA) measuring 0.92.0 cm with a right-to-left shunt consistent with Eisenmenger syndrome. Left ventricular function was severely impaired (ejection fraction=21%). Cardiac 64-slice multidetector computed tomography (MDCT) was undertaken to provide optimal depiction of the PDA and main pulmonary artery (PA) and confirmed a widely patent PDA measuring 2.0 cm in largest diameter (Figure 1A). Functional MDCT cine multiphase reconstruc- tions of the PDA revealed a bidirectional shunt (Movie I). Main, left, and right PAs were markedly enlarged (Figure 1B). Coronary MDCT evaluation demonstrated severe left main coronary artery (LM) compression 90% between the aortic sinus and the enlarged PA (Figure 1C). Additionally, coronary MDCT demonstrated a downward angulation of the LM with the left sinus of Valsalva of 11° (Figure 1D). Functional MDCT cine multiphase reconstructions demon- strated dynamic compression of the LM between the aortic sinus and the PA during systole (Movie II and III) and confirmed severe global left and right ventricular dysfunction (Movie IV). Noncardiac findings included pulmonary hem- orrhage and pulmonary parenchymal peripheral vascular pruning that were consistent with severe pulmonary hyper- tension and Eisenmenger syndrome (Figure 1E). Coronary angiography confirmed LM stenosis (Figure 2; Movie V), and hemodynamic evaluation revealed a Qp/Qs of 1.05. Three days after catheterization, the patient suffered a cardiac arrest and underwent percutaneous transcatheter in- tervention with stent placement across the LM. The patient declined heart–lung transplantation and was discharged in stable condition. The patient remains event free at 4-month follow-up. Left coronary artery compression syndrome was first described in 1957 and is characterized by compression of the LM between the aorta and an enlarged main PA. 1 It is usually seen with a congenital cardiac defect, most commonly an atrial septal defect, ventricular septal defect, or tetralogy of Fallot. 2 The association between an isolated PDA and left coronary artery compression is rare. 3 Both the degree of LM compression and its angle with the left sinus of Valsalva 30° are thought to increase the likelihood of significant myocardial ischemia. A main PA/aorta diameter ratio 2 is considered an additional risk factor. Cardiac 64-slice MDCT provides a noninvasive method for evaluating the degree of dynamic LM compression throughout the cardiac cycle, angulation of the LM relative to the left sinus of Valsalva, evaluation of left and right ventricular function, and depiction of pulmonary pathology, making it a valuable investigation in the workup of patients suspected of left coronary artery compression. Disclosures None. References 1. Corday E, Gold H, Kaplan L. Coronary artery compression; an expla- nation for the cause of coronary insufficiency in pulmonary hypertension. Trans Am Coll Cardiol. 1957;7:93–103. 2. Kajita LJ, Martinez EE, Ambrose JA, Lemos PA, Esteves A, Nogueira da Gama M, Jatene AD, Ramires JA. Extrinsic compression of the left main coronary artery by a dilated pulmonary artery: clinical, angiographic, and hemodynamic determinants. Catheter Cardiovasc Interv. 2001;52:49 –54. 3. Higgins JC, O’Brien JK, Battle RW, Tischler MD. Left main coronary artery compression in patent ductus arteriosus. Am Heart J. 1993;125: 236 –239. Departments of Radiology and Cardiac CT/MRI/PET Program (J.D.D., E.A.Q.M., M.D.S., M.F., T.B., S.A., R.C.C., U.H.) and Cardiology (A.M., I.P., M.M.d.M.), Massachusetts General Hospital and Harvard Medical School, Boston, Mass. The online-only Data Supplement, consisting of movies, is available with this article at http://circ.ahajournals.org/cgi/content/full/115/1/e7/DC1. Correspondence to Jonathan D. Dodd, MD, MSc, MRCPI, FFR(RCSI), Department of Radiology, St Vincent’s University Hospital, Elm Park, Dublin 4, Ireland. E-mail j.dodd@st-vincents.ie (Circulation. 2007;115:e7-e8.) © 2007 American Heart Association, Inc. Circulation is available at http://www.circulationaha.org DOI: 10.1161/CIRCULATIONAHA.106.645622 e7 Images in Cardiovascular Medicine by guest on January 17, 2016 http://circ.ahajournals.org/ Downloaded from