Secondary Logo

Journal Logo

Ascending Aortic Pseudoaneurysm: A Late Complication of Coronary Artery Bypass

Konia, Mojca, MD; Uppington, Jeffrey, MD; Moore, Peter, MD, PhD; Liu, Hong, MD

doi: 10.1213/ane.0b013e3181608bbd
Cardiovascular Anesthesiology: Echo Didactics & Rounds
Free
CME
Video 1
Video 2

From the Department of Anesthesiology and Pain Medicine, University of California, Davis, California.

This article has supplementary material on the Web site:www.anesthesia-analgesia.org

Accepted for publication October 26, 2007.

Address correspondence and reprint requests to Hong Liu, MD, Department of Anesthesiology and Pain Medicine, University of California Davis Health System, 4150 V St., Suite 1200, Sacramento, CA 95817. Address e-mail to hualiu@ucdavis.edu.

An 83-yr-old man, with a history of myocardial infarction and coronary artery bypass grafting surgery performed 21 yr ago, presented with increasing midsternal chest pain radiating to his back and shortness of breath. He was diagnosed with a non-ST-elevation myocardial infarction. Cardiac catheterization showed an occluded saphenous vein graft to the first diagonal branch and a mass attached to the ascending aorta with uncertain involvement of the saphenous vein graft. Magnetic resonance imaging (MRI) showed a pseudoaneurysm, measuring 4.6 × 12.5 cm2, which appeared to originate from the saphenous vein graft to the diagonal branch. The pseudoaneurysm had bloodflow into an approximately 5 × 2.4 cm2 oblong space that was surrounded by a spherical, heterogeneous, formed hematoma. The pseudoaneurysm extended superiorly to the level of the aortic arch and inferiorly to the level of the diaphragm. It significantly compressed the superior vena cava, right atrium (RA), and right ventricle (RV).

Surgery to excise the pseudoaneurysm was planned with right subclavian artery/femoral vein cardiopulmonary bypass and deep hypothermic circulatory arrest. Radial and pulmonary arterial catheters were placed for hemodynamic monitoring; no significant RV pressure increase was noticed (34/4 mm Hg). A thorough intraoperative transesophageal echocardiography (TEE) was performed to look for the characteristics of a pseudoaneurysm that include a thin-walled cavity and expansion during systole and collapse during diastole. The TEE showed a thin-walled cavity that was filled with a nonhomogeneous material and did not expand or collapse with systole and diastole. Color Doppler examination showed what appeared to be bloodflow in the cavity (Video clips 1 and 2; please see video clips available at www.anesthesia-analgesia.org), but this finding did not correlate with the location of bloodflow demonstrated previously by MRI and angiography. The TEE confirmed RA and RV compression with mild tricuspid regurgitation (Figs. 1, 2, and Video clip 1). The aortic valve (AV) appeared normal in both the mid-esophageal (ME) AV short and long axis views. The ascending aorta was also normal from the upper esophageal aortic arch long axis view, ME AV long axis view, ME ascending aortic long axis view, and the ME left ventricular (LV) long axis view.

Figure 1.

Figure 1.

Figure 2.

Figure 2.

A right anterior thoracotomy approach was used and, after cardiopulmonary bypass was established, the patient's temperature was decreased to 20°C. The pseudoaneurysm was excised and brown-colored fluid with necrotic material was evacuated. During careful inspection, two small holes were identified in the lateral wall of the ascending aorta located 1.5 cm above the aortic valve. The bleeding pressure from the two holes was very low and no communication with the saphenous vein graft was noted. Suture repair of the ascending aorta was made easier by a transient 2-min circulatory arrest. After resection of the pseudoaneurysm, the compression of the RA and RV were significantly relieved (Video clip 2). The descending aorta was then carefully examined by TEE and no additional pathology was found. The patient recovered uneventfully.

A pseudoaneurysm, also known as a false aneurysm, is an outpouching of a blood vessel caused by a defect in the two innermost layers (tunica intima and media) with continuity of the outermost layer (tunica adventitia). Alternatively, all three layers are damaged and the bleeding is contained by a blood clot or surrounding structures. Ascending aortic pseudoaneurysm is a rare complication of cardiac surgery, which is often caused by Staphylococcus epidermidis, Staphylococcus aurous or Propionibacterium acnes.1,2 Other etiologies include trauma, connective tissue disease, vasculitis, and prior aortic surgery. The differential diagnoses of pseudoaneurysm include mediastinal mass, mediastinal cyst, endocrine tissue, abscess, effusion, and vascular and cardiac structures. Pseudoaneurysms may occur as an early or late complication of surgery and have been described to occur as late as 18 yr after surgery.3 They most frequently occur at the site of a graft anastomoses, an aortotomy, or a cannulation.4 The repair can be safely performed with cardiopulmonary bypass and hypothermic circulatory arrest.1

In this case, a pseudoaneurysm was discovered 21 yr after the initial coronary artery bypass surgery. The bleeding site did not seem to be related to the areas exposed to surgical trauma during the initial surgery. Pathologic examination showed the necrotic contents of the pseudoaneurysm to be lung and pericardial tissues that might have contained the bleeding. Cultures of the necrotic tissue were positive for Propionibacterium acnes, a slow-growing, obligate anaerobic bacteria that has been reported to be associated with endocarditis.5

The use of intraoperative TEE confirmed the diagnosis from MRI and angiography and enabled a detailed examination of the pseudoaneurysm and its involvement with surrounding structures, including the superior vena cava, RA and RV compressions. TEE also provided us with continuous monitoring of hemodynamic changes of the LVE and right ventricular functions, monitoring of the LV regional wall motion abnormality during surgical manipulation, the post-repair examination of the aorta, and the confirmation that there was no apparent additional pathology.

Back to Top | Article Outline

REFERENCES

1. Dumont E, Carrier M, Cartier R, Pellerin MD, Poirier N, Bouchard D, Perrault LP. Repair of aortic false aneurysm using deep hypothermia and circulatory arrest. Ann Thora Surg 2004; 78:117–20
2. Tammelin A, Hambraeus A, Stahle E. Mediastinitis after cardiac surgery: improvement of bacteriological diagnosis by use of multiple tissue samples and strain typing. J Clin Micorbiol 2002;40:2936–41
3. Dhadwal AK, Abrol S, Zisbrod Z, Cunningham JN. Pseudoaneurysm of the ascending aorta following coronary artery bypass surgery. J Card Surg 2006;21:221–4
4. Sabri MN, Henry D, Wechsler AS, Di Sciascio G, Vetrovec GW. Late complications involving the ascending aorta after cardiac surgery: recognition and management. Am Heart J 1991; 121:1779–83
5. Hinestrosa F, Djukovic S, Bourbeau PP, Foltzer MA. Propionibacterium acnes as a cause of prosthetic valve aortic root abscess. J Clin Microbiol 2007;45:259–61
© 2008 International Anesthesia Research Society