Mycotic Aortocoronary SaphenousVein Graft Aneurysm PresentingWith Unstable Angina PectorisGlenn A. Hirsch, MD, Peter V. Johnston, MD,John V. Conte, Jr, MD, and Stephen C. Achuff, MD

Division of Cardiology and Department of Cardiac Surgery,The Johns Hopkins Hospital, Baltimore, and National Heart,Lung, and Blood Institute, National Institutes of Health,Bethesda, Maryland

We report the case of a 60-year-old man with a history ofcoronary bypass surgery 20 years prior who had a fever,chest pain, and a mediastinal mass develop after acomplicated postoperative course of abdominal aorticaneurysm resection. A mycotic aneurysm of the saphe-nous vein graft to his left anterior descending coronaryartery was diagnosed based on blood culture results andvisualization of the aneurysm before resection. A sum-mary of the saphenous vein graft aneurysm and pseudo-aneurysm cause, diagnosis, and management is detailed.

(Ann Thorac Surg 2004;78:1456–8)© 2004 by The Society of Thoracic Surgeons

Aneurysms and pseudoaneurysms of saphenous veingrafts (SVGs) to the coronary arteries are rare, and

only four mycotic SVG aneurysms have been previouslyreported [1–4]. We present the case of a mycotic SVGaneurysm presenting as an unstable angina after resec-tion of an abdominal aortic aneurysm with a complicatedpostoperative course. Recognition, evaluation, and man-agement of this condition are discussed.

A 60-year-old man with a history of diabetes mellitus,hyperlipidemia, smoking, and four-vessel coronary ar-tery bypass (CAB) 20 years previously underwent emer-gent repair of an abdominal aortic aneurysm at a refer-ring institution. His postoperative course wascomplicated by multiple episodes of bacteremia withEnterococcus faecalis and Staphylococcus aureus, sepsis, andacute respiratory distress syndrome. In addition, thepatient had hemorrhagic pancreatitis and ischemic colitisdevelop, which required a distal pancreatectomy, sple-nectomy, and partial bowel resection. He returned to theoperating room for lysis of adhesions to relieve a post-operative small bowel obstruction. Two months after hisinitial abdominal aortic aneurysm repair, he was trans-ferred to our hospital for further management. On arrivalhe remained ventilator dependent and critically ill withmultiple abdominal abscesses and an entero-cutaneousfistula. Over the following month his condition slowlyimproved with antibiotics, percutaneous drainage of his

abdominal abscesses, and intense nutritional support. Hewas subsequently weaned from the ventilator. Despitemore than 1 month of antibiotic therapy, the patientremained febrile with temperatures exceeding 38°C.Nevertheless he remained hemodynamically stable andwas transferred out of the intensive care unit.

One day later, the patient had chest pain develop whilemoving from his bed to the chair. It was the first time hehad experienced anginal symptoms since his CAB 20years previously. Sublingual nitroglycerin was given tothe patient, which resolved his pain and electrocardio-graphic changes. Serum cardiac enzyme levels were nor-mal. Echocardiography revealed no regional wall motionabnormality, but a large anterior mediastinal mass com-pressing the right ventricle was present (Fig 1). To evaluatethis mass, computed tomography of the thorax was per-formed that revealed a 6.0 � 3.0 cm calcified aneurysm ofthe SVG to the left anterior descending artery (LAD). Bloodflow was maintained through a narrowed but patent graftlumen (Fig 2). Magnetic resonance imaging of the thoraxrevealed the presence of layered intraluminal thrombuswithin the aneurysm and a patent graft lumen (Fig 3).

The cardiac catheterization performed the previousyear after a positive stress test was reviewed. It demon-strated an ectatic SVG to the LAD without evidence ofaneurysm or stenosis. The other three vein grafts were100% occluded, as were the patient’s native LAD andright coronary arteries. The left circumflex remainedlargely disease free and appeared to provide much of thecollateral blood flow to the right coronary artery. Thesetting of multiple episodes of bacteremia, persistentfevers, unstable angina, and the new SVG aneurysm wasconcern for a mycotic SVG aneurysm. In anticipation ofsurgical therapy, a repeat cardiac catheterization demon-strated no change from the one done previously, exceptfor the aneurysmal SVG to the LAD (Fig 4). The aneu-rysm appeared to be filled with thrombus. Despite ex-tensive coronary artery disease, good target vessels forbypass grafting were present in the distal regions of theLAD and right coronary artery.

The patient was subsequently taken to the operatingroom for resection of a presumed mycotic SVG aneurysmand repeat CAB. After a standard median sternotomyapproach, a 6.0 � 4.0 cm aneurysm of the SVG graft to theLAD was noted to be compressing the right ventricle. Theleft internal mammary artery was damaged during thepatient’s first CAB and was unavailable for use; thus twoSVGs were placed with one to the LAD and the other tothe posterior descending artery. The aneurysmal SVGgraft was ligated proximally and distally, and retrogradeblood cardioplegia was performed to wash out any ma-terial remaining in the open artery. Upon incision of theaneurysmal SVG, intraluminal thrombus and approxi-mately 100 mL of suppurative material were revealed.This SVG was then resected. Histopathologic examina-tion revealed aneurysm with thrombosis and focal calci-fication. Gram stain, fungal stain, and cultures of thepurulent material were all negative. Postoperatively, thepatient was maintained on broad-spectrum antibioticcoverage, and he slowly recovered. Six months after his

Accepted for publication July 10, 2003.

Address reprint requests to Dr Hirsch, NHLBI/NIH, 10 Center Dr,MSC-1061, Bldg 10, Room B1D-416, Bethesda, MD 20892-1061; e-mail:ghirsch@jhmi.edu.

1456 CASE REPORT HIRSCH ET AL Ann Thorac SurgMYCOTIC SAPHENOUS VEIN GRAFT ANEURYSM 2004;78:1456–8

© 2004 by The Society of Thoracic Surgeons 0003-4975/04/$30.00Published by Elsevier Inc doi:10.1016/S0003-4975(03)01516-9

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original abdominal aortic aneurysm repair, the patientwas discharged from the hospital.

CommentAneurysms and pseudoaneurysms of coronary artery SVGsare rare, having been reported in the literature less than 80times in the past 30 years. Mycotic or infected coronaryartery bypass graft aneurysms are only a small fraction ofthe reported cases, with only 4 patients who were previ-ously documented [1–4]. In all of these patients, the mycoticaneurysms developed within the first postoperative yearand in 2 of 4 patients, the aneurysms developed within theimmediate postoperative period. Of these 4 patients, 3 hadpostoperative mediastinitis or sternal wound infection, orboth. All of these patients underwent repeat sternotomies,and in 2 patients it was fatal.

Our case is unusual because the mycotic aneurysmdeveloped many years after graft placement and because

it occurred outside the setting of postoperative medias-tinitis or sternal wound infection. The patient in thepresent case report had an aneurysm that likely devel-oped after multiple bacteremic episodes that complicatedthe postoperative course of his abdominal aortic aneu-rysm resection. Despite the abundant amount of puru-lent fluid found intraoperatively, we were unable toidentify a causative organism in this case, probably from

Fig 1. (A) Echocardiogram showing extrinsic compression of rightventricle (dashed arrow) by mass (solid arrow) on parasternallong axis view. (B) The arrow points to mass abutting the right ven-tricle and anterior wall of the left ventricle on short-axis view. (LV� left ventricle.)

Fig 2. Computed tomographic scan of the thorax reveals a dilated,calcified saphenous vein graft (arrow) in the anterior mediastinum.

Fig 3. Magnetic resonance image of the thorax demonstrating aneu-rysmal saphenous vein graft with intraluminal layered thrombus(solid arrow) and a patent lumen (dashed arrow).

Fig 4. Coronary angiogram of the saphenous vein graft to the leftanterior descending artery. The distal portion of the aneurysmal veingraft (solid arrow) with intraluminal thrombus inserts into the dis-tal left anterior descending artery (dashed arrow).

1457Ann Thorac Surg CASE REPORT HIRSCH ET AL2004;78:1456–8 MYCOTIC SAPHENOUS VEIN GRAFT ANEURYSM

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sterilization of the aneurysm fluid by a prolonged courseof broad-spectrum antibiotics. Of the 4 previously re-ported patients, 3 of the causative organisms were Staph-ylococcus aureus and Aspergillus was the isolated cause inthe other patient [1–4].

Typically SVG aneurysms present with ischemic symp-toms secondary to graft occlusion or distal embolizationfrom intraluminal thrombus, or as asymptomatic chestmasses detected during chest imaging. As described byLupetin and colleagues [5], the triad of chest pain, medi-astinal mass, and previous bypass surgery should raiseconcern of an SVG aneurysm. The most common graftinvolved is the SVG to the LAD. This is importantbecause aneurysms of this graft are usually not seen onstandard chest roentgenograms, whereas SVGs to theRCA or obtuse marginal branches may often be seen.

True aneurysms and pseudoaneurysms of SVGs occurwith the same frequency, but they are pathologically differ-ent. True aneurysms typically are fusiform and involve thebody of the graft and also commonly result from graftarteriosclerosis. Pseudoaneurysms, in contrast, are saccular,they usually present at the anastomotic site, and they areoften related to technical issues [6].

In a review of 50 cases of SVG aneurysm by Kalimi andcolleagues [6], the mean length of time post-CAB aneu-rysms were diagnosed was 10 years after surgery (range, 7days to 21 years). As SVGs age, they become more suscep-tible to have aneurysms develop secondary to acceleratedarteriosclerosis, and the inability of the thin venous wall toprevent dilatation. Our case, although extremely rare, illus-trates that patients with previous CAB and bacteremia areat risk for mycotic aneurysm formation.

Once an SVG aneurysm is detected, computed tomog-raphy or magnetic resonance imaging of the chest shouldbe performed to determine patency of the graft lumen, aswell as the precise location of the graft within themediastinum to guide the surgical approach. Beforeoperation, a diagnostic cardiac catheterization shouldalso be performed to evaluate potential distal targets forrevascularization. In the review of 50 SVG aneurysms byKalimi and colleagues [6], 31 patients underwent surgicalligation of the SVG aneurysm. Of these, 29 patients hadsimultaneous revascularizations of the affected vessel.The 2 patients who did not suffered large anterior wallmyocardial infarctions postoperatively indicative of theimportance of simultaneous revascularization in this set-ting. Embolization using coils placed percutaneously isanother therapeutic option; however, no simultaneousrevascularization occurs during this procedure. Kalimiand colleagues [6] suggest embolization should be re-served for patients deemed too high risk for repeat CAB.

This article describes a rare case of a mycotic SVGaneurysm that developed in a patient more than 20 yearsafter CAB surgery in the setting of multiple episodes ofbacteremia. Management of SVG aneurysms (mycotic orotherwise) depend on recognition of the disease, subse-quent evaluation with computed tomography or magneticresonance imaging of the chest to delineate the location ofthe aneurysm and patency of the graft lumen. This shouldbe followed by cardiac catheterization to locate target areas

for revascularization. The appropriate timing of surgery inpatients with an SVG aneurysm is not known. However, wewould advocate urgent surgical revascularization of symp-tomatic or suspected mycotic aneurysms. A more conser-vative, observational approach for asymptomatic patients isreasonable for SVG aneurysms less than 1 cm in diameterand with brisk graft flow. The observational strategy couldbe performed noninvasively by using either magnetic res-onance imaging, computed tomography or angiography.For those patients with SVG aneurysms greater than 1 cmin diameter or with diminished graft flow, prompt surgicalrevascularization would be recommended. Ligation or re-section of SVG aneurysms with simultaneous revascular-ization appears to be the optimal therapy, but intravascularembolization of the graft with coils may be an option forhigh-risk patients.

References1. Whiting RB, Barner HB, Leone P, Westura EE. Aspergilloma:

an unusual cause of late failure of aortocoronary bypass graft.Chest 1973;63:1030–3.

2. Douglas BP, Bulkley BH, Hutchins GM. Infected saphenousvein coronary artery bypass graft with mycotic aneurysm:fatal dehiscence of the proximal anastomosis. Chest 1979;75:76–7.

3. Page RD, Dixon GR, Fabri BM. Early rupture of a saphenousvein graft. Eur J Cardio-Thorac 1991;5:663–4.

4. Smith JA, Goldstein J. Saphenous vein graft pseudoaneurysmformation after postoperative mediastinitis. Ann Thorac Surg1992;54:766–8.

5. Lupetin AR, Gabriele FJ, Kramer CM, Reichek N. Magneticresonance imaging diagnosis of an aortocoronary saphenousvein graft aneurysm. Cardiovasc Intervent Radiol 1993;18:330–2.

6. Kalimi R, Palazzo RS, Graver LM. Giant aneurysm of saphe-nous vein graft to coronary artery compressing the rightatrium. Ann Thorac Surg 1999;68:1433–7.

Selective Arterialization of theCoronary Venous SystemJ. Rafael Sadaba, FRCS, andUnnikrishnan R. Nair, FRCS

Department of Cardiothoracic Surgery, Yorkshire HeartCentre, Leeds General Infirmary, Leeds, United Kingdom

The idea of myocardial revascularization by means ofgrafting the coronary venous system is more than acentury old; in cases of diffuse coronary artery disease,this may represent a valid therapeutic option. We presenta challenging case in which a patient with an aberrantleft coronary system and unstable angina underwent thistype of procedure with good clinical results.

(Ann Thorac Surg 2004;78:1458–60)© 2004 by The Society of Thoracic Surgeons

Accepted for publication July 10, 2003.

Address reprint requests to Dr Nair, Department of CardiothoracicSurgery, Leeds General Infirmary, Great George St, Leeds LS1 3EX, UK;e-mail: unnikrishnan.nair@leedsth.nhs.uk.

1458 CASE REPORT SABADA AND NAIR Ann Thorac SurgARTERIALIZATION OF CORONARY VEIN 2004;78:1458–60

© 2004 by The Society of Thoracic Surgeons 0003-4975/04/$30.00Published by Elsevier Inc doi:10.1016/S0003-4975(03)01654-0

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