Ann Thorac Surg 2008;86:1373-1375. doi:10.1016/j.athoracsur.2008.04.009
© 2008 The Society of Thoracic Surgeons
Case Reports
Flow Impeding Fungal Thrombus in the Ascending Aorta
Jiapeng Huang, MD, PhDa,b,*,
Michael J. Bouvette, MDa,b,
Yousef Hagi, MDa,b,
Sujata Subramanian, MDc,
Jing Zhou, MSNA, CRNAb,
Erle H. Austin, III, MDc
a Department of Anesthesia, Jewish Hospital & St. Mary's Healthcare, University of Louisville, Louisville, Kentucky
b Department of Anesthesiology and Perioperative Medicine, University of Louisville, Louisville, Kentucky
c Department of Surgery, University of Louisville, Louisville, Kentucky
Accepted for publication April 3, 2008.
* Address correspondence to Dr Huang, 200 Abraham Flexner Way, Louisville, KY 40202 (Email: jiapenghuang{at}yahoo.com).
 |
Abstract
|
|---|
Mycotic endoaortitis is a rarely occurring infectious entity with an extremely high mortality rate. We report an uncommon case of Phialemonium endoaortits with its management. This large fungal thrombus in the ascending aorta caused significant impediment to the blood flow.
|
Introduction
|
|---|
Mycotic cardiovascular disease is a rarely occurring infectious entity that usually follows surgeries involving cardiopulmonary bypass. Patients who are immunocompromised or have had long-term antibiotic treatment are most susceptible. Cardiovascular fungal infections usually present clinically as endocarditis. Mycotic involvement of the ascending aorta in the absence of endocarditis is even rarer and is usually lethal [1]. The most common caused species are the Aspergillus fungi.
Computed tomography, magnetic resonance imaging, and echocardiography have all been used to diagnose fungal endoaortitis. Echocardiography, particularly transesophageal echocardiography (TEE) provides the ability to clearly evaluate all of the heart valves and chambers, as well as the aorta, except for zones 4 and 5, due to interference from the right main bronchus. Early diagnosis and treatment of fungal endoaortitis is crucial because of its extremely high mortality rate.
We report a case of an unusual fungal thrombus in the ascending aorta, caused by the very exceptional Phialemonium species, with its subsequent medical and surgical management aided by TEE.
A 21-year-old woman presented to the emergency room with pain and numbness in both lower extremities. She did not have any known drug allergies. Her medical history was significant for congenital supravalvular aortic stenosis and a patent foramen ovale. Five weeks prior to this admission, her aortic stenosis was repaired with a pericardial patch and her patent foramen ovale was also closed. During that surgery, her aorta and coronary ostia were found to have significant atherosclerotic changes. On physical examination, her blood pressure was 100/52, her pulse was 114, her respiratory rate was 20, her body temperature was 98.4, and her oxygen saturation was 100%. Her lungs were clear and a 2/6 systolic murmur was heard along the sternum. Sensory deficits and diminished pulses were present in both legs.
A computed tomographic angiogram was performed, which showed a left common femoral arterial embolus, as well as a large thrombus in the ascending aorta. She underwent a successful left femoral thrombectomy and was then started on heparin. During the next 2 days, a right femoral and left renal arterial emboli developed for which she subsequently required a right femoral thrombectomy.
The combination of multiple systemic emboli and a large thrombus in the ascending aorta prompted the decision to surgically remove the thrombus from the ascending aorta. General anesthesia was induced with standard techniques. Intraoperative TEE revealed a homogenous, mobile mass that measured 1.68 cm x 1.79 cm in the ascending aorta. This mass extended from the level of the sinotubular junction proximally to the level of the main pulmonary artery crossover distally (Figs 1A and 1B). The ascending aortic wall appeared highly echogenic, reflecting heavy calcification, significant scarring, or the pericardial patch itself from her previous surgery. The diameter of the ascending aorta measured 2.04 cm with the mass occupying approximately 80% of the lumen. The mass moved forward during systole and swayed back toward the heart in diastole. Color Doppler flow demonstrated flow turbulence around the mass in the ascending aorta (Fig 1C). Continuous wave Doppler showed an interesting triple envelope pattern (Fig 2A). The first and second envelops represented flow across the left ventricular outflow tract and the aortic valve, respectively. The third envelop (with the highest velocity of about 3.8 m/s) was presumed to be the flow across the mass. This demonstrated a newly formed supravalvular stenosis at the level of the fungal thrombus. Mild aortic regurgitation was also noted. No residual patent foramen ovale was found.
View larger version (26K):
[in this window]
[in a new window]
|
Fig 1. (A) A midesophageal ascending aorta short-axis view showing a large, homogenous mass in the ascending aorta. (B) A midesophageal long-axis view demonstrating a highly echocardiographic dense ascending aortic wall with a large mass near the sinotubular junction. (C) Color Doppler flow of the ascending aorta revealed flow turbulence in the aorta.
|
|
View larger version (56K):
[in this window]
[in a new window]
|
Fig 2. (A) Preoperative continuous flow Doppler with a triple envelope pattern representing left ventricular outflow tract, aortic valve, and thrombus level flow velocities. (B) Postoperative continuous flow Doppler revealed the normal double envelope pattern representing left ventricular outflow tract and aortic valve levels flow velocities.
|
|
A standard reoperation sternotomy was performed. Femoral aortic cannulation and right atrial venous cannulation were used for cardiopulmonary bypass and deep hypothermic circulatory arrest to provide minimal aortic manipulation and to avoid dislodging the mass. The thrombus was found to extend from just below the sinotubular junction to halfway up the ascending aorta, but not into the arch. It was loosely attached to right side of the aorta with some attachment to the area that was patched. The patch was not removed or replaced as it did not seem to be the primary source of the thrombus, and we did not think this was an infection at the time of surgery. She was rewarmed and weaned off cardiopulmonary bypass without any pharmacologic support. Postoperative TEE showed an ascending aorta without any visible mass. Continuous wave Doppler measurements at that time converted back to the classic double envelope pattern with similar left ventricular outflow tract and aortic flow velocities as the preoperative assessment. This confirmed that the third envelope that was preoperatively detected was in fact representative of the flow across the mass in the ascending aorta (Fig 2B). This also reassured us that the source of supravalvular stenosis has been removed.
The postoperative course of the patient was complicated by several peripheral thrombi. All of her thrombus samples demonstrated focal acute inflammation without any fungal elements. A culture from one of the samples grew a fungus, which was identified as the Phialemonium species. Amphetericin B and voriconazole were started to treat her fungal infection, according to the sensitivity studies. Aspirin, clopidogrel, and warfarin were initiated for anticoagulation due to the recurrent nature of her embolism. She was discharged home 1 month after her surgery.
|
Comment
|
|---|
Fungal endoaortitis usually occurs after aortic surgeries. It is believed that airborne spores seed the damaged aortic wall and then grow. However, systemic fungal infections without previous aortic surgery have also been reported to cause fungal endoaortitis. Most aortic fungal infections develop an aortic aneurysm due to disintegration and weakening of the aortic wall by the inflammatory process [2]. Our patient did not have an aortic aneurysm, probably because of the resistant and durable nature of the pericardial patch. Endocarditis rarely develops in patients with fungal endoaortitis, because the infection source is located at the supracoronary artery level [3]. This makes the diagnosis of endoaortitis alone delayed and difficult. The TEE can be used to evaluate the location and size of fungal thrombus, with the benefits of evaluating the heart, simultaneously.
Phialemonium species have emerged as new opportunistic fungal pathogens of humans, mostly in immunosuppressed and hospitalized patients [4]. Ophthalmic, pulmonary, and cardiac infections by the Phialemonium species have all been reported in the literature. We believe that this is the first report of Phialemonium endoaortits. Our patient received standard preoperative cephalosporin prophylaxis for all her surgeries. Risk factors for our patient included the aortic surgery itself, which directly damaged the aortic wall. Heavy calcification and atheromas in her aorta might have also played an important role in the initiation of thrombus formation and fungal adherence. The cause of her subsequent emboli after the successful removal of the ascending aortic thrombus is unknown, as they were delayed in appearance, and antifungal therapy was not started until several weeks after her aortic surgery. This delay in treatment was due to the slow growth of this specific organism.
Treatment of fungal endoaortitis includes aggressive medical and surgical approaches as illustrated in this case. With a very high mortality and morbidity, fungal endoaortitis requires prompt diagnosis and treatment. A strong clinical suspicion should be exercised in any patients with negative blood cultures presenting with recurrent thrombi after cardiac or aortic surgery. The TEE serves as an excellent tool to provide quick and accurate information about the aorta at the bedside, which is an obvious advantage, considering that those patients are usually critically ill.
|
References
|
|---|
- Rose HD, Utz JP. Mycotic aneurysm of the thoracic aorta caused by Aspergillus fumigates
Chest 1976;70:81-84.[Medline]
- Grothues F, Welte T, Grote HJ, Rossner A, Klein HU. Floating aortic thrombus in systemic aspergillosis and detection by transesophageal echocardiography Crit Care Med 2002;30:2355-2358.[Medline]
- Sanchez-Recalde A, Mate I, Merino JL, Simon RS, Sobrino JA.
Aspergillus aortitis after cardiac surgery JACC 2003;41:152-156.[Abstract/Free Full Text]
- Proia LA, Kammeyer PL, Ortiz J, et al. Phialemonium: an emerging mold pathogen that caused 4 cases of hemodialysis-associated endovascular infection Clin Infect Dis 2004;39:373-379.[Medline]
This article has been cited by other articles:
|
|
|
|
 
L. R. Leon Jr and J. L. Mills Sr
Diagnosis and Management of Aortic Mycotic Aneurysms
Vascular and Endovascular Surgery,
January 1, 2010;
44(1):
5 - 13.
[Abstract]
[PDF]
|
|
|
Top
Abstract
Introduction
