Successful Emergent Endovascular Repair of a Ruptured Mycotic Thoracic Aortic Aneurysm

Treatment of a descending thoracic mycotic aneurysm secondary to disseminated aspergillosis infection with thoracic endovascular aortic repair

Mycotic aortic aneurysms are a rare and potentially fatal aortic pathology. Advancements in vascular technology have allowed endovascular repair to be a durable and less invasive option for the treatment of mycotic aortic aneurysms. We have presented the case of a 51-year-old man with a mycotic aneurysm of the descending thoracic aorta secondary to chronic, disseminated aspergillosis infection after liver transplantation. The aneurysm was successfully treated with thoracic aortic stent graft deployment. No perioperative complications occurred, and follow-up computed tomography angiography showed no signs of an endoleak. The patient will continue with lifelong antifungal therapy and close follow-up with vascular surgery.

Mycotic aneurysm of the distal thoracic aorta after botulinum toxin injection for esophageal dysmotility

Endoscopic injection of botulinum toxin is a common method to treat esophageal dysmotility and achalasia. Patients undergoing this procedure who subsequently present with abdominal or back pain and constitutional symptoms should be evaluated for possible complications of the procedure, including occult esophageal perforation, mediastinitis, and mycotic aneurysm of the thoracic aorta. The case described herein illustrates the importance of serial imaging in a patient with persistent symptoms after botulinum toxin injection to identify and to treat occult aortic inoculation leading to mycotic aneurysm before sepsis and aortic rupture ensue with their attendant morbidity and mortality risks.

Methicillin-resistant Staphylococcus aureus portends a poor prognosis after endovascular repair of mycotic aortic aneurysms and aortic graft infections

OBJECTIVE

Mycotic aortic aneurysms and aortic graft infections (aortic infections [AIs]) are rare but highly morbid conditions. Open surgical repair is the "gold standard" treatment, but endovascular repair (EVR) is increasingly being used in the management of AI because of the lower operative morbidity. Multiple organisms are associated with AI, and bacteriology may be an important indication of mortality. We describe the bacteriology and associated outcomes of a group of patients treated with an EVR-first approach for AI.

METHODS

All patients who underwent EVR for native aortic or aortic graft infections between 2005 and 2016 were retrospectively reviewed. Primary end points were 30-day mortality and overall mortality. The primary exposure variable was bacteria species. Logistic regression analysis was used to determine association with mortality. Kaplan-Meier survival analysis was used to estimate survival.

RESULTS

A total of 2038 EVRs were performed in 1989 unique and consecutive patients. Of those, 27 patients had undergone EVR for AI. Thirteen presented ruptured (48%). Eighteen (67%) were hemodynamically unstable. Ten had a gastrointestinal bleed (37%), whereas others presented with abdominal pain (33%), fever (22%), chest or back pain (18.5%), and hemothorax (3.7%). Twenty patients had a positive blood culture (74%), with the most common organism being methicillin-resistant Staphylococcus aureus (MRSA) isolated in 37% (10). Other organisms were Escherichia coli (3), Staphylococcus epidermidis (2), Streptococcus (2), Enterococcus faecalis (1), vancomycin-resistant Enterococcus (1), and Klebsiella (1). Thirteen patients had 4 to 6 weeks of postoperative antibiotic therapy, six of whom died after therapy. Fourteen were prescribed lifelong therapy; 10 died while receiving antibiotics. On univariate analysis for mortality, smoking history (P = .061) and aerodigestive bleeding on presentation (P = .109) approached significance, whereas MRSA infection (P = .001) was strongly associated with increased mortality. On multivariate analysis, MRSA remained a strong, independent predictor of mortality (adjusted odds ratio, 93.2; 95% confidence interval, 1.9-4643; P = .023). Overall 30-day mortality was 11%, all MRSA positive. At mean follow-up of 17.4 ± 28 months, overall mortality was 59%. Overall survival at 1 year, 3 years, and 5 years was 49%, 31%, and 23%. Kaplan-Meier survival analysis demonstrated that MRSA-positive patients had a significantly lower survival compared with other pathogens (1-year, 20% vs 71%; 5-year, 0% vs 44%; P = .0009).

CONCLUSIONS

In our series of AI, the most commonly isolated organism was MRSA. MRSA is highly virulent and is associated with increased mortality compared with all other organisms, regardless of treatment. Given our results, EVR for MRSA-positive AI was not a durable treatment option.

Infected aneurysm of the thoracic aorta probably caused by Bacillus cereus: a case report

BACKGROUND

An infected aneurysm of the thoracic aorta is a rare clinical condition with significant morbidity and mortality. Patients with fast-growing aortic aneurysms show a high incidence of rupture. Gram-positive organisms, such as the Staphylococcus and Enterococcus species, are the most common cause of infection.

CASE PRESENTATION

A 91-year-old man presented at our facility with high grade fever and tachypnea, which he had experienced for the previous two days. He had a history of end-stage renal disease and had been undergoing regular chest computed tomography (CT) follow-up for a left lower lung nodule. CT imaging with intravenous contrast media showed a thoracic aortic aneurysm with hemothorax. Rupture of the aneurysm was suspected. CT imaging performed a year ago showed a normal aorta. Blood samples showed a Bacillus cereus infection. The patient was successfully treated for a mycotic aortic aneurysm secondary to Bacillus cereus bacteremia.

CONCLUSIONS

Here, we report a rare of an infected aneurysm of the thoracic aorta probably caused by Bacillus cereus. Although infected aneurysms have been described well before, an aneurysm infected with Bacillus cereus is rare. Bacillus cereus, a gram-positive spore-building bacterium, can produce biofilms, which attach to catheters. It has recently emerged as a new organism that can cause serious infection.

Optimization of rifampin coating on covered Dacron endovascular stent grafts for infected aortic aneurysms

OBJECTIVE

In the treatment of an infected aorta, open repair and replacement with a rifampin-impregnated Dacron vascular graft decrease the risk of prosthetic graft infections, with several protocols available in the literature. We hypothesize that the same holds true for endovascular aneurysm repair, and after studying and optimizing rifampin solution concentration and incubation period to maximize the coating process of rifampin on Dacron endovascular stent grafts (ESGs), we propose a rapid real-time perioperative protocol.

METHODS

Several prepared rifampin solutions, including a negative control solution, were used to coat multiple triplicate sets of Dacron endovascular aortic stent grafts at different but set incubation periods. Rifampin elution from the grafts was studied by spectroscopic analysis. Once an optimized solution concentration and incubation time were determined, the elution of rifampin over time from the graft and the graft's surface characteristics were studied by ultraviolet-visible spectroscopy and atomic force microscopy.

RESULTS

All coated ESGs with any concentration of prepared rifampin solution, regardless of incubation time, immediately demonstrated a visible bright orange discoloration and subsequently after elution procedures returned to the original noncolored state. At the 25-minute incubation time (standard flush), there was no statistical difference in the amount of rifampin coated to the ESGs with 10-mg/mL, 30-mg/mL, and 60-mg/mL solutions (0.06 ± 0.01, 0.07 ± 0.05, and 0.044 ± 0.01, respectively; P > .05). This was also true for a 10-minute incubation time (express flush) of 10-mg/mL and 60-mg/mL rifampin solution concentrations (0.04 ± 0.007 and 0.066 ± 0.014, respectively; P = .22). The elution-over-time of coated rifampin ESG, although not statistically significant, did seem to plateau and to reach a steady state by 50 hours and was confirmed by surface characteristics using atomic force microscopy.

CONCLUSIONS

Having studied two variables of rifampin coating techniques to Dacron ESGs, the authors propose a rapid real-time perioperative coating protocol by using a 10-mg/mL rifampin solution for a 10-minute incubation period. As rifampin loosely binds to Dacron ESGs by weak intermolecular forces, a rifampin-coated ESG would need to be inserted in a timely fashion to treat the diseased aorta and to deliver its antibiotic affect. A rapid perioperative coating protocol followed by immediate deployment makes our proposed technique especially useful in an urgent and unstable clinical scenario.

Management of a Mycotic Thoracoabdominal Aortic Aneurysm Involving the Celiac Artery

A mycotic aneurysm that also involves the visceral arteries is a life-threatening condition. Surgical management typically consists of débridement and in situ repair with a Dacron graft and reimplantation of the involved visceral branches. We report a rare case of a mycotic saccular thoracoabdominal aortic aneurysm involving the celiac artery, with Streptococcus pneumoniae as the responsible organism. Successful repair of the aneurysm and concomitant revascularization of the celiac artery were achieved.

Endovascular Repair of Ruptured Infected Arteries as a Temporizing Measure Versus Destination Therapy

Objective:

Mycotic rupture of the arteries is a rare but deadly disorder. Current management typically involves open surgical repair. However, endovascular repair is a potential treatment that can be used to delay open repair, especially in acutely unstable patients. A case report and review of the literature was conducted to determine whether endovascular therapy could be a destination therapy for patients with arterial rupture secondary to infection.

Methods:

We present the case of a 72-year-old man with a left common iliac artery aneurysm rupture secondary to Salmonella infection treated with endovascular therapy upon initial presentation. A literature review of PubMed yielded 29 patients with ruptured aortic and iliac infected aneurysms that were initially treated with endovascular repair.

Results:

Majority of the patients (76.7%, 23 of 30) were successfully treated with the endovascular treatment and did not require open revision. These patients were often placed on long-term antibiotics.

Conclusion:

The literature review supports endovascular repair with a stent graft as a temporizing measure for infected ruptured arteries in an emergent setting and, in select cases, as a destination therapy.