A Case of Endoleaks from an Endovascular Prosthesis for Aortic Aneurysm

Georges Jabbour^*
*Correspondence: Georges Jabbour, Department of Medicine, University of Pittsburgh, USA, Tel: 961718921677, Email: ,

Keywords

Endoleaks • Cardiovascular • Aneurysm • Endovascular • Prosthesis

Introduction

One of the conditions that require surgery on the aorta is the thoracic aortic aneurysm. It is a loss of parallelism between the walls of the aorta causing dilation. The risk of rupture becomes significant when this expansion reaches a certain threshold generally defined by a diameter ≥ 5.5 cm, and/or a growth rate ≥ 1 cm/year [1].

The thoracic aorta is divided into three segments: the ascending aorta, the descending aorta and the aortic arch. The most often affected part is usually the ascending aorta which is the cause of the majority of operations for an aortic aneurysm [2].

The etiology of the aortic aneurysm can be divided in two main parties [3]: Congenital diseases like Bicuspidy of the aortic valve, Marfan syndrome or Ehlers-Danlos syndrome, while Acquired diseases are mainly due to Atherosclerosis, arteritis, infections or traumatic events.

The dilation is most often found by chance in asymptomatic patients. It is found during a chest x-ray, CT or MRI scan, echocardiogram or aortography [4]. Severe chest pain may be a sign of rupture or cracking of the aneurysm. The patient must be operated on as a matter of extreme urgency in order to stop or prevent the bleeding. The aneurysm can also sometimes release clot debris which will then occlude the arteries in the legs. More rarely, it can compress adjacent structures such as the intestine, urinary tract or iliac veins.

The main treatment for aortic aneurysm is surgery [5]. The different operating techniques are:

• Replacement of the aortic valve (with a mechanical or biological prosthesis) associated with the replacement of the entire ascending aorta and re-implantation of the coronaries

• Replacement of the entire ascending aorta and re-implantation of the coronaries with preservation of the native aortic valve

• Replacement of the ascending supra-coronary aorta associated with replacement of the aortic valve

• Replacement of the ascending supra-coronary aorta

• Replacement of the aortic arch.

Endovascular technique can also be considered [5], this technique involves inserting a prosthesis (a stent) into the aneurysmal aorta through the interior of the femoral arteries. Only two punctures or small incisions are needed at the folds of the groin to insert the stent. This technique has the advantage of being minimally invasive and of presenting a lower risk of mortality and complications than short-term surgery and is usually preferred in elderly patients with comorbidities.

Here we report a case encountered in our service of cardiac surgery concerning an elderly patient treated with an endovascular stent on a preexisting aortic arch prosthesis for endoleak and massive hematic pleural effusion.

Case Report

We present the case of an 88-year-old male presenting to the emergency department for orthopnea and fatigue associated with a cervical pain exacerbated on the extension of the neck. On his arrival, the patient noted several episodes of hypotension reaching 70mmHg of Systolic arterial pressure.

On admission, vital signs were Pulse rate: 129 BPM; SAP: 94 mmHg; DAP: 61 mmHg; SaO₂: 95%; Temperature: 36.7

The patient is known for having an atrial fibrillation treated with Apixaban 2.5 mg per day, Obstructive Sleep apnea treated with CPAP, benign hypertrophic prostate treated by Trans urethral resection of prostate, Chronic renal failure Stage V with dialysis 3 times per week since 2016 and Myelodysplasia. We also note that the patient had an endovascular stent in 2009 for an aortic aneurysm in the ascending and descending aorta.

The procedure done in 2009 was performed at two times:

1. Ascending Aorta and aortic arch prosthesis with Brachiocephalic truncus and left primitive carotid implantation with CABG of LCA, LDA and LMA

2. Endovascular prosthesis of the descending aorta

In Figure 1, we show the Contrast enhanced computed tomography performed after the surgical intervention in 2009 as part of the medical history of our patient.

In the CT- Scan report, we can notice a normal aspect of the ascending aorta where we find the surgical prosthesis beginning at 1 cm after the sinotubular junction. It continues with an endoprosthesis placed percutaneously and covering the descending aorta up to the thoraco-abdominal junction. These are two units with overlap. We note a good coaptation of the endoprosthesis without periprosthetic leakage. The pleural effusion is reduced to 50%.

Abdominal, cardiac, pulmonary and neurological examinations were done systematically, showing a complete abolition of the breath sounds on the left lung, irregular heartbeats with a systolic murmur at the left sternal board. The rest of the examination was normal.

An EKG was performed by the intern showing a rapid Atrial fibrillation at 120 beats per minute but well tolerated by the patient.

A series of examinations was conducted including a complete blood analysis as shown in the Table 1, and an ABG as shown in Table 2.

A CXR performed on the 16^th of April showed a complete left pleural effusion as shown in Figure 2. An injected thoracic CT Scan was then required to elucidate the origin of the pleural effusion, the CT scan is shown in Figure 3.

On the Scan report, the imagery shows the presence of several periprosthetic leak sites; the first of type I is located postero-superiorly at the level of the arch of the aorta starting a few centimeters from the ostium of the left sub clavicular artery, a second of type III located on the anterior wall of the descending aorta and a third probably independent of the previous one but of the same type, lower located at the level of the descending aorta near a prosthetic plicature at this level.

Due to all these findings, an intervention is required via radiologic intervention by implementing an endovascular stent, followed by an evacuation of the pleural effusion with a chest tube.

The intervention was successful with no major complications during the procedure. The chest tube evacuated 3000ml on day 0, 700ml on day 1, 550ml on day 2, 570ml on day 3, 530ml on day 4 and then the chest tube was removed. Hemodynamics of the patient was stabilized in the cardiac intensive care unit.

Discussion

Owing to high rates of immediate success and low morbidity, endovascular stenting has become an alternative to conventional surgery in the treatment of (pseudo) thoracic and/or abdominal aortic aneurysms [5]. Endoleaks, one of the main causes of failure of endovascular procedures [6], are defined as the presence of blood flow outside the prosthesis and within the aneurysm sac. Their rate of occurrence is estimated at 5 to 20% of cases of thoracic and/or abdominal aortic stent grafting [7].

A recent classification similar to the WHITE classification [8] commonly used for infra-renal aortic aneurysms, defines 4 types of endoleaks. The classification is shown in Table 3. Endoleaks can also be classified chronologically: primary endoleaks being discovered within the first 30 postoperative days and secondary endoleaks discovered later.

Treatment of endoleaks

• Type I and III endoleaks present a high risk of breakage due to the absence of exclusion of the aneurysm sac from the systemic circulation. Therefore, the general consensus is to actively treat them as soon as they are identified with either new endovascular procedure or the placement of a covered prosthetic extension (=cuff) or a new endoprosthesis [9].

• Type IV endoleaks, which have become rare with new generations of stent grafts [10], will be treated if they persist beyond one month, as they are then considered to be type III endoleaks.

• There is currently no therapeutic consensus for type II endoleaks [11]. Many authors are increasingly in favor of radical treatment once the diagnosis has been established, because of the participation of these endoleaks in a risk of progress towards rupture. Several therapeutic alternatives are currently proposed [11]. One of them consists of endovascular embolization, that is to say the obliteration of the collateral responsible by the establishment of millimetric metallic foreign bodies (coils), causing thrombosis of the lumen arterial. Another therapeutic option could be laparoscopic vascular surgery, allowing easy control and radical treatment of type II endoleaks using clip, while remaining less invasive than conventional surgery [12]. However, in most cases Type II endoleaks will be treated conservatively by close monitoring, unless expansion continues during monitoring.

In our case, the endoleak is classified as secondary type I and type III endoleaks causing a leakage into the left pleural cavity through the pleural incision done in the Coronary artery bypass Graft, which led to a complete left hemothorax. The patient presented to the ED with hemodynamic instability upon his arrival with a SAP below 70mmHg requiring an immediate intervention.

We preferred not to evacuate the pleural effusion caused by the endoleaks to prevent massive blood loss and extreme hemodynamic instability. Therefore, the patient was driven to the OR with the presence of a cardiothoracic surgeon, an interventional radiologist and an anesthetist.

The endovascular stent was inserted via femoral artery and placed in the aortic arch with close monitoring via aortography. The intervention was successful followed by a chest tube placement. The patient was then monitored in the Intensive care department.

Conclusion

1. We can learn that endovascular approach for endoleaks is safe in elderly patients; a larger data collection is needed in further studies to assess the tolerance and efficiency of this technique in old patients with comorbidities.

2. The diagnosis should be quick with no time to lose, and an immediate intervention is needed to stabilize the patient and preserve his life.

3. Chest Tube must be indicated after the intervention to prevent massive hemodynamic outcomes.

4. Aging is a risk factor and a possible etiology for endoleaks. We suggest in our case that the patient had a displaced stent due to his axial aging which led us to a large questioning about aneurysm stents in patients with a life expectancy that exceeds 10 years from the date of the intervention.

5. Large studies with sufficient data are still required to verify our hypothesis, respond to our concerns and elucidate the outcomes of invasive interventions in elderly patients.

Informed Consent

Written informed consent for the publication of the article was obtained from the patient.

References

1. of the American College of Cardiology 55 (2010): 841-857.
2. Kuzmik Gregory, Adam Sang, and John Elefteriades. "Natural History of Thoracic Aortic Aneurysms." Journal of Vascular Surgery 56 (2012): 565-571.
3. Lu Hong and Alan Daugherty. "Aortic Aneurysms." Arteriosclerosis, Thrombosis, And Vascular Biology 37 (2017): e59-e65.
4. Ho Natalie, Ashley Mohadjer and Milind Desai. "Thoracic Aortic Aneurysms: State of the Art and Current Controversies." Expert Review of Cardiovascular Therapy 15 (2017): 667-680.
5. Rommens Kenton and Anthony Estrera. "Contemporary Management of Aortic Arch Aneurysm." In: Seminars in thoracic and cardiovascular surgery 31 (2019): 697-702.
6. White Geoffrey, Weiyun Yu, James May, Xavier Chaufour, et al. "Endoleak as a Complication of Endoluminal Grafting of Abdominal Aortic Aneurysms: Classification, Incidence, Diagnosis, and Management." Journal of Endovascular Therapy 4 (1997): 152-168.
7. Parmer Shane, Jeffrey Carpenter, William Stavropoulos, Ronald Fairman, et al. "Endoleaks after Endovascular Repair of Thoracic Aortic Aneurysms." Journal of Vascular Surgery 44 (2006): 447-452.
8. Sharafuddin Mel, Brett Reece, Giuseppe Papia, Zlatko Pozeg, et al. "Proposed classification of Endoleaks after Endovascular Treatment of Stanford Type-B Aortic Dissections." Vascular 27 (2019): 585-594.
9. Cao P, Rango P, Verzini F and Parlani G. "Endoleak after Endovascular Aortic Repair: Classification, Diagnosis and Management following Endovascular Thoracic and Abdominal Aortic Repair." Journal of Cardiovascular Surgery 51 (2010): 53.
10. Hinnen JW, Koning OH, Van Bockel JH and Hamming JF. "Aneurysm Sac Pressure after EVAR: The Role of Endoleak." European Journal of Vascular and Endovascular Surgery 34 (2007): 432-441.
11. Stavropoulos William and Sridhar Charagundla. "Imaging Techniques for Detection and Management of Endoleaks after Endovascular Aortic Aneurysm Repair." Radiology 243 (2007): 641-655.
12. Parodi Juan. "Long-Term Outcome after Aortic Endovascular Repair: the Buenos Aires experience." In Seminars in vascular surgery 16 (2003) 113-122. WB Saunders, 2003.