Aortic Thrombosis Due to a Giant Ovarian Cyst
Article Outline
Abstract
We describe a patient who presented with a giant ovarian cyst causing a complete occlusion of the distal abdominal aorta. An 86-year-old patient presented with acute ischaemia of her lower limbs 3 days after a transurethral resection of a bladder tumour (TURT). She refused treatment for her giant ovarian cyst. The administration of Sintrommitis® was ceased 3 days preoperatively; no bridging anticoagulation therapy was initiated. A computed tomography (CT) angiogram showed a thrombotic occlusion of the distal aorta. We believe this to have been caused by pressure from the giant ovarian cyst. The patient died 2 days later. This case illustrates that awareness is warranted for vascular complications in patients, with a giant intra-abdominal cyst or tumour, undergoing abdominal or pelvic surgery.
Keywords: Anticoagulation, Aortic thrombosis, Giant ovarian cyst
Acute occlusion of the abdominal aorta is a rare clinical emergency with a high mortality rate (20–52%).1, 2, 3, 4
Ovarian cysts frequently occur in post-menopausal women. Cadaveric studies show incidence rates as high as 54%. Majority of these cysts are smaller than 50
mm and are of no clinical consequence. Only a very small percentage of ovarian cysts will develop to giant cysts.5, 6
We report the case of a patient who suffered from a giant ovarian cyst, leading to compression of the distal aorta and subsequent thrombosis. To our knowledge, this case has not been described before.
Case report
An 86-year-old female patient presented to the urology department with complaints of macroscopic haematuria and was admitted to the hospital. Her medical history revealed atrial fibrillation, hypertension, varicose veins, appendectomy and an abdominal hysterectomy. A diagnosis of a giant ovarian cyst had been made 1 year prior to her current admission. The benign character of the cyst and the fact that she did not have complaints made her decide that she did not desire any treatment for it. Two months prior to admission, she had complained of dizziness and nausea in the supine and right decubitus position and hence preferred to sleep on the left side. Her medication on admission comprised acenocoumarol (Sintrommitis®), lanoxin and enalapril.
Cystoscopy revealed a sessile solitary tumour on the right side of the bladder. Analysis of a urine sample showed urothelial cell carcinoma as the reason for macroscopic haematuria. A computed tomography (CT)-intravenous pyelogram showed a bladder tumour, as well as a giant cystic tumour (20cm diameter) originating from the left ovary. A CT examination also revealed a compressed but patent aortic lumen, as well as patent iliac arteries. The aortic compression was sited from 4 cm to 1 cm above the aortic bifurcation (Fig. 1a–c). The patient agreed to undergo a transurethral resection of the tumour (TURT), for which acenocoumarol was ceased 3 days before surgery. No bridging anticoagulants were used. The procedure was performed under spinal anaesthesia. The bladder was distended with approximately 200cc of saline. No difficulties or hypotensive episodes were encountered during or early after surgery.
Figure 1
(a) CT scan of abdomen showing patent iliac arteries, (b) maximum compression of the aorta and (c) patent aorta at cranium of the cyst.
Three days postoperatively, the patient developed signs of acute ischaemia of the lower extremities. A CT angiogram revealed complete occlusion of the distal aorta proximal to the bifurcation caused by a thrombus in a partially compressed lumen due to the known ovarian cyst (Fig. 2). Decompression of the ovarian cyst and aortic thrombectomy or bypass surgery was repeatedly refused by the fully aware patient. The patient died 2 days later as a result of multiple organ failure.
Figure 2
The aorta is filled with contrast medium. Due to compression and thrombosis, no contrast is seen in the distal aorta and the iliac arteries.
Discussion
Cysts originating from the ovaries are observed frequently.5, 6 Majority of these cysts will not become symptomatic. The exact incidence of giant ovarian cysts has never been reported. Drainage of ovarian cysts should be avoided whenever possible since cardiac failure, dyspnoea and pulmonary oedema have been described.7 The option to drain the cyst was considered; however, it was decided that the cyst could be used as a protective shield in case of adjuvant radiotherapy.
In the event of an acute thrombotic occlusion of the aorta, blood flow into the lower extremities is reduced, with resultant pan-ischaemia. Physiological and anatomical studies show that irreversible muscle cell damage is complete after 6h of ischaemia. The toxic products produced by the limb ischaemia lead to multiple organ failure and, eventually, death.8
In retrospect, we believe that the symptoms of nausea and dizziness in the supine and right decubitus position and preference to sleep on the left side were comparable to symptoms of the vena cava syndrome in pregnant women. Preoperatively, however, these were not interpreted as potential haemodynamic effects of the giant cyst.
Calculating pressure on the aorta generated by a cyst is virtually impossible. The tension inside the cyst reflects a force onto the anterior abdominal wall, surrounding tissues and the aorta, vena cava and the spine. A combination of these forces will lead to the exact pressure onto the aorta and is difficult to estimate since many variables are unknown.
The contents of a cyst can be calculated by
Specific gravity (sg) of the cystic contents was not known; however, this can be estimated based on an average CT Hounsfield unit (HU)-value of 25, which would indicate that the cyst was filled with a protein-rich fluid. Based on an sg of approximately 1.025, one can assume that the pressure generated by a 4.3kg, non-compressible ovarian cyst, together with the abdominal wall tension, must have had a profound effect on the aorta and inferior vena cava in the supine position due to gravity.
Since TURT required the bladder to be distended with saline, the anatomically adjacent location of the cyst and bladder in the pelvis indicates that the bladder would push the cyst cephalad against the aortic bifurcation (as illustrated in Figure 1, Figure 2). The additional force of 200ml of saline (approximately 5% of the cystic contents) may well have been the straw that broke the camel's back and caused the aortic thrombosis, unique to TURT and giant cysts in the pelvis, but not to surgery in general. However, the thrombo-ischaemic complication occurred 3 days after surgery. This makes TURT a less likely direct cause of aortic thrombosis.
Based on this knowledge, it is likely that in a supine patient undergoing a TURT, withheld from acenocoumarol therapy and bridging anticoagulants, compression on the aorta by the giant ovarian cyst developed into the aortic occlusion.
This case illustrates that awareness is warranted for thrombotic complications in patients with a giant intra-abdominal cyst or tumour and undergoing a TURT.
Our patient repeatedly refused treatment for the benign cyst. The malignant bladder tumour, however, resulted in treatment by a transurethral resection. In retrospect, treatment of the ovarian cyst prior to TURT was indicated.
To our knowledge, this is the only reported case of an aortic thrombosis resulting in occlusion caused by a giant ovarian cyst.
Conclusion
An 86-year-old female patient with a known giant ovarian cyst underwent a TURT because of a sessile solitary bladder tumour. Three days postoperatively, she developed signs of acute ischaemia of the lower extremities. A CT angiogram showed total occlusion of the distal aorta as a result of compression and thrombosis due to the giant ovarian cyst. No further therapeutic interventions were desired by the patient. She died 2 days after the onset of symptoms.
In patients with giant intra-abdominal cysts or tumours, pre-existing conditions should be taken into consideration prior to surgery, as well as the institution of bridging therapy with anticoagulants.
Acknowledgement
We thank S.R. Brouwer, retired physics high school teacher for his contribution.
The authors declare that there are no competing interests.
References
- . Acute aortic occlusion – factors that influence outcome. J Vasc Surg. 1995;21(4):567–572discussion 573–65
- . The diagnosis and treatment of acute aortic occlusions. J Mal Vasc. 1996;21(3):133–135
- Acute aortic occlusion. A 40-year experience. Arch Surg. 1994;129(6):603–607discussion 607–08
- . Acute occlusion of the abdominal aorta. Am J Surg. 1998;176(2):193–197
- . Prevalence and histologic diagnosis of adnexal cysts in postmenopausal women: an autopsy study. Am J Obstet Gynecol. 2005;192(1):48–54
- . Frequency and type of adnexal lesions in autopsy material from postmenopausal women: ultrasound study with histological correlation. Ultrasound Obstet Gynecol. 2003;22(3):284–289
- . Giant ovarian cysts: is a pre- and intraoperative drainage an advisable procedure?. Int J Gynecol Cancer. 2006;16(6):2039–2043
- . The pathophysiology of skeletal muscle ischemia and the reperfusion syndrome: a review. Cardiovasc Surg. 2002;10(6):620–630
PII: S1533-3167(08)00034-4
doi:10.1016/j.ejvsextra.2008.11.010
© 2009 European Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.
