Right ovarian vein and inferior vena cava thrombosis after caesarean section

Clinical History

37-year-old woman, one day after caesarean delivery, developed severe vaginal bleeding with hypovolaemic shock. The initial suspicion was uterine atony, and a hysterectomy was decided. After the surgery hypotension continued associated with lower abdominal pain, and persistence of bleeding was suspected. Arteriography was indicated.

Imaging Findings

The arteriography did not show any bleeding site, but it revealed a left ureterohydronephrosis with a stop in the distal left ureter (Fig. 1). A computed tomography was performed, showing right ovarian vein thrombosis extending into the inferior vena cava and asymptomatic pulmonary embolism (Fig. 2, 3). Due to contraindication for anticoagulation, a cava filter was indicated.
The patient was brought to the angiographic suite, and an infra-renal retrieval cava filter was placed. One week later, a new CT showed progression of the thrombus surrounding and above the filter (Fig. 4). It required a second retrieval cava filter to be placed above the renal veins and below the hepatic veins (Fig. 5).
She underwent a new laparotomy in order to treat ureter injury due to iatrogenic section. Ligation and transection of the thrombosed right ovarian vein were performed.
Two months later the cava filters were retrieved without any complication (Fig. 6).

Discussion

Postpartum ovarian vein thrombosis (OVT) is a rare puerperal complication with a low incidence; prompt diagnosis and treatment can decrease the morbidity of this disease [1-2].
Pathophysiologically, OVT is explained by the hypercoagulable state associated with pregnancy, venous stasis due to uterus compression of the inferior vena cava, in addition to endothelial trauma during delivery, infection, caesarean section or pelvic surgery. During pregnancy, ovarian vein diameters increase 3-fold, flow capacity becomes 60 times greater and valvular incompetence is exacerbated.
In 80-90% of the cases, the right ovarian vein is affected.
OVT occurs in 1-2% of caesarean deliveries [3].
In 90% of cases it presents within the first 10 days after delivery. Ovarian vein thrombosis may present with a broad range of symptoms, but the most common symptoms are fever in 80% and pelvic pain and palpable abdominal mass in 50% of cases. Other non-specific symptoms are: back pain, nausea, vomiting, tachycardia, ileus or sepsis [1]. In those complex cases, CT or MRI can help lead the diagnosis.
The severity of OVT is related to the extension of the thrombosis into the inferior vena cava and the possibility to develop a pulmonary embolism (PE).
Our patient suffered numerous serious complications; therefore it was difficult to reach the diagnosis in the first instance. Probably the OVT was due to the hysterectomy but the previous bleeding delayed the correct diagnosis. After arteriography, secondary haemorrhage to vessel injury was ruled out.
In literature, OVT has been reported as a complication of caesarean hysterectomy in 0.5% [4]. Pulmonary embolism as a complication of OVT has been reported in 13.2%, but due to the paucity of reports, this incidence is not available [1].
The usual treatment for OVT is anticoagulants and antibiotics, and in cases in which there is a contraindication to anticoagulation and the ovarian vein thrombosis extends into the IVC or renal vein, placing a filter becomes an emergency. Due to previous hysterectomy in our patient, anticoagulation was contraindicated. The first filter was placed below the renal veins but as a consequence of the progression of the thrombus the second filter placement was mandatory.
Placement and retrieval of these filters have a low risk of complications and offer an effective and safe treatment [5].

In summary, the diagnosis and treatment of OVT is crucial to prevent severe complications and rapid detection requires a high index of suspicion in these puerperal patients.

Differential Diagnosis List

Final Diagnosis

Right ovarian vein and inferior vena cava thrombosis complicated with pulmonary embolism.

URL:	https://www.eurorad.org/case/12693
DOI:	10.1594/EURORAD/CASE.12693
ISSN:	1563-4086