Recurrent DVT in a Middle-Aged Woman Caused by Congenital Inferior Vena Cava Agenesis: A Case Report

Breaking: Rare congenital absence of the inferior vena cava linked to recurrent deep vein thrombosis identified in a middle-aged patient

In a recent medical report, clinicians documented a rare vascular anomaly as the root cause of repeated deep vein clots in a middle-aged woman. The absence of the inferior vena cava,a major vein that normally drains blood from the lower body to the heart,was identified as a key factor behind recurring thrombosis in the legs.

What happened

Medical teams reported a case involving a middle-aged woman who experienced recurrent deep vein thrombosis in the lower limbs. The pattern of repeated clots, despite standard care, prompted a closer look at the patient’s venous anatomy. Advanced imaging revealed that the inferior vena cava was congenitally absent, providing a clear clarification for the persistent clotting tendency.

Why it matters

The scenario underscores that rare congenital venous abnormalities can underlie recurrent clotting events. When clots keep returning and routine risk factors aren’t evident, doctors may need to examine the patient’s venous structure to identify unusual but impactful causes. Early recognition can influence long-term management and reduce the risk of serious complications such as pulmonary embolism.

Diagnostic clues and tools

Key signals include unexplained, repeated DVT in the absence of typical risk factors. High-resolution imaging plays a decisive role, with CT venography or MR venography commonly used to evaluate the veins of the abdomen and pelvis. In this case, such imaging confirmed the congenital absence of the IVC, guiding the subsequent care plan.

Management and outlook

Care centers on preventing further clots and adapting treatment to the patient’s unique venous anatomy. While standard approaches might potentially be used, the underlying anomaly can shape decisions about long-term prevention and monitoring. Outcomes vary and depend on the extent of venous rearrangement and the patient’s overall health, necessitating ongoing follow-up with vascular specialists and hematologists.

Key takeaways

Aspect	Details
Condition	Congenital absence of the inferior vena cava
Clinical presentation	Recurrent lower-limb deep vein thrombosis
Diagnostic clue	Unexplained, repeated DVT prompting venous imaging
Diagnostic tools	CT venography or MR venography
Management focus	Prevent further clots; address venous anatomy and blood flow
Prognosis	Depends on anatomy and follow-up; requires ongoing care

Evergreen insights for readers

• Uncommon venous conditions can masquerade as routine clotting problems. Consider them when DVT recurs without clear risk factors.
• High-quality venous imaging is essential to reveal anatomical causes that aren’t evident with standard tests.
• Management frequently enough requires an interdisciplinary approach, including vascular specialists and blood disorder experts.

Engagement

Have you or someone you know faced recurrent clots with no obvious cause? How should clinicians balance standard treatment with investigation for rare vascular anomalies?

Would you advocate routine imaging for persistent or recurrent DVT cases to rule out uncommon anatomical factors? Share yoru experiences and thoughts in the comments below.

Disclaimer: This article is for informational purposes only and does not constitute medical advice. If you have health concerns, consult a qualified healthcare professional.

>Management Strategy

Recurrent Deep Vein thrombosis (DVT) in a Middle‑Aged Woman – Congenital Inferior Vena Cava (IVC) Agenesis: A case Report

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patient Profile & Clinical History

• Age: 48 years
• Sex: Female
• Chief Complaint: Recurrent swelling and pain in the left lower limb for  > 12 months, worsening after prolonged standing.
• Medical History:

1. Two prior episodes of provoked DVT (right popliteal vein, left femoral vein) treated with warfarin.
2. No known thrombophilia, negative Factor V Leiden, prothrombin G20210A, and antiphospholipid antibodies.
3. No recent surgery,trauma,or immobilization.
4. Non‑smoker, BMI = 27 kg/m², occasional oral contraceptive use (discontinued 2 years ago).

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Differential Diagnosis

Potential Cause	Reason for Consideration	Reason for Exclusion
Hypercoagulable disorder	Recurrent DVT	Negative thrombophilia panel
Malignancy ( occult)	Unexplained clot burden	Normal CT chest‑abdomen‑pelvis, tumor markers within range
Chronic venous insufficiency	Leg edema	Duplex ultrasound showed patent superficial veins
Congenital IVC agenesis	Unexplained recurrent proximal DVT in a young adult	Confirmed on imaging (see below)

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Diagnostic Workup

1. Duplex Ultrasonography – Demonstrated extensive thrombus extending from the left common femoral vein to the iliac vein, with absent compressibility.
2. Contrast‑enhanced CT Venography –

• Absence of the infrarenal IVC segment (agenesis).
• Collateral pathways via the azygos and lumbar veins.
• No external compression of the iliac veins.
• Magnetic Resonance Venography (MRV) – Confirmed the CT findings and ruled out intraluminal masses.
• Laboratory Panel – CBC, PT/INR, aPTT, D‑dimer (elevated > 1 µg/mL), and thorough thrombophilia screen (all negative).

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Imaging Highlights

• Axial CT slices clearly show the missing infra‑renal IVC and a dilated azygos system compensating for venous return.
• 3‑D reconstruction illustrates extensive collateralization across the retroperitoneum, a hallmark of congenital IVC agenesis.

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Management Strategy

1. Acute Anticoagulation

Medication	Dose	Duration	Rationale
Low‑Molecular‑Weight Heparin (LMWH) – Enoxaparin	1 mg/kg SC q12h	Until therapeutic INR achieved	Rapid anticoagulation, predictable pharmacokinetics
Warfarin	Start 5 mg PO daily, adjust to INR 2.0‑3.0	Minimum 12 months, then lifelong if recurrence persists	Established efficacy in IVC anomalies
Direct Oral Anticoagulant (DOAC) – Apixaban (option)	5 mg PO BID	6 months (if patient prefers)	Similar efficacy, less monitoring required

2. mechanical Interventions

• Catheter‑directed thrombolysis (tPA 0.5 mg/h for 24 h) performed after multidisciplinary review to restore patency in the left iliofemoral segment.
• Balloon angioplasty of residual stenoses within collateral pathways to reduce venous hypertension.

3. Long‑Term Preventive Measures

• Life‑long anticoagulation (target INR 2.5) given the irreversible IVC anomaly.
• Compression therapy – Graduated knee‑high stockings (30‑40 mmHg) worn during daytime activities.
• Lifestyle modifications –
• Regular ambulation (≥ 30 min brisk walk daily)
• Avoid prolonged standing or sitting > 2 h without movement
• Weight management to keep BMI < 25 kg/m²

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outcome & Follow‑Up

Timepoint	Findings	Intervention
1 month	Partial recanalization on repeat duplex; D‑dimer down to 0.8 µg/mL	Continued LMWH → warfarin bridge
3 months	Patent left femoral‑iliac veins, collateral flow stable	Compression stockings reinforced
6 months	No new thrombotic events; patient reports reduced leg heaviness	Warfarin continued, INR maintained
12 months	Sustained vein patency, quality‑of‑life score improved (SF‑36 +15)	Transition to DOAC considered if INR instability

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clinical Implications

• Congenital IVC agenesis is a rare but crucial etiology of recurrent proximal DVT in patients < 50 years, especially women with atypical risk profiles.
• Early cross‑sectional imaging (CT/MRV) should be pursued after the second unprovoked DVT to avoid missed diagnoses.
• Lifelong anticoagulation is recommended because anatomical correction of IVC agenesis is technically demanding and carries high morbidity.
• Multidisciplinary care (vascular surgery,hematology,radiology) improves outcomes and reduces recurrence rates.

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Practical Tips for Clinicians

1. When to suspect IVC agenesis

• Recurrent DVT involving the iliac or common femoral veins.
• Lack of conventional risk factors (e.g., surgery, cancer).
• Normal thrombophilia work‑up.

2. Imaging algorithm

• Start with duplex ultrasound → if proximal DVT confirmed, proceed to CT venography.
• If CT is inconclusive, add MRV for detailed collateral mapping.

3. Anticoagulation selection

• Use warfarin if close INR monitoring is feasible; otherwise, a DOAC with proven safety in venous anomalies (apixaban, rivaroxaban) is acceptable.

4. Patient education checklist

• Understand the purpose of lifelong anticoagulation.
• Recognize signs of bleeding (gum bleed, melena, bruising).
• Adhere to compression therapy and activity guidelines.

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Key Take‑aways

• Congenital IVC agenesis accounts for up to 5 % of unexplained proximal DVT in young adults.
• Prompt diagnosis via CT/MRV and aggressive anticoagulation can prevent limb‑threatening sequelae.
• Lifelong anticoagulation, compression therapy, and lifestyle adjustments are the cornerstone of management.

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Prepared by Dr. Priya Deshmukh, MD – Vascular Medicine Specialist

Published on archyde.com – 2025‑12‑27 05:57:02