I82.220

Acute embolism and thrombosis of inferior vena cava

Acute embolism and thrombosis of the inferior vena cava (IVC) is a life-threatening vascular condition characterized by the sudden formation or lodgment of a blood clot within the largest vein responsible for returning deoxygenated blood from the lower extremities and abdomen to the heart. Unlike typical distal deep vein thrombosis (DVT), IVC involvement carries a significantly higher risk of massive pulmonary embolism and multi-organ dysfunction due to venous hypertension in the kidneys and liver. The condition is frequently associated with pre-existing risk factors such as malignancy (particularly renal or hepatic), mechanical compression from retroperitoneal processes, or complications from indwelling IVC filters. Clinical management typically requires aggressive anticoagulation, and in severe cases, mechanical thrombectomy or thrombolysis to prevent irreversible venous stasis and phlegmasia cerulea dolens.

Clinical Symptoms

Sudden onset bilateral lower extremity edema
Lower back pain and pelvic heaviness
Abdominal wall collateral vein distension (caput medusae-like appearance)
Painless or painful swelling of the legs
Venous claudication (aching or tightness in legs upon walking)
Cyanosis or purplish discoloration of the lower limbs
Symptoms of pulmonary embolism (acute dyspnea, pleuritic chest pain)
Oliguria or renal dysfunction (if thrombosis involves renal vein ostia)
Fever and elevated heart rate

Common Causes

Malignancy (Renal cell carcinoma, Hepatocellular carcinoma, Pancreatic cancer)
IVC Filter Complications (Thrombosis at the site of the filter)
Inherited Hypercoagulable States (Factor V Leiden, Protein C or S deficiency)
External compression (Retroperitoneal fibrosis, Lymphadenopathy, Pregnancy)
Iatrogenic injury (Femoral vein catheterization or venous stenting)
Congenital anomalies of the IVC (Agenesis or hypoplasia)
Trauma to the abdomen or pelvis
Nephrotic syndrome (associated with renal vein extension)

Documentation & Coding Tips

Explicitly define the temporal nature of the thrombosis as acute rather than chronic or unspecified.

Example: Patient presents with sudden onset of lower extremity edema and flank pain. Computed tomography angiography reveals a fresh, non-adherent thrombus in the infrarenal segment of the inferior vena cava. Acute nature is confirmed by the absence of collateral venous channels and the presence of vessel distension. Billing Focus: Acute status (I82.220) and anatomical site (Inferior Vena Cava). Risk Adjustment: Maps to HCC 108 (Vascular Disease), requiring documentation of acute management and systemic anticoagulation plan.

Billing Focus: Acute vs Chronic temporal status.

Document the precise anatomical segment of the inferior vena cava involved, such as infrarenal, suprarenal, or intrahepatic.

Example: Diagnostic imaging confirms an acute thrombus of the inferior vena cava located specifically in the suprarenal segment, extending towards the hepatic vein confluence. No extension into the right atrium is noted. Billing Focus: Specificity of the IVC segment. Risk Adjustment: Higher clinical complexity due to potential involvement of renal and hepatic venous return.

Billing Focus: Anatomical specificity of the IVC segment.

Note the presence and status of any inferior vena cava filters, including whether the thrombus is proximal or distal to the device.

Example: Evaluation of the inferior vena cava shows an acute thrombosis occurring superior to a previously placed Greenfield IVC filter. The filter appears stable but is now partially occluded by the new clot. Billing Focus: Presence of mechanical devices and their relationship to the acute event. Risk Adjustment: Captures complexity of device-related complications and secondary vascular events.

Billing Focus: Device-related clinical status.

Identify and link any underlying causes or predisposing factors such as malignancy or inherited hypercoagulable states.

Example: Acute thrombosis of the inferior vena cava in the setting of known metastatic pancreatic adenocarcinoma. The thrombus is considered a paraneoplastic manifestation of the primary malignancy. Billing Focus: Linking underlying conditions to the acute vascular event. Risk Adjustment: Documentation of malignancy (HCC 8-12) alongside vascular disease (HCC 108) demonstrates significantly higher hierarchical risk.

Billing Focus: Causal relationships and comorbidities.

Specify the presence or absence of associated pulmonary embolism or extension into the iliac or renal veins.

Example: Acute embolism and thrombosis of the inferior vena cava with extension into the bilateral common iliac veins. No evidence of pulmonary embolism on concurrent CT chest. Billing Focus: Extension into additional vascular structures. Risk Adjustment: Multi-site thrombosis indicates higher acuity and supports the need for intensive anticoagulation therapy.

Billing Focus: Extension to related vascular structures.

Relevant CPT Codes

37191 - Insertion of intravascular vena cava filter
Standard procedural intervention for patients with acute IVC thrombosis who cannot tolerate anticoagulation.
37193 - Retrieval of intravascular vena cava filter
Performed once the acute thrombotic risk has subsided or the filter is no longer needed.
75825 - Venography, caval, inferior, with serialography, radiological supervision and interpretation
Primary diagnostic and intra-procedural imaging modality for confirming IVC thrombosis.
93970 - Duplex scan of extremity veins including responses to compression and other maneuvers; complete bilateral study
Often the initial screening tool for suspected venous thromboembolism that may involve the IVC.
99214 - Office or other outpatient visit for the evaluation and management of an established patient
Standard level for managing a patient on complex anticoagulation for an acute IVC thrombus.
99215 - Office or other outpatient visit for the evaluation and management of an established patient
Used for patients with acute IVC thrombosis complicated by other factors like malignancy or pulmonary embolism.
99205 - Office or other outpatient visit for the evaluation and management of a new patient
Initial consultation for a newly diagnosed acute IVC thrombus in a complex patient.
37211 - Transcatheter therapy, arterial or venous infusion for thrombolysis; initial day
Aggressive treatment for extensive acute IVC thrombosis to prevent post-thrombotic syndrome.
99213 - Office or other outpatient visit for the evaluation and management of an established patient
Follow-up for stable patients in the subacute or recovery phase of IVC thrombosis management.
37192 - Repositioning of intravascular vena cava filter
Required if the filter has migrated due to the pressure of the acute thrombus.