When should I contact interventional radiology for a pulmonary embolism?

When to Contact Interventional Radiology for Pulmonary Embolism

Contact interventional radiology immediately for massive PE with hemodynamic instability when thrombolytic therapy is contraindicated or has failed within the first hour, or for IVC filter placement when anticoagulation is contraindicated or recurrent PE occurs despite adequate anticoagulation. 1

Immediate IR Consultation Required

High-Risk (Massive) PE Scenarios

• Contact IR urgently for patients with systemic hypotension, cardiogenic shock, or cardiovascular collapse when systemic thrombolysis is contraindicated (recent hemorrhage, stroke, current GI bleeding, surgery within 7 days, or prolonged CPR). 1

• Call IR within the first hour if the patient fails to respond to thrombolytic therapy despite receiving 50-100 mg alteplase, as surgical or catheter-based embolectomy becomes the next option. 1, 2

• Involve IR for percutaneous catheter-directed treatment when thrombolysis has failed or is contraindicated in patients with high-risk PE, as this represents a Class IIa recommendation. 1

• Consider IR consultation for ECMO placement in combination with catheter-directed treatment in patients with PE and refractory circulatory collapse or cardiac arrest. 1

IVC Filter Indications

• Contact IR for IVC filter placement in patients at high risk of further emboli when anticoagulation is absolutely contraindicated (active bleeding, recent hemorrhagic stroke). 1

• Involve IR for filter insertion in patients with recurrent PE despite adequate anticoagulation, as this represents a failure of medical therapy. 1

• Ensure filter selection and insertion is performed only by an experienced interventional radiologist, as emphasized by guideline recommendations. 1

Consider IR Consultation (Non-Emergent)

Intermediate-Risk (Submassive) PE

• Discuss with IR for patients with intermediate-risk PE who show clinical deterioration (worsening hemodynamics, respiratory status, or RV function) despite anticoagulation, as catheter-directed therapy may prevent progression to high-risk PE. 1, 3, 4

• Consider catheter-directed thrombolysis for intermediate-risk PE patients with elevated bleeding risk where systemic thrombolysis poses unacceptable hemorrhage risk (10% major bleeding in high-risk patients vs 1% in low-risk). 1, 5

• Involve IR when proximal clot location is documented (main or lobar pulmonary arteries), as endovascular therapy is more effective with proximal thrombus burden. 1

• Contact IR for clot-in-transit cases, particularly if patent foramen ovale is present, due to high risk of "second hit" and systemic embolization. 1

Diagnostic Role of IR

• Request pulmonary angiography through IR when cardiovascular collapse or hypotension is present and the diagnosis needs urgent clarification, as this should be available emergently. 1

• Arrange angiography via IR when other investigations (V/Q scan, spiral CT) have failed to give a firm diagnosis in patients with suspected PE. 1

• Ensure good liaison between IR and intensive care unit for hemodynamically unstable patients requiring angiography, with full resuscitation facilities and continuous monitoring available. 1

Common Pitfalls to Avoid

• Do not delay IR consultation waiting for additional imaging in unstable patients—hemodynamic status takes priority over complete diagnostic workup. 6

• Do not assume all intermediate-risk PE requires IR intervention—the majority can be managed with anticoagulation alone, and there is no single set of criteria that mandates advanced therapy. 1

• Do not request IVC filters for routine PE prophylaxis—they are less effective than thrombolysis in the acute situation and are significantly underused in the UK for appropriate indications. 1

• Recognize that catheter-based therapies carry risks—concerns for procedural hemodynamic or respiratory decompensation exist, particularly with rheolytic thrombectomy (FDA black-box warning for pulmonary hemorrhage and collapse). 1

Multidisciplinary Approach

• Engage a Pulmonary Embolism Response Team (PERT) when available for intermediate-risk and high-risk PE, bringing together cardiology, pulmonology, interventional radiology, cardiac surgery, and critical care to formulate real-time treatment plans. 1, 3, 4

• Ensure IR is part of the multidisciplinary discussion for treatment decisions influenced by bleeding risk, thrombus extent and location, and operator expertise. 1