What are the treatment options for a patient with a catheterization showing occlusion due to a clot?

Treatment of Catheter-Detected Occlusion Due to Clot

For coronary artery occlusion detected on catheterization, immediate mechanical restoration of blood flow via percutaneous coronary intervention (PCI) with thrombectomy and/or stent placement is the primary treatment, combined with dual antiplatelet therapy and anticoagulation. 1

Coronary Artery Occlusion

Immediate Mechanical Intervention

• Mechanical restoration of coronary blood flow through immediate coronary angioplasty or stent placement is the definitive treatment for coronary artery thrombosis in patients large enough for adult catheters 1
• Thrombus aspiration catheter devices should be used to remove clot burden before or during PCI 1
• Procedures should be performed by or with assistance of experienced interventional cardiologists to reestablish perfusion as quickly as possible 1

Pharmacologic Adjuncts

• Administer aspirin and a P2Y12 inhibitor (ticagrelor or prasugrel preferred over clopidogrel in acute settings) immediately 1
• Glycoprotein IIb/IIIa inhibitor (abciximab 0.25 mg/kg bolus over 30 minutes, followed by 0.125 μg·kg⁻¹·min⁻¹ for 12 hours) should be considered for large thrombus burden 1
• Systemic anticoagulation with heparin must be initiated immediately 1

Thrombolytic Therapy

• Thrombolytic therapy (alteplase, reteplase, or urokinase) is indicated for coronary artery thrombosis with actual or impending occlusion when mechanical intervention cannot be performed expeditiously 1
• Reduced-dose thrombolytic therapy combined with glycoprotein IIb/IIIa inhibitor is sometimes used for large thrombus burden 1
• Thrombolytics should be administered with low-dose aspirin and low-dose heparin, with careful monitoring for bleeding (maintain fibrinogen >100 mg/dL) 1

Peripheral Arterial Occlusion

Acute Limb Ischemia

• Catheter-directed thrombolysis is the preferred initial treatment for acute limb ischemia (Rutherford categories I and IIa) of less than 14 days' duration 1
• Immediate anticoagulation with heparin should be started before any intervention 1
• Mechanical thrombectomy devices can be used as adjunctive therapy 1

Treatment Algorithm by Vessel Type

• Native-vessel thrombosis: Trial of catheter-directed thrombolysis for viable limbs when guidewire can be passed across the lesion 1
• Embolic occlusions: Isolated suprainguinal emboli should be removed surgically; distal embolization requires catheter-directed thrombolytic therapy 1
• Occluded bypass grafts: Catheter-directed thrombolysis is preferred for grafts occluded <14 days 1

Thrombolytic Agents and Protocols

• Alteplase, reteplase, and urokinase are the most frequently used agents with various infusion protocols 1
• Ultrasound-assisted pharmacologic thrombolysis may reduce infusion duration 1
• Suction embolectomy and rheolytic therapy are useful when thrombolysis is contraindicated 1

Central Venous Catheter Occlusion

Initial Assessment

• For catheter dysfunction, first exclude mechanical causes (malposition, kinks, catheter tip against vessel wall) before treating as thrombotic occlusion 1, 2
• Catheter that has migrated should be repositioned; inadequate length catheters should be exchanged over guidewire 1

Thrombolytic Treatment Protocol

• Alteplase (Cathflo Activase) is the agent of choice for catheter occlusion: 2 mg in 2 mL for patients ≥30 kg; 110% of internal lumen volume (not exceeding 2 mg in 2 mL) for patients <30 kg 1, 2
• Instill alteplase into the occluded catheter with 30-minute dwell time, then assess function by attempting to aspirate blood 2
• If catheter remains nonfunctional after 120 minutes, a second dose of equal amount may be instilled 2
• Overall clearance rate is 86% after up to two doses 2

Alternative Agents

• Reteplase may achieve similar efficacy with shorter dwell times (mean 38 minutes) 1
• Recombinant urokinase clears 60% of catheters at 30 minutes with 73% overall clearance 1

Catheter-Related Venous Thrombosis

Anticoagulation Management

• Low molecular weight heparin (LMWH) subcutaneously or unfractionated heparin intravenously is the main initial therapy for catheter-related venous thrombosis 1
• Continue anticoagulation for minimum 3 months at therapeutic doses 1, 3
• After 3 months, switch to prophylactic doses until catheter removal 1

Catheter Removal Considerations

• When catheter is no longer necessary or long-term anticoagulation is contraindicated, administer 3-5 days of anticoagulation before removal to prevent clot embolization 1
• If symptoms progress or clot extends into superior vena cava, remove the catheter 1

Critical Pitfalls to Avoid

• Never delay anticoagulation while awaiting imaging if clinical suspicion is high and no contraindications exist 3
• Do not apply vigorous suction during attempts to determine catheter occlusion, as this may damage the vascular wall or collapse soft-walled catheters 2
• Avoid excessive pressure when instilling thrombolytic agents, which could rupture the catheter or expel clot into circulation 2
• Do not discontinue both antiplatelet agents simultaneously in patients with recent coronary stent placement, as this dramatically increases stent thrombosis risk 1
• Thrombolytic treatment is not recommended as first-line therapy for catheter-related thrombosis due to greater bleeding risk compared to anticoagulation alone 1
• Using catheter-directed thrombolytics in patients with infected catheters may release localized infection into systemic circulation 2