From the Research
The best method for below-knee angioplasty is balloon angioplasty with selective stenting as needed, using a tibiopedal approach when standard antegrade access is challenging, and considering the use of drug-coated balloons for complex lesions to reduce restenosis rates, as supported by the most recent study 1.
Key Considerations
- The procedure typically begins with administration of anticoagulation (unfractionated heparin 70-100 units/kg) to achieve an activated clotting time of 250-300 seconds.
- For the intervention, low-profile balloons (2-3mm diameter) specifically designed for tibial vessels are recommended, with inflation times of 2-3 minutes at nominal pressure.
- Drug-coated balloons may be considered for complex lesions to reduce restenosis rates, as shown in the study 1, which demonstrated a significant reduction in late lumen loss and occlusive restenosis compared to plain old balloon angioplasty.
- Stenting should be reserved for flow-limiting dissections or residual stenosis >30% after balloon angioplasty, with dedicated below-knee nitinol stents preferred.
Post-Procedure Care
- Post-procedure, dual antiplatelet therapy with aspirin 81mg daily indefinitely and clopidogrel 75mg daily for at least 1-3 months is recommended.
- Technical success is optimized by using intraprocedural imaging like digital subtraction angiography with multiple views and adjunctive measures such as vasodilators (nitroglycerin 100-200mcg intra-arterially) to prevent vasospasm.
Rationale
This approach is preferred because below-knee vessels are small-caliber, prone to dissection, and have high rates of calcification, making primary stenting less favorable due to higher risk of restenosis and fracture in these distal vessels, as noted in the study 2. The use of drug-coated balloons, as supported by the most recent study 1, can help reduce restenosis rates and improve outcomes in patients with critical limb ischemia undergoing below-knee angioplasty.