Physiological indices for evaluating balloon angioplasty outcomes in below-the-knee artery lesions of patients with chronic limb-threatening ischemia.

Purpose: To assess the potential use of resting distal pressure/aortic pressure (Pd/Pa) and constant resistance ratio (cRR) physiological indices in the treatment of tibial artery lesions with balloon angioplasty in patients with chronic limb-threatening ischemia (CLTI).

Methods: In this single-center retrospective study, resting Pd/Pa and cRR measurements were performed using a pressure microcatheter after balloon angioplasty. Procedures were conducted using balloons with diameters of 3 and/or 3.5 mm. The optimal group was defined as patients with either resting Pd/Pa or cRR ≥0.9, whereas the acceptable group included those with both values between 0.8 and 0.9. Clinical improvement in patients with rest pain (Rutherford 4) was defined as at least a 1-point category improvement, indicating a reduction or resolution of rest pain.

Results: The study population consisted of 40 patients (75% men; mean age 64 ± 11.2 years), with a follow-up duration of 92 ± 40.5 days. Foot ulcers were present in 90% of the patients. During follow-up, wound healing was observed in 69.7% of patients. The optimal group exhibited higher rates of wound healing and clinical improvement than the acceptable group, although the difference was not statistically significant (80% vs. 50%, P = 0.151). No patient required target vessel revascularization. The overall limb salvage rate during follow-up was 94.6%.

Conclusion: Short-term follow-up demonstrated favorable rates of wound healing, patency, and limb salvage. The optimal group showed a trend toward improved wound healing and clinical improvement.

Clinical significance: This study highlights the utility of resting Pd/Pa and cRR as reproducible physiological indices for objectively evaluating the success of balloon angioplasty in below-the-knee arteries in patients with CLTI. Physiological assessment can guide procedural decisions, contributing to improved limb salvage and high patency rates.