Balloon-Assisted Catheter-Directed Thrombolysis for Acute Limb Ischemia: A Multi-Center Retrospective Cohort Study

Abstract

Background:

Catheter-directed thrombolysis (CDT) is a first-line therapy for Rutherford IIa acute limb ischemia (ALI). However, 20% to 30% of patients exhibits suboptimal response. Balloon-assisted CDT (BA-CDT), which combines mechanical thrombus disruption with continued thrombolysis, offers a potential escalation strategy.

Methods:

A multi-center, retrospective cohort study was conducted across 3 tertiary vascular centers from January 2022 to June 2025. Consecutive patients with Rutherford IIa ALI who demonstrated suboptimal clinical and/or angiographic response to initial CDT, based on predefined criteria (eg, lack of clinical improvement, >50% residual thrombus, and poor tibial runoff) were escalated to BA-CDT. The primary endpoint was limb salvage at 30 days. Secondary endpoints included technical success clinical improvement (≥0.15 ankle-brachial index [ABI] increase), target lesion primary patency (TLPP) at 6 months, and procedure-related complications. Propensity score adjustment was used to account for baseline differences between the BA-CDT cohort and patients who responded to CDT alone.

Results:

Among 124 patients undergoing CDT, 34 patients (27.4%) were escalated to BA-CDT. Technical success was achieved in all cases. The median ABI improved significantly from 0.06 at baseline to 0.77 post-BA-CDT (p<0.001). Limb salvage was achieved in 94.1% of the patients. Target lesion primary patency rates were 94.1%, 82.4%, and 64.7% at 1, 3, and 6 months, respectively. Complications included access-site hematoma (17.6%) and distal embolization (14.7%). Cox regression identified an escalation time exceeding 12 hours (hazard ratio [HR] 8.87, p=0.04) and occurrence of distal embolization (HR 3.79, p=0.05) as independent predictors of TLPP loss. After propensity score adjustment, outcomes for the BA-CDT group (which had more complex baseline anatomy) were comparable with those of the CDT-only group in terms of limb salvage, patency, and major complications.

Conclusion:

For patients with ALI who do not respond adequately to initial conventional deep vein thrombosis treatment (CDT), escalating to BA-CDT is a safe and effective strategy. This approach improves blood flow, achieves high limb salvage rates, and is a resource-efficient alternative to advanced thrombectomy devices or surgical interventions within a standardized treatment algorithm.

Clinical Impact

This study establishes balloon-assisted catheter-directed thrombolysis (BA-CDT) as an effective, stepwise approach for treating Rutherford IIa acute limb ischemia patients who do not respond adequately to initial thrombolysis. By utilizing standard balloons instead of expensive mechanical thrombectomy devices, clinicians can disrupt thrombus mechanically, improve drug penetration, and address underlying lesions. The protocol outlines specific angiographic and clinical criteria for timely escalation (within 12 hours), achieving a limb salvage rate of 94% even in complex, multilevel occlusions. In resource-limited settings, BA-CDT provides an accessible and effective rescue option before surgical intervention, potentially lowering amputation rates and healthcare costs while ensuring patient safety.