A safety and feasibility report of combined direct thrombin and GP IIb/IIIa inhibition with bivalirudin and tirofiban in peripheral vascular disease intervention: treating critical limb ischemia like acute coronary syndrome.

BACKGROUND: The combination of glycoprotein (GP) IIb-IIIa inhibition and direct thrombin inhibition (DTI) with bivalirudin (Angiomax, The Medicines Company, Cambridge, Massachusetts) have shown ischemic and hemorrhagic outcomes benefit in coronary interventions and may have similar benefits in percutaneous peripheral interventions (PPI). The high incidence of diabetes, chronic renal disease, platelet dysfunction, hypercoagulability, inflammation and a thrombus-rich environment make a GP IIb-IIIa and DTI combination with tirofiban (Aggrastat Merck and Company, Inc., Whitehouse Station, New Jersey) an attractive anticoagulation strategy in the PPI treatment of critical limb ischemia (CLI). METHODS: Between May 1, 2001 and January 31, 2003, a CLI treatment group of 149 patients received PPI with bivalirudin (0.75 mg per kg bolus with 1.75 mg per kg per hour periprocedural infusion) and tirofiban (10 mcg per kg per minute bolus with 12-hour 0.1 mcg per kg per minute infusion) as an anticoagulation and antiplatelet strategy, and were compared to a matched unfractionated heparin (UFH) control group without GP IIb-IIIa inhibitors. Clinical and hemostasis outcomes were analyzed, including distal embolization (DE). RESULTS: Procedural success was 95.9% and 97.3% in the UFH control group and DTI-GP IIb-IIIa group, respectively. Significant differences were observed in the sheath removal time < 2 hours (60.5% UFH group versus 19.4% DTI-GP IIb-IIIa group; p = < 0.0001). Vascular closure devices were used equally in both groups. No statistical significance was observed in major and minor complications, femoral access complications, acute (< 48 hours) or subacute (30 days) vessel thrombosis, and 6-month duplex ultrasound restenosis rate between the DTI-GP IIb-IIIa versus the UFH group. A trend towards statistical significance was observed in the 6-month secondary re-intervention and limb salvage rates (10.7% versus 18.8%; p = 0.0501 and 93.9% versus 88.5%; p = 0.053) in the DTI-GP IIb-IIIa versus the UFH group, respectively. Angiographically relevant DE occurred in 4 of 149 (1.3%) and 8 of 149 (5.4%) of the bivalirudin-tirofiban and UFH groups, respectively. CONCLUSION: The combination of DTI with bivalirudin and GP IIb-IIIa inhibition with tirofiban is a safe and feasible alternative anticoagulation and antiplatelet strategy in PPI, and may offer improved clinical and hemostasis outcomes in treating CLI. A larger, prospective randomized trial is warranted.

Critical limb ischemia: a global epidemic.A critical analysis of current treatment unmasks the clinical and economic costs of CLI.

BACKGROUND: Multiple reports document the higher costs of primary amputation (PA) compared to infrainguinal bypass surgery (IBS). Recent reports document 40-50% cost-effectiveness for percutaneous transluminal angioplasty (PTA) compared to IBS. The literature suggests appropriate initial treatment for critical limb ischemia (CLI) to be IBS = 38%, PTA = 28%, and PA = 16%. The encouraging 6-month Laser Angioplasty for Critical Limb Ischemia (LACI) 93% limb salvage rate prompted an independent CLI and LACI clinical and economic analysis. METHODS: Between 1999-2001 a reference amputation population (RAP) of 417 patients with at least one infrainguinal amputation were identified from a 2.5 million patients Medicare/insurance dataset. Clinical data and all medical cost claims for 18 continuous months, 12-month prior and 6-month post-amputation, were analyzed for PTA, IBS, and PA treatment pathways. Based on multiple assumptions and the LACI phase II results, economic outcomes were used for a LACI pathway analysis compared to PTA, IBS and PA pathways by substituting the LACI trial pathway as the initial treatment in lieu of the RAP actual treatment. RESULTS: Initial treatments for CLI RAP were PA = 67%, IBS = 23%, PTA = 10%; A majority of wound complications (80%) and myocardial infarction 7/9 (77.7%), stroke 13/16 (81.2%), and death 2/2 (100%) occurred in the PA RAP. Only 35% of the RAP had an ankle brachial index (ABI) and only 16% angiography before PA. 227/417 (56%) of the RAP had multiple procedures. Average total costs / patient = $31,638 without LACI and $25,373 with LACI. Average savings/patient with LACI = $6,265. CONCLUSION: The most common current treatments in the US for CLI are still characterized by high rates of primary amputations, multiple procedures, and high rates of procedure-related complications. Despite the limitations and assumptions of this analysis, the utilization of a LACI pathway first revascularization treatment strategy may provide clinical and economic cost savings in treating patients with CLI.