Registry Studies Optimal Degree of Heparin Anticoagulation for PVI

November 29, 2010—Christos Kasapis, MD, et al have published findings from a study to determine the optimal degree of heparin anticoagulation for peripheral vascular interventions (PVIs). The investigators sought to correlate total heparin dose and peak procedural activated clotting time (ACT) with postprocedural outcomes in patients undergoing PVI. The study has been published online ahead of print in Circulation: Cardiovascular Interventions.

As detailed by the investigators, of 4,743 patients who received heparin during PVIs in a regional, multicenter registry, 1,246 had recorded peak procedural ACT with the same point-of-care device. Periprocedural and in-hospital outcomes were compared between patients who received a total heparin dose < 60 U/kg (n = 2,161) and ≥ 60 U/kg (n = 2,582). Similarly, outcomes were evaluated between groups with a peak procedural ACT < 250 seconds (n = 855) and ≥ 250 seconds (n = 391). Technical and procedural success as well as intraprocedural thrombotic events did not differ between groups.

The investigators reported that patients with heparin dose ≥ 60 U/kg had a higher rate of postprocedural hemoglobin drop ≥ 3 g/dL (7.09% vs 5.09%; P = .004) and a higher transfusion rate compared with those with heparin dose < 60 U/kg (4.92% vs 3.15%; P = .002). In multivariate analysis, independent predictors of bleeding requiring transfusion were total heparin dose ≥ 60 U/kg, ACT ≥ 250 seconds, female sex, age ≥ 70 years, previous anemia, previous heart failure, low creatinine clearance, hybrid vascular surgery, rest pain, and below-knee intervention. In propensity-matched, risk-adjusted models and after hierarchical modeling, total heparin dose ≥ 60 U/kg and ACT ≥ 250 seconds remained strong predictors of post-PVI drop in hemoglobin ≥ 3 g/dL or transfusion.

During PVI, higher total heparin dose (≥ 60 U/kg) and peak ACT ≥ 250 seconds were predictors of postprocedural transfusion. The high technical and procedural success in all groups suggests that use of weight-based heparin dosing with a target ACT < 250 seconds in PVI may minimize the bleeding risk without compromising procedural success or increasing thromboembolic complications, the investigators concluded.