Role of Prolonged Intravenous Heparin in Unstable Angina Patients Prior to Coronary Angioplasty

Background: The optimal timing of coronary angioplasty in unstable angina patients is controversial. Early reports suggested using 3–5 days of intravenous heparin and aspirin for plaque stabilization before angioplasty. There is no clearcut data in this regard from the published literature. The purpose of this study was to evaluate whether delaying the angioplasty in order to stabilize the plaque affected the outcome. Methods: We reviewed the hospital course of patients who were admitted with unstable angina through the emergency room and ruled out for myocardial infarction, and who required angioplasty during the index hospitalization. To diminish the influence of coronary stenting and glycoprotein IIb/IIIa receptor blockade, we reviewed all patients admitted during 1994. Results: Of the 305 patients, 166 patients received ≤48 hours and 139 patients received > 48 hours of intravenous heparin infusion before angioplasty. Both groups were well-matched. The procedural success was similar in both the groups (98% vs 97%, P = 0.72). The complication rate was similar in both groups, including abrupt closure, emergency bypass surgery, myocardial infarction and death. Length of hospital stay was significantly prolonged in the group with > 48 hours of heparin infusion (4.4 ± 3.0 vs 7.4 ± 3.6 days; P < 0.001). Conclusion: In patients with unstable angina undergoing angioplasty, prolonged duration of heparin infusion influenced the procedural outcome or postprocedural complications, but prolonged the hospital stay. These data suggest that early angioplasty of unstable angina patients is safe and may be cost-effective, even in the absence of stenting and potent antiplatelet agents. However, prospective, randomized trials are needed to clarify the need for and duration of heparin infusion prior to angioplasty in unstable angina patients.