Comparison of heparin therapy for < or = 48 hours to > 48 hours in unstable angina pectoris.
Of 450 consecutive patients with unstable angina admitted to a tertiary care, university-based medical center over a 24-month period, 334 were administered heparin and aspirin for some length of time. Two groups of 98 patients matched for acuity and gender at baseline were treated with either < or = 48 hours (group 1) or > 48 hours (group 2) of heparin. The acuity model used in this study incorporates 6 factors: age, recent myocardial infarction, treatment with intravenous nitroglycerin, previous therapy with beta blockers or calcium antagonists, baseline ST depression, and diabetes. Despite similar risks and overall clinical outcome, group 2 had significantly more myocardial infarction or death after 48 hours than group 1 (p = 0.01). In part, this was due to a delay in the performance of coronary angiography (2.8 +/- 1.4 vs 3.5 +/- 15 days, p = 0.01), coronary intervention (2.7 +/- 1.8 vs 5.1 +/- 2.3 days, p = 0.01), and bypass surgery (3.8 +/- 3.6 vs 7.0 +/- 5.6 days, p = 0.02). There was no difference between groups regarding the success of coronary intervention (90% vs 88%, p = NS). Heparin duration was influenced by the finding of intracoronary thrombus or ulceration on angiography before revascularization, as each finding was seen more often in group 2 (thrombus, 12% vs 24%; ulceration, 38% vs 60%). These results suggest that the optimal duration of heparin therapy is up to 48 hours after admission in unstable angina; a longer time period is associated with increased adverse consequences.
Klein
L W
LW
Rush-Presbyterian-St. Luke's Medical Center and The Rush Heart Institute, Rush Medical College, Chicago, Illinois 60612, USA.
Wahid
F
F
VandenBerg
B J
BJ
Parrillo
J E
JE
Calvin
J E
JE
D000368:Aged; D000789:Angina, Unstable / Q000000981:diagnostic imaging / Q000188:drug therapy*; D015906:Angioplasty, Balloon, Coronary; D001241:Aspirin / Q000627:therapeutic use*; D016022:Case-Control Studies; D017023:Coronary Angiography; D004334:Drug Administration Schedule; D004359:Drug Therapy, Combination; D005260:Female; D005343:Fibrinolytic Agents / Q000627:therapeutic use*; D006493:Heparin / Q000627:therapeutic use*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000517:prevention & control; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use*; D011446:Prospective Studies; D012008:Recurrence; D013997:Time Factors; D016896:Treatment Outcome
D005343:Fibrinolytic Agents; D010975:Platelet Aggregation Inhibitors; D006493:Heparin; D001241:Aspirin