22981
document
Reactivation of unstable angina after the discontinuation of heparin . BACKGROUND Heparin is an effective , widely used treatment for unstable angina . Among patients enrolled in a double-blind , randomized , placebo-controlled trial comparing intravenous heparin , aspirin , both treatments , and neither during the acute phase of unstable angina , we encountered patients in whom unstable angina was reactivated after heparin was discontinued . METHODS The study population included 403 of the original 479 patients in the trial who had completed six days of blinded therapy without refractory angina or myocardial infarction . After the discontinuation of therapy , clinical events , including reactivation of unstable angina and myocardial infarction occurring within 96 hours after hospitalization , were closely monitored . RESULTS Early reactivation occurred in 14 of the 107 patients who received heparin alone , as compared with only 5 patients in each of the other three study groups ( P less than 0.01 ) . These reactivations required urgent intervention ( thrombolysis , angioplasty , or coronary-bypass surgery ) in 11 patients treated with heparin alone , but in only 2 patients in the other groups combined ( P less than 0.01 ) . Four of the six patients who had a myocardial infarction during a reactivation of their disease were in the heparin group . Reactivations in this group occurred in a cluster a mean ( +/- SD ) of 9.5 +/- 5 hours after the discontinuation of the study drug but were randomly distributed over the initial 96 hours in the other three groups . CONCLUSIONS Although heparin is beneficial in treating unstable angina , the disease process may be reactivated within hours of the discontinuation of this drug . Concomitant therapy with aspirin may prevent this withdrawal phenomenon .
22982
Intervention_Pharmacological
heparin
22983
Intervention_Pharmacological
Heparin
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Intervention_Control
placebo-controlled trial
22985
Intervention_Pharmacological
intravenous heparin
22986
Intervention_Pharmacological
aspirin
22987
Intervention_Other
both treatments
22988
Intervention_Pharmacological
heparin
22989
Intervention_Pharmacological
heparin
22990
Intervention_Pharmacological
heparin
22991
Intervention_Pharmacological
heparin
22992
Outcome_Physical
Reactivation of unstable angina
22993
Outcome_Physical
clinical events , including reactivation of unstable angina and myocardial infarction occurring within 96 hours after hospitalization
22994
Outcome_Physical
Early reactivation
22995
Outcome_Physical
reactivations
22996
Outcome_Physical
myocardial infarction
22997
Outcome_Physical
Reactivations
22998
Outcome_Physical
reactivated
22999
Participant_Condition
unstable
23000
Participant_Sample-size
403