TREATING MENSTRUATING WOMEN WITH THROMBOLYTIC THERAPY - INSIGHTS FROMTHE GLOBAL UTILIZATION OF STREPTOKINASE AND TISSUE-PLASMINOGEN ACTIVATOR FOR OCCLUDED CORONARY-ARTERIES (GUSTO-I) TRIAL

Objectives. The purpose of this study was to examine the clinical impl ications of administering thrombolytic therapy to menstruating women w ith acute myocardial infarction. Background. Although anecdotal case r eports have suggested that thrombolytic therapy is safe during menstru ation, the risk of increased bleeding in menstruating women receiving such therapy is poorly defined. Methods. We identified menstruating wo men who received thrombolytic therapy by soliciting information on all North American women enrolled in the GUSTO-I trial and then collected additional information about them,vith use of a one-page data form. W e compared the characteristics and outcomes of these women with other GUSTO-I patient populations, including all North American women below the median age of menopause, all women and all patients. Results. The median age of the 12 menstruating women was 46 years; 75% were cigaret te smokers. The median hospital stay was 7 days, 2 fewer than the over all stay in GUSTO-I. None of these women died or had a stroke or sever e bleeding. Three patients (25%) had moderate bleeding (vaginal in two patients [66%]) that required transfusion compared with 11% of all GU STO-I patients and all North American premenopausal women (p = 0.13) a nd 17% of all female GUSTO I patients (p = 0.47). Because of the small sample size of 12 women, the power was low (0.37) to detect the obser ved difference in moderate bleeding. The median nadir hematocrit was 3 3% in the menstruating women compared with 34% in the premenopausal wo men and all women. The median time from symptom onset to treatment for the 12 women was 3.7 h, which was 0.9 h longer than the overall media n in the trial (p 0.09). Conclusions. Although there was no statistica lly significant increase in bleeding risk during menstruation, this fa ct may be a result of low statistical power rather than a lack of effe ct. Thus, the results suggest that there may be a clinically significa nt increase in the risk of moderate bleeding. Nevertheless, the GUSTO- I experience is consistent with the concept that the lifesaving benefi t of thrombolytic therapy for acute myocardial infarction should gener ally not be withheld because of active menstruation. (J Am Coil Cardio l 1995;26:1651-6)