INVESTIGATIONS TO LOW-DOSE LOCO-REGIONAL THROMBOLYSIS OF ISOLATED THROMBOSES OF THE LEG WITH ACTILYSE(R) (RT-PA) - PART I - THE EFFECTIVITYOF THE THROMBOLYSIS

We investigated the effect of different dosages of Actilyse(R) (rt-PA) , different infusion volume and different time of application during l oco-regional thrombolysis in the isolated venous thrombosis of the leg . In 45 patients rt-PA was applicated in a dosage of 2.5 mg/h via a ve in of the sicking foot. The volume of infusion varied between 12.5 ml/ h and 125 ml/h, the infusion time was 2, 4 and 2 x 4 h, respectively, per day: group A - 5 mg/50 ml/2 h, group B - 10 mg/100 ml/4 h, group C - 10 mg/500 ml/4 h, group D - 10 mg/250 ml/4 h, group E - 10 mg/50 ml /4 h, The number of patients in each group was between 6 and 10, Hepar in was applicated simultaneously and continuously in a dose effecting the PTT. A control group obtained heparin only in an equal dose. A phl ebography took place before and after 4 to 5 cycles of lysis, The eval uation was carried out by means of the scores from Arnesen and Marder, respectively, The two scores showed a good correlation, In the follow ing evaluation the results of lysis were divided into 4 groups: 1., su bstantial lysis: improvement >50%, 2, moderate lysis: improvement betw een 10 and 50%, 3., no lysis: improvement between ii and 10%, 4, deter ioration: increase of score. All groups given rt-PA showed a better re sult than those given heparin only, The dose-groups D and E showed sig nificant better results than group A-C, while group E with 60% substan tial lysis was better than group D, but not significantly different. T here were only differences in trend in the groups D and E without stat istical significance between the result in the crural, popliteal and f emoral region. The time of anamnesis, number of lysis-cycles, rt-PA-do se related to body mass and sex had now statistical influence to the e ffect of lysis. The cumulated general dose was the highest in the dose groups D and E, It was differently between all groups, In one case (= 2.2%) the lysis was interrupted because of an anaphylactic reaction. There were 2 major bleedings (= 4.4%) and minor bleddings in three cas es (= 6.6%), The loco-regional lysis of isolated venous thromboses of the legs should be carried out with at least 20 mg rt-PA at day over a minimum application time of 8 h, The infusion volume had no significa nt influence to our results, More investigations are necessary.