RELATION OF DURATION OF SYMPTOMS WITH RESPONSE TO THROMBOLYTIC THERAPY IN PULMONARY-EMBOLISM

Five previous trials of pulmonary embolism (PE) thrombolysis showed in dividually that duration of symptoms did not affect lung scan reperfus ion or angiographic clot lysis. We conducted an overview of 308 patien ts from these trials. Using 262 pairs of pre- and postlysis lung scans and 222 pairs of angiograms, we evaluated the relation between durati on of PE symptoms and changes in reperfusion and/or clot lysis followi ng thrombolysis. When comparing baseline and 24-hour post-thrombolysis lung scans, 77% of patients overall demonstrated improvement, includi ng 69% who were treated 6 to 14 days after onset of symptoms. We detec ted an inverse relation between duration of symptoms and improvement o n post-treatment lung scan reperfusion scores. For each additional day of symptoms before PE thrombolysis, there was a decrement of 0.8% of lung tissue reperfusion on lung scanning (95% confidence interval [CI] , 0.2% to 1.4%, p = 0.008), Adjustment for age and baseline lung scan defect had little effect on the results. Similarly, on angiography, le ss clot lysis immediately following thrombolysis was observed in the g roup of patients with the longest duration of symptoms compared with t hose with the shortest symptom duration (mean = 1.0 score unit of angi ographic improvement in those with symptoms for greater than or equal to 6 days vs 1.7 score units for less than or equal to 1 day of sympto ms, p = 0.03), This inverse relation between duration of symptoms and response to thrombolysis indicates that thrombolytic treatment should commence as soon as possible after PE is diagnosed, However, thromboly sis is still useful in patients who have had symptoms for 6 to 14 days , (C) 1997 by Excerpta Medica Inc.