RELATION BETWEEN INJECTIONS BEFORE 90-MINUTE ANGIOGRAPHY AND CORONARYPATENCY - RESULTS OF THE THROMBOLYSIS IN MYOCARDIAL-INFARCTION 4-TRIAL

The current goal of thrombolytic therapy is to achieve both full (Thro mbolysis in Myocardial Infarction [TIMI] grade 3) and early reperfusio n. Newer reperfusion strategies may now achieve a high degree of reper fusion even earlier than the traditional 90-minute end point, To deter mine whether injections before 90 minutes affect this traditional end point, the relation between the number of injections before 90-minute angiography and potency was examined in the TIMI 4 trial, The number o f injections before 90-minute angiography was no different between occ luded arteries (TIMI grade 0/1 flow) (2.46 +/- 1.78; n = 94) and paten t arteries (TIMI grade 2/3 few) (2.71 +/- 2.42; n = 295) (p = 0.24). T he incidence of any injections before 90 minutes was no different in p atent versus closed arteries (80.6% [77/98] vs 72.4% [22/304]; p = 0.1 0). The number of injections before 90 minutes was insignificantly sma ller in patients with TIMI grade 3 Flow (2.53 +/- 2.53 [n = 184] vs 2. 76 +/- 2.03 [n = 204]; p = 0.31), but the incidence of any injections before 90 minutes was significantly smaller in patients with TIMI grad e 3 flow (68.8% [132/192] vs 79.5% [167/210]; p = 0.01). No relation w as identified between the number of injections before 90-minute angiog raphy and patency at this traditional time point, This observation jus tifies the judicious use of a limited number of ''earlier snapshots'' of the infarct-related artery before 90 minutes to ascertain just how rapidly newer thrombolytic regimens achieve potency. Patients with TIM I grade 3 flow had a slightly lower incidence of injections before 90 minutes, perhaps because they did not require as urgent a definition o f coronary anatomy.