Long-term prognosis of late spontaneous reperfusion after failed thrombolysis for acute myocardial infarction

Background: Early reperfusion improves left ventricular (LV) function and s urvival after acute myocardial infarction (MI). Thrombolytic therapy achiev es early patency of the infarct artery in about two-thirds of patients. In nearly half of the remaining patients, in whom early reperfusion was not ac hieved with thrombolytic therapy, the infarct artery might reopen by the ti me of predischarge angiography. However, the impact of such late spontaneou s reperfusion after failed thrombolytic therapy on LV function and long-ter m survival remained unclear. Hypothesis: This study was undertaken to assess implication of late spontan eous reperfusion after failed thrombolytic therapy on LV function and long- term survival after acute MT. Methods: The study consisted of 198 patients with anterior acute MI who und erwent thrombolytic therapy and predischarge angiography: 160 patients with infarct artery patent early and late after therapy (persistent patency), 1 7 patients with infarct artery occluded early after therapy but patent at p redischarge angiography (late spontaneous reperfusion), and 21 patients wit h infarct artery occluded early and late after therapy (persistent occlusio n). Results: Persistent patency was associated with enhanced improvement in LV ejection fraction (7.7 +/- 11.8%) compared with late spontaneous reperfusio n (0.0 +/- 9.6%, p = 0.03) and persistent occlusion (-1.4 +/- 9.7%, p = 0.0 03). persistent patency was associated with better long-term survival than with late spontaneous reperfusion (p < 0.001) and persistent occlusion (p < 0.001). Multivariate analysis comparing persistent patency and late sponta neous reperfusion showed that early reperfusion was an independent predicto r of long-term survival. Conclusion: Late spontaneous reperfusion after failed thrombolytic therapy was associated with poor LV function and long-term survival, emphasizing th e importance of early reperfusion.