Usefulness of local delivery of thrombolytics before thrombectomy in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention (the delivery of thrombolytics before thrombectomy in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention [DISSOLUTION] randomized trial).

Thrombus aspiration during percutaneous coronary intervention can result in improved rates of normal epicardial flow and myocardial perfusion, but several unmet needs remain. The purpose of the Delivery of thrombolytIcs before thrombectomy in patientS with ST-segment elevatiOn myocardiaL infarction Undergoing primary percuTaneous coronary interventION (DISSOLUTION) trial was to evaluate the hypothesis that local delivery of thrombolytics can enhance the efficacy of thrombus aspiration in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention. A total of 102 patients with ST-segment elevation myocardial infarction and angiographic evidence of massive thrombosis in the culprit artery were randomly assigned to receive a local, intrathrombus bolus of 200,000 U of urokinase (n = 51) or saline solution (n = 51) by way of an infusion microcatheter, followed by manual aspiration thrombectomy. The end points included the final Thrombolysis In Myocardial Infarction flow grade and frame count, myocardial blush grade, 60-minute ST-segment resolution >70%, and major adverse cardiac and cerebrovascular events, defined as the death, reinfarction, stroke, or clinically driven target vessel revascularization at 6 months. The use of intrathrombus urokinase was associated with a significantly higher incidence of Thrombolysis In Myocardial Infarction flow grade 3 (90% vs 66%, p = 0.008) and lower postpercutaneous coronary intervention Thrombolysis In Myocardial Infarction frame count (19 ± 15 vs 25 ± 17, p = 0.033). The postprocedural myocardial perfusion was significantly increased with the use of urokinase (myocardial blush grade 2 or 3, 68% vs 45%, p = 0.028), with more patients showing ST-segment resolution >70% (82% vs 55%, p = 0.006). At 6 months of follow-up, the patients treated with intrathrombus urokinase showed a better major adverse cardiac event-free survival (6% vs 21%; log-rank p = 0.044). In conclusion, local, intrathrombus delivery of thrombolytics before manual thrombectomy improved the postprocedural coronary flow and myocardial perfusion and the 6-month clinical outcomes.