Objective To evaluate the efficacy of recombinant human TNK tissue-type plasminogen activator and adenosine injection through guiding in treating acute ST-segment elevation myocardial infarction(ASTEMI)in emergency primary percutaneous coronary intervention(PPCI).Methods Patients with ASTEMI who chose to receive emergency PPCI were randomly divided into control group and treatment group according to a digital random table method.The control group received conventional treatment of PPCI.If the infarct-related artery(IRA)reached TIMI flow grade 3 after PPCI,the operation was terminated.If TIMI flow was ≤2,then a guide catheter to inject sodium nitroprusside,nitroglycerin,and tirofiban into the coronary artery to improve coronary microcirculation dysfunction(CMD)was applied until the IRA reached TIMI flow grade 3.The treatment group received the conventional treatment of PPCI,and after opening of the IRA during the operation,a guide catheter to inject recombinant human TNK tissue-type plasminogen activator(8 mg)and adenosine(200 pg)into the coronary artery was applied.If the IRA reached TIMI flow grade 3,the operation was terminated.If TIMI flow was ≤2,then adenosine injection was re-applied to improve CMD until the IRA reached TIMI flow grade 3.Observation indicators were as follows:① myocardial injury indicators:cardiac troponin Ⅰ(cTnⅠ),creatine kinase isoenzyme(CK-MB),and N-Terminal pro-brain natriuretic peptide(NT-pro BNP)levels before and 12 h,24 h,36 h,and 48 h after surgery;② myocardial perfusion indicators:corrected TIMI frame count(CTFC)after surgery and ST segment regression value(STR)at 90 min after surgery;③ degree of myocardial ischemia:rest D-SPECT+adenosine stress D-SPECT examination at day 3 after surgery,observation of myocardial perfusion total score under 17 segment distribution and myocardial ischemia total segment number;@adverse drug reactions at day 30 after surgery:subcutaneous ecchymosis,gingival bleeding,gastrointestinal bleeding,urinary bleeding,hemoglobin decline,and cerebral hemorrhage;⑤ major adverse cardiovascular events(MACE)at day 30 after surgery:cardiac death,myocardial infarction,heart failure,and target vessel revascularization.Results ① Myocardial injury indicators:There was no significant difference in the levels of cTnⅠ,CK-MB,or NT-pro BNP before surgery between the two groups(all P＞0.05).The myocardial injury indicators were significantly lower in the treatment group than in the control group at 12 hours after surgery(all P＜0.05),and then showed a downward trend.There was no significant difference between the two groups at 48 hours after surgery(all P＞0.05).② Myocardial perfusion indicators:CTFC in the treatment group was significantly better than that in the control group after surgery(P＜0.05).Using the rank sum test,the STR was significantly better in the treatment group than in the control group at 90 minutes after surgery(Z=2.437,P=0.014).③ myocardial ischemia:Both groups underwent rest D-SPECT+adenosine stress D-SPECT examination at 3 days after surgery.Under the distribution of 17 myocardial segments,the total score of myocardial perfusion and the total number of myocardial ischemia segments in the treatment group were significantly better than those in the control group(all P＜0.05).④ Adverse drug reactions 30 days after surgery:There was no significant difference in subcutaneous ecchymosis,gingival bleeding,gastrointestinal bleeding,urinary system bleeding,hemoglobin decline,or cerebral hemorrhage between the two groups(P＞0.05).⑤ MACE 30 days after surgery:There was no significant difference in cardiac death,myocardial infarction,heart failure,target vessel revascularization,or total MACE between the two groups(P＞0.05).Conclusion The intra-coronary injection of recombinant human TNK tissue-type plasminogen activator and adenosine injection through a guiding catheter in emergency PPCI is safe and effective for the treatment of ASTEMI.It can improve myocardial injury,myocardial perfusion,and myocardial ischemia.

[Objective] To explore the safety and effectiveness of provisional stenting (PS) applied in patients with unprotected simple left main bifurcation lesions, and to observe the impact of this procedure on cardiac function, myocardial injury, and myocardial perfusion. [Methods] A retrospective analysis was made on 82 patients with unprotected simple left main bifurcation lesions who underwent elective stenting and completed a 3-month follow-up in the Department of Cardiology, Hebei Medical University First Hospital. All the patients underwent preoperative examinations, including rest dynamic single-photon emission computed tomography (D-SPECT) and regadenoson stress D-SPECT before and 3 months after surgery. The safety evaluation indicators for the surgery included immediate success rate of stent implantation, acute stent thrombosis, coronary no-reflow, branch involvement, branch acute occlusion, acute left heart failure, heart block, cardiac tamponade, major bleeding, and mortality. The effectiveness evaluation indicators included the minimum lumen area (MLA) of the left main trunk of coronary artery measured by intravenous ultrasound (IVUS) before and after surgery, as well as cardiac function indicators [brain natriuretic peptide (BNP), left ventricular ejection fraction (LVEF), left ventricular end diastolic diameter (LVEDD)] and myocardial injury indicators [creatine kinase isoenzyme-MB (CK-MB), cardiac troponin Ⅰ (cTn Ⅰ)] at day 1, day 7, 1 month, and 3 months before and after surgery. The myocardial perfusion evaluation indicators included the total myocardial perfusion score and total ischemic segment number under the 17-segment distribution of myocardial perfusion using rest D-SPECT and regadenoson stress D-SPECT before and 3 months after surgery. [Results] Safety indicators: immediate success rate of stent implantation (100%), 19 cases (23.1%) of circumflex branch involvement that underwent balloon anastomosis dilation, 1 case of acute branch occlusion, followed by double stent surgery using provisional stenting-T stenting (PS-T) technique. There were no cases of acute stent thrombosis, coronary reflow, acute left heart failure, cardiac block, cardiac tamponade, major bleeding, or death. Effectiveness indicators: the MLA of the left main trunk measured by postoperative IVUS showed significant improvement compared to the preoperative. BNP, CK-MB, and cTnⅠ showed significant improvement from day 7 after surgery compared to before. Myocardial perfusion indicators: the total score of myocardial perfusion and the total number of ischemic segments in the 17-segment distribution of the myocardium after 3 months of surgery were significantly better than before. [Conclusion] PS can improve heart function, myocardial injury, and myocardial perfusion in patients with unprotected simple left main bifurcation lesions.