Direct stenting after thrombus removal before primary angioplasty in acute myocardial infarction

Objectives: To verify whether direct stenting (DS) after thrombus removal during primary angioplasty (PPCI) in patients with ST-elevation acute myocardial infarction (STEMI) can improve myocardial reperfusion and prevent distal embolization compared to conventional stent implantation.
Background: Both mechanical removal and DS reduce thrombus dislodgment and improve microcirculatory reperfusion during PPCI. However, the additional effect of DS after thrombus removal has not been definitely assessed.
Methods: The DEAR-MI study included 148 consecutive STEMI patients who were randomly assigned to undergo or not thrombus aspiration before PPCI. For the purpose of the present study, we interrogated the DEAR-MI data bank to compare the occurrence of complete (>70%) ST-segment resolution (STR), myocardial blush grade (MBG)-3, no-reflow, and angiographic embolization in patients treated and untreated with DS.
Results: Clinical and angiographic characteristics were similar in the two groups. Comparing DS and no-DS groups, complete STR was found in 67% versus 51% (P = 0.08), MBG-3 in 86% versus 49% (P < 0.001), no-reflow in 1% versus14% (P < 0.01), angiographic embolization in 3% versus 19% (P < 0.01), TIMI flow-3 in 89% versus 70% (P < 0.01), and the corrected TIMI frame count was 16.2 versus 18.8 (P < 0.05). Among patients undergoing thrombus aspiration, the odds ratio of DS for MBG-3 and distal embolization was 4 (95% CI 1–16.6) and 0.10 (95% CI 0.01–0.93), respectively.
At multivariable analysis, thrombus aspiration (P < 0.001) and DS (P < 0.05) independently predicted MBG-3, while thrombus aspiration was the only independent predictor of DS.
Conclusions: DS during PPCI reduces distal embolization and improves myocardial reperfusion. This effect is significantly more relevant after thrombus aspiration.     

血栓抽吸联合冠状动脉内注射替罗非班对急性ST段抬高型心肌梗死患者的疗效观察

目的 观察冠脉内注射替罗非班联合血栓抽吸在急性ST段抬高型心肌梗死(STEMI)患者中的疗效。方法 选择2009年~2012年诊断为STEMI接受直接经皮冠状动脉介入(PCI)治疗的240例患者,随机分为直接PCI组、冠脉内注射替罗非班组（替罗非班组）、血栓抽吸组和血栓抽吸联合冠脉内注射替罗非班组（联合治疗组)。观察4组术后冠状动脉TIMI血流分级、心肌染色分级、术后24 h ST段回落>70%比率,术后6个月的主要复合终点事件。结果 与直接PCI组相比,血栓抽吸组、联合治疗组TIMI血流分级增加（P<0.05,P<0.01）;替罗非班组、联合治疗组心肌染色增加(均P<0.05);血栓抽吸组、联合治疗组ST段回落>70%比率增加(P<0.05,P<0.01);替罗非班组不降低患者6个月主要复合终点事件,血栓抽吸组降低患者6个月主要复合终点事件。但是,与替罗非班组或血栓抽吸组相比,联合治疗组在TIMI血流分级、心肌染色分级、术后24 h ST段回落>70%比率、6个月主要复合终点事件均未改善;4组间出血事件无显著差异。结论 血栓抽吸能改善急性ST段抬高型心肌梗死患者心肌灌注及降低6个月主要复合终点事件。     

机械与手动血栓抽吸在急诊经皮冠状动脉介入治疗中应用的随机对照研究

目的:比较机械与手动血栓抽吸在急性ST段抬高型心肌梗死(STEMI)直接经皮冠状动脉介入治疗(PPCI)中应用的临床疗效。方法:124例STEMI患者在接受PPCI治疗支架置入前,随机分为机械血栓抽吸组(AngioJet组,66例)和手动血栓抽吸组(Export组,58例)。主要终点是术后30 min时ST段回落(STR)≥50%比例及术后3个月内主要不良心脏事件(MACE)发生率,其他替代终点包括血栓抽吸术后TIMI血流分级、校正TIMI帧数(cTFC)、TIMI心肌灌注染色分级(MBG)、肌酸激酶同工酶(CK-MB)质量峰值时间、肌钙蛋白Ⅰ(cTnI)峰值等,比较组间基线资料以及主要终点、替代终点的差别。结果:术后30 min时STR≥50%比例在AngioJet组显著高于Export组(81.8%vs 65.6%,P=0.038),AngioJet组MACE事件发生率与Export组比较无统计学差异(7.6%vs12.1%,P=0.398)。AngioJet组术后TIMI血流3级比例显著高于Export组(86.4%vs 70.7%,P=0.032),cTFC、MBG、CK-MB质量峰值时间2组间无统计学差异。结论:对于急性心肌梗死血栓负荷重的完全闭塞病变的患者,直接支架置入术前采用AngioJet机械血栓清除相比手动抽吸导管清除血栓能取得更好的心肌灌注效果,但并不能改善术后3个月的临床结果。     

The extent of microvascular damage during myocardial contrast echocardiography is superior to other known indexes of post-infarct reperfusion in predicting left ventricular remodeling: results of the multicenter AMICI study.

OBJECTIVES: We sought to evaluate the value of the extent of microvascular damage as assessed with myocardial contrast echocardiography (MCE) in the prediction of left ventricular (LV) remodeling after ST-segment elevation myocardial infarction (STEMI) as compared with established clinical and angiographic parameters of reperfusion. BACKGROUND: Early identification of post-percutaneous coronary intervention microvascular dysfunction may help in tailoring appropriate pharmacological interventions in high-risk patients. The ideal method to establish effective microvascular reperfusion after percutaneous coronary intervention remains to be determined. METHODS: A total of 110 patients with first successfully reperfused STEMI were enrolled in the AMICI (Acute Myocardial Infarction Contrast Imaging) multicenter study. After reperfusion, peak creatine kinase, ST-segment reduction, and Thrombolysis In Myocardial Infarction (TIMI) and myocardial blush grade were calculated. We evaluated perfusion defects with MCE by using continuous infusion of Sonovue (Bracco, Milan, Italy) in real-time imaging. The endocardial length of contrast defect (CD) on day 1 after reperfusion was calculated. Wall motion score index, the extent of wall motion abnormalities, LV end-diastolic volume, and ejection fraction after reperfusion and at follow-up also were calculated. RESULTS: Of 110 patients, 25% evolved in LV remodeling and 75% did not. Although peak creatine kinase, ST-segment reduction >70%, and myocardial blush grade were not different between groups, in patients exhibiting LV remodeling, TIMI flow grade 3 was less frequent (p < 0.001), wall motion score index was greater (p < 0.001), and CD was greater (p < 0.001). At multivariate analysis, only TIMI flow grade <3 and CD with a cutoff of >25% were independently associated with LV remodeling. Among patients with TIMI flow grade 3, CD was the only independent variable associated with LV remodeling. CONCLUSIONS: Among patients with TIMI flow grade 3, the extent of microvascular damage, detected and quantitated by MCE, is the most powerful independent predictor of LV remodeling after STEMI as compared with persistent ST-segment elevation and myocardial blush grade.     

Myocardial reperfusion with tirofiban injection via aspiration catheter

There is no consensus on the use of thrombus aspiration (TA) in primary percutaneous coronary intervention (PPCI), and few studies have focused on the performance of tirofiban via TA catheter after PPCI. Our study investigated the clinical outcome of tirofiban injection through TA in acute ST-segment elevation myocardial infarction (STEMI) patients with large thrombus burden undergoing PPCI treatment. The study comprised 122 STEMI patients who underwent TA during PPCI. Participants were randomly divided into two groups. Group A received intravenous tirofiban injection and tirofiban injection via a TA catheter to the infarcted coronary artery after aspiration (n = 61). Group B received intravenous tirofiban injection only (n = 61). Baseline clinical information and follow-up data were collected for both groups. Coronary angiography, electrocardiography, and echocardiography findings as well as major adverse cardiovascular events (MACE) were recorded. There were significant differences in postprocedural Thrombolysis in Myocardial Infarction (TIMI) grade 2 and 3 flow between the two groups (p = 0.021, p = 0.006, respectively). The incidence of slow-flow in group A was significantly lower than that of group B (p = 0.011). An increased incidence of no ST-segment resolution was observed in group B (p = 0.011). There were fewer major adverse cardiovascular events in group A than in group B, but the difference was not statistically significant. Selective tirofiban injection via TA catheter during PPCI may improve myocardial reperfusion in STEMI patients with large thrombus burden.     

Thrombus aspiration with export catheter in ST elevation myocardial infarction

BACKGROUND: Many thrombectomy devices have failed to confirm initial promising results during primary angioplasty. This may be due to device complexity and operator experience. The objective of this study was to assess the safety and efficacy of the EXPORT catheter for thrombus aspiration in patients with ST elevation myocardial infarction (STEMI). METHODS: EXPORT catheter was used in patients with STEMI and angiographic evidence of thrombus in vessels with a reference diameter > or =1.5 mm. Direct stenting and glycoprotein IIb/IIIa inhibitors were liberally employed to optimize angiographic and clinical results. Epicardial and myocardial angiographic parameters, in-hospital major adverse cardiac events (MACE, i.e., cardiac death, myocardial infarction, target vessel revascularization) were assessed. RESULTS: EXPORT catheter was used in 129 patients without any device-related complications. Angiographic analysis following thrombus aspiration revealed a significant improvement in TIMI frame count (P = 0.0001), myocardial perfusion (P = 0.0001), TIMI thrombus grade (P = 0.0001), and TIMI flow (P = 0.0001). Stent implantation did not significantly improve myocardial perfusion, TIMI thrombus grade, or TIMI flow, but improved TIMI frame count, minimal lumen, and reference vessel diameter. When compared to a historical STEMI control group not undergoing thrombus aspiration, our EXPORT population showed significant improvements in reperfusion parameters. In-hospital MACE were uncommon (4.5%) despite high-risk patient characteristics. CONCLUSIONS: Our study demonstrates that routine use of EXPORT catheter in patients with STEMI and coronary thrombosis is feasible, safe, and associated with significant improvements in flow-related angiographic parameters. The relative simplicity of this approach makes it an attractive option in this challenging situation.     

Adjunct thrombus aspiration reduces mortality in patients undergoing percutaneous coronary intervention for ST-elevation myocardial infarction with high-risk angiographic characteristics

Routine aspiration thrombectomy (AT) in percutaneous coronary intervention for patients with ST-segment elevation myocardial infarction (STEMI) has not proved effective in randomized trials. However, in patients undergoing primary percutaneous coronary intervention with severely reduced flow or visible thrombus, AT remains an intuitively attractive option. The use of adjunctive AT in a high-risk cohort of 158 consecutive patients with STEMI and Thrombolysis In Myocardial Infarction (TIMI) 0 to 1 flow or visible thrombus on baseline angiography was examined. Of these, 80 patients underwent AT as an adjunct to primary percutaneous coronary intervention, and 78 underwent percutaneous coronary intervention without AT (non-AT). TIMI 3 flow rates, residual thrombus after percutaneous coronary intervention, and major adverse cardiac events (mortality and nonfatal Q-wave myocardial infarction) at 30 days, 6 months, and 1 year were compared. Baseline characteristics were similar between groups. The AT group more frequently achieved TIMI 3 flow after the intervention (91.3% AT vs 67.9% non-AT; p <0.001) and had less residual thrombus (7.5% AT vs 19.2% non-AT; p = 0.03). AT was associated with reduced major adverse cardiac events at 6 months (6.8% AT vs 24.0% non-AT; p = 0.004) and 1 year (16.6% AT vs 29.2% non-AT; p = 0.009), and decreased mortality rates in the AT group at 6 months (5.4% AT vs 21.3% non-AT; p = 0.004) and 1 year (7.7% AT vs 26.2% non-AT; p = 0.005). In conclusion, for patients with STEMI and TIMI 0 or 1 flow or visible thrombus on baseline angiography, AT was associated with increased TIMI 3 flow rates, decreased residual thrombus, and decreased clinical events, including mortality.     

Prophylactic use of manual thrombectomy in ST-segment elevation myocardial infarction

ObjectiveWe sought to evaluate the effects of manual thrombectomy on myocardial reperfusion performed during percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI).BackgroundComplete reperfusion after primary PCI is compromised by the presence of intraluminal thrombus. Thus effective and safe extraction of thrombus in a timely fashion is important for successful reperfusion.MethodsThirty-two patients (age 51±12 years, males 78%) with STEMI and angiographic evidence of intraluminal thrombus underwent thrombectomy during an 18-month period. Thrombectomy was performed after the presence of thrombus was confirmed angiographically by the operator either before or after primary angioplasty. Thrombectomy was performed using the 6F Export Aspiration Catheter (Medtronic Corporation, Santa Rosa, CA, USA). Myocardial reperfusion using Thrombolysis in Myocardial Infarction (TIMI) flow and myocardial blush grade was assessed by two independent observers.ResultsThe infarct-related artery was left anterior descending (59%), right coronary artery (19%), saphenous venous graft (19%), or left circumflex artery (3%). The coronary lesion was Type B in 62% and Type C in 37% patients, with an average length of 18.2+4.6 mm and reference vessel diameter of 3.2±0.4 mm. The preprocedural TIMI flow was 0 in 62%, 1 in 12%, 2 in 22%, and 3 in 3% of patients. The postprocedural TIMI flow was 0 in 3%, 1 in 6%, 2 in 25%, and 3 in 56% of patients. The postprocedural myocardial blush grade was 0 in 6%, 1 in 9%, 2 in 35%, and 3 in 48% of patients. The in-hospital mortality was 0 and the 30-day mortality was 3%.ConclusionManual thrombectomy using an Export catheter is safe and effective in establishing myocardial reperfusion after STEMI.     

Intracoronary thrombectomy with the export aspiration catheter before angioplasty in patients with ST-segment elevation myocardial infarction

OBJECTIVE: We aimed to assess the safety and feasibility of thrombectomy with the Export Aspiration Catheter (EAC) before angioplasty, and its ability to improve angiographic results in patients with ST-segment elevation myocardial infarction (STEMI). BACKGROUND: Distal embolization of atherothrombotic material often occurs during angioplasty in STEMI, compromising optimal myocardial reperfusion. METHODS: We performed a thrombus-aspiration with EAC prior to angioplasty in 64 consecutive patients with STEMI. Successful thrombectomy was defined as an improvement of TIMI flow grade >or=1. RESULTS: Successful thrombectomy (increase of TIMI flow >or=1) was achieved in 40 patients (62.5%). Mean TIMI flow grade increased from 0.7 +/- 1 to 1.9 +/- 1.2 (p < 0.0001) after thrombectomy. TIMI flow grade 3 was observed more frequently after EAC compared with guidewire alone (51.5% vs. 9%, p = 0.0062). Direct stenting was performed in most of the patients (n = 41, 64%). Distal embolization and no reflow/slow flow phenomenon occurred in 8 patients (12.5%). No vessel injury after EAC thrombectomy was reported. After treatment with balloon angioplasty and/or stenting, final TIMI flow grade 3 was achieved in 54 patients (84.5%). By multivariate analysis, ischemic time < 6 hours was a significant independent predictor of successful thrombectomy (p = 0.0437). CONCLUSIONS: Our series suggests that EAC thrombectomy prior to angioplasty in the setting of STEMI is safe and feasible. It might reduce the culprit coronary lesion's thrombus burden, leading to improved flow restoration and myocardial reperfusion. Further large randomized studies are warranted to confirm these preliminary results and to assess the impact of thrombus-aspiration on infarct size as well as on clinical outcomes.     

Rheolytic thrombectomy with percutaneous coronary intervention for infarct size reduction in acute myocardial infarction: 30-day results from a multicenter randomized study.

OBJECTIVES: The goal of this work was to determine whether rheolytic thrombectomy (RT) as an adjunct to primary percutaneous coronary intervention (PCI) reduces infarction size and improves myocardial perfusion during treatment of ST-segment elevation myocardial infarction (STEMI). BACKGROUND: Primary PCI for STEMI achieves brisk epicardial flow in most patients, but myocardial perfusion often remains suboptimal. Distal embolization of thrombus during treatment may be a contributing factor. METHODS: This prospective, multicenter trial enrolled 480 patients presenting within 12 h of symptom onset and randomized to treatment with RT as an adjunct to PCI (n = 240) or to PCI alone (n = 240). Visible thrombus was not required. The primary end point was infarct size measured by sestamibi imaging at 14 to 28 days. Secondary end points included final Thrombolysis In Myocardial Infarction (TIMI) flow grade, tissue myocardial perfusion (TMP) blush, ST-segment resolution, and major adverse cardiac events (MACE), defined as the occurrence of death, new Q-wave myocardial infarction, emergent coronary artery bypass grafting, target lesion revascularization, stroke, or stent thrombosis at 30 days. RESULTS: Final infarct size was higher in the adjunct RT group compared with PCI alone (9.8 +/- 10.9% vs. 12.5 +/- 12.13%; p = 0.03). Final TIMI flow grade 3 was lower in the adjunct RT group (91.8% vs. 97.0% in the PCI alone group; p < 0.02), although fewer patients had baseline TIMI flow grade 3 in the adjunct RT group (44% vs. 63% in the PCI alone group; p < 0.05). There were no significant differences in TMP blush scores or ST-segment resolution. Thirty-day MACE was higher in the adjunct RT group (6.7% vs. 1.7% in the PCI alone group; p = 0.01), a difference primarily driven by very low mortality rate in patients treated with PCI alone (0.8% vs. 4.6% in patients treated with adjunct RT; p = 0.02). CONCLUSIONS: Despite effective thrombus removal, RT with primary PCI did not reduce infarct size or improve TIMI flow grade, TMP blush, ST-segment resolution, or 30-day MACE.     

X-sizer for thrombectomy in acute myocardial infarction improves ST-segment resolution: results of the X-sizer in AMI for negligible embolization and optimal ST resolution (X AMINE ST) trial

OBJECTIVES: We sought to compare, in a prospective randomized multicenter study, the effect of adjunctive thrombectomy using X-Sizer (eV3, White Bear Lake, Minnesota) before percutaneous coronary intervention (PCI) versus conventional PCI in patients with acute myocardial infarction (AMI) for <12 h and Thrombolysis In Myocardial Infarction (TIMI) flow grade 0 to 1. The primary end point was the magnitude of ST-segment resolution after PCI. BACKGROUND: Despite a high rate of TIMI flow grade 3 achieved by PCI in patients with AMI, myocardial reperfusion remains relatively low. Distal embolization of thrombotic materials may play a major role in this setting. METHODS: We conducted a prospective, randomized, multicenter study in patients with AMI <12 h and initial TIMI flow grade 0 to 1 who were treated with primary PCI. The magnitude of ST-segment resolution 1 h after PCI was the primary end point. RESULTS: A total of 201 patients were included. Treatment groups were comparable by age (61 +/- 13 years), diabetes (22%), previous MI (8%), anterior MI (52%), onset-to-angiogram (258 +/- 173 min), and glycoprotein IIb/IIIa inhibitor use (59%). The magnitude of ST-segment resolution was greater in the X-Sizer group compared with the conventional group (7.5 vs. 4.9 mm, respectively; p = 0.033) as ST-segment resolution >50% (68% vs. 53%; p = 0.037). The occurrence of distal embolization was reduced (2% vs. 10%; p = 0.033) and TIMI flow grade 3 was obtained in 96% vs. 89%, respectively (p = 0.105). Myocardial blush grade 3 was similar (30% vs. 31%; p = NS). Six-month clinical outcome was comparable (death, 6% vs. 4% and major adverse cardiac and cerebral events, 13% vs. 13%, respectively). By multivariate analysis, independent predictors of ST-segment resolution >50% were: younger age, non-anterior MI, use of the X-Sizer, and a short time interval from symptom onset. CONCLUSIONS: Reducing thrombus burden with X-Sizer before stenting leads to better myocardial reperfusion, as illustrated by a reduced risk of distal embolization and better ST-segment resolution.     

Hyperglycemia is an important predictor of impaired coronary flow before reperfusion therapy in ST-segment elevation myocardial infarction

OBJECTIVES: This study was designed to investigate whether elevated glucose is associated with impaired Thrombolysis In Myocardial Infarction (TIMI) flow before primary percutaneous coronary intervention (PCI). BACKGROUND: Reperfusion before primary PCI in patients with ST-segment elevation myocardial infarction (STEMI) is associated with an improved outcome. Hyperglycemia in patients with STEMI is associated with an adverse prognosis. Hyperglycemia may induce a pro-thrombotic state and therefore be of influence on TIMI flow before PCI. METHODS: A total of 460 consecutive patients with STEMI treated with primary PCI were included in this analysis. Hyperglycemia was defined as a glucose > or =7.8 mmol/l (140 mg/dl). RESULTS: Hyperglycemia was observed in 70% and TIMI flow grade 3 before primary PCI in 17% of the patients. Patients with hyperglycemia less often had TIMI flow grade 3 before primary PCI (12% vs. 28%, p < 0.001). After adjustment for differences in baseline variables, hyperglycemia was a strong predictor of absence of reperfusion before primary PCI (odds ratio 2.6, 95% confidence interval 1.5 to 4.5). CONCLUSIONS: Hyperglycemia in patients with STEMI is an important predictor of impaired epicardial flow before reperfusion therapy has been initiated. Investigation of methods improving coronary flow before primary PCI in these patients is warranted.     

Performance of the thrombolysis in myocardial infarction risk index in the National Registry of Myocardial Infarction-3 and -4: a simple index that predicts mortality in ST-segment elevation myocardial infarction

OBJECTIVES: We sought to evaluate a simple risk index based on age and vital signs in a community sample of patients with ST-segment elevation myocardial infarction (STEMI). BACKGROUND: A simple risk index based on age and vital signs (heart rate x [age/10](2)/systolic blood pressure) developed from patients with STEMI accurately predicts mortality in clinical trials of fibrinolysis. The application of such a tool in an unselected population is necessary to evaluate its utility in clinical practice. METHODS: To evaluate the Thrombolysis In Myocardial Infarction (TIMI) risk index for routine practice, we tested it in the National Registry of Myocardial Infarction (NRMI)-3 and -4. The risk index was evaluated as a continuous variable in patients with STEMI from NRMI and in subgroups based on age and reperfusion status. RESULTS: A total of 153,486 patients with STEMI were eligible. As anticipated, STEMI patients in NRMI had a higher risk index profile, as compared with those in the clinical trial (median 26.9 vs. 20, p < 0.0001). Classification of NRMI patients with STEMI into risk groups revealed a significant graded relationship with mortality (0.9% to53.2%, p(trend) < 0.0001, c statistic 0.79). The discriminatory capacity of the risk index was particularly strong in the 81,679 patients receiving reperfusion therapy (0.6% to60%, p(trend) < 0.0001, c statistic 0.81). For the 71,807 patients not receiving reperfusion therapy, a strong graded relationship remained (1.9% to 52.2%, p(trend) < 0.0001, c statistic 0.71). Among the elderly, although the distribution of scores was shifted toward higher risk, the performance remained (0% to 53.1%, p(trend)< 0.0001, c statistic 0.71). CONCLUSIONS: A simple risk index from baseline clinical variables routinely obtained at the first patient encounter predicted mortality in a large unselected heterogeneous group of patients with STEMI.     

Prognostic implications of TIMI flow grade in the infarct related artery compared with continuous 12-lead ST-segment resolution analysis. Reexamining the "gold standard" for myocardial reperfusion assessment

OBJECTIVE: To compare the prognostic significance of reperfusion assessment by Thrombolysis in Myocardial Infarction (TIMI) flow grade in the infarct related artery and ST-segment resolution analysis, by correlating with clinical outcomes in patients with acute myocardial infarction (AMI). BACKGROUND: Angiographic assessment, based on epicardial coronary anatomy, has been considered the "gold standard" for reperfusion. The electrocardiogram (ECG) monitoring provides a noninvasive, real-time physiologic marker of cellular reperfusion and may better predict clinical outcomes. METHODS: Two hundred fifty-eight AMI patients from the Thrombolytics and Myocardia Infarction phase 7 and Global Utilization of Streptokinase tPA for Occluded coronary arteries phase 1 trials were stratified based on blinded, simultaneous reperfusion assessment on the acute angiogram (divided into TIMI grades 0 & 1, TIMI grade 2 and TIMI grade 3) and ST-segment resolution analysis (divided into: <50% ST-segment elevation resolution or reelevation and > or =50% ST-segment elevation resolution). In-hospital mortality, congestive heart failure (CHF) and combined mortality or CHF were compared to determine the prognostic significance of reperfusion assessment by each modality using chi-square and Fisher's Exact tests for univariable correlation and logistic regression analysis for univariable and multivariable prediction models. RESULTS: By logistic regression analysis, ST-segment resolution patterns were an independent predictor of the combined outcome of mortality or CHF (p = 0.024), whereas TIMI flow grade was not (p = 0.693). Among the patients determined to have failed reperfusion by TIMI flow grade assessment (TIMI flow grade 0 & 1), the ST-segment resolution of > or =50% identified a subgroup with relatively benign outcomes with the incidence of the combined end point of mortality or CHF 17.2% versus 37.2% in those without ST-segment resolution (p = 0.06). CONCLUSION: Continuous 12-lead ECG monitoring can be an inexpensive and reliable modality for monitoring nutritive reperfusion status and to obtain prognostic information in patients with AMI.     

Effect of reactive hyperemia after coronary recanalization on myocardial tissue reperfusion by thrombolysis in myocardial infarction flow grade in acute myocardial infarction

Thrombolysis In Myocardial Infarction (TIMI) flow grade is widely used to evaluate myocardial tissue reperfusion in acute myocardial infarction (AMI), but the current grading system is incomplete. Therefore, we clarified the regulation of epicardial coronary flow velocity with the progression of microvascular dysfunction in AMI. We studied 36 patients with first anterior AMI. After intervention, we assessed TIMI flow grade and measured average peak velocity (APV) at baseline and after infusion of adenosine triphosphate (48 microg; baseline and hyperemic APVs, respectively) with a Doppler guidewire. We performed myocardial contrast echocardiography after 2 weeks to assess microvascular integrity (good reflow vs no reflow) and left ventriculography at admission and discharge (24 +/- 2 days) to measure regional wall motion (SD/chord). Patients were classified into 3 groups based on TIMI flow grade and microvascular integrity: TIMI grade 3 flow/good reflow (n = 16), TIMI grade 3 flow/no reflow (n = 12), and TIMI grade 2 flow (n = 8). Baseline APV was comparable in the patients with TIMI grade 3 flow but hyperemic APV was higher in patients with TIMI grade 3 flow/good reflow than in those with TIMI grade 3 flow/no reflow (hyperemic APV 59.3 +/- 25.8 vs 32.8 +/- 8.9 cm/s, p <0.01). All patients with TIMI grade 2 flow showed no reflow and the lowest values of baseline and hyperemic APVs. Regional wall motion at discharge was higher in patients with TIMI grade 3 flow/good reflow than in those with TIMI grade 3 flow/no reflow and TIMI grade 2 flow (-1.44 +/- 0.70, -2.69 +/- 0.31, and -2.88 +/- 0.48 SD/chord, respectively, p <0.01). In conclusion, compensatory reactive hyperemia preserves epicardial coronary flow velocity even in patients with microvascular damage, and with the progression of damage, this compensatory hyperemia can no longer preserve epicardial coronary flow velocity, and baseline APV is decreased in TIMI grade 2 flow.     

Relation between electrocardiographic ST-segment resolution and early and late outcomes after primary percutaneous coronary intervention for acute myocardial infarction

ST-segment resolution (STR) is a surrogate end point in reperfusion trials of acute myocardial infarction, but there are few data regarding the optimum methods of measurement, clinical predictors, and correlation with late cardiac mortality. Consecutive patients (n = 1,005) who had acute myocardial infarction and >/=2 mm ST-segment elevation controlled with primary percutaneous coronary intervention (PCI) constituted our study group. Follow-up was obtained in 97% of patients at a median of 6.2 years. STR measured as maximum ST-segment elevation after PCI provided better discrimination of late cardiac mortality than did STR measured as percent resolution. Complete STR (<1.0 mm ST-segment elevation after PCI) was achieved in only 42% of patients. Anterior infarction, Killip's class 3 to 4, and Thrombolysis In Myocardial Infarction flow grades <2 before PCI and <3 after PCI were strong independent predictors of partial or poor STR. STR (complete [<1.0 mm] vs partial [1.0 to 2.0 mm] vs poor [>2.0 mm]) correlated with in-hospital mortality (4.0% vs 6.7% vs 11.6%, p = 0.005), reinfarction (1.4% vs 3.4% vs 6.1%, p = 0.01), and late cardiac mortality (17% vs 25% vs 44%, p <0.0001). Correlation with late mortality was stronger for nonanterior than for anterior infarction. Poor STR was a strong independent predictor of late mortality (hazard ratio 1.63, 95% confidence interval 1.06 to 2.50, p = 0.028), even after adjusting for Thrombolysis In Myocardial Infarction flow. These data support the use of STR as a simple method to stratify patients by risk after primary PCI for acute myocardial infarction and support the use of STR as a surrogate end point in reperfusion trials of acute myocardial infarction.     

Manual thrombus-aspiration improves myocardial reperfusion: the randomized evaluation of the effect of mechanical reduction of distal embolization by thrombus-aspiration in primary and rescue angioplasty (REMEDIA) trial

OBJECTIVES: The aim of this study was to evaluate the use of a new manual thrombus-aspirating device in unselected patients with ST-segment elevation acute myocardial infarction (STEMI) undergoing urgent percutaneous coronary intervention (PCI). BACKGROUND: Failure to achieve myocardial reperfusion often occurs during PCI in patients with STEMI. The use of thrombus-aspirating devices might improve myocardial reperfusion by reducing distal embolization. METHODS: We prospectively randomized before coronary angiography 100 consecutive patients with STEMI to either standard PCI or PCI with manual thrombus-aspiration. Primary end points of the study were post-procedural rates of myocardial blush grade (MBG) > or =2 and ST-segment resolution (STR) > or =70%. Analyses were planned by intention to treat. RESULTS: Ninety-nine patients entered the analyses. The rates of post-procedural MBG > or =2 and STR > or =70% were, respectively, 68.0% and 44.9% in the thrombus-aspiration group compared with 58.0% and 36.7% in the standard PCI group: odds ratio (OR) 2.6 (95% confidence interval [CI] 1.2 to 5.9), p = 0.020, and 2.4 (95% CI 1.1 to 5.3), p = 0.034, respectively. Moreover, the rate of patients achieving both the angiographic and electrocardiographic (ECG) criteria of optimal reperfusion was significantly higher in the thrombus-aspiration group compared with standard PCI: 46.0% versus 24.5%, OR 2.6 (95% CI 1.1 to 6.2), p = 0.025. In multivariate analysis, randomization to thrombus-aspiration was a significant independent predictor of achievement of MBG > or =2 and STR > or =70% (p = 0.013). CONCLUSIONS: This prospective randomized study shows that manual thrombus-aspiration in unselected patients with STEMI undergoing primary or rescue PCI is clinically feasible and results in better angiographic and ECG myocardial reperfusion rates compared with those achieved by standard PCI.     

Predictive value of the index of microcirculatory resistance in patients with ST-segment elevation myocardial infarction.

OBJECTIVES: The objective of this study is to evaluate the predictive value of the index of microcirculatory resistance (IMR) in patients undergoing primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI). BACKGROUND: Despite adequate epicardial artery reperfusion, a number of patients with STEMI have a poor prognosis because of microvascular damage. Assessing the status of the microvasculature in this setting remains challenging. METHODS: In 29 patients after primary PCI for STEMI, IMR was measured with a pressure sensor/thermistor-tipped guidewire. The Thrombolysis In Myocardial Infarction (TIMI) myocardial perfusion grade, TIMI frame count, coronary flow reserve, and ST-segment resolution were also recorded. RESULTS: The IMR correlated significantly with the peak creatinine kinase (CK) (R = 0.61, p = 0.0005) while the other measures of microvascular dysfunction did not. In patients with an IMR greater than the median value of 32 U, the peak CK was significantly higher compared with those having values 32 U compared with 相似文献   

Comparison of angiographic and other findings and mortality in non-ST-segment elevation versus ST-segment elevation myocardial infarction in patients undergoing early invasive intervention

We sought to compare the angiographic findings and mortality in patients with non-ST-segment elevation (NSTEMI) versus ST-segment elevation myocardial infarction (STEMI) undergoing early invasive intervention. Of 11,872 patients enrolled in the Korean Acute Myocardial Infarction Registry from November 2005 to January 2008, we studied patients with NSTEMI undergoing early invasive intervention (n = 1,486) and those with STEMI undergoing primary percutaneous coronary intervention (n = 4,392). Multivessel coronary disease, baseline Thrombolysis In Myocardial Infarction (TIMI) flow grade 3, and the left circumflex artery as a culprit lesion occurred more frequently in patients with NSTEMI than in those with STEMI. Those with NSTEMI had a significantly lower mortality rate than those with STEMI during a median follow-up of about 12 months (3.8% vs 6.7%, p <0.001). In the patients with NSTEMI, the independent predictors of mortality included postprocedural TIMI flow grade 0 to 2 (hazard ratio [HR] 3.07, 95% confidence interval [CI] 1.01 to 9.29, p = 0.047) and multivessel coronary disease (HR 3.83, 95% CI 1.36 to 10.81, p = 0.010) but not baseline TIMI flow or infarct location. However, baseline TIMI flow grade 0 to 2 (HR 1.56, 95% CI 1.03 to 2.36, p = 0.035), anterior infarction (HR 1.69, 95% CI 1.28 to 2.23, p <0.001), multivessel coronary disease (HR 1.45, 95% CI 1.10 to 1.91, p = 0.008), and postprocedural TIMI flow grade 0 to 2 (HR 2.00, 95% CI 1.42 to 2.82, p <0.001) were all independent predictors of mortality in the patients with STEMI. In conclusion, the angiographic findings in patients from NSTEMI differ from those in patients with STEMI. Postprocedural TIMI flow and multivessel coronary disease were independent predictors of mortality in patients with NSTEMI undergoing early invasive intervention.     

Quantitative analysis of the impact of total ischemic time on myocardial perfusion and clinical outcome in patients with ST-elevation myocardial infarction

Early reperfusion of the infarct-related coronary artery is an important issue in improvement of outcomes after ST-segment elevation myocardial infarction (STEMI). In this study, the clinical significance of total ischemic time on myocardial reperfusion and clinical outcomes was evaluated in patients with STEMI treated with primary percutaneous coronary intervention and thrombus aspiration and additional triple-antiplatelet therapy. Total ischemic time was defined as time from symptom onset to first intracoronary therapy (first balloon inflation or thrombus aspiration). All patients with STEMI treated with primary percutaneous coronary intervention with total ischemic times ≥30 minutes and <24 hours from 2005 to 2008 were selected. Ischemic times were available in 1,383 patients, of whom 18.4% presented with total ischemic times ≤2 hours, 31.2% >2 to 3 hours, 26.8% >3 to 5 hours, and 23.5% >5 hours. Increased ischemic time was associated with age, female gender, hypertension, and diabetes. Patients with total ischemic times <5 hours more often had myocardial blush grade 3 (40% to 45% vs 22%, p <0.001) and complete ST-segment resolution (55% to 60% vs 42%, p = 0.002) than their counterparts with total ischemic times >5 hours. In addition, patients with total ischemic times ≤5 hours had lower 30-day mortality (1.5% vs 4.0%, p = 0.032) than patients with total ischemic times >5 hours. In conclusion, in this contemporary cohort of patients with STEMI treated with primary percutaneous coronary intervention, triple-antiplatelet therapy, and thrombus aspiration, short ischemic time was associated with better myocardial reperfusion and decreased mortality. After a 5-hour period in which outcomes remain relatively stable, myocardial reperfusion becomes suboptimal and mortality increases.