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.     

Microvascular dysfunction following primary percutaneous coronary intervention in the setting of ST-elevation myocardial infarction

Primary percutaneous coronary intervention (PCI) is an established reperfusion strategy in the treatment of acute myocardial infarction with ST-segment elevation (STEMI). Nevertheless, myocardial damage is not terminated immediately, even with successful primary PCI, which eliminates the epicardial occlusion. Despite the success of contemporary reperfusion therapy and effective restoration of epicardial coronary flow, many patients have suboptimal flow at the tissue level within the myocardium. Studies indicate that these patients have a decreased recovery of left ventricular function and poor long-term prognosis. This could be due to reperfusion injury, embolization of epicardial thrombus or plaque debris jeopardizing tissue-level perfusion. This article attempts to review the process of microvascular dysfunction following reperfusion of STEMI with primary PCI and different strategies tried thus far to improve this.     

The risks and benefits of drug-eluting stents in the setting of STEMI

Primary percutaneous coronary intervention (PCI) represents the treatment of choice in patients with ST-segment elevation myocardial infarction (STEMI). In randomized trials excluding STEMI patients, using drug-eluting stents (DES) significantly reduced angiographic restenosis and target vessel revascularization compared with bare metal stents (BMS); however, concerns exist regarding an increased follow-up incidence of stent thrombosis after DES implantation. This complication, which is associated with higher mortality and morbidity rates, may be more frequent among STEMI patients receiving DES versus BMS. Various registries, randomized trials, and two recent meta-analyses on patients undergoing primary PCI have shown that using DES is safe and is associated with significantly reduced rates of restenosis and repeat intervention without an increased risk of myocardial infarction or stent thrombosis at intermediate-term follow-up. However, large trials with hard clinical end points and longer follow-up are needed before routine DES use can be recommended in patients undergoing primary PCI.     

Ageing, impaired myocardial perfusion, and mortality in patients with ST-segment elevation myocardial infarction treated by primary angioplasty.

AIMS: It is still unknown whether impaired myocardial perfusion helps to explain the higher mortality observed with ageing in patients with ST-segment elevation myocardial infarction (STEMI) treated with primary angioplasty. METHODS AND RESULTS: In 1548 consecutive patients with STEMI treated with primary angioplasty, myocardial perfusion was evaluated by myocardial blush grade (MBG) and ST-segment resolution. All clinical and follow-up data were prospectively collected. Advanced age was associated with a significantly higher clinical and angiographic risk profile. We found a linear relationship between increasing age, decreased myocardial perfusion, and higher 1-year mortality. After adjustment for baseline potential confounding variables, increased age was still significantly associated with impaired myocardial blush (MBG 0-1) (P=0.028), and ST-segment resolution (<50%) (P=0.007). At multivariable analysis both age (P<0.0001) and poor myocardial perfusion (P<0.0001) were independent predictors of 1-year mortality. CONCLUSION: This study shows that impaired reperfusion is an additional determinant of the poor outcome observed with advanced age in patients with STEMI undergoing mechanical revascularization.     

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.     

Effect of impaired myocardial reperfusion on left ventricular remodeling in patients with anterior wall acute myocardial infarction treated with primary coronary intervention

We assessed the effect of impaired myocardial blush after primary coronary intervention (PCI) on left ventricular remodeling in patients with ST-segment elevation myocardial infarction (STEMI). The study population consisted of 145 patients with first anterior STEMI that was treated successfully (Thrombolysis In Myocardial Infarction grade 3 flow) with PCI. Left ventricular remodeling was defined as an increase of > or =20% in end-diastolic volume based on repeated echocardiographic measurements in patients. The study population was divided into 2 groups according to the presence (myocardial blush grade [MBG] 2 to 3, n = 86) or absence (MBG 0 to 1, n = 59) of myocardial reperfusion. Left ventricular remodeling appeared in 21% of the entire study group. Poor myocardial blush after PCI was associated with an increased rate of remodeling compared with good myocardial reperfusion (32% vs 14%, hazard ratio 2.308, 95% confidence interval [CI] 1.21 to 4.39, p=0.014). Symptoms of heart failure were observed significantly more often in patients with MBG 0 to 1 (35.6% vs 18.6%, p = 0.032) than in patients with MBG 2 to 3. In multivariate analysis, only age (odds ratio 0.96, 95% CI 0.92 to 0.99, p = 0.02) and MBG 0 to 1 (odds ratio 3.15, 95% CI 1.35 to 7.31, p = 0.008) were associated with left ventricular dilation. In conclusion, impaired microvascular reperfusion is associated with left ventricular remodeling and development of congestive heart failure in patients with anterior STEMI that is treated with primary coronary angioplasty.     

急性心肌梗死患者经皮冠状动脉介入治疗术后ST段回落不良的分析

目的探讨ST段抬高急性心肌梗死(AMI)患者直接PCI术后ST段回落不良的相关因素。方法173例符合ST段抬高AMI诊断并行直接PCI的患者,计算其心电图ST段回落指数,运用logistic回归分析影响ST段回落的相关因素。结果冠状动脉造影心肌呈色分级0/1(OR=2.936)、病变部位(OR=2.121)、胸痛开始到再灌注的时间(OR=1.314)、梗死前心绞痛(OR=1.053)是影响术后心电图ST段恢复的相关因素。结论AMI直接PCI术后心电图ST段恢复程度与上述因素有关。     

Clinical features of early myocardial rupture of acute myocardial infarction

We assessed the clinical features of patients with myocardial rupture within 48 to 72 hours, defined as early myocardial rupture, after percutaneous coronary intervention (PCI) for ST-segment elevation acute myocardial infarction (STEMI). Six patients (4 men, 66 ± 13 years) with early myocardial rupture were identified from 1252 consecutive patients undergoing PCI for STEMI. We evaluated the degree of microvascular reperfusion using thrombolysis in myocardial infarction (TIMI) myocardial perfusion (TMP) grade and a resolution of sum of ST-segment elevation in a 12-lead electrocardiogram (ECG). Time from PCI to myocardial rupture was 11 ± 7 hours. All patients showed TMP grade 0 or 1 and an increase in sum of ST-segment elevation after PCI (1.9 ± 0.5 vs 2.5 ± 0.7 mV; P = .032), suggesting severely failed reperfusion at the level of microcirculation as the common feature to develop early myocardial rupture after PCI for STEMI.     

Association between level of platelet inhibition after early use of abciximab and myocardial reperfusion in ST-elevation acute myocardial Infarction treated by primary percutaneous coronary intervention

The interindividual response to antiplatelet treatment is considerable, with the magnitude of response often related to the appearance of clinical events after elective percutaneous coronary intervention (PCI). We investigated whether platelet aggregation inhibition (PAI) by early administration of abciximab would affect myocardial reperfusion outcomes observed after PCI in patients with acute ST-elevation myocardial infarction (STEMI). Consecutive patients with STEMI who were treated with PCI in our center were recruited (n = 56). Successful reperfusion was defined as a final Thrombolysis In Myocardial Infarction grade 3 flow, myocardial blush grade 2 or 3, and ST-segment resolution >50%. PAI grade was determined with the Ultegra Rapid Platelet Function Assay. Successful reperfusion criteria were observed in 34 patients (61%). There were 6 patients (11%) with a PAI value <80% and 34 (61%) with a PAI value > or =95%. Eight patients (36%) of those whose PAI was <95% had all the indicators of successful reperfusion compared with 26 patients (77%) whose PAI was > or =95% (p = 0.005). After adjusting for other variables (time from symptom onset to balloon, which was independently associated with myocardial reperfusion), the relation remained significant (p = 0.006). In conclusion, in patients with STEMI that was treated with direct PCI, higher platelet inhibition responses with early administration of abciximab were associated with better myocardial reperfusion outcomes.     

Feasibility and applicability of computer‐assisted myocardial blush quantification after primary percutaneous coronary intervention for ST‐segment elevation myocardial infarction

Objectives : The aim of the study was to evaluate whether the “Quantitative Blush Evaluator” (QuBE) score is associated with measures of myocardial reperfusion in patients with ST‐segment elevation myocardial infarction (STEMI) treated in two hospitals with 24/7 coronary intervention facilities. Background : QuBE is an open source computer program to quantify myocardial perfusion. Although QuBE has shown to be practical and feasible in the patients enrolled in the Thrombus Aspiration during Percutaneous Coronary Intervention in Acute Myocardial Infarction Study (TAPAS), QuBE has not yet been verified on reperfusion outcomes of primary percutaneous coronary intervention (PCI) patients treated in other catheterization laboratories. Methods : Core lab adjudicated angiographic outcomes and QuBE values were assessed on angiograms of patients who were enrolled in the PRoximal Embolic Protection in Acute myocardial infarction and Resolution of ST‐Elevation (PREPARE) trial. ST‐segment resolution immediately after PCI measured by continuous ST Holter monitoring was calculated by a blinded core lab. Results : The QuBE score could be assessed on 229 of the 284 angiograms (81%) and was significantly associated with visually assessed myocardial blush grade (P < 0.0001). Patients with improved postprocedural Thrombolysis in Myocardial Infarction‐graded flow, myocardial blush grade, ST‐segment resolution immediately after PCI, or a small infarct size measured by peak CK‐MB had a significant better QuBE score. Conclusions : QuBE is feasible and applicable at angiograms of patients with STEMI recorded at other catheterization laboratories and is associated with measures of myocardial reperfusion. © 2010 Wiley‐Liss, Inc.     

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.     

Comparison of myocardial perfusion after successful primary percutaneous coronary intervention in patients with ST-elevation myocardial infarction with versus without diabetes mellitus

Patients with diabetes mellitus (DM) have an adverse prognosis after ST-segment elevation myocardial infarction (STEMI). Whether DM was associated with impaired myocardial reperfusion after successful primary percutaneous coronary intervention for STEMI was investigated. Myocardial reperfusion was assessed by ST-segment resolution and myocardial blush grade (MBG). A total of 386 patients were studied, of whom 64 (17%) had DM. These patients more frequently had reduced MBG (20% vs 10%, p = 0.02) and incomplete ST-segment resolution (55% vs 35%, p = 0.02) compared with patients without DM. After multivariate analysis, DM was still associated with impaired ST resolution (odds ratio 2.1, p = 0.03) and reduced MBG (odds ratio 2.2, p = 0.03).     

Protection of Distal Embolization in High-Risk Patients with Acute ST-Segment Elevation Myocardial Infarction (PREMIAR)

Distal embolization may decrease myocardial reperfusion after primary percutaneous coronary intervention (PCI). Nonetheless, results of previous trials assessing the role of distal protection during primary PCI have been controversial. The Protection of Distal Embolization in High-Risk Patients with Acute ST-Segment Elevation Myocardial Infarction Trial (PREMIAR) was a prospective, randomized, controlled study designed to evaluate the role of filter-based distal protection during PCI in patients with acute ST-segment elevation myocardial infarction at high risk of embolic events (including only baseline Thrombolysis In Myocardial Infarction grade 0 to 2 flow). The primary end point was continuous monitoring of ST-segment resolution. Secondary end points included core laboratory analysis of angiographic myocardial blush, ejection fraction measured by cardiac ultrasound, and adverse cardiac events at 6 months. From a total of 194 enrolled patients, 140 subjects were randomized to PCI with or without embolic protection, and 54 were included in a registry arm due to the presence of angiographic exclusion criteria. Baseline characteristics were comparable between arms. The rate of complete ST-segment resolution (>or=70%) at 60 minutes was similar in patients treated with or without distal protection (61.2% vs 60.3%, respectively, p = 0.85). Angiographic myocardial blush (67% vs 70.7%, p = 0.73), in-hospital ejection fraction (47.4 +/- 9.9% vs 45.3 +/- 7.3%, p = 0.29), and combined end point of death, heart failure, or reinfarction at 6 months (14.3% vs 15.7%, p = 0.81) were consistently achieved in a similar proportion in the 2 groups. In conclusion, the use of filter-based distal protection is safe and effectively retrieves debris; however, such use does not translate into an improvement of myocardial reperfusion, left ventricular performance, or clinical outcomes.     

替罗非班联合冠脉内血栓导管抽吸对急诊ST段抬高心肌梗死患者PCI术血运重建的影响

目的探讨替罗非班联合冠脉内血栓导管抽吸对急诊ST段抬高心肌梗死(STEMI)患者标准经皮冠状动脉介入治疗(PCI)术血运重建的影响。方法 98例STEMI患者随机分为PCI+血栓抽吸+替罗非班组(A组),PCI+替罗非班组(B组)。观察两组患者血管再通时即刻的血流血管心肌梗死溶栓(TIMI)分级、TIMI心肌灌注(TMPG)分级、术后2h心电图ST段回落大于50%的发生率、心肌磷酸激酶同工酶(CK-MB)峰值、CK-MB峰值时间,术后2h胸痛缓解率再灌注心律失常发生率。结果 A组心肌灌注明显增加,TIMI血流及TMPG血流明显改善,术后2h心电图ST段回落大于50%的发生率、CK-MB峰值、CK-MB峰值时间,术后2h内胸痛缓解率及再灌注心律失常发生率优于对照组。结论血栓抽吸与替罗非班联合治疗可改善急性ST段抬高性心肌梗死患者冠脉内血栓病变的血栓负荷、冠状动脉血流、心肌灌注,改善患者预后。     

Circulating cytochrome c as potential biomarker of impaired reperfusion in ST-segment elevation acute myocardial infarction

In patients with ST-segment elevation acute myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (pPCI), abrupt reperfusion can induce myocardial injury and apoptotic cell death. Reperfusion-induced myocardial damage, however, cannot be easily evaluated in clinical practice because of the lack of specific biomarkers. Cytochrome c, a mitochondrial protein, is released on reperfusion into the cytosol, where it triggers the apoptotic process. It can reach the external fluid and circulating blood when cell rupture occurs. We measured the cytochrome c circulating levels in patients with STEMI undergoing pPCI, and correlated them with the clinical signs of myocardial necrosis and reperfusion. The plasma creatine kinase-MB mass and serum cytochrome c (enzyme-linked immunosorbent assay method) were serially measured in 55 patients with STEMI undergoing pPCI. The angiographic and electrocardiographic signs of myocardial reperfusion were also assessed. Cytochrome c transiently increased in all patients with STEMI, with a curve that paralleled that of creatine kinase-MB. A significant relation was found between the peak values of the 2 biomarkers (R = 0.35, p = 0.01) and between the areas under the 2 curves (R = 0.33, p = 0.02). The creatine kinase-MB peak value correlated significantly with the clinical features of infarct extension. In contrast, the cytochrome c peak value correlated inversely with the myocardial blush grade. Patients with clinical signs of myocardial reperfusion injury had a significantly greater cytochrome c peak value than patients without reperfusion injury (median 1.65 ng/ml, interquartile range 1.20 to 2.20, vs 1.1 ng/ml, interquartile range 0.65 to 1.55; p = 0.04). In conclusion, serum cytochrome c is detectable in the early phase of STEMI treated with pPCI and is associated with clinical signs of impaired myocardial reperfusion.     

Angiographic and clinical outcome in ST-segment elevation myocardial infarction patients receiving an adjunctive double bolus regimen of tirofiban for primary percutaneous coronary intervention.

BACKGROUND: Because of different dosages, the efficacy of adjunctive tirofiban therapy for primary percutaneous coronary intervention (PCI) is currently unclear. The hypothesis that a double bolus regimen of tirofiban will improve angiographic and clinical outcomes in patients with ST-segment elevation acute myocardial infarction (STEMI) undergoing PCI was tested in the present study. METHODS AND RESULTS: Primary PCI was performed in 217 STEMI patients: 80 received standard PCI (control group) and 137 received tirofiban (tirofiban group). Tirofiban was given as a bolus (10 mg/kg) in the emergency room and again upon arrival at the cardiac catheterization laboratory, followed by infusion of 0.15 mg . kg(-1) . min (-1) until the total dose reached 12.5 mg. The primary endpoint was emergency target vessel revascularization, recurrent myocardial infarction, or cardiovascular mortality at 30 days and 1 year. Baseline clinical and angiographic variables of the 2 groups were similar, as were angiographic results after PCI and bleeding complications at 30 days. The primary 30-day and 1-year endpoints were 5.1% and 11.7% in the tirofiban group, respectively, vs 10.0% (p = 0.171) and 18.8% (p = 0.151) in the control group. CONCLUSION: Although angiographic and clinical benefits were not demonstrated, the results suggest that research into an effective and uniform dosing regimen of adjunctive tirofiban therapy for PCI is warranted.     

Comparison of 600 versus 300-mg Clopidogrel loading dose in patients with ST-segment elevation myocardial infarction undergoing primary coronary angioplasty

The aim of the present study was to compare 600- and 300-mg clopidogrel loading doses in patients with ST-segment elevation myocardial infarctions who underwent primary percutaneous coronary intervention (PCI). Two hundred fifty-five consecutive patients presenting with ST-segment elevation myocardial infarctions who underwent primary PCI were enrolled. Patients were divided into 2 groups on the basis of the loading dose of clopidogrel received before the procedure (600 vs 300 mg). Procedural angiographic end points and 1-year major adverse cardiac events were compared between the 2 groups. Major adverse cardiac events were defined as death, nonfatal myocardial infarction, and target vessel revascularization. There were no significant differences in baseline clinical and angiographic features between the 2 groups: 157 (62%) in the clopidogrel 600 mg group and 98 (38%) in the 300 mg group. Patients receiving 600-mg loading dose of clopidogrel showed a significantly lower incidence of post-PCI myocardial blush grade 0 or 1 (odds ratio 0.64, 95% confidence interval 0.43 to 0.96, p = 0.03) and significantly less common no-reflow phenomenon (odds ratio 0.38, 95% confidence interval 0.15 to 0.98, p = 0.04) compared to those in the 300-mg group. Propensity-adjusted Cox analysis showed significantly higher survival free of major adverse cardiac events in patients receiving 600-mg loading dose of clopidogrel compared to those receiving the lower dose (hazard ratio 0.57, 95% confidence interval 0.33 to 0.98, p = 0.04). In conclusion, a 600-mg loading dose of clopidogrel is associated with improvements in procedural angiographic end points and 1-year clinical outcomes in patients with ST-segment elevation myocardial infarction who undergo primary PCI compared to a 300-mg dose.     

Prognostic implication of ST-segment resolution following primary percutaneous transluminal coronary angioplasty for ST-elevation acute myocardial infarction

BACKGROUND: ST-segment changes have been shown to correlate with myocardial tissue perfusion. Complete ST-segment resolution after thrombolysis in acute myocardial infarction is associated with lower mortality and better left ventricular function. Primary percutaneous transluminal coronary angioplasty (PTCA) for acute myocardial infarction restores better epicardial coronary flow to the infarct-related artery than thrombolysis. However, ST changes may persist and flow can remain poor despite a patent vessel. AIM: To examine the prognostic implication of ST-segment resolution immediately following primary and rescue PTCA for ST-elevation acute myocardial infarction (STEMI). METHODS: Records of 201 consecutive primary and rescue PTCA performed at Westmead Hospital for STEMI from January 2000 to December 2001 were reviewed. ST-segment elevation (taken 20 ms after the end of the QRS complex) was measured immediately before and after the procedure. ST-segment resolution of greater than 70% after the procedure was considered as -'complete' ST-segment resolution, whereas ST-segment resolution of less than 70% was considered as 'incomplete' ST-segment resolution. RESULTS: Of the 201 patients, 117 (58%) had complete ST-elevation resolution and 84 (42%) did not. There was a significant difference in survival free of major adverse cardiovascular events; 60% of those with complete ST-segment resolution were event-free at 2 years compared with 35% of those patients without complete ST-segment resolution. CONCLUSION: ST-segment resolution after primary and rescue PTCA for STEMI is associated with significantly higher event-free survival. The goal of primary angio-plasty should be the restoration of normal epicardial flow with normalization of ST-segments.     

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.     

Primary coronary angioplasty in patients with ST segment elevation acute myocardial infarction and diabetes

BACKGROUND: Subjects with diabetes constitute 13-25% of patients with ST segment elevation acute myocardial infarction (STEMI). In spite of the introduction of thrombolytic therapy, patients with STEMI and diabetes continue to have worse prognosis than those without diabetes. Primary percutaneous coronary intervention (PCI) has been shown in recent years to be the most effective therapy in patients with STEMI. AIM: To compare the outcome of STEMI patients with or without diabetes who underwent primary PCI. METHODS: The study group consisted of 500 consecutive patients with STEMI. The occurrence of major adverse cardiac events (MACE) which included death, reinfarction or repeated PCI of the target vessel, was analysed peri-operatively and during a six-month follow-up period.Results. Diabetes was diagnosed in 68 (13.6%) patients. The mean time duration from the onset of STEMI symptoms to treatment was similar in patients with or without diabetes (230+/-97 min vs 231+/-139 min, NS). Patients with diabetes were older (61.9+/-8.9 vs 57.9+/-10.8 years, p=0.004), had higher body mass index (29+/-4 vs 27+/-5, p=0.002), more frequent history of coronary artery disease (57.4% vs 37.9%, p=0.002), higher prevalence of arterial hypertension (71.6% vs 56.8%, p=0.02) and more frequently the left anterior descending artery as the infarct-related artery (58.8% vs 42.1%, p=0.01). Immediately after PCI, epicardial and myocardial reperfusion rates were lower in patients with rather than without diabetes (TIMI 3: 84.9% vs 91.3%, p=NS, cTFC: 32+/-26 vs 22+/-16, p<0.0001, and MPG3: 25% vs 41.9% p=0.008). Diabetes increased the risk of MACE during in-hospital period by 2.7 times. The rate of MACE during a six-month follow-up period was almost two times higher in patients with rather than without diabetes (death: 8.8% vs 5.1%, reinfarction: 1.5% vs 1.2%, repeated PCI: 11.8% vs 6.9%). CONCLUSIONS: Primary PCI-achieved epicardial and myocardial reperfusion rate is lower in STEMI patients with rather than without diabetes. The presence of diabetes almost doubles the risk of MACE during a six-month follow-up.