Association of duration of symptoms at presentation with angiographic and clinical outcomes after fibrinolytic therapy in patients with ST-segment elevation myocardial infarction.

OBJECTIVES: We sought to determine if an underlying mechanism of the association between prolonged symptom-to-treatment times and adverse outcomes may be an association of symptom-to-treatment times with impaired Thrombolysis In Myocardial Infarction myocardial perfusion grades (TMPGs). BACKGROUND: Prolonged symptom duration among ST-segment elevation myocardial infarction (STEMI) patients undergoing fibrinolytic therapy is associated with adverse outcomes. METHODS: Angiography was performed 60 min after fibrinolytic administration in 3,845 Thrombolysis In Myocardial Infarction (TIMI) trial patients. RESULTS: The median time from symptom onset to treatment was longer among patients with impaired myocardial perfusion (3.0 h for TMPG 0/1 vs. 2.7 h for TMPG 2/3; p = 0.001). In a multivariate model, impaired tissue perfusion (TMPG 0/1) remained associated with increased time to treatment (odds ratio 1.14 per hour of delay; p = 0.007) even after adjusting for Thrombolysis In Myocardial Infarction flow grade (TFG) 3, left anterior descending infarct location, and baseline clinical characteristics. Impaired myocardial perfusion after rescue/adjunctive percutaneous coronary intervention (PCI) was associated with longer median times to treatment (3.0 h for TMPG 2/3 vs. 2.7 h for TMPG 0/1; p = 0.017), as was abnormal epicardial flow after rescue/adjunctive PCI (3.3 h for TFG 0/1/2 vs. 2.8 h for TFG 3; p = 0.005). Thirty-day mortality was associated with longer time from onset of symptoms to treatment (6.6% mortality for time to treatment >4 h vs. 3.3%; p < 0.001), even among patients undergoing rescue PCI. CONCLUSIONS: A prolonged symptom to treatment time among STEMI patients is associated with impaired myocardial perfusion independent of epicardial flow both immediately after fibrinolytic administration and after rescue/adjunctive PCI. These data provide a pathophysiologic link between prolonged symptoms due to vessel occlusion, impaired myocardial perfusion, and poor clinical outcomes.     

Association of TIMI Myocardial Perfusion Grade and ST-segment resolution with cardiovascular magnetic resonance measures of microvascular obstruction and infarct size following ST-segment elevation myocardial infarction

Background Impairment of coronary microvascular perfusion is common among patients with ST-segment elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (PCI). Cardiovascular magnetic resonance imaging (CMR) can identify microvascular obstruction (MO) following reperfusion of STEMI. We hypothesized that myocardial perfusion, as assessed by the Thrombolysis in Myocardial Infarction (TIMI) Myocardial Perfusion Grade (TMPG), would be associated with a CMR metric of MO in this population. Methods Twenty-one STEMI patients who underwent successful primary PCI were evaluated. Contrast-enhanced CMR was performed within 7 days of presentation and repeated at three months. TIMI Flow Grade (TFG), corrected TIMI Frame Count (cTFC), TMPG, MO, infarct size, and left ventricular ejection fraction (EF) were assessed. Results The median peak creatine phosphokinase (CPK) was 1,775 IU/l (interquartile range 838–3,321). TFG 3 was present following PCI in 19 (90%) patients. CMR evidence of MO was present in 52% following PCI. Abnormal post-PCI TMPG (0/1/2) was present in 48% of subjects and was associated with MO on CMR (90% MO with TMPG 0/1/2 vs. 18% MO with TMPG 3, P < 0.01). Abnormal post-PCI TMPG was also associated with a greater peak CK (median 3,623 IU/l vs. 838 IU/l, P < 0.001) and greater relative infarct size (17.3% vs. 5.2%, P < 0.01). Conclusion Among STEMI patients undergoing primary PCI, post-PCI TMPG correlates with CMR measures of MO and infarct size. The combined use of both metrics in a comprehensive assessment of microvascular integrity and infarct size following STEMI may aid in the evaluation of future therapeutic strategies.     

Percutaneous coronary intervention in patients receiving enoxaparin or unfractionated heparin after fibrinolytic therapy for ST-segment elevation myocardial infarction in the ExTRACT-TIMI 25 trial.

OBJECTIVES: We sought to evaluate whether enoxaparin (ENOX) is superior to unfractionated heparin (UFH) as adjunctive therapy for patients with ST-segment elevation myocardial infarction (STEMI) who receive fibrinolytic therapy and subsequently undergo percutaneous coronary intervention (PCI) by analyzing data from the ExTRACT-TIMI 25 (Enoxaparin and Thrombolysis Reperfusion for Acute Myocardial Infarction Treatment-Thrombolysis In Myocardial Infarction 25) trial. BACKGROUND: Limited data are available on the use of ENOX compared with UFH as adjunctive therapy in STEMI patients treated with fibrinolytic therapy and subsequent PCI. METHODS: A total of 20,479 STEMI patients who received fibrinolytic therapy were randomized to a strategy of ENOX throughout index hospitalization or UFH for at least 48 h, with blinded study drug to continue if PCI was performed. The primary end point of death or recurrent MI through 30 days was compared for ENOX versus UFH among the patients who underwent subsequent PCI (n = 4,676). RESULTS: After initial fibrinolysis, fewer patients underwent PCI through 30 days in the ENOX versus the UFH group (22.8% vs. 24.2%; p = 0.027). Among patients who underwent PCI by 30 days, the primary end point occurred in 10.7% of ENOX and 13.8% of UFH patients (0.77 relative risk; p < 0.001). There were no differences in major bleeding for ENOX versus UFH (1.4% vs. 1.6%; p = NS). Results were similar when PCI was carried out in patients receiving blinded study drug during PCI (n = 2,178). CONCLUSION: Among patients treated with fibrinolytic therapy for STEMI who underwent subsequent PCI, ENOX administration was associated with a reduced risk of death or recurrent MI without difference in the risk of major bleeding. The strategy of ENOX support for fibrinolytic therapy followed by PCI is superior to UFH and provides a seamless transition from the medical management to the interventional management phase of STEMI without the need for introducing a second anticoagulant in the cardiac catheterization laboratory.     

Angiographic and clinical outcomes in elderly subjects treated with percutaneous coronary intervention following fibrinolytic administration for ST-elevation myocardial infarction

Background Prior studies have demonstrated that the achievement of faster coronary artery flow following reperfusion therapies is associated with improved outcomes among ST-elevation myocardial infarction (STEMI) patients. The association of patient age with angiographic characteristics of flow and perfusion after rescue/adjunctive percutaneous coronary intervention (PCI) following the administration of fibrinolytic therapy has not been previously investigated. Objectives and Methods We examined the association between age (≥70 years or < 70years) and clinical and angiographic outcomes in 1472 STEMI patients who underwent rescue/adjunctive PCI following fibrinolytic therapy in 7 TIMI trials. We hypothesized that elderly patients would have slower post-PCI epicardial flow and worsened outcomes compared to younger patients. Results The 218 patients aged≥70 years (14.8%) had more comorbidities than younger patients. Although these patients had significant angiographic improvement in TTMI frame counts and rates of TIMI Grade 3 flow following rescue/adjunctive PCI, elderly patients had higher (slower) post-PCI TTMI frame counts compared to the younger cohort (25 vs 22 frames, P = 0.039) , and less often achieved post-PCI TTMI Grade 3 flow (80.1 vs 86.4% , P = 0.017). The association between age (≥70 years) and slower post-PCI flow was independent of gender, time to treatment, left anterior descending (LAD) lesion location, and pulse and blood pressure on admission. Elderly patients also had 4-fold higher mortality at 30 days (12.0 vs 2.7% , P = 0. 001). Conclusions This study suggests one possible mechanism underlying worsened outcomes among elderly STEMI patients insofar as advanced chronological age was associated with higher TTMI frame counts and less frequent TIMI Grade 3 flow after rescue/adjunctive PCI. (J Geriatr Gardiol 2005;2(1) :10-14)     

Angiographic perfusion score: an angiographic variable that integrates both epicardial and tissue level perfusion before and after facilitated percutaneous coronary intervention in acute myocardial infarction

Background

Both epicardial and myocardial perfusion have been associated with clinical outcomes in the setting of ST elevation myocardial infarction (STEMI), and the performance of adjunctive/rescue percutaneous coronary intervention (PCI) may further improve clinical outcomes after fibrinolytic administration.

Methods

The goal was to develop a simple, broadly applicable angiographic metric that takes into account indices of epicardial and myocardial perfusion both before and after PCI to arrive at a single perfusion grade in patients undergoing cardiac catheterization after fibrinolysis. The angiographic perfusion score (APS) is the sum of the Thrombolysis in Myocardial Infarction (TIMI) flow grade (TFG; 0-3) added to the TIMI myocardial perfusion grade (TMPG; 0-3) before and after PCI (total possible grade, 0-12). Failed perfusion was defined as an APS of 0 to 3, partial perfusion was defined as an APS of 4 to 9, and full perfusion was defined as an APS of 10 to 12. The APS was evaluated in patients from the Double-blind, Placebo-contolled, Multicenter Angiographic Trial of Rhumab CD18 in Acute Myocardial Infarction (LIMIT-AMI; n = 394) and Enoxaparin as Adjunctive Antithrombin Therapy for ST-Elevation Myocardial Infarction-Thrombolysis In Myocardial Infarction (ENTIRE-TIMI) 23 trials (n = 483), and infarct size (120-216 hours after AMI SPECT Technetium-99m Sestamibi data) was assessed in the LIMIT-AMI trial.

Results

The APS was associated with the incidence of death or myocardial infarction (failed, 16.7% [n = 18]; partial, 2.5% [n = 155]; full, 2.4% [n = 82]; P = .039 for trend) and larger SPECT infarct sizes (failed, median 39% [n = 10]; partial, 12% [n = 79]; and full, 8% [n = 35]; P = .002). No patient with full APS died, whereas the mortality rate was 11.1% in patients with a failed APS (P = .03).

Conclusions

The APS combines grades of epicardial and tissue level perfusion before and after PCI or at the end of diagnostic cardiac catheterization to arrive at a single angiographic variable that is associated with infarct size and the rates of 30-day death or MI. Partial or full angiographic perfusion scores are associated with a halving of infarct size, and no patients with full angiographic perfusion died.     

Association of culprit lesion calcium with angiographic and clinical outcomes in patients with ST-elevation myocardial infarction treated with fibrinolytic therapy

Coronary artery calcium has been associated with a greater extent of angiographically significant coronary artery stenoses, but the angiographic and clinical outcomes associated with culprit lesion calcium (CLC) have not been fully evaluated, particularly in the stetting of ST-elevation myocardial infarction. We hypothesized that CLC would be associated with adverse angiographic and clinical outcomes in patients who had ST-elevation myocardial infarction. Data were evaluated in 3,292 patients from 6 trials of fibrinolytic therapy for ST-elevation myocardial infarction; 243 culprit lesions (7.4%) were calcified. CLC was associated with advanced age, history of hypertension, previous coronary artery disease, greater extent of disease, angiographically evident residual thrombus, smaller minimum luminal diameter, and larger percent residual stenosis after fibrinolytic therapy. CLC was associated with lower rates of arterial patency after fibrinolytic therapy (63.3% vs 81.3% p <0.001), lower rates of Thrombolysis In Myocardial Infarction grade 3 flow (41.5% vs 57.2%, p <0.001), and higher (slower) Thrombolysis In Myocardial Infarction frame counts (52 vs 36 frames, p <0.0001, multivariate p = 0.02). CLC was also associated with increased 30-day mortality rates (6.2% vs 3.4%, p = 0.028) and 30-day rates of death, myocardial infarction, or congestive heart failure (16.5% vs 8.9%, p <0.001) and independently associated with 30-day rates of death, myocardial infarction, or congestive heart failure (odds ratio 1.6, p = 0.016) after multivariate adjustment for baseline clinical and lesion characteristics, epicardial flow, and performance of rescue/adjunctive percutaneous coronary intervention. In a model restricted to patients who had successful restoration of epicardial patency after fibrinolytic therapy, CLC was independently associated with 30-day mortality (odds ratio 2.2, p = 0.045). CLC is independently associated with indexes of poorer epicardial flow and a higher incidence of adverse clinical outcomes after fibrinolytic administration in patients who have ST-elevation myocardial infarction.     

Combined assessment of thrombolysis in myocardial infarction flow grade, myocardial perfusion grade, and ST-segment resolution to evaluate epicardial and myocardial reperfusion

The restoration of epicardial and myocardial flow remains the primary goal of reperfusion therapy in patients with ST-segment elevation myocardial infarction, but the optimal method to assess this goal has not been defined. Thrombolysis In Myocardial Infarction flow grade (TFG), myocardial perfusion grade (MPG), and ST-segment resolution (STRes) were combined to formulate a new measure of successful reperfusion in 649 patients who received pharmacologic reperfusion therapy in 3 recent phase II clinical trials of ST-segment elevation myocardial infarction. Coronary angiograms and electrocardiograms were analyzed at 60 minutes (before any intervention) after the initiation of reperfusion therapy. The complete restoration of perfusion, or the "trifecta," defined as the presence of TFG 3, MPG 3, and complete (> or =70%) STRes, occurred in 117 patients (18%). The achievement of this trifecta was associated with low rates of 30-day mortality (0% vs 3.9%, p = 0.02), congestive heart failure (CHF) (0.9% vs 7.1%, p = 0.01), and the combination of death or CHF (0.9% vs 10.7%, p = 0.001). When the results were stratified with respect to subsequent percutaneous coronary intervention (PCI) from 60 to 120 minutes, attainment of the trifecta at 60 minutes remained a strong predictor of better clinical outcomes, particularly in those patients who underwent early PCI. The achievement of TFG 3, MPG 3, and complete STRes at 60 minutes after fibrinolytic therapy and before PCI occurred in only 18% of patients but was associated with very low rates of death and CHF at 30 days. This new end point is proposed to evaluate the success of reperfusion therapy in patients who undergo early angiography.     

Relation of hyperemic epicardial flow to outcomes among patients with ST-segment elevation myocardial infarction receiving fibrinolytic therapy

In patients with ST-segment elevation myocardial infarction (STEMI), the restoration of normal epicardial flow following fibrinolytic administration is associated with improved clinical outcomes. The goal of this analysis was to examine the relation between hyperemic flow and outcomes following fibrinolytic administration for STEMI. In Clopidogrel as Adjunctive Reperfusion Therapy-Thrombolysis In Myocardial Infarction 28 (CLARITY-TIMI 28), patients with STEMI (n=3,491) treated with fibrinolytic therapy were scheduled to undergo angiography 48 to 192 hours after randomization. Corrected TIMI frame count (CTFC) and TIMI myocardial perfusion grade (TMPG) were assessed, and their associations with outcomes at 30 days were evaluated. When evaluating initial angiography of the infarct-related artery, there was a nearly linear relation between CTFC and 30-day mortality, with faster flow (lower CTFC) associated with improved outcomes. Conversely, in patients who underwent percutaneous coronary intervention (PCI), very fast flow (CTFC<14) after intervention was associated with worse outcomes. Post-PCI hyperemic flow (CTFC<14) was associated with a higher incidence of mortality (p=0.056), recurrent myocardial infarction (p=0.011), and a composite of death or myocardial infarction (p<0.001) compared with normal flow (CTFC 14 to 28). When post-PCI CTFC was further stratified by TMPG, there was a U-shaped relation between mortality and CTFC in patients with poor myocardial perfusion (TMPG 0 or 1). This relation appeared to be linear in patients with TMPG 2 or 3. In conclusion, in patients who undergo PCI after fibrinolytic therapy for STEMI, hyperemic flow on coronary angiography is associated with an increased incidence of adverse outcomes. Hyperemic flow with associated impaired myocardial perfusion may be a marker of more extensive downstream microembolization.     

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.     

Sequential risk stratification using TIMI risk score and TIMI flow grade among patients treated with fibrinolytic therapy for ST-segment elevation acute myocardial infarction

In the setting of ST-segment elevation myocardial infarction (STEMI), the Thrombolysis In Myocardial Infarction (TIMI) risk score (TRS) and indexes of epicardial and myocardial perfusion are associated with mortality. The association between TRS at presentation and angiographic indexes of epicardial and myocardial perfusion after reperfusion therapy has not been investigated. We hypothesized that TRS, TIMI flow grade (TFG), and TIMI myocardial perfusion grade (TMPG) would provide independent prognostic information and that angiographic indexes of poor flow and perfusion would be associated with a higher TRS. TRS and angiographic data were evaluated in 3,801 patients from the TIMI 4, 10A, 10B, 14, 20, 23, and 24 trials. Within each TRS stratum (TRS 0 to 2, 3 to 4, >/=5), 30-day mortality increased stepwise among patients with impaired TFG at 60 minutes after fibrinolytic administration. In a multivariate model adjusting for the TRS strata, impaired TMPG (0/1) was independently associated with higher mortality (odds ratio 2.28, p = 0.018). In a multivariate model adjusting for the TFG and infarct location, the likelihood of impaired TMPG (0/1) was greater among intermediate-risk (TRS 3 to 4) and high-risk (TRS >/=5) patients than among low-risk (TRS 0 to 2) patients (odds ratio 1.43, p = 0.019 and 1.50, p = 0.055, respectively). Thus, impaired epicardial flow and myocardial perfusion are independently associated with increased 30-day mortality among patients identified by TRS as high risk, although there is no synergism between either TFG or TMPG and TRS. High TRS at presentation is associated with abnormal myocardial perfusion, even after adjusting for possible confounders.     

Effects of glucose-insulin-potassium infusion on myocardial perfusion and left ventricular remodeling in patients treated with primary angioplasty for ST-elevation acute myocardial infarction

The role of glucose-insulin-potassium (GIK) infusion in the management of acute coronary syndrome is controversial. Limited data are available on the effects of adjunctive high-dose GIK (30% glucose, 50 IU of insulin, 80 mEq of potassium chloride infused at 1.5 ml/kg/hour over 24 hours) on myocardial perfusion and left ventricular (LV) remodeling in patients treated with primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction. In this prospective study, 73 patients were randomized to receive GIK infusion (n = 40) or saline (placebo, n = 33) in addition to standard therapy. The primary end points were myocardial perfusion after PCI and LV remodeling at 6 months. Thrombolysis In Myocardial Infarction frame count and myocardial blush grade were evaluated before and after reperfusion treatment. LV end-diastolic and end-systolic volumes, ejection fraction, and wall motion score index were assessed in each patient after PCI and after 6 months. Although no differences in final Thrombolysis In Myocardial Infarction flow were observed between the 2 groups, myocardial blush grade 3 was more frequently achieved in the GIK group (p <0.05). At 6 months, ventricular remodeling was more often observed in the control group (24% vs 3%, p <0.05). In conclusion, GIK infusion in adjunct to primary PCI in patients with ST-segment elevation myocardial infarction was safe, improved myocardial perfusion after revascularization, and was associated with less LV remodeling at follow-up.     

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.     

Diabetes mellitus, myocardial reperfusion, and outcome in patients with acute ST-elevation myocardial infarction treated with primary angioplasty (from HORIZONS AMI)

Diabetes mellitus (DM) increases mortality in acute ST-segment elevation myocardial infarction (STEMI) but the responsible mechanism is not fully elucidated. We compared the rate of successful myocardial reperfusion measured by tissue myocardial perfusion grade (TMPG) and outcomes in patients with and without DM undergoing primary percutaneous coronary intervention (PCI) for STEMI. Patients enrolled in the Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction (HORIZONS AMI) trial were analyzed according to presence of DM with respect to TMPG after PCI and outcomes at 30 days and 3 years. Multivariable logistic regression was performed to identify the independent contribution to mortality of DM and TMPG and the interaction between the 2 was assessed. Complete data were available for 3,265 patients, of whom 533 (16.3%) had DM. Diabetic patients were significantly older and heavier and had more risk factors for coronary disease and more previous MI, revascularization, and heart failure. There were no differences in rates of Thrombolysis In Myocardial Infarction grade 3 flow after PCI in the infarct artery or TMPG 2/3 between patients with and without DM. Compared to nondiabetics, mortality was significantly higher at 30 days and at 3 years in the DM group (1.8% vs 4.5%, p = 0.0002 and 5.4% vs 11.0%, p <0.0001, respectively). DM and TMPG were significantly associated with 3-year mortality, but there was no statistical interaction between DM and TMPG (p = 0.70). In conclusion, DM is associated with a significantly higher risk of death but this association is not mediated by impaired epicardial or myocardial reperfusion.     

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.     

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.     

冠状动脉内应用维拉帕米对急性心肌梗死急诊介入治疗后冠状动脉灌注、心肌灌注和临床预后的影响

目的探讨急性ST段抬高性心肌梗死（STEMI）急诊经皮冠状动脉介入治疗（PCI）时冠状动脉内应用维拉帕米对冠状动脉灌注、心肌灌注及临床预后的影响。方法本研究为前瞻性、随机、双盲、对照性临床研究。连续性入选99例STEMI拟行急诊PCI的患者,随机分为维拉帕米组与对照组。在支架释放后即刻,维拉帕米组在靶血管内注入维拉帕米200μg,对照组在靶血管内注入肝素生理盐水,比较两组PCI术前、术后和冠状动脉内注药后的冠状动脉灌注和心肌灌注的差别。冠状动脉灌注以心外膜TIMI血流（TFG）和校正的TIMI血流帧数计数（CTFC）来评价。心肌灌注以TIMI心肌灌注分级（TMPG）和心肌灌注显影（MBG）来评价。并比较两组在PCI术后1周心脏彩色超声结果、住院期间以及随访期间主要心脏不良事件（MACE）发生率上的差别。结果最终91例患者有完整资料,其中维拉帕米组47例,对照组44例,两组临床基本特征和造影特征相仿。维拉帕米组和对照组在术前和支架释放后即刻冠状动脉灌注和心肌灌注各指标差异均无统计学意义（P〉0.05）。冠状动脉内注入维拉帕米后,维拉帕米组的CTFC、TFG、MBG、TMPG均较对照组有显著改善,分别为CTFC：27.1±14.2比39.0±23.8,P=0.011;TFG≥2级：100%比90.9%,P=0.035;MBG≥2级：91.5%%比75.5%,P=0.034;TMPG≥2级：89.4%比72.7%,P=0.042。维拉帕米组和对照组PCI术后1周时左室射血分数（63.4%±8.2%比63.5%±10.3%,P=0.578）、院内MACE发生率（4.3%比9.1%,P=0.613）和3个月MACE发生率（23.9%比22.7%,P=0.894）差异均无统计学意义。结论STEMI患者急诊行PCI治疗时,冠状动脉内应用维拉帕米可显著改善冠状动脉灌注和心肌灌注水平,但未观察到其对急诊PCI术后心室重构和短期临床预后的显著影响。     

Comparative early and late outcomes after primary percutaneous coronary intervention in ST-segment elevation and non-ST-segment elevation acute myocardial infarction (from the CADILLAC trial)

We determined the outcomes of patients with acute ST-segment elevation (STE) myocardial infarction (STEMI) and non-STEMI (NSTEMI) after primary percutaneous coronary intervention (PCI). The prognosis after primary PCI in STEMI has been extensively studied and defined. Outcomes of patients who undergo primary PCI for NSTEMI are less well established. In total, 2,082 patients with ongoing chest pain for > 30 minutes consistent with acute MI were randomized to balloon angioplasty versus stenting, each with/without abciximab. Of 1,964 patients, STEMI was present in 1,725 (87.8%) and NSTEMI in 239 (12.2%). Compared with STEMI, those with NSTEMI were more likely to have delayed time-to-hospital arrival (2.4 vs 1.8 hours, p = 0.0002) and increased door-to-balloon time (3.2 vs 1.9 hours, p < 0.0001). Patients with NSTEMI were more likely to have Thrombolysis In Myocardial Infarction grade 3 flow at baseline (37.3% vs 19.4%, p < 0.0001) and higher ejection fraction (58.7% vs 55.8%, p = 0.001), but similar rates of postprocedural Thrombolysis In Myocardial Infarction grade 3 flow. At 1 year, patients with NTEMI had similar mortality (3.4% vs 4.4%, p = 0.40) but higher rates of major adverse cardiac events (24.0% vs 16.6%, p = 0.007) that was driven by more frequent ischemic target vessel revascularization (21.8% vs 11.9%, p <0.0001). In conclusion, patients with acute MI without STE who are treated with primary PCI have marked delays to treatment, similar late mortality, and increased rates of ischemic target vessel revascularization compared with patients with STEMI, despite more favorable angiographic features at presentation and similar reperfusion success. The adverse prognosis of patients with NSTEMI should be recognized and efforts made to decrease reperfusion times.     

Angiographic and clinical outcomes associated with direct versus conventional stenting among patients treated with fibrinolytic therapy for ST-elevation acute myocardial infarction

The present study reports outcomes of direct stenting versus conventional stenting, which was performed during adjunctive/rescue percutaneous coronary intervention (n = 556) in the Integrilin and Tenecteplase in Acute Myocardial Infarction trial, the Enoxaparin as Adjunctive Antithrombin Therapy for ST-Elevation Myocardial Infarction-Thrombolysis in Myocardial Infarction 23 trial, and the Fibrinolytic and Aggrastat ST-Elevation Resolution trial of fibrinolytic therapy in ST-elevation myocardial infarction. Direct stenting was associated with a lower rate of death, myocardial infarction, or congestive heart failure during hospitalization and at 30 days and was independently associated with improved in-hospital outcomes (odds ratio 0.44, 95% confidence interval 0.23 to 0.85, p = 0.014).     

Predictors of infarct size after primary coronary angioplasty in acute myocardial infarction from pooled analysis from four contemporary trials

Determinates of infarct size in patients with acute myocardial infarction (AMI) undergoing percutaneous coronary intervention (PCI) have been incompletely characterized, in part because of the limited sample size of previous studies. Databases therefore were pooled from 4 contemporary trials of primary or rescue PCI (EMERALD, COOL-MI, AMIHOT, and ICE-IT), in which the primary end point was infarct size assessed using technetium-99m sestamibi single-photon emission computed tomographic imaging, measured at the same core laboratory. Of 1,355 patients, infarct size was determined using technetium-99m sestamibi imaging in 1,199 patients (88.5%), at a mean time of 23 +/- 15 days. Median infarct size of the study population was 10% (interquartile range 0% to 23%; mean 14.9 +/- 16.1%). Using multiple linear regression analysis of 18 variables, left anterior descending infarct artery, baseline Thrombolysis In Myocardial Infarction grade 0/1 flow, male gender, and prolonged door-to-balloon time were powerful independent predictors of infarct size (all p <0.0001). Other independent correlates of infarct size were final Thrombolysis In Myocardial Infarction grade <3 flow (p = 0.0001), previous AMI (p = 0.005), symptom-onset-to-door time (p = 0.021), and rescue angioplasty (p = 0.026). In conclusion, anterior infarction, time to reperfusion, epicardial infarct artery patency before and after reperfusion, male gender, previous AMI, and failed thrombolytic therapy were important predictors of infarct size after angioplasty in patients with AMI assessed using technetium-99m sestamibi imaging and should be considered when planning future trials of investigational drugs or devices designed to enhance myocardial recovery.     

Early coronary intervention following pharmacologic therapy for acute myocardial infarction (the combined TIMI 10B-TIMI 14 experience).

Earlier studies have suggested that immediate percutaneous coronary intervention (PCI) following thrombolytic therapy for acute myocardial infarction (AMI) is associated with an increase in adverse events and that routine PCI in this setting has offered no advantage over a conservative strategy. To reassess this issue in a more recent era, we evaluated 1,938 patients from the Thrombolysis in Myocardial Infarction (TIMI) 10B and 14 trials of AMI. Patients in TIMI 10B were randomized to receive tissue plasminogen activator or TNK tissue plasminogen activator, whereas patients in TIMI 14B trial were randomized to receive thrombolytic therapy with or without abciximab. All patients underwent angiography 90 minutes after receiving pharmacologic therapy. Patients who underwent PCI were classified as having undergone a rescue procedure (TIMI 0 or 1 flow at 90 minutes), an adjunctive procedure (TIMI 2 or 3 flow at 90 minutes), or a delayed procedure (performed >150 minutes after symptom onset, median of 2.75 days). Among patients with TIMI 0 or 1 flow, there was a trend for lower 30-day mortality among patients who underwent rescue PCI than among those who did not (6% vs 17%, p = 0.01, adjusted p = 0.28). Patients who underwent adjunctive PCI had similar 30-day mortality and/or reinfarction as those who underwent delayed PCI. In a multivariate model both had lower 30-day mortality and/or reinfarction than patients with "successful thrombolysis" (i.e., TIMI 3 flow at 90 minutes) who did not undergo revascularization (p = 0.02). Thus, early PCI following AMI is associated with excellent outcomes. Randomized trials of an early invasive strategy following thrombolysis are warranted.