Normal flow (TIMI-3) before mechanical reperfusion therapy is an independent determinant of survival in acute myocardial infarction: analysis from the primary angioplasty in myocardial infarction trials

Preprocedural TIMI flow and infarct size in STEMI undergoing primary angioplasty

Despite optimal epicardial recanalization, primary angioplasty for STEMI is still associated with suboptimal reperfusion in a relatively large proportion of patients. The aim the current study was to evaluate the impact of preprocedural TIMI flow on myocardial scintigraphic infarct size among STEMI undergoing primary angioplasty. Our population is represented by 793 STEMI patients undergoing primary PCI. Infarct size was evaluated at 30 days by technetium-99m-sestamibi. Poor preprocedural TIMI flow (TIMI 0-1) was observed in 645 patients (81.3%). Poor preprocedural TIMI flow was associated with more hypercholesterolemia (p = 0.012), and a trend in lower prevalence of diabetes (p = 0.081). Preprocedural TIMI flow significantly affected scintigraphic and enzymatic infarct size. Similar findings were observed in the analysis restricted to patients with postprocedural TIMI 3 flow. The impact of preprocedural TIMI flow on scintigraphic infarct size was confirmed when the analysis was performed according to the percentage of patients above the median (p < 0.001) and after adjustment for baseline confounding factors (Hypercholesterolemia and diabetes) [adjusted OR (95% CI) for pre preprocedural TIMI 3 flow = 0.59 (0.46-0.75), p < 0.001]. This study shows that among patients with STEMI undergoing primary angioplasty, poor preprocedural TIMI flow is independently associated with larger infarct size.

Angiographic characteristics of definite stent thrombosis: role of thrombus grade, collaterals, epicardial coronary flow, and myocardial perfusion

OBJECTIVES

To characterize the prevalence of thrombus burden, collateral vessels to the infarct-related artery, epicardial coronary artery flow, and myocardial perfusion in patients with angiographically confirmed definite stent thrombosis (ST), and to define their relationship with associated treatments and outcomes.

BACKGROUND

Angiographic characteristics of ST are not well defined.

METHODS

All cases of angiographically determined ST at five academic hospitals from 2005 to 2012 were reviewed. Demographic, procedural, and angiographic characteristics were recorded. In-hospital and 1-year follow-up data were obtained.

RESULTS

Among 205 cases of angiographic definite ST (60 ± 8 years; 87% male), the majority presented with late/very late ST (69%) and STEMI (66%). High-risk angiographic findings at presentation included thrombus grade 4-5 (87%), absence of collateral vessels (76%), and reduced initial TIMI 3 flow (90%). Final TIMI 3 flow was achieved in 90% of patients and was associated with greater use of aspiration thrombectomy (60% vs. 25%; P = 0.003), glycoprotein IIb/IIIa inhibitors (80% vs. 30%, P < 0.001), and repeat stenting (67% vs. 10%, P < 0.001). A final myocardial perfusion grade of 2-3 was achieved in 79% of patients and was associated with greater use of aspiration thrombectomy (61% vs. 36%, P = 0.003). After multivariable logistic regression, aspiration thrombectomy (AOR 2.6, 95% CI 1.3-5.2) and implantation of a new stent (AOR 2.1, 95% CI 1.1-4.3) were associated with optimal combined epicardial flow and myocardial perfusion. At 1-year follow-up, significantly lower risk of repeat ST (HR 0.1; 95% CI 0.1,0.2; P < 0.001) among patients with initial TIMI 3 flow at index ST was observed.

CONCLUSIONS

The majority of ST patients present with late/very late ST with high thrombus burden and STEMI. Presence of collateral vessels and low thrombus burden is cardioprotective, while reduced initial TIMI flow is associated with larger infarct size and recurrent ST. Aspiration thrombectomy and repeat stenting are associated with improved epicardial coronary artery flow and myocardial perfusion among patients treated for ST. © 2014 Wiley Periodicals, Inc.

Kinetics of high-sensitivity cardiac troponin T or troponin I compared to creatine kinase in patients with revascularized acute myocardial infarction

Cardiac biomarkers are the cornerstone of the biological definition of acute myocardial infarction (AMI). The key role of troponins in diagnosis of AMI is well established. Moreover, kinetics of troponin I (cTnI) and creatine kinase (CK) after AMI are correlated to the prognosis. New technical assessment like high-sensitivity cardiac troponin T (hs-cTnT) raises concerns because of its unclear kinetic following the peak. This study aims to compare kinetics of cTnI and hs-cTnT to CK in patients with large AMI successfully treated by percutaneous coronary intervention (PCI).

We prospectively studied 62 patients with anterior AMI successfully reperfused with primary angioplasty. We evaluated two consecutive groups: the first one regularly assessed by both CK and cTnI methods and the second group by CK and hs-cTnT. Modeling of kinetics was realized using mixed effects with cubic splines.

Kinetics of markers showed a peak at 7.9 h for CK, at 10.9 h (6.9–12.75) for cTnI and at 12 h for hs-cTnT. This peak was followed by a nearly log linear decrease for cTnI and CK by contrast to hs-cTnT which appeared with a biphasic shape curve marked by a second peak at 82 h. There was no significant difference between the decrease of cTnI and CK (p=0.63). CK fell by 79.5% (76.1–99.9) vs. cTnI by 86.8% (76.6–92.7). In the hs-cTnT group there was a significant difference in the decrease by 26.5% (9–42.9) when compared with CK that fell by 79.5% (64.3–90.7).

Kinetic of hs-cTnT and not cTnI differs from CK. The role of hs-cTnT in prognosis has to be investigated.

Effects of baseline coronary occlusion and diabetes mellitus in patients with ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention

Several studies have highlighted the prognostic role of preprocedural Thrombolysis In Myocardial Infarction (TIMI) flow in the infarct-related artery (IRA) in patients with ST-segment elevation myocardial infarction (STEMI). However, the impact of preprocedural IRA occlusion in patients with diabetes with STEMI has been insufficiently studied. The aim of this study was to evaluate the effects of baseline IRA occlusion and diabetic status in patients with STEMI who underwent primary percutaneous coronary intervention by using data from a pooled analysis of randomized trials comparing intracoronary with intravenous abciximab bolus administration. A total of 3,046 patients with STEMI who underwent primary percutaneous coronary intervention were included. Diabetes was present in 578 patients (19%). The primary outcome was mortality after a median follow-up period of 375 days. Secondary end points were reinfarction and stent thrombosis. In patients without diabetes, IRA occlusion versus no occlusion was not associated with increased rates of mortality (4.3% vs 2.7%, p = 0.051) and reinfarction (3.3% vs 2.5%, p = 0.33). Patients with diabetes with IRA occlusion compared with those without occlusion showed higher rates of mortality (10.6% vs 4.6%, p = 0.01) and reinfarction (5.6% vs 2.1%, p = 0.03). Baseline IRA occlusion increased the rate of stent thrombosis in the nondiabetic (2.1% vs 1.0%, p = 0.04) and diabetic (3.2% vs 0.8%, p = 0.05) cohorts. Interaction analysis demonstrated that the risk for death and reinfarction was significantly increased when diabetes and IRA occlusion occurred concomitantly. In conclusion, patients with STEMI with diabetes and baseline IRA occlusion had disproportionately higher rates of death and reinfarction. Preprocedural IRA occlusion increased the risk for stent thrombosis, irrespective of diabetic status.

Impact of Timing of Eptifibatide Administration on Preprocedural Infarct-Related Artery Patency in Acute STEMI Patients Undergoing Primary PCI

The appropriate timing of eptifibatide initiation for acute ST segment elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (PCI) remains unclear. This study aimed to analyze the impact of timing of eptifibatide administration on infarct-related artery (IRA) patency in STEMI patients undergoing primary PCI. Acute STEMI patients who underwent primary PCI (n = 324) were enrolled in this retrospective study; 164 patients received eptifibatide bolus ≤ 30 minutes after emergency department (ED) admission (group A) and 160 patients received eptifibatide bolus > 30 minutes after ED admission (group B). The primary endpoint was preprocedural IRA patency. Most patients in group A (90%) and group B (89%) were late presenters (> 2 hours after symptom onset). The two groups had similar preprocedural thrombolysis in myocardial infarction 2 or 3 flow of the IRA (26 vs. 24%, p = not significant [NS]), similar creatine kinase-MB (CK-MB) levels at 8 hours after admission (339 vs. 281 U/L, p = NS), similar left ventricular ejection fraction (LVEF) (52 vs. 50%, p = NS), and similar 30-day mortality (2 vs. 7%, p = NS). Compared with group B, patients in group A had shorter door-to-device time (p < 0.001) and shorter procedural time (p = 0.004), without increased bleeding risk (13 vs. 18%, p = NS). Earlier intravenous administration of eptifibatide before primary PCI did not improve preprocedural IRA patency, CK-MB level at 8 hours after admission, LVEF and 30-day mortality compared with patients who received intravenous eptifibatide that was administered later.

Oxidative Stress and Spontaneous Reperfusion of Infarct-Related Artery in Patients With ST-Segment Elevation Myocardial Infarction

In the pathogenesis of atherosclerosis, oxidative stress plays a major role in plaque instability, rupture, and erosion, which subsequently leads to thrombus formation and causes total infarct-related artery (IRA) occlusion. We investigated the relationship between spontaneous reperfusion (SR) of IRA and oxidative stress in patients with anterior ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention. A total of 341 consecutive patients with anterior STEMI were prospectively included in the present study. Patients were divided into 2 groups according to their thrombolysis in myocardial infarction (TIMI) flow grade: SR group (66 patients, TIMI flow 3) and non-SR group (275 patients, TIMI flow 0-2). On multivariate logistic regression analysis, oxidative stress index (β = 0.868, 95% confidence interval [CI] = 0.806-0.934, P < .001), neutrophil to lymphocyte ratio, uric acid, mean platelet volume, Killip 2 to 4 class, and initial SYNTAX score were independently associated with SR. Oxidative stress as well as inflammation may play a pivotal role in the pathogenesis of SR in patients with STEMI.

A novel predictor of infarct-related artery patency before percutaneous intervention and in-hospital outcomes for ST-segment elevation myocardial infarction patients: serum bilirubin level

Introduction

Previous studies have reported a relationship between serum bilirubin levels and coronary artery disease (CAD). However, data are rare up to now regarding the relation of bilirubin levels with infarct-related artery (IRA) patency in the setting of ST-segment elevation myocardial infarction (STEMI). Moreover, previous studies reported that increased bilirubin was related to impaired post-intervention coronary flow. To our knowledge, the association between serum total bilirubin (TB) levels and pre-primary percutaneous coronary intervention (PCI) with patency of IRA flow in STEMI patients has not been investigated.

Aim

To evaluate the association of TB with pre-primary PCI, coronary flow and in-hospital major adverse cardiac events (MACE) in patients with STEMI.

Material and methods

A total of 360 consecutive patients with STEMI (mean age = 61.4 ±13.7 years) admitted within 12 h from the time of symptom onset were enrolled. Patients were divided into 2 groups based on the serum TB levels. We defined normal flow as pre-PCI TIMI 3 flow, while impaired flow was defined as pre-PCI TIMI ≤ 2 flow.

Results

Pre-PCI impaired flow was higher in the TB group than pre-PCI normal flow (p < 0.001). In-hospital mortality and MACE were significantly higher in the high TB group (p = 0.002, p < 0.001 respectively). In the receiver operating characteristic curve analysis, TB > 0.825 mg/dl predicted impaired IRA flow before p-PCI with a sensitivity of 79% and specificity of 71%.

Conclusions

The TB is an inexpensive and readily available marker for STEMI patients undergoing PCI. It can be used for risk stratification in this patient population.

Local Intracoronary Eptifibatide versus Mechanical Aspiration in Patients with Acute ST-Elevation Myocardial Infarction

Objectives. We compared local delivery of intracoronary eptifibatide via perfusion catheter to thrombus aspiration in primary PCI. Background. Perfusion catheter increases local concentration of the drugs at the culprit site and prolongs their residency time. Methods. 75 patients with acute STEMI were randomized to three groups: 25 received local intracoronary eptifibatide and verapamil via perfusion catheter; 25 patients were managed by Diver CE thrombectomy device and 25 patients by primary PCI without thrombus aspiration. Primary end point was assessment of postprocedural TIMI flow, MPG, and corrected TIMI frame count (cTFC) in the culprit vessel. Results. Perfusion catheter was superior to thrombus aspiration and conventional PCI as regards MBG (68% versus 36% in Diver CE and 20% in the control arm; P value = 0.002), with shorter cTFC rates than thrombectomy and control groups (20.76 ± 4.44 versus 26.68 ± 8.40 and 28.16 ± 5.96, resp.; P = 0.001). TIMI flow was not different between the 3 groups. Eptifibatide led to less time to peak CK (13.12 hours versus 16.5 and 19.5 hours, respectively, P value = 0.001). Conclusion. Local intracoronary eptifibatide by perfusion catheter reduces thrombus burden with better results in microvascular perfusion assessed by cTFC and MBG compared to aspiration device or conventional PCI.

Effect of Early Treatment With Tirofiban on Initial TIMI Grade 3 Flow of Patients With ST Elevation Myocardial Infarction

Background:

Before primary percutaneous coronary intervention (PCI) in patients with ST elevation myocardial infarction (STEMI), it is not clear whether a routine early administration of glycoprotein IIb/IIIa inhibitors in the emergency ward is beneficial or their administration in selected cases in the catheterization laboratory.

Objectives:

The present randomized clinical trial sought to investigate whether an earlier administration of Tirofiban could exert any impact on TIMI grade 3 flows and ST resolution in the electrocardiography of patients with STEMI before primary PCI.

Materials and Methods:

Patients with STEMI within twelve hours of symptom commencement were included if primary PCI was planned to be performed within ninety minutes of admission and excluded if they had contraindications for Tirofiban. Seventy patients were randomized to receive 25 μg/kg of bolus Tirofiban early in the emergency ward (the early Tirofiban group) in three minutes and 70 did not receive Tirofiban (the control group). The primary endpoint of the study was a Thrombolysis in Myocardial Infarction (TIMI) grade 3 flows on the initial angiogram. The study is registered as IRCT201105126463N1 in: www.irct.ir.

Results:

The study population had a mean age of 57.17 ± 10.09 years and included 79.3 % males. TIMI grade 3 flow was seen in 15 (21.4 %) patients of the Tirofiban group and 7 (10 %) of the control group (P = 0.06, odds ratio = 0.407, and 95 % confidence interval = 0.155-1.072). Complete ST resolution was seen in 30 (42.9 %) patients of the Tirofiban group and 34 (48.6 %) of the control group (P = 0.5).

Conclusion:

Although TIMI grade 3 flows trended to be higher in the patients who received early Tirofiban in the emergency ward, the difference did not constitute statistical significance and possible benefits, therefore, require further clarification.

Effects of Upstream Administration of Tirofiban Before Percutaneous Coronary Intervention on Spontaneous Reperfusion and Clinical Outcomes in Acute ST-Segment Elevation Myocardial Infarction

We assessed the effects of upstream administration of the glycoprotein IIb/IIIa inhibitor tirofiban before percutaneous coronary intervention (PCI) on spontaneous reperfusion (SR) of infarct-related artery (IRA) and the clinical outcomes in patients with ST-segment elevation myocardial infarction (STEMI). The incidence of SR of the IRA was significantly higher in the tirofiban group than in the no-tirofiban group (141 [36.5%] vs 21 [17.2%], P < .001). By multivariate logistic regression analysis, use of tirofiban (odds ratio 2.32, 95% confidence interval 1.25-4.31, P = .008) independently predicted the occurrence of SR. Kaplan-Meier survival analysis demonstrated that major adverse cardiovascular event-free survival was significantly higher in patients treated with tirofiban than in patients without tirofiban at 30-day (log rank = 11.65, P = .001) and 90-day follow-up (log rank = 16.79, P < .001). Upstream administration of tirofiban is significantly associated with increased SR of the IRA and favorable clinical prognosis in patients undergoing PCI for STEMI.

Can Admission Neutrophil to Lymphocyte Ratio Predict Infarct-Related Artery Patency in ST-Segment Elevation Myocardial Infarction

Objectives:

In this study, we aimed to investigate the relationship between neutrophil to lymphocyte ratio (NLR) and infarct-related artery (IRA) patency in patients with ST-segment elevation myocardial infarction (STEMI).

Methods:

A total of 349 patients with STEMI were recruited to this retrospective study. Baseline characteristics were reviewed. Patency of IRA was evaluated by thrombolysis in myocardial infarction flow grade.

Results:

Of all patients, 293 patients formed the occluded IRA group and 56 patients formed the patent IRA group. The NLR was significantly higher in occluded IRA group (4.4 ± 4.1 vs 1.9 ± 1.1, P < .001). Glucose levels were also higher in occluded IRA group (171.3 ± 78.0 vs 144.7 ± 49.7, P = .022). Regression analysis demonstrated admission NLR and plasma glucose levels as independent predictors of IRA patency.

Conclusion:

In this study, we found that admission NLR and glucose levels were higher in patients with occluded IRA than in patients with STEMI. We also found that NLR and glucose levels were independent predictors of IRA patency. Because hemogram is a cheap, fast, and widely available test, it can be used in daily practice as a predictor of IRA patency.

Impact of TIMI 3 patency before primary percutaneous coronary intervention for ST-elevation myocardial infarction on clinical outcome: results from the ASSENT-4 PCI study

BACKGROUND

Early restoration of blood flow of the infarct-related artery is associated with an improved outcome in patients with ST-elevation myocardial infarction (STEMI). Previous studies have shown a low mortality in patients with TIMI 3 flow before primary percutaneous coronary intervention (PCI). Most likely these patients had spontaneous recanalization of the infarct vessel and might constitute a low-risk subgroup. The purpose of the present analysis was to investigate whether TIMI 3 flow obtained with fibrinolysis before PCI is associated with a clinical outcome comparable to that in patients with spontaneous TIMI 3 flow.

METHODS

Patients with STEMI <6 hours enrolled in the ASSENT-4 PCI study were randomized to facilitated PCI with tenecteplase or primary PCI. For this analysis, patients were divided into three groups according to the TIMI flow of the infarct vessel before PCI: TIMI 0/1, TIMI 2, and TIMI 3.

RESULTS

From a total of 1617 patients, 861 had TIMI 0/1, 279 had TIMI 2, and 477 TIMI 3 flow. The rates of TIMI 3 flow after PCI were 84.6, 89.7, and 95.6%, respectively. Complete ST resolution was observed most often in the TIMI 3 flow group (47.5, 53.6, and 58.6%). The incidence of cardiogenic shock (6.2, 5.5, and 3.6%) and 90-day mortality (6.1, 4.7, and 4.0%) were lowest in the group with TIMI 3 patency before PCI, respectively. The rate of TIMI 3 flow before PCI was higher in the facilitated PCI group than in the primary PCI group (43.9 vs. 15.2%). The 90-day mortality in patients with TIMI 3 before PCI was identical in the facilitated and the primary PCI groups (14/353, 4.0% vs. 5/124, 4.0%).

CONCLUSION

In this post-hoc analysis of ASSENT-4 PCI, TIMI grade 3 flow in the infarct-related artery before PCI, occurring either spontaneously or obtained by fibrinolysis, is associated with a higher TIMI patency after PCI, better improved ST resolution and a trend towards a favourable clinical outcome after 90 days.

Long-term prognostic benefit of field triage and direct transfer of patients with ST-segment elevation myocardial infarction treated by primary percutaneous coronary intervention

Direct transfer (DT) to the catheterization laboratory has been demonstrated to reduce delays in primary percutaneous coronary intervention (PPCI). However, data with regard to its effect on long-term mortality are sparse. The aim of this study was to investigate the effect of DT on long-term mortality in patients with ST-segment elevation myocardial infarctions treated with PPCI. A cohort study was conducted of 1,859 patients (mean age 63.1 ± 13 years, 80.2% men) who underwent PPCI from May 2005 to December 2010. From the whole series, 425 patients (23%) were admitted by DT and 1,434 (77%) by emergency departments. DT patients were younger (mean age 61 ± 12 vs 64 ± 12 years, p = 0.017), were more frequently men (86% vs 76%, p = 0.001), and had a higher proportion of abciximab use (77% vs 64%, p <0.0001). The DT group had a shorter median contact-to-balloon time (105 vs 122 minutes, p <0.0001) and a shorter time to treatment (185 vs 255 minutes, p <0.0001) compared with the emergency department group. Thirty-day and long-term mortality (median follow-up 2.4 years, interquartile range 1.6 to 3.2) were lower in the DT group (3% vs 6%, p = 0.049, and 9.4% vs 14.4%, p = 0.008, respectively). An adjusted Cox regression analysis proved that the DT group had an improved prognosis during follow-up (hazard ratio 0.71, 95% confidence interval 0.50 to 0.99). In conclusion, DT of patients with ST-segment elevation myocardial infarctions for PPCI was associated with fewer delays and improved survival. This benefit was maintained after long follow-up. This strategy should be emphasized in all networks of ST-segment elevation myocardial infarction care.

Comparison of in-hospital outcomes with low-dose fibrinolytic therapy followed by urgent percutaneous coronary intervention versus percutaneous coronary intervention alone for treatment of ST-elevation myocardial infarction

In patients with acute ST-elevation myocardial infarction (STEMI), a strategy of prehospital reduced dose fibrinolytic administration coupled with urgent percutaneous coronary intervention (PCI), termed FAST-PCI strategy, has been found to be superior to primary PCI (PPCI) alone. A coordinated STEMI system of care that includes FAST-PCI should offer better outcomes than a system in which prehospital diagnosis of STEMI is followed by PPCI alone. The aim of this study was to compare the in-hospital outcomes for patients treated with the FAST-PCI approach with outcomes for patients treated with the PPCI approach in a common system. The in-hospital data for 253 STEMI patients (March 2003-December 2009) treated with a FAST-PCI protocol were compared with 124 patients (January 2010-August 2011) treated with PPCI strategy alone. In-hospital mortality was the primary comparator. Stroke, major bleeding, and reinfarction during index hospitalization were also compared. The in-hospital mortality was significantly lower with FAST-PCI than with PPCI (2.77% vs 10.48%, p = 0.0017). Rates of stroke, reinfarction, and major bleeding were similar in the 2 groups. There was a lower frequency of pre-PCI Thrombolysis In Myocardial Infarction 0 flow (no patency) seen in patients treated with FAST-PCI compared with the PPCI patients (26.7% vs 62.7%, p <0.0001). Earlier infarct artery patency in the FAST-PCI group had a favorable impact on the incidence of cardiogenic shock on hospital arrival (3.1% vs 20.9%, p <0.0001). In conclusion, compared with a PPCI strategy in a common STEMI system of care, the FAST-PCI strategy was associated with earlier infarct artery patency and lower incidence of cardiogenic shock, as well as with reduced in-hospital mortality.

Facilitated/pharmaco-invasive approaches in STEMI

Primary percutaneous coronary intervention (PCI) is the preferred reperfusion method in patients with ST-elevation myocardial infarction (STEMI), when performed in a timely manner and by skilled operators. However, this strategy has shown to be limited in environments with lack of PCI facilities and delay in the first medical contact-to-balloon time for logistic reasons. Pretreatment with fibrinolysis and/or glycoprotein IIb/IIIa inhibitors before PCI has the potential to provide early pharmacologic reperfusion before definitive PCI in STEMI patients. However, current data suggest that facilitated PCI does not offer any advantage over primary PCI. Conversely, a role for pharmacoinvasive recanalization, defined as pharmacological reperfusion followed by rapid transfer for routine delayed coronary angiography and PCI may still be considered in centers without on-site PCI capability.

Incidence and outcomes of no-reflow phenomenon during percutaneous coronary intervention among patients with acute myocardial infarction

Previous studies describing the no-reflow phenomenon in patients with acute myocardial infarction (AMI) undergoing percutaneous coronary intervention (PCI) were largely confined to single-center studies or small registries. To better characterize the incidence, predictors, and outcomes of the no-reflow phenomenon in a large contemporary population, we analyzed patients with AMI who were undergoing PCI of native coronary artery stenoses in the CathPCI Registry from January 1, 2004 through September 5, 2008 (n = 291,380). The angiographic no-reflow phenomenon was site reported using a standardized definition. No-reflow developed in 2.3% of the patients with AMI (n = 6,553) during PCI. Older age, ST-segment elevation AMI, prolonged interval from symptom onset to admission, and cardiogenic shock were clinical variables independently associated with the development of no-reflow (p <0.001). The angiographic factors independently associated with no-reflow included longer lesion length, higher risk class C lesions, bifurcation lesions, and impaired preprocedure Thrombolysis In Myocardial Infarction flow (p <0.001). No-reflow was associated with greater in-hospital mortality (12.6% vs 3.8%, adjusted odds ratio 2.20, 95% confidence interval 1.97 to 2.47, p <0.001) and unsuccessful lesion outcome (29.7% vs 6.6%, adjusted odds ratio 4.70, 95% confidence interval 4.28 to 5.17, p <0.001) compared to patients without no-reflow. In conclusion, the development of no-reflow, although relatively uncommon during PCI for AMI, is associated with adverse clinical outcomes. Upfront strategies to reduce the incidence of no-reflow could be considered for high-risk patients to improve outcomes.

Benefit of percutaneous coronary intervention in early latecomers with acute ST-segment elevation myocardial infarction

The clinical benefit of percutaneous coronary intervention (PCI) is controversial in stable early latecomers with ST-segment elevation myocardial infarction (STEMI). We evaluated the efficacy of PCI in 2,344 stable patients with STEMI presenting 12 to 72 hours after symptom onset. Patients who had impaired hemodynamics or who had undergone fibrinolysis or immediate or urgent PCI were excluded. The patients were divided into the PCI group (n = 1,889) and medical treatment group (n = 455). The 12-month clinical outcome was compared between the 2 groups. After adjustment using propensity score stratification, the PCI group had lower mortality (3.1% vs 10.1%; hazard ratio 0.31; 95% confidence interval 0.20 to 0.47; p <0.001) and a lower incidence of composite death/myocardial infarction (3.8% vs 11.2%; hazard ratio 0.36; 95% confidence interval 0.25 to 0.53; p <0.001) at 12 months. The benefit of PCI was consistent across all subgroups, including patients presenting without chest pain. In conclusion, in stable patients with STEMI presenting 12 to 72 hours after symptom onset, PCI was associated with significant improvement in the 12-month clinical outcome.

Lessons Learned from STEMI Clinical Trials

Coronary artery disease is the leading cause of the death in the United States. From 2009 to 2010, however, the rate of heart disease causing death decreased by 2.5% in part due to evolving techniques used to treat and prevent heart disease. Management of acute ST-segment elevation myocardial infarction (STEMI) has evolved accordingly and the studies investigating treatment strategies that have led to an evidence-based approach are reviewed in this article.

Pharmacoinvasive Management

The goal of treatment of patients with ST-segment elevation myocardial infarction (STEMI) is timely restoration of myocardial blood flow. Primary percutaneous coronary intervention (PCI) remains the treatment of choice for STEMI patients, as shown in multiple clinical trials. However, because of logistic constraints, timely primary PCI may not be possible for many STEMI patients, most of whom are treated with fibrinolysis. Debate continues as to whether, and when, patients treated with fibrinolysis should undergo subsequent PCI. Current data support the strategy of early routine PCI after fibrinolysis rather than the conservative standard-care approach or rescue PCI for failed lysis.

Association of Mean Platelet Volume and Pre- and Postinterventional Flow With Infarct-Related Artery in ST-Segment Elevation Myocardial Infarction

Platelets play a role in the pathogenesis of ST-segment elevation myocardial infarction (STEMI). We assessed the relationship between mean platelet volume (MPV) on admission and pre- and postinterventional flow with the infarct-related artery (IRA) in patients with STEMI. We prospectively included 840 patients with STEMI who underwent primary percutaneous coronary intervention (PCI). The patients were divided into 3 groups according to MPV tertiles. Pre- and post-PCI Thrombolysis In Myocardial Infarction (TIMI) flow grade was determined. Initial TIMI flow grade 3 was accepted as patent IRA. After the primary PCI, normal flow was defined as post-PCI TIMI flow 3. When the MPV was increased, the incidence of pre-PCI patent IRA ( P = .004) and post-PCI normal TIMI flow ( P < .001) was significantly decreased. Multivariate analysis showed that MPV was independently associated with post-PCI TIMI flow grade.

Relationship between treatment delay and final infarct size in STEMI patients treated with abciximab and primary PCI

BACKGROUND

Studies on the impact of time to treatment on myocardial infarct size have yielded conflicting results. In this study of ST-Elevation Myocardial Infarction (STEMI) treated with primary percutaneous coronary intervention (PCI), we set out to investigate the relationship between the time from First Medical Contact (FMC) to the demonstration of an open infarct related artery (IRA) and final scar size.Between February 2006 and September 2007, 89 STEMI patients treated with primary PCI were studied with contrast enhanced magnetic resonance imaging (ceMRI) 4 to 8 weeks after the infarction. Spearman correlation was computed for health care delay time (defined as time from FMC to PCI) and myocardial injury. Multiple linear regression was used to determine covariates independently associated with infarct size.

RESULTS

An occluded artery (Thrombolysis In Myocardial Infarction, TIMI flow 0-1 at initial angiogram) was seen in 56 patients (63%). The median FMC-to-patent artery was 89 minutes. There was a weak correlation between time from FMC-to-patent IRA and infarct size, r = 0.27, p = 0.01. In multiple regression analyses, LAD as the IRA, smoking and an occluded vessel at the first angiogram, but not delay time, correlated with infarct size.

CONCLUSIONS

In patients with STEMI treated with primary PCI we found a weak correlation between health care delay time and infarct size. Other factors like anterior infarction, a patent artery pre-PCI and effects of reperfusion injury may have had greater influence on infarct size than time-to-treatment per se.

Comparison of direct stenting with conventional stent implantation in acute myocardial infarction

Small studies have suggested that direct stenting without balloon predilatation in ST-segment elevation myocardial infarction may reduce microcirculatory dysfunction. To examine the clinical benefits of direct stenting in a large cohort of patients who underwent primary percutaneous coronary intervention treated with contemporary pharmacotherapy, the 1-year outcomes from the multicenter, randomized Harmonizing Outcomes With Revascularization and Stents in Acute Myocardial Infarction (HORIZONS-AMI) trial were analyzed. A total of 3,602 patients with ST-segment elevation myocardial infarction who underwent primary percutaneous coronary intervention were enrolled. The present study cohort consisted of 2,528 patients in whom single lesions (excluding bypass grafts) were treated with stent implantation. At operator discretion, direct stenting was attempted in 698 patients (27.6%), and stenting was performed after predilatation in 1,830 patients (72.4%). Propensity-score matching was performed to reduce bias. Direct stenting was successful in 677 patients (97.0%). ST-segment resolution at 60 minutes after the procedure was improved in patients who underwent direct compared to conventional stenting (median 74.8% vs 68.9%, respectively, p = 0.01). At 1-year follow-up, direct compared to conventional stenting was associated with a significantly lower rate of all-cause death (1.6% vs 3.8%, p = 0.01) and stroke (0.3% vs 1.1%, p = 0.049), with nonsignificant differences in target lesion revascularization, myocardial infarction, stent thrombosis, and major bleeding. Death at 1 year remained significantly lower in the direct stenting group after multivariate adjustment (hazard ratio 0.42, 95% confidence interval 0.21 to 0.86, p = 0.02) and in a propensity score-based analysis (hazard ratio 0.92, 95% confidence interval 0.88 to 0.95, p = 0.02). In conclusion, compared to stent implantation after predilatation, direct stenting is safe and effective in appropriately selected lesions in patients with ST-segment elevation myocardial infarction who undergo primary percutaneous coronary intervention and may result in improved survival.

The effect of pre-hospital glycoprotein IIb-IIIa inhibitors on angiographic outcome in STEMI patients who are candidates for primary PCI

OBJECTIVES

Aim of this study was to assess the effect of early initiation of high bolus dose tirofiban on top of dual antiplatelet therapy on angiographic outcome before and after primary percutaneous coronary intervention (PCI) in ST-elevation myocardial infraction patients.

BACKGROUND

Glycoprotein IIb/IIIa inhibitors are effective inhibitors of platelet aggregation, and have shown to reduce thrombotic complications in patients undergoing PCI.

METHODS

This is a pre-specified angiographic analysis of the On-TIME 2 trial (N = 984) and its open label run-in phase (N = 414). All angiographic parameters, including quantitative coronary angiography (QCA) were performed in an independent angiographic core lab.

RESULTS

Of the 1,398 patients, 709 patients (50.7%) were randomized to pre-hospital tirofiban. An open infarct related vessel (TIMI 2 or 3 flow) at initial angiography was more often present in the tirofiban group as compared to the no tirofiban group (58.3% vs. 49.7%, P = 0.002). Tirofiban also reduced initial thrombus burden (P for trend = 0.035) as well as thrombus grade 5 (46.9% vs. 54.3%, P = 0.016) and showed a trend toward a reduction in large thrombus burden (LTB) (69.4% vs. 74.5%, P = 0.055). After PCI, a trend towards a lower corrected TIMI frame count (cTFC) in the tirofiban group was found. A significant interaction was found with time of initiation of study drug, with highest efficacy of tirofiban when given within 76 min after symptom onset, with a significantly lower cTFC after PCI (21.9 ± 17.6 vs. 23.9 ± 18.5, P = 0.008, P for interaction P = 0.006).

CONCLUSION

In patients undergoing primary PCI, pre-hospital administration of tirofiban reduces initial thrombus burden and improves initial patency of the infarct related vessel before PCI. Initiation of tirofiban seems to be most effective when given very early after the onset of symptoms; however, this finding needs confirmation in other studies.

CLINICAL TRIAL REGISTRATION

The On-TIME 2 trial is registered, at http://isrctn.org, number ISRCTN06195297.

Efficacy of clotinab in acute myocardial infarction trial-ST elevation myocardial infarction (ECLAT-STEMI)

BACKGROUND

This study investigated the efficacy and the safety of the upstream glycoprotein (Gp) IIb/IIIa inhibitor (clotinab; ISU ABXIS, Seoul, Republic of Korea) under 600-mg clopidogrel pretreatment compared with provisional use in ST-elevation myocardial infarction (STEMI).

METHODS AND RESULTS

A total of 786 STEMI patients were randomized to upstream use in the emergency room (ER) (n = 392) or provisional use during percutaneous coronary intervention (PCI) (n = 394). All patients were prescribed 600-mg clopidogrel in the ER. The primary endpoint was the 30-day incidence of composite events including death, nonfatal myocardial infarction, target vessel revascularization, and stroke. There was no significant difference in the events that occurred in 40 patients (10.2%) in the upstream arm and 55 patients (14.0%) in the provisional arm during the 30 days (odds ratio 0.70, 95% confidence interval 0.45-1.08). Major bleeding was higher in the upstream arm (1.5% vs. 0%, P = 0.02). However, there was a significant reduction in 30-day composite events in the upstream arm in the high-risk population (Killip class ≥II or GRACE score >140).

CONCLUSIONS

The upstream use of clotinab under a 600-mg clopidogrel loading may not significantly reduce cardiac events following primary PCI but may improve the clinical outcome in high-risk patients.

Early glycoprotein IIb-IIIa inhibitors in primary angioplasty-abciximab long-term results (EGYPT-ALT) cooperation: individual patient's data meta-analysis

BACKGROUND

Even although time to treatment has been shown to be a determinant of mortality in primary angioplasty, the potential benefits are still unclear from early pharmacological reperfusion by glycoprotein (Gp) IIb-IIIa inhibitors. Therefore, the aim of this meta-analysis was to combine individual data from all randomized trials conducted on upstream as compared with late peri-procedural abciximab administration in primary angioplasty.

METHODS

The literature was scanned using formal searches of electronic databases (MEDLINE and EMBASE) from January 1990 to December 2010. All randomized trials on upstream abciximab administration in primary angioplasty were examined. No language restrictions were enforced.

RESULTS

We included a total of seven randomized trials enrolling 722 patients, who were randomized to early (n = 357, 49.4%) or late (n = 365, 50.6%) peri-procedural abciximab administration. No difference in baseline characteristics was observed between the two groups. Follow-up data were collected at a median (25th-75th percentiles) of 1095 days (720-1967). Early abciximab was associated with a significant reduction in mortality (primary endpoint) [20% vs. 24.6%; hazard ratio (HR) 95% confidence interval (CI) = 0.65 (0.42-0.98) P = 0.02, P(het) = 0.6]. Furthermore, early abciximab administration was associated with a significant improvement in pre-procedural thrombolysis in myocardial infarction (TIMI) 3 flow (21.6% vs. 10.1%, P < 0.0001), post-procedural TIMI 3 flow (90% vs. 84.8%, P = 0.04), an improvement in myocardial perfusion as evaluated by post-procedural myocardial blush grade (MBG) 3 (52.0% vs. 43.2%, P = 0.03) and ST-segment resolution (58.4% vs. 43.5%, P < 0.0001) and significantly less distal embolization (10.1% vs. 16.2%, P = 0.02). No difference was observed in terms of major bleeding complications between early and late abciximab administration (3.3% vs. 2.3%, P = 0.4).

CONCLUSIONS

This meta-analysis shows that early upstream administration of abciximab in patients undergoing primary angioplasty for ST-segment elevation myocardial infarction (STEMI) is associated with significant benefits in terms of pre-procedural epicardial re-canalization and ST-segment resolution, which translates in to significant mortality benefits at long-term follow-up.

Predictors and implications of coronary infarct artery patency at initial angiography in patients with acute myocardial infarction (from the CADILLAC and HORIZONS-AMI Trials)

Pre-percutaneous coronary intervention (PCI) Thrombolysis In Myocardial Infarction (TIMI) grade 3 flow has been identified as a predictor of final TIMI grade 3 flow and better survival. Yet pharmacologic strategies increasing the rates of pre-PCI TIMI grade 3 flow resulted in more bleeding, without a benefit in survival. The aim of this study was to identify the predictors and implications of spontaneous reperfusion before primary PCI in patients with ST-segment elevation myocardial infarction. The Controlled Abciximab and Device Investigation to Lower Late Angioplasty Complications (CADILLAC) and Harmonizing Outcomes With Revascularization and Stents in Acute Myocardial Infarction (HORIZONS-AMI) trials were combined, and the predictors of core laboratory-determined baseline TIMI grade 3 flow and 1-year outcomes were analyzed according to baseline TIMI flow. Baseline TIMI grade 3 flow was present in 932 of 5,332 patients (17.5%). The independent predictors of baseline TIMI grade 3 flow were diabetes, longer delay to PCI, smoking, and more extensive coronary disease. Patients with compared to those without baseline TIMI grade 3 flow had significantly higher rates of post-PCI TIMI grade 3 flow (99.1% vs 91.4%, p <0.0001) and lower 1-year all-cause mortality (2.7% vs 4.3%, p = 0.02). By multivariate analysis, baseline TIMI grade 3 flow (hazard ratio 1.65, 95% confidence interval 1.01 to 2.71, p = 0.046) and final TIMI grade 3 flow (hazard ratio 3.67, 95% confidence interval 2.45 to 5.48, p <0.001) were significant independent predictors of 1-year survival. In conclusion, TIMI grade 3 flow is present in about 1 in every 6 patients before PCI and paradoxically is more common in patients with higher risk characteristics. TIMI grade 3 flow before as well as after PCI is an independent predictor of greater 1-year survival. These data should inform future trials of ST-segment elevation myocardial infarction with respect to improvement in outcomes.

Predictors of ventricular tachyarrhythmia in high-risk myocardial infarction patients treated with primary coronary intervention

Background. We investigated the association between clinical characteristics, angiographic data and ventricular arrhythmia in patients with ST-elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (PCI)Methods. In patients with STEMI (n=225), a Holter analysis was performed the first 12 hours after primary PCI.Results. A total of 151 (66%) patients had >/=1 episode of ventricular tachycardia (VT). Age <70 years (RR 4.9, 95% CI 1.8 to 12.7), TIMI 0-1 pre-PCI (RR 2.6, 95% CI 1.1 to 6.1) and peak CK (RR 3.5, 95% CI 1.9 to 5.8) were independent predictors of VT. One-year mortality was 7%, no association between mortality and presence of early VT was found.Conclusion. Ventricular tachycardia is common in the first 12 hours after primary PCI for STEMI. Independent predictors of VT are younger age, TIMI 0-1 flow prior to PCI and larger infarct size. The presence of early VT was not significantly associated with one-year mortality. (Neth Heart J 2010;18:122-8.).