ST-segment Elevation Myocardial Infarction Presenting Research Articles

ST-segment resolution after primary percutaneous coronary intervention in patients with acute ST-segment elevation myocardial infarction

The association between ST-segment resolution and clinical outcome in patients with acute ST-segment elevation myocardial infarction (STEMI) after primary percutaneous coronary intervention (PPCI) remains unclear. Recent studies on the association between ST-segment resolution and mortality have given conflicting results. We undertook this study to assess whether ST-segment resolution in electrocardiograms recorded 90-120 min after initiation of PPCI predicts long-term mortality in patients with STEMI. The study included 900 patients with STEMI presenting within the first 24 h after symptom onset who were treated with PPCI. The ST-segment resolution was assessed in electrocardiograms recorded 90-120 min after the first balloon inflation. The ST-segment resolution was dichotomized as follows: < 30% (no resolution), 30% to ≤ 70% (partial resolution) and > 70% (complete resolution). The primary endpoint was five-year mortality. ST-segment resolution was < 30% in 263 (29.0%) patients, between 30% and ≤ 70% in 356 (40.0%) patients and > 70% in 281 (31.0%) patients. There were 62 deaths during the follow-up. In patients with ST-segment resolution < 30%, 30 to ≤ 70% and > 70%, the Kaplan-Meier estimates of mortality were 8.3% (n = 17 deaths), 11.5% (n = 29 deaths) and 6.8% (n = 16 deaths), respectively; unadjusted hazard ratio (HR) = 0.88, 95% confidence interval (CI) 0.46-1.67, p = 0.695 for ST-segment resolution > 70% vs < 30%; adjusted HR = 0.91, 95% CI 0.61-1.33; p = 0.607, for ST-segment resolution > 70% vs ST-segment resolution < 30%. In patients with STEMI undergoing PPCI, ST-segment resolution in electrocardiograms recorded 90-120 min after initiation of PPCI did not predict long-term mortality.

Letter to the Editor Hepatocyte growth factor concentration during the first day of acute coronary syndrome

Hepatocyte growth factor (HGF) can be produced by various cells and elicits multiple biological responses such as motility, proliferation, morphogenesis and survival in a cell type-dependent fashion. Apart from its physiological importance, HGF may contribute to many organ diseases [1–3]. We have already shown that conversely to routinely measured biomarkers of myocardial injury, human HGF (hHGF) increases to high levels in the very early phase of acute coronary syndrome (ACS) and then decreases rapidly during the first 24 h of ACS [4]. As described in our previous article, we measured hHGF concentration only twice, namely at admission and 24 h later [4]. We decided to establish the dynamicity of hHGF level changes on the first day of myocardial injury and to determine the usefulness of its measurement in the case of untimely complications. In 4 patients with ST-segment elevation myocardial infarction (STEMI) and in 2 patients with non ST-segment elevation myocardial infarction (NSTEMI), who were eligible for coronary angiography and, possibly, primary percutaneous coronary intervention (PPCI), hHGF measurements were repeated 10 times during the first day of ACS and once at discharge from hospital (Figure 1). Each subject expressed their informed consent to participate in the study. Patients’ informed consent and the protocol of the study were approved by the Institutional Local Ethics Committee. Patients’ detailed particulars are presented in the Table I. Figure 1 Human HGF concentrations in six patients with ACS Table I Detailed description of six patients with ACS Human HGF was determined in plasma using the Quantikine Elisa kit from R&D Systems, Minneapolis, MN, USA. The mean value of hHGF evaluated in EDTA plasma using the Quantikine Elisa kit and presented in the manufacturer's brochure as a reference value was 787 pg/ml (range: 469-1113 pg/ml). In the first measurement, as illustrated in the Figure 1, a marked increase in hHGF levels was observed in STEMI patients. Very high values (maximally about 20 000 pg/ml) were reduced to almost normal values within 5 h from the first measurement. In NSTEMI patients, even in the first assessment we did not observe very high levels of hHGF, and during the first 24 h of ACS, hHGF levels were stable. Contrary to patients with an uncomplicated acute course of STEMI, 2 patients with serious cardiovascular events in the acute stage of myocardial infarction, namely cardiac arrest and early reocclusion of the coronary artery, revealed a second increase of hHGF levels during the first 24 h of ACS (Figure 1). We have already revealed that during the first 24 h of ACS HGF showed properties comparable with troponin I and N-terminal prohormone B-type natriuretic peptide (NT-proBNP), which are routinely used as markers of ischemic myocardial damage and risk stratification in patients with impaired left ventricular function [4–7]. Troponin I reached peak values and confirmed myocardial necrosis when hHGF levels were already at a normal level [4]. Now, the very high hHGF values were observed in patients admitted within the first 2 h of STEMI presentation (patients 5 and 6) (Figure 1, Table I). In this aspect, the observed changes in hHGF concentrations in the early stage of myocardial infarction are a great advantage of this diagnostic method. The time from the onset of ACS symptoms to treatment, effectiveness of reperfusion therapy measured as grade of flow in the infarct-related artery, and medical therapy applied during PPCI influence the levels of biomarkers [5, 8]. We supposed that in our study hHGF re-elevation was connected with acute complications of ACS. Due to the small number of patients we cannot definitely prove this relationship. We hope that subsequent research will confirm our preliminary observations. In conclusion, we found that: (1) in all our patients the highest hHGF values were observed at admission due to symptoms of acute coronary syndrome, (2) hHGF concentrations were reduced to normal values very quickly (within 5 h from the first measurement), (3) severe complications in the acute stage of STEMI most likely resulted in an additional increase in hHGF levels.

Impact of Body Weight and Extreme Obesity on the Presentation, Treatment, and In-Hospital Outcomes of 50,149 Patients With ST-Segment Elevation Myocardial Infarction: Results From the NCDR (National Cardiovascular Data Registry)

The aim of this study was to assess the impact of extreme (class III) obesity (body mass index [BMI] ≥40 kg/m(2)) on care and outcomes in patients with ST-segment elevation myocardial infarction (STEMI). Although its prevalence is increasing rapidly, little is known about the impact of extreme obesity on STEMI presentation, treatments, complication rates, and outcomes. The relationship between BMI and baseline characteristics, treatment patterns, and risk-adjusted in-hospital outcomes was quantified for 50,149 patients with STEMI from the National Cardiovascular Data Registry (NCDR) ACTION Registry-GWTG. The proportions of patients with STEMI by BMI category were as follows: underweight (BMI <18.5 kg/m(2)) 1.6%, normal weight (18.5 kg/m(2) ≤BMI <25 kg/m(2)) 23.5%, overweight (25 kg/m(2) ≤BMI <30 kg/m(2)) 38.7%, class I obese (30 kg/m(2) ≤BMI <35 kg/m(2)) 22.4%, class II obese (35 kg/m(2) ≤BMI <40 kg/m(2)) 8.7%, and class III obese 5.1%. Extreme obesity was associated with younger age at STEMI presentation (median age 55 years for class III obese vs. 66 years for normal weight); a higher prevalence of diabetes, hypertension, and dyslipidemia; a lower prevalence of smoking; and less extensive coronary artery disease and higher left ventricular ejection fraction. Process-of-care measures were similar across BMI categories, including the extremely obese. Using class I obesity as the referent, risk-adjusted in-hospital mortality rates were significantly higher only for class III obese patients (adjusted odds ratio: 1.64; 95% confidence interval: 1.32 to 2.03). Patients with extreme obesity present with STEMI at younger ages and have less extensive coronary artery disease, better left ventricular systolic function, and similar processes and quality of care. Despite these advantages, extreme obesity remains independently associated with higher in-hospital mortality.

Reperfusion Paradox in ST-Segment Elevation Myocardial Infarction

A transformation in ST-segment elevation myocardial infarction (STEMI) care in the United States has unfolded. It asserts superior reperfusion with primary percutaneous coronary intervention (PPCI) over fibrinolysis on the basis of studies showing the former method to be superior for reperfusion of patients with STEMI. Although clear benefit has resulted from national programs directed toward achieving shorter times to PPCI in facilities with around-the-clock access, most patients present to non-PPCI hospitals. Because delay to PPCI for most patients with STEMI presenting to non-PPCI centers remains outside current guidelines, many are denied benefit from pharmacologic therapy. This article describes why this approach creates a treatment paradox in which more effort to improve treatment for patients with PPCI for acute STEMI often leads to unnecessary avoidance and delay in the use of fibrinolysis. Recent evidence confirms the unfavorable consequences of delay to PPCI and that early prehospital fibrinolysis combined with strategic mechanical co-interventions affords excellent outcomes. The authors believe it is time to embrace an integrated dual reperfusion strategy to best serve all patients with STEMI.

One-Year Clinical Outcome of Interventionalist- Versus Patient-Transfer Strategies for Primary Percutaneous Coronary Intervention in Patients With Acute ST-Segment Elevation Myocardial Infarction

Traditional reperfusion options for patients with acute ST-segment elevation myocardial infarction (STEMI) presenting to non-primary percutaneous coronary intervention (PPCI)-capable hospitals generally include onsite fibrinolytics or emergency transfer for PPCI. A third option, involving interventionalist transfer, was examined in the REVERSE-STEMI study. A total of 334 patients with acute STEMI who presented to 5 referral hospitals with angiographic facilities but without interventionalists qualified for PPCI were randomized to receive PPCI with either an interventionalist- (n=165) or a patient-transfer (n=169) strategy. The primary end point of door-to-balloon (D2B) time and secondary end points of left ventricular ejection fraction and major adverse cardiac events (MACE) at 1-year clinical follow-up were compared between the 2 groups. Compared with the patient-transfer strategy, the interventionalist-transfer strategy resulted in a significantly shortened D2B time (median, 92 minutes versus 141 minutes; P<0.0001), with more patients having first balloon angioplasty within 90 minutes (21.2% versus 7.7%, P<0.001). This treatment strategy also was associated with higher left ventricular ejection fraction (0.60±0.07 versus 0.57±0.09, P<0.001) and improved 1-year MACE-free survival (84.8% versus 74.6%, P=0.019). Multivariate Cox proportional hazards modeling revealed that the interventionalist-transfer strategy was an independent factor for reduced risk of composite MACE (hazard ratio, 0.63; 95% CI, 0.45 to 0.88; P=0.003). The interventionalist-transfer strategy for PPCI may be effective in improving the care of patients with STEMI presenting to a non-PPCI-capable hospital, particularly in a congested cosmopolitan region where patient transfers could be prolonged.

Effects of aspiration thrombectomy on necrosis size and ejection fraction after transradial percutaneous coronary intervention in acute ST‐elevation myocardial infarction

The use of routine aspiration thrombectomy in primary percutaneous coronary intervention (PCI) remains controversial. Patients in the EArly Discharge after Transradial Stenting of CoronarY Arteries in Acute Myocardial Infarction (n = 105) study were treated with aspirin, clopidogrel, and abciximab within 6 hr of symptoms onset. Operators were allowed to use 6 Fr Export aspiration catheter at their discretion. In this observational analysis, we compared acute and late results in patients treated with and without thrombectomy using cardiac biomarkers, angiographic, cardiovascular magnetic resonance (CMR), and clinical parameters. Patients in the thrombectomy group (n = 44) had longer symptoms to balloon time (196 ± 86 min vs. 164 ± 62, P = 0.039) and higher incidence of preprocedural TIMI flow grade 0 or 1 (84% vs. 64%, P = 0.028). Following PCI, both groups had similar incidence of TIMI flow grade 3 (93 vs. 92%, P = 0.73) and myocardial blush grade 2 or 3 (80 vs. 77%, P = 0.86), respectively. Patients in thrombectomy group had significantly higher post-PCI maximum values of creatine kinase-MB (P = 0.0007) and troponin T (P = 0.0010). Accordingly, post-PCI myocardial necrosis by CMR was higher (P = 0.0030) in patients in the thrombectomy group. At 6-month follow-up, necrosis size remained higher (20.7% ± 13.3% vs. 13.5% ± 11.1%, P = 0.012) in the thrombectomy group. Ejection fraction at 6 months was 65% ± 9% in patients in thrombectomy group compared to 70% ± 11% in patients without (P = 0.070). Results were not affected by initial TIMI flow or symptoms to balloon time. Clinical events remained comparable in both groups at 12 months follow-up. In patients with ST-segment elevation myocardial infarction presenting within 6 hr of symptoms and undergoing primary angioplasty with maximal antiplatelet therapy, acute and late results did not suggest significant benefit for additional aspiration thrombectomy, irrespective of initial TIMI flow or total ischemic time.

Heparin or enoxaparin anticoagulation for primary percutaneous coronary intervention

The aim of this study was to compare efficacy and safety outcomes among patients receiving enoxaparin or unfractionated heparin (UFH) while undergoing percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI). Primary PCI (pPCI) for ST elevation has traditionally been supported by UFH. The low molecular weight heparin enoxaparin may provide better outcomes when used for pPCI. Consecutive eligible patients (580) undergoing pPCI enrolled in the prospective electronic Pitié-Salpêtrière registry of ischemic coronary syndromes (e-PARIS) registry were grouped according to whether they received UFH or enoxaparin as the sole anticoagulant. Logistic regression modeling, propensity-weighted adjustment, and sensitivity analyses were used to evaluate efficacy and safety endpoints for enoxaparin vs. UFH. Enoxaparin was administered to 346 patients and UFH to 234 without ACT or anti-Xa guided dose adjustment. PCI was performed through the radial artery in 90%, with frequent (75%) use of GPIIb/IIIa antagonists. Patients receiving enoxaparin were more likely to be therapeutically anticoagulated during the procedure (68% vs. 50%, P < 0.0001) and were less likely to experience death or recurrent myocardial infarction (MI) in hospital (adjusted OR 0.28 95% CI (0.12-0.68) or by 30 days (adjusted OR 0.35 95% CI 0.16-0.81). All cause mortality was also reduced in hospital (adjusted OR 0.32, 95% CI (0.12-0.85) and to 30 days (adjusted OR 0.40 95% CI 0.17-0.99). Other ischemic endpoints were similarly reduced with enoxaparin. Thrombolysis in myocardial infarction (TIMI) major bleeding events were numerically fewer among patients receiving enoxaparin (1.2% vs. 2.6%, P = 0.2). In patients with STEMI presenting for PCI, enoxaparin was associated with a reduction in all ischemic complications, more frequent therapeutic anticoagulation, and no increase in major bleeding when compared against unfractionated heparin. © 2010 Wiley-Liss, Inc.

Effect of Aspiration Thrombectomy on Microvascular Dysfunction in ST-Segment Elevation Myocardial Infarction With an Elevated Neutrophil Count

Background and ObjectivesAspiration thrombectomy (AT) during primary percutaneous coronary intervention (PCI) is an effective adjunctive therapy for ST-segment elevation myocardial infarction (STEMI). An elevated neutrophil count in STEMI is associated with microvascular dysfunction and adverse outcomes. We evaluated whether AT can improve microvascular dysfunction in patients with STEMI and an elevated neutrophil count.Subjects and MethodsSeventy patients with STEMI undergoing primary PCI from August 2007 to February 2009 in our institution were classified by tertiles of neutrophil count on admission (<5,300/mm3, 5,300-7,600/mm3, and >7,600/mm3). The angiographic outcome was post-procedural thrombolysis in myocardial infarction (TIMI) flow grade. Microvascular dysfunction was assessed by TIMI myocardial perfusion (TMP) grade and ST-segment resolution on electrocardiography 90 minutes after PCI. The clinical outcome was major adverse cardiac event (MACE), defined as cardiac death, re-infarction, and target lesion revascularization at 9 months.ResultsThere were no significant differences in the clinical characteristics and pre- and post-procedural TIMI flow grades between the neutrophil tertiles. As the neutrophil count increased, a lower tendency toward TMP grade 3 (83% vs. 52% vs. 54%, p=0.06) and more persistent residual ST-segment elevation (>4 mm: 13% vs. 26% vs. 58%, p=0.005) was observed. The 9-month MACE rate was similar between the groups. On subgroup analysis of AT patients (n=52) classified by neutrophil tertiles, the same tendency toward less frequent TMP grade 3 (77% vs. 56% vs. 47%, p=0.06) and persistent residual ST-segment elevation (>4 mm: 12% vs. 28% vs. 53%, p=0.05) was observed as neutrophil count increased.ConclusionA higher neutrophil count at presentation in STEMI is associated with more severe microvascular dysfunction after primary PCI, which is not improved with AT.

Primary percutaneous coronary intervention in ‘early’ latecomers with ST-segment elevation acute myocardial infarction: the role of the infarct-related artery status

A high proportion of patients with ST-segment elevation myocardial infarction (STEMI) are evaluated more than 12 h after symptom onset. In this setting, current guidelines suggest that mechanical reperfusion should be considered for patients with clinical and/or electrocardiographic evidence of ongoing ischaemia, re-infarction, cardiogenic shock, haemodynamic instability, or documented ejection fraction less than 40% and serious ventricular arrhythmias. Moreover, some adjunctive aspects like the stuttering course of acute myocardial infarction, the chance of an existing coronary collateral circulation, the ischaemic preconditioning and the infarct-related artery patency should be taken into consideration for patients with STEMI presenting from 12 to 72 h after symptom onset. These patients are known as 'early' latecomers. The aim of the present review is to summarize the current knowledge of the pathophysiology related to this topic and to suggest some new indications for primary percutaneous coronary intervention in 'early' latecomers.

Door-to-Balloon Times Under 90 Min Can Be Routinely Achieved for Patients Transferred for ST-Segment Elevation Myocardial Infarction Percutaneous Coronary Intervention in a Rural Setting

The purpose of this study was to demonstrate the feasibility of routine transfer of ST-segment elevation myocardial infarction (STEMI) patients to achieve percutaneous coronary intervention (PCI) in less than 90 min from presentation. Many PCI hospitals have achieved routine door-to-balloon times under 90 min for patients with STEMI presenting directly to the hospital. However, few patients transferred from a non-PCI center undergo PCI within 90 min of presentation. Our rural PCI hospital implemented a program in 2005 for rapid triage, transfer, and treatment of STEMI patients and made additional improvements in 2006 and 2007. Intervals between milestones in the STEMI triage/transfer/treatment process were assessed before and after implementation of the program. During the 5-year study period, 676 patients with 687 STEMIs were transferred from 19 community hospitals and underwent PCI. Median door-to-balloon time decreased from 189 min to 88 min (p < 0.001). The time intervals reflecting efficiency of the referring hospitals, transfer services, and PCI hospital all significantly improved. In 2008, median door-to-balloon times were <90 min for 6 of the 7 most frequently referring hospitals. Delays during off-hours presentation in 2004 were abolished after the program was implemented in 2005. In-hospital mortality decreased from 6% before to 3% after implementation of the program. In multivariate modeling, presentation before initiation of the STEMI program predicted increased risk of in-hospital mortality (odds ratio: 3.74, 95% confidence interval: 1.22 to 11.51, p = 0.021). A program of rapid triage, transfer, and treatment of STEMI patients presenting to non-PCI hospitals can reduce in-hospital mortality and produce progressive improvements in door-to-balloon time such that median door-to-balloon times under 90 min are feasible.

Reperfusion by Primary Percutaneous Coronary Intervention in Patients With ST-Segment Elevation Myocardial Infarction Within 12 to 24 Hours of the Onset of Symptoms (from a Prospective National Observational Study [PL-ACS

The aim of the present study was to investigate whether reperfusion by primary percutaneous coronary intervention (PCI) improves 12-month survival in late presenters with ST-segment elevation myocardial infarction (STEMI). We analyzed 2,036 patients with STEMI presenting 12 to 24 hours from onset of symptoms, without cardiogenic shock or pulmonary edema and not reperfused by thrombolysis, of 23,517 patients with STEMI enrolled in the Polish Registry of Acute Coronary Syndromes from June 2005 to August 2006. An invasive approach was chosen in 910 (44.7%) of late presenters and 92% of them underwent reperfusion by PCI. Patients with an invasive approach had lower mortality after 12 months than patients with a conservative approach (9.3% vs 17.9%, p <0.0001). The benefit of an invasive approach was also observed after multivariate adjustment with a relative risk 0.73 for 12-month mortality (95% confidence interval 0.56 to 0.96) and in a subpopulation of patients selected by a propensity-score matching procedure with an adjusted relative risk 0.73 for 12-month mortality (0.58 to 0.99). In conclusion, almost 1/2 of late presenters with STEMI were considered eligible for reperfusion by primary PCI. These patients had a lower 12-month mortality rate than they would have had if they had been treated conservatively, which supports the idea of late reperfusion in STEMI. However, whether all late presenters with STEMI should be treated invasively remains unanswered. Nevertheless, until a randomized trial is undertaken, late presenters with STEMI could be considered for reperfusion by primary PCI.

The Outcomes of Emergency Pharmacist Participation during Acute Myocardial Infarction

BackgroundCurrent guidelines recommend door-to-balloon times of 90min or less for patients presenting to the emergency department (ED) with ST-segment elevation myocardial infarction (STEMI). ObjectivesTo determine if a clinical pharmacist for the ED (EPh) is associated with decreased door/diagnosis-to-cardiac catheterization laboratory (CCL) time and decreased door-to-balloon time. MethodsA retrospective observational cohort study of ED patients with STEMI requiring urgent cardiac catheterization was conducted. Blinded data collection included timing of ED and CCL arrival, diagnostic electrocardiogram (ECG), and balloon angioplasty. For cases diagnosed after ED arrival, diagnosis time was substituted for door time. Diagnosis was the time ST elevations were evident on serial ECG. EPh present and not-present groups were compared. During the study period there were two EPhs and presence was determined by their scheduled time in the ED. Univariate and multivariate analyses was used to detect differences. ResultsMultivariate analysis of 120 patients, controlled for CCL staff presence and arrival by pre-hospital services, determined that EPh presence is associated with a mean 13.1-min (95% confidence interval [CI] 6.5–21.9) and 11.5-min (95% CI 3.9–21.5) decrease in door/diagnosis-to-CCL and door-to-balloon times, respectively. Patients were more likely to achieve a door/diagnosis-to-CCL time≤30min (odds ratio [OR] 3.1, 95% CI 1.3–7.8) and≤45min (OR 2.9, 95% CI–1.0, 8.5) and a door-to-balloon time≤90min (OR 1.9, 95% CI 0.7–5.5) more likely when the EPh was present. ConclusionsEPh presence during STEMI presentation to the ED is independently associated with a decrease in door/diagnosis-to-CCL and door-to-balloon times.

Intracoronary Compared to Intravenous Abciximab and High-Dose Bolus Compared to Standard Dose in Patients With ST-Segment Elevation Myocardial Infarction Undergoing Transradial Primary Percutaneous Coronary Intervention: a Two-by-Two Factorial Placebo-Controlled Randomized Study

Platelet aggregation inhibition (PAI) of > or =95% has been associated with improved outcomes after percutaneous coronary intervention (PCI) and glycoprotein IIb/IIIa inhibitor treatment. A greater thrombotic burden in acute ST-segment elevation myocardial infarction (STEMI) might require higher doses and/or intracoronary delivery of glycoprotein IIb/IIIa inhibitors to achieve optimal PAI. Using a 2 x 2 factorial placebo-controlled design, 105 patients with STEMI who had been referred for primary PCI within 6 hours of symptom onset were randomized to intracoronary (IC) or intravenous (IV) delivery of an abciximab bolus at a standard dose (0.25 mg/kg) or high dose (> or =0.30 mg/kg) of abciximab. The primary end point was PAI measured at 10 minutes after the bolus of abciximab. Secondary end points included the acute and 6-month outcomes using angiographic parameters, cardiac biomarkers, cardiovascular magnetic resonance imaging, and clinical end points. At 10 minutes after the bolus, the proportion of patients with > or =95% PAI was not different between the IC and IV groups (53% vs 54%, p = 1.00) nor between the high-dose and standard-dose bolus groups (56% vs 51%, p = 0.70). Acutely, the angiographic myocardial blush grades, peak release of cardiac biomarkers, necrosis size, myocardial perfusion, and no reflow as assessed by magnetic resonance imaging, and clinical end points were similar between the groups and did not suggest a benefit for IC compared to IV or high-dose versus standard-dose bolus of abciximab. No increase occurred in bleeding complications with the high-dose bolus or IC delivery. The clinical, angiographic and cardiac magnetic resonance imaging outcomes at 6 and 12 months were similar between the 4 groups. In conclusion, in patients with STEMI presenting with symptom onset <6 hours and undergoing transradial primary PCI, PAI remained suboptimal, despite a higher dose bolus of abciximab. A higher dose bolus or IC delivery of abciximab bolus was not associated with improved acute or late results compared to the standard IV dosing and administration.

Does on‐ versus off‐hours presentation impact in‐hospital outcomes of ST‐segment elevation myocardial infarction patients transferred to a tertiary care center?

To determine whether in-hospital outcome differs for transferred patients with ST-segment elevation myocardial infarction (STEMI) presenting during business (ON) hours vs. after (OFF) hours. Door-to-device (DTD) time is a prognostic factor in patients with STEMI and is longer during OFF hours. However, the in-hospital mortality is controversial. This registry study included 786 consecutive patients with STEMI referred for primary percutaneous coronary intervention to a tertiary care center with an on-site cardiac catheterization team 24 hrs a day/7 days (24/7) a week. ON hours were defined as weekdays 8 a.m. to 5 p.m., while OFF hours were defined as all other times, including holidays. The primary outcomes were in-hospital death, reinfarction, and length of stay (LOS). ON hours (29.5%, n = 232) and OFF hours (70.5%, n = 554) groups had similar demographic and baseline characteristics. A significantly higher proportion of patients presenting ON hours had a DTD time ≤120 min compared to OFF hours patients (32.6% vs. 22.1%, P = 0.007). The rates of in-hospital death (8.2% vs. 6%), reinfarction (0% vs. 1.1%), and mean LOS (5.7 ± 6 vs. 5.7 ± 5) were not significantly different in the ON vs. OFF hours groups, all P = nonsignificant. In a tertiary care center with an on-site cardiac catheterization team 24/7, there are no differences in in-hospital outcomes of transferred patients with STEMI during ON vs. OFF hours.

Factors Contributing to Door-to-Balloon Times of ≤90 Minutes in 97% of Patients with ST-Elevation Myocardial Infarction: Our One-Year Experience with a Heart Alert Protocol

Prompt percutaneous coronary intervention (PCI) for patients with ST-segment elevation myocardial infarction (STEMI) can significantly reduce mortality and morbidity, although its effectiveness may be limited by delays in delivery. In March 2008, our hospital implemented a Heart Alert protocol to rapidly identify and treat patients with STEMI presenting to our Emergency Department (ED) with PCI, using strategies previously described to reduce door-to-balloon times. Before the Heart Alert protocol start date, patients with STEMI presenting to our ED were treated with thrombolysis. We evaluated data from patients with STEMI after one year of use of our Heart Alert protocol to determine protocol success on the basis of the percentage of patients for whom the recommended door-to-balloon times of ≤90 minutes were met. We examined factors involved in implementation of the protocol that contributed to these results. We conducted a retrospective data and chart review for patients in the ED with STEMI who underwent PCI after a Heart Alert protocol activation between March 17, 2008, and March 17, 2009. During the study period, our staff met the recommended door-to-balloon time of ≤90 minutes (mean door-to-balloon time, 57.3 ± 17.6 minutes) for 70 of 72 patients (97%) presenting to our ED with STEMI. Sixty-five of the 72 patients (90.3%) survived to hospital discharge. Initiation of a Heart Alert protocol at our hospital resulted in achievement of door-to-balloon times of ≤90 minutes for 97% of patients with STEMI. This achievement was obtained through careful preparation, training, and interdepartmental collaboration and occurred despite immediate conversion from a previous thrombolytic protocol.

Outcomes Among Patients With ST-Segment–Elevation Myocardial Infarction Presenting to Interventional Hospitals With and Without On-Site Cardiac Surgery

Primary percutaneous coronary intervention (pPCI) is the preferred reperfusion strategy for patients with ST-segment-elevation myocardial infarction (STEMI). The quality of care and safety and efficacy of pPCI at hospitals without on-site open heart surgery (No-OHS hospitals) remains an area of active investigation. The National Registry of Myocardial Infarction enrolled 58 821 STEMI patients from 214 OHS hospitals (n=54 076) and 52 No-OHS hospitals (n=4745) with PCI capabilities from 2004 to 2006. Patients presenting to OHS hospitals had substantially lower in-hospital mortality (7.0% versus 9.8%, P<0.001) and were more likely to receive any form of acute reperfusion therapy (80.8% versus 70.8%, P<0.001). Patients who presented to OHS hospitals were more likely to receive guideline recommended medications within 24 hours of arrival. In a propensity score model matching for patient characteristics and transfer status, in-hospital mortality remained significantly lower among patients presenting to OHS hospitals (7.2% versus 9.3%, P=0.025). When this model was further adjusted for differences in the use of acute reperfusion therapy, medications administered within 24 hours and hospital characteristics, the mortality difference was of borderline significance (hazard ratio, 0.87; 95% CI, 0.75 to 1.01; P=0.067). When the propensity score analysis was restricted to patients who underwent pPCI, there was no significant difference in mortality (3.8% versus 3.3%, P=0.44). STEMI patients presenting to No-OHS hospitals have substantially higher mortality, are less likely to receive guideline recommended medications within 24 hours, and are less likely to undergo acute reperfusion therapy, although this difference was of borderline significance after adjusting for hospital and treatment variables. There was no difference in mortality among patients undergoing pPCI.

Outcomes Among Patients With Non–ST-Segment Elevation Myocardial Infarction Presenting to Interventional Hospitals With and Without On-Site Cardiac Surgery

The goals of this analysis were: 1) to evaluate outcomes among non-ST-segment elevation myocardial infarction (NSTEMI) patients presenting to hospitals with on-site cardiac surgery (OHS hospitals) and without on-site cardiac surgery (No-OHS hospitals); and 2) to specifically examine outcomes among the subset of NSTEMI patients undergoing percutaneous coronary intervention (PCI). Whether backup cardiac surgery improves outcomes among NSTEMI patients or is simply a marker of better adherence to guideline recommendations is unknown. The NRMI (National Registry of Myocardial Infarction) enrolled 100,071 NSTEMI patients from 2004 to 2006. Outcomes were evaluated in the population as a whole and in propensity-matched analyses in the entire population and in the subset of patients undergoing PCI. In-hospital mortality was significantly lower at OHS hospitals (5.0% vs. 8.8%, p < 0.001). Patients presenting to OHS hospitals were significantly more likely to receive aspirin, beta-blockers, and statins (p < 0.05 for all) and to undergo PCI (38.4% vs. 14.1%, p < 0.001). In the propensity-matched model, the difference in mortality remained significant (5.9% vs. 8.5%, p < 0.001). After adjusting for differences in medications administered within 24 h of arrival and hospital characteristics, the difference in mortality was nearly attenuated (hazard ratio: 0.89, 95% confidence interval: 0.79 to 1.00, p = 0.050). When the propensity-matched model was restricted to patients undergoing PCI, there was no significant difference in mortality (1.3% vs. 1.0%, p = 0.51). NSTEMI patients presenting to No-OHS hospitals have significantly higher mortality. This appears to be due to both modifiable (lower use of guideline-recommended medications) and nonmodifiable factors (hospital size, myocardial infarction volume). In a propensity-matched analysis of patients undergoing PCI for NSTEMI, there was no significant difference in mortality.

Requirement for Emergent Coronary Artery Bypass Surgery Following Percutaneous Coronary Intervention in the Stent Era

Performance of percutaneous coronary intervention (PCI) at centers without cardiothoracic surgery is a contentious issue. Although this practice allows greater access to care, there are safety concerns. The aim was to assess the requirement for emergent coronary artery bypass grafting (CABG) after PCI and characterize patients at highest risk using independent predictors. The study population consisted of 21,957 unselected patients who underwent PCI from August 1994 (Food and Drug Administration stent approval) to January 2008 at a single medical center. Patients requiring emergent CABG (defined as within 24 hours of the index procedure) were identified. Logistic regression analysis was performed to assess for independent correlates of emergent CABG. Emergent CABG was required in 90 patients (cumulative incidence 0.41%). Indications for CABG included triple-vessel disease, dissection, acute closure, perforation, and failure to cross. These patients had significantly higher in-hospital cardiac death rates (7.8% vs 0.7%; p <0.01) and higher rates of Q-wave myocardial infarction, neurologic events, and renal insufficiency. Independent correlates of emergent CABG after PCI were acute ST-segment elevation myocardial infarction presentation, cardiogenic shock, triple-vessel disease, and type C lesion. Risk assessment based on these predictors identified 0.3% of the patient population to have a 9.3% cumulative incidence of emergent CABG. In conclusion, the need for emergent CABG after PCI in the stent era was low and was associated with poor in-hospital outcomes. Risk was nonuniform, with 0.3% of the study population, characterized by acute presentation and complex coronary disease, at heightened risk of emergent surgery.

Angioplasty Strategies in ST-Segment–Elevation Myocardial Infarction

Cardiovascular disease is the most common cause of mortality in most developed nations; ≈838 000 in-hospital discharges in the United States in 2005 were for acute myocardial infarction, 29% to 47% of which were acute ST-segment-elevation myocardial infarction (STEMI).1 The case fatality rate of STEMI has fallen dramatically in the last 3 decades, in part because of the widespread use of reperfusion therapy.1–4 STEMI is in most cases due to rupture of an inflamed thin-capped fibroatheroma containing a lipid-rich necrotic core with superimposed secondary thrombosis resulting in coronary artery occlusion.5,6 From the seminal demonstration by Reimer et al7 that canine coronary occlusion results in a several-hour wave front of necrosis spreading from the subendocardial to the subepicardial myocardium arose the hypothesis that timely restoration of flow in the occluded coronary artery would salvage jeopardized myocardium and enhance survival. Effective reperfusion in STEMI can be achieved by either fibrinolytic therapy or primary percutaneous coronary intervention (PCI) without antecedent fibrinolysis (also generally known as primary angioplasty). Fibrinolysis and PCI also may be combined in a variety of ways, depending on the timing of PCI after fibrinolytic administration, the clinical condition of the patient, and whether PCI is applied routinely or selectively after lytic therapy. Randomized trials have collectively demonstrated enhanced survival and freedom from major adverse cardiovascular events with primary PCI compared with fibrinolysis, and as a result, the expeditious performance of primary PCI has become the preferred reperfusion modality for patients with STEMI presenting at appropriately equipped centers. The introduction of new devices such as bare metal stents (BMS) and drug-eluting stents (DES) and novel potent antiplatelet and antithrombotic agents have transformed the interventional approach to the patient with STEMI. Important studies have been completed that have addressed previously unsettled issues such as the importance of time …

Angioplasty Strategies in ST-Segment–Elevation Myocardial Infarction

As reviewed in part I of this report,1 primary PCI without antecedent fibrinolytic therapy has become widely accepted as the preferred reperfusion modality for patients with ST-segment–elevation myocardial infarction (STEMI) presenting at suitably equipped tertiary facilities. However, primary percutaneous coronary intervention (PCI) is not offered at ≥50% of US hospitals, and many of those that do are unable to offer primary PCI as an around-the-clock service. Primary PCI also is less widely available in many other countries than in the United States. Thus, fibrinolytic therapy continues to be administered to many patients with STEMI.2,3 Given the relatively low rates of successful reperfusion with fibrinolysis,4,5 revascularization often is required afterward, the indications for and outcomes of which are critically evaluated here. The impact of individual operator and institutional volumes on PCI outcomes is reviewed. Evidence-based recommendations for selecting among the various reperfusion therapy options are then offered for the patients with STEMI presenting at centers with and without interventional capabilities, with distinctions drawn where the evidence-based recommendations in this article differ substantially from recently updated task force guidelines of the American College of Cardiology (ACC) and American Heart Association (AHA).5 Finally, recent and ongoing investigations to further improve outcomes after catheter-based reperfusion therapy are summarized. PCI after fibrinolytic therapy in STEMI may be performed in a variety of settings: (1) rescue PCI after failed fibrinolysis in patients with ongoing symptoms, myocardial injury, or persistent coronary occlusion, typically initiated within 60 to 120 minutes after fibrinolytic administration; (2) immediate PCI (also known as facilitated PCI), performed within several hours after fibrinolytic administration, regardless of whether clinical or ECG evidence of ongoing myocardial injury is present; (3) delayed routine PCI, in which patients who are stable for several days after fibrinolytic administration undergo angiography and PCI, regardless of the …