Transfer for urgent percutaneous coronary intervention early after thrombolysis for ST-elevation myocardial infarction: the TRANSFER-AMI pilot feasibility study

Primary Percutaneous Coronary Intervention and Application of the Pharmacoinvasive Approach Within ST-Elevation Myocardial Infarction Care Networks

The management of acute ST-elevation myocardial infarction (STEMI) has transitioned from observation and reactive treatment of hemodynamic and arrhythmic complications to accelerated reperfusion and application of evidence-based treatment to minimize morbidity and mortality. International research established the importance of timely reperfusion therapy and the application of fibrinolysis, primary percutaneous coronary intervention (PCI), and subsequent development of the pharmacoinvasive approach. Clinician thought leaders developed and investigated comprehensive systems of care to optimize the outcomes of patients with STEMI, with a key focus in Canada being the integration of prehospital paramedics in diagnosis, triage, and treatment. This article will review highlights of these interventions and identify future challenges and opportunities in STEMI patient care.

Transfer of Patients with ST Elevation Myocardial Infarction for Primary Percutaneous Coronary Intervention During Ordinary & Pandemic Times Position statement of the Saudi Arabian Cardiac Intervention Society

Primary percutaneous coronary intervention is the most effective therapy in the management of acute ST Elevation Myocardial Infarction. Evidence recommends keeping the period from symptom onset to reperfusion to a minimum in order to preserve left ventricular function, improve outcome and reduce mortality. This position statement describes the recommendations of the Saudi Arabian Cardiac Intervention Society for optimal conditions and timing for the acute management of patients presenting with ST Elevation Myocardial Infarction during ordinary and pandemic times.

Early vs Late Coronary Angiography and Intervention Following Thrombolytic Therapy; a Cohort Study

INTRODUCTION

The precise time of using percutaneous coronary intervention (PCI) after fibrinolytic therapy for maximum efficiency and minimum side effects is still undetermined. Therefore, the present study was designed to compare the outcome of myocardial infarction (MI) patients who underwent surgical intervention (angiography and PCI) within 48 hours of thrombolytic therapy or after that.

METHODS

The present study is a prospective cohort study aiming to compare the occurrence of no-reflow phenomenon, unstable angina, bleeding during intervention, and one month major adverse cardiac outcomes (recurrent MI, need for repeating surgical intervention, and mortality) between MI patents undergoing surgical intervention within the first 48 hours of or after 48 hours of thrombolytic therapy.

RESULTS

90 patients with the mean age of 54.97 ± 10.54 were studied (86.67% male). 50 (56%) patients underwent surgical intervention within 48 hours and 40 (44%) after that. The 2 groups were not significantly different regarding baseline characteristics. No-reflow phenomenon in the < 48 hours group was about twice the > 48 hours group (OR = 0.35; 95% confidence interval: 0.14 - 0.92; p = 0.03), other outcomes were not significantly different. No case of mortality was seen in the 1 month follow up.

CONCLUSION

Based on the results of the present study, it seems that no-reflow phenomenon rate is significantly lower in patients undergoing surgical intervention after 48 hours of fibrinolytic therapy. The difference between the two groups regarding prevalence of major adverse cardiac outcomes was not statistically significant.

Repatriation to referral hospital after reperfusion of STEMI patients transferred for primary percutaneous coronary intervention: Insights of a Canadian regional STEMI care system

BACKGROUND

In regional systems of ST-segment elevation myocardial infarction (STEMI) care, patients presenting to hospitals without percutaneous coronary intervention (PCI) are transferred to PCI-capable hospitals for primary PCI. Repatriation, a practice whereby such patients are transferred back to non-PCI referral hospitals after reperfusion is prevalent in many jurisdictions, yet little is known of this practice and its safety.

METHODS

We studied 979 consecutive STEMI patients transported from the emergency department and catchment area of two non-PCI hospitals in Ontario, Canada to a regional PCI-hospital for primary PCI between January 2008 and June 2014. Logistic regression modeling was performed to determine factors associated with delayed repatriation beyond 24 hours and to evaluate the association between repatriation and index-admission mortality.

RESULTS

Eight hundred and fifteen (83.2%) patients were repatriated with 524 (65.2%) patients repatriated within 24 hours. Factors independently associated with delayed repatriation included systolic blood pressure (OR 1.03 per 5 mmHg decrease, 95% CI 1.01-1.06, P= .04), requirement for mechanical ventilation (OR 24.9, 95% CI 5.4-115.3, P< .0001), ventricular arrhythmia (OR 3.0, 95% CI 1.3-6.6, P= .01), infarct-related artery (P= .03), final TIMI flow grade (P= .01) and access-site complications (OR 2.36, 95% CI 1.04-5.4, P= .04). After repatriation, 9 (1.3%) patients returned to the PCI-hospital for urgent care, and 16 (2.0%) died during index-admission. After adjustment, repatriation was not associated with increase in index-admission mortality (adjusted OR 0.46, 95% CI 0.16-1.32, P= .15).

CONCLUSIONS

In a regional STEMI care system in Ontario, Canada, patients are routinely repatriated to non-PCI hospitals after primary PCI. This practice was associated with very low and acceptable rate of return to the PCI-hospital during index-admission without an adverse impact on short-term outcomes.

Clinical Outcomes of Early Repatriation for Patients With ST-Segment Elevation Myocardial Infarction: A Propensity-Matched Analysis

BACKGROUND

Because of limitations on hospital resources, patients with ST-elevation myocardial infarction (STEMI) who undergo successful primary percutaneous coronary intervention (PCI) are often repatriated to non-PCI centres. However, the safety of this practice is not clear. Our objective was to evaluate the safety of early repatriation of STEMI patients after PCI to a non-PCI centre, compared with ongoing treatment at the PCI centre.

METHODS

Consecutive STEMI patients, who received primary PCI at 1 of 4 PCI hospitals in Toronto, Canada between 2010 and 2012 were identified. Patients with shock or who died within 24 hours of presentation were excluded. Outcomes of interest were all-cause mortality and readmission for recurrent myocardial infarction (MI) at 1 year. To account for confounding because of the observational nature of our data, propensity score-matched pairs of patients who were repatriated vs nonrepatriated were identified.

RESULTS

Using the propensity score, 430 well matched pairs were identified, representing our cohort. There was no significant difference between repatriated and nonrepatriated groups in 1-year mortality (repatriated: 6.7%, nonrepatriated: 5.6%, hazard ratio, 1.18; 95% confidence interval, 0.69-2.03; P = 0.545). The 1-year readmission rates for MI were significantly greater for the repatriated group compared with the nonrepatriated group (repatriated: 12.1%; nonrepatriated: 5.8%; hazard ratio, 2.09; 95% confidence interval, 1.30-3.36; P = 0.002).

CONCLUSIONS

A strategy of early repatriation of STEMI patients was associated with a greater rate of readmission for MI. Our study raises questions regarding the safety of an early repatriation strategy that merit further research.

Comparison of the efficacy of pharmacoinvasive management for ST-segment elevation myocardial infarction in smokers versus non-smokers (from the Trial of Routine Angioplasty and Stenting After Fibrinolysis to Enhance Reperfusion in Acute Myocardial Infarction)

Compared with non-smokers, cigarette smokers with ST-segment elevation myocardial infarctions derive greater benefit from fibrinolytic therapy. However, it is not known whether the optimal treatment strategy after fibrinolysis differs on the basis of smoking status. The Trial of Routine Angioplasty and Stenting After Fibrinolysis to Enhance Reperfusion in Acute Myocardial Infarction (TRANSFER-AMI) randomized patients with ST-segment elevation myocardial infarctions to a routine early invasive (pharmacoinvasive) versus a standard (early transfer only for rescue percutaneous coronary intervention or delayed angiography) strategy after fibrinolysis. The efficacy of these strategies was compared in 1,051 patients on the basis of their smoking status. Treatment heterogeneity was assessed between smokers and non-smokers, and multivariable analysis was performed to evaluate for an interaction between smoking status and treatment strategy after adjusting for baseline Global Registry of Acute Coronary Events (GRACE) risk score. Smokers (n=448) were younger, had fewer cardiovascular risk factors, and had lower GRACE risk scores. They had a lower rate of the primary composite end point of 30-day mortality, reinfarction, recurrent ischemia, heart failure, or cardiogenic shock and fewer deaths or reinfarctions at 6 months and 1 year. Smoking status was not a significant predictor of either primary or secondary end points in multivariable analysis. Pharmacoinvasive management reduced the primary end point compared with standard therapy in smokers (7.7% vs 13.6%, p=0.04) and non-smokers (13.1% vs 19.7%, p=0.03). Smoking status did not modify treatment effect on any measured outcomes (p>0.10 for all). In conclusion, compared with non-smokers, current smokers receiving either standard or early invasive management of ST-segment elevation myocardial infarction after fibrinolysis have more favorable outcomes, which is likely attributable to their better baseline risk profile. The beneficial treatment effect of a pharmacoinvasive strategy is consistent in smokers and non-smokers.

Efficacy and safety of enoxaparin compared with unfractionated heparin in the pharmacoinvasive management of acute ST-segment elevation myocardial infarction: Insights from the TRANSFER-AMI trial

AIMS

An early invasive strategy after fibrinolysis for ST-elevation myocardial infarction (STEMI) improves outcomes, but the relative efficacy and safety of enoxaparin compared with unfractionated heparin (UFH) as part of this approach are unknown.

METHODS AND RESULTS

In the TRANSFER-AMI trial, patients with high-risk STEMI received fibrinolysis and were then randomized to either standard treatment or to immediate transfer for coronary angiography. In this substudy, the outcome of patients aged <75 years treated with enoxaparin is compared with that of patients who received UFH. Logistic regression and propensity score models were used to evaluate the efficacy and safety of these anticoagulants. Enoxaparin was administered to 498 patients, and UFH, to 448 patients, at the time of fibrinolysis. Approximately 50% in each group were randomized to the early invasive strategy. The primary composite end point of death, reinfarction, recurrent ischemia, new or worsening heart failure, or cardiogenic shock at 30 days occurred in 11.9% and 11.6% of the patients who received enoxaparin and UFH, respectively (adjusted odds ratio 0.95 [95% CI 0.60-1.51], P = .84). Enoxaparin use was associated with more access site bleeding (5.0% vs 2.9%, P = .04) and mild bleeding (12.1% vs 7.8%, P = .03).

CONCLUSIONS

Among high-risk patients with STEMI undergoing early or late transfer for cardiac catheterization after fibrinolysis, enoxaparin was associated with similar efficacy compared with UFH, but there was more minor bleeding with enoxaparin (ClinicalTrials.gov no. NCT00164190).

Prehospital evaluation and economic analysis of different coronary syndrome treatment strategies--PREDICT--rationale, development and implementation

BACKGROUND

A standard of prehospital care for patients presenting with ST-segment elevation myocardial infarction (STEMI) includes prehospital 12-lead and advance Emergency Department notification or prehospital bypass to percutaneous coronary intervention centres. Implementation of either care strategies is variable across communities and neither may exist in some communities. The main objective is to compare prehospital care strategies for time to treatment and survival outcomes as well as cost effectiveness.

METHODS/DESIGN

PREDICT is a multicentre, prospective population-based cohort study of all chest pain patients 18 years or older presenting within 30 mins to 6 hours of symptom onset and treated with nitroglycerin, transported by paramedics in a number of different urban and rural regions in Ontario. The primary objective of this study is to compare the proportion of study subjects who receive reperfusion within the target door-to-reperfusion times in subjects obtained after four prehospital strategies: 12-lead ECG and advance emergency department (ED) notification or 3-lead ECG monitoring and alert to dispatch prior to hospital arrival; either with or without the opportunity to bypass to a PCI centre.

DISCUSSION

We anticipate four challenges to successful study implementation and have developed strategies for each: 1) diversity in the interpretation of the ethical and privacy issues across 47 research ethics boards/committees covering 71 hospitals, 2) remote oversight of data guardian abstraction, 3) timeliness of implementation, and 4) potential interference in the study by concurrent technological advances. Research ethics approvals from academic centres were obtained initially and submitted to non academic centre applications. Data guardians were trained by a single investigator and data entry is informed by a detailed data dictionary including variable definitions and abstraction instructions and subjected to error and logic checks. Quality oversight provided by a single investigator. The window of the trial in each community has been confirmed with the base-hospital medical director to correspond to the planned technological advances of the system of care. We hope this comparative analysis across treatment strategies for clinical outcomes and cost will provide sufficient evidence to implement the superior strategy across all communities and improve outcomes for all STEMI patients.

Routine early angioplasty after fibrinolysis for acute myocardial infarction

BACKGROUND

Patients with a myocardial infarction with ST-segment elevation who present to hospitals that do not have the capability of performing percutaneous coronary intervention (PCI) often cannot undergo timely primary PCI and therefore receive fibrinolysis. The role and optimal timing of routine PCI after fibrinolysis have not been established.

METHODS

We randomly assigned 1059 high-risk patients who had a myocardial infarction with ST-segment elevation and who were receiving fibrinolytic therapy at centers that did not have the capability of performing PCI to either standard treatment (including rescue PCI, if required, or delayed angiography) or a strategy of immediate transfer to another hospital and PCI within 6 hours after fibrinolysis. All patients received aspirin, tenecteplase, and heparin or enoxaparin; concomitant clopidogrel was recommended. The primary end point was the composite of death, reinfarction, recurrent ischemia, new or worsening congestive heart failure, or cardiogenic shock within 30 days.

RESULTS

Cardiac catheterization was performed in 88.7% of the patients assigned to standard treatment a median of 32.5 hours after randomization and in 98.5% of the patients assigned to routine early PCI a median of 2.8 hours after randomization. At 30 days, the primary end point occurred in 11.0% of the patients who were assigned to routine early PCI and in 17.2% of the patients assigned to standard treatment (relative risk with early PCI, 0.64; 95% confidence interval, 0.47 to 0.87; P=0.004). There were no significant differences between the groups in the incidence of major bleeding.

CONCLUSIONS

Among high-risk patients who had a myocardial infarction with ST-segment elevation and who were treated with fibrinolysis, transfer for PCI within 6 hours after fibrinolysis was associated with significantly fewer ischemic complications than was standard treatment. (ClinicalTrials.gov number, NCT00164190.)

An early invasive strategy versus ischemia-guided management after fibrinolytic therapy for ST-segment elevation myocardial infarction: a meta-analysis of contemporary randomized controlled trials

BACKGROUND

Although the use of an early invasive strategy among patients with ST-segment elevation myocardial infarctions (STEMI) who are treated initially with fibrinolytic therapy is common, the safety and efficacy of this approach remains uncertain. We performed a meta-analysis to best estimate the benefits and harms of an early invasive strategy in STEMI patients treated initially with full-dose intravenous fibrinolytic therapy, as compared to a traditional strategy of ischemia-guided management.

METHODS

We included contemporary randomized controlled trials, defined a priori as those with >50% stent use during percutaneous coronary intervention (PCI). Outcomes extracted from the published results of eligible trials included all-cause mortality, reinfarction, stroke, and in-hospital major bleeding.

RESULTS

We identified 5 contemporary trials enrolling 1,235 patients who met our inclusion criteria. Of the patients randomized to an early invasive strategy, 86% underwent PCI with 87% receiving stents. Follow-up duration ranged from 30 days to 1 year. An early invasive strategy was associated with significant reductions in mortality (odds ratio [OR] 0.55, 95% CI 0.34-0.90) and reinfarction (OR 0.53, 95% CI 0.33-0.86) compared with ischemia-guided management. There were no significant differences in the risk of stroke (OR 1.31, 95% CI 0.42-4.10) or major bleeding (OR 1.41, 95% CI 0.74-2.69).

CONCLUSIONS

An early invasive strategy after fibrinolytic therapy is associated with significant reductions in mortality and reinfarction. Our results suggest a potentially important role for this strategy in the management of STEMI patients but should be confirmed by large randomized trials.

Rationale and design of the Trial of Routine ANgioplasty and Stenting After Fibrinolysis to Enhance Reperfusion in Acute Myocardial Infarction (TRANSFER-AMI)

BACKGROUND

Most patients with ST-elevation myocardial infarction present to hospitals without percutaneous coronary intervention (PCI) facilities and receive fibrinolysis. The role of routine early PCI after fibrinolysis, using stents and contemporary pharmacotherapy, has not been studied in a large adequately powered randomized trial.

OBJECTIVE

To compare a pharmacoinvasive strategy of transfer for routine PCI within 6 hours after fibrinolysis with standard treatment after fibrinolysis (including predefined criteria for rescue PCI and delayed cardiac catheterization for patients who do not require rescue PCI).

METHODS

A total of 1200 patients with high-risk ST-elevation myocardial infarction presenting to non-PCI centers will be randomized to a pharmacoinvasive strategy (transfer for routine PCI within 6 hours of fibrinolysis) or to standard treatment after fibrinolysis. The primary end point is the 30-day composite of death, reinfarction, recurrent ischemia, heart failure, or shock.

RESULTS

More than 900 patients have been enrolled as of April 2007. An interim safety analysis of the first 536 patients demonstrated no safety concerns. Enrolment is expected to be completed in late 2007.

CONCLUSIONS

This study will provide important data on whether routine early PCI within 6 hours after fibrinolysis is safe and superior to the standard treatment of fibrinolysis with rescue PCI or delayed cardiac catheterization.