One year results of the Middlesbrough early revascularisation to limit infarction (MERLIN) trial

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.

Safety and efficacy of rescue angioplasty for ST-elevation myocardial infarction with high utilization rates of glycoprotein IIb/IIIa inhibitors

BACKGROUND

Fibrinolytic therapies remain widely used for ST-elevation myocardial infarction, and for "failed reperfusion," rescue percutaneous coronary intervention (PCI) is guideline recommended to improve outcomes. However, these recommendations are based on data from an earlier era of pharmacotherapy and procedural techniques.

METHODS AND RESULTS

To determine factors affecting prognosis after rescue PCI, we studied 241 consecutive patients (median age 55 years, interquartile range [IQR] 48-65) undergoing procedures between 2001 and 2009 (53% anterior ST-elevation myocardial infarction and 78% transferred). The median treatment-related times were 1.2 hours (IQR 0.8-2.2) from symptom onset to door, 2 hours (IQR 1.3-3.2) from symptom onset to fibrinolysis (93% tenecteplase), and 3.9 hours (IQR 3.1-5.2) from fibrinolysis to balloon. Procedural characteristics were stent deployment in 95% (11.6% drug eluting) and 78% glycoprotein IIb/IIIa inhibitor use, and Thrombolysis In Myocardial Infarction (TIMI) 3 flow rates pre-PCI and post-PCI were 41% and 91%, respectively (P < .001). At 30 days, TIMI major bleeding occurred in 16 (6.6%) patients, and 23 (9.5%) patients received transfusions; nonfatal stroke occurred in 4 (1.7%) patients (2 hemorrhagic). Predictors of TIMI major bleeding were female gender (odds ratio 3.194, 95% CI 1.063-9.597; P = .039) and pre-PCI shock (odds ratio 3.619, 95% CI,1.073-12.207; P = .038). Mortality at 30 days was 6.2%, and 3.2% in patients without pre-PCI shock. One-year mortality was 8.2% (5.3% in patients without pre-PCI cardiogenic shock), 5.2% had reinfarction, and the target vessel revascularization rate was 6.4% (2.6% in arteries ≥ 3.5 mm in diameter). Pre-PCI shock, female gender, and post-PCI TIMI flow grades ≤ 2 were significant predictors of 1-year mortality on multivariable regression modeling, but TIMI major bleeding was not.

CONCLUSIONS

Rescue PCI with contemporary treatments can achieve mortality rates similar to rates for contemporary primary PCI in patients without pre-PCI shock. Whether rates of bleeding can be reduced by different pharmacotherapies and interventional techniques needs clarification in future studies.

Routine invasive management after fibrinolysis in patients with ST-elevation myocardial infarction: a systematic review of randomized clinical trials

Background

Patients with ST-elevation myocardial infarction (STEMI) treated with fibrinolysis are increasingly, and ever earlier, referred for routine coronary angiography and where feasible, undergo percutaneous coronary intervention (PCI). We sought to examine the randomized clinical trials (RCTs) on which this approach is based.

Methods

We systematically searched EMBASE, Medline, and references of relevant studies. All contemporary RCTs (published since 1995) that compared systematic invasive management of STEMI patients after fibrinolysis with standard care were included. Relevant study design and clinical outcome data were extracted.

Results

Nine RCTs that randomized a total of 3320 patients were identified. All suggested a benefit from routine early invasive management. They were individually reviewed but important design variations precluded a formal quantitative meta-analysis. Importantly, several trials did not compare a routine practice of invasive management after fibrinolysis with a more selective 'ischemia-guided' approach but rather compared an early versus later routine invasive strategy. In the other studies, recourse to subsequent invasive management in the usual care group varied widely. Comparison of the effectiveness of a routine invasive approach to usual care was also limited by asymmetric use of a second anti-platelet agent, differing enzyme definitions of reinfarction occurring spontaneously versus as a complication of PCI, a preponderance of the 'soft' outcome of recurrent ischemia in the combined primary endpoint, and an interpretative bias when invasive procedures on follow-up were tallied as an endpoint without considering initial invasive procedures performed in the routine invasive arm.

Conclusions

Due to important methodological limitations, definitive RCT evidence in favor of routine invasive management following fibrinolysis in patients with STEMI is presently lacking.

Comparison of one-year cardiac events with drug-eluting versus bare metal stent implantation in rescue coronary angioplasty

Rescue percutaneous coronary intervention (PCI) with bare metal stent (BMS) implantation is useful in patients with acute myocardial infarction (AMI) and failed thrombolysis. Drug-eluting stent (DESs) are more effective in reducing restenosis compared to BMS. No data are available comparing the clinical outcomes between the 2 types of stents nor has information ever been provided about the predictors of events in patients treated with rescue PCI in the current era. The aims of the present study were to evaluate the outcomes of patients undergoing rescue PCI with DES implantation compared to BMS implantation and to determine the independent predictors of events during 1 year of follow-up. The study population consisted of 311 consecutive patients with ST-segment elevation AMI and evidence of failed fibrinolysis undergoing successful revascularization with DES (n = 134) or BMS (n = 177) implantation. The end point of the present study was the incidence of major adverse cardiac events (MACE) defined as death, recurrent AMI, and target vessel revascularization. No differences were found in the number of MACE at 1 year of follow-up between the DES and BMS groups (n = 10 and 19, respectively, p = 0.29). The Cox proportional hazards model identified cardiogenic shock (adjusted hazard ratio 7.05, 95% confidence interval 2.08 to 23.9, p = 0.001), age (hazard ratio 1.51, 95% CI 1.09 to 2.08, p = 0.011), and final minimal lumen diameter (hazard ratio 0.42, 95% confidence interval 0.21 to 0.83, p = 0.013) as independent predictors of MACE at 1 year of follow-up. After propensity score adjustments, the predictors did not change. In conclusion, we found no differences between DESs and BMSs with respect to MACE at 1 year of follow-up in patients with AMI treated with rescue PCI. Cardiogenic shock, age, and final minimal luminal diameter were identified as predictors of MACE.

Early routine percutaneous coronary intervention after fibrinolysis vs. standard therapy in ST-segment elevation myocardial infarction: a meta-analysis

AIMS

Multiple trials in patients with ST-segment elevation myocardial infarction (STEMI) compared early routine percutaneous coronary intervention (PCI) after successful fibrinolysis vs. standard therapy limiting PCI only to patients without evidence of reperfusion (rescue PCI). These trials suggest that all patients receiving fibrinolysis should receive mechanical revascularization within 24 h from initial hospitalization. However, individual trials could not demonstrate a significant reduction in 'hard' endpoints such as death and reinfarction. We performed a meta-analysis of randomized controlled trials to define the benefits of early PCI after fibrinolysis over standard therapy on clinical and safety endpoints in STEMI.

METHODS AND RESULTS

We identified seven eligible trials, enrolling a total of 2961 patients. No difference was found in the incidence of death at 30 days between the two strategies. Early PCI after successful fibrinolysis reduced the rate of reinfarction (OR: 0.55, 95% CI: 0.36-0.82; P = 0.003), the combined endpoint death/reinfarction (OR: 0.65, 95% CI: 0.49-0.88; P = 0.004) and recurrent ischaemia (OR: 0.25, 95% CI: 0.13-0.49; P < 0.001) at 30-day follow-up. These advantages were achieved without a significant increase in major bleeding (OR: 0.93, 96% CI: 0.67-1.34; P = 0.70) or stroke (OR: 0.63, 95% CI: 0.31-1.26; P = 0.21). The benefits of a routine invasive strategy over standard therapy were maintained at 6-12 months, with persistent significant reduction in the endpoints reinfarction (OR: 0.64, 95% CI: 0.40-0.98; P = 0.01) and combined death/reinfarction (OR: 0.71, 95% CI: 0.52-0.97; P = 0.03).

CONCLUSION

Early routine PCI after fibrinolysis in STEMI patients significantly reduced reinfarction and recurrent ischaemia at 1 month, with no significant increase in adverse bleeding events compared to standard therapy. Benefits of early PCI persist at 6-12 month follow-up.

Percutaneous coronary intervention following thrombolysis: for whom and when?

Primary percutaneous coronary intervention (PPCI) is the treatment of choice for patients with ST segment elevation myocardial infarction (STEMI). In the attempt to reduce the unfavourable effects of time delays before PPCI, the administration of thrombolysis has been advocated (facilitated-PCI), but this treatment was shown to be ineffective and harmful, and should be avoided in patients who can receive PPCI promptly. Fibrinolysis is still indicated when PPCI is not available within 90-120 min but 1/3 of STEMI patients undergoing fibrinolysis does not show signs of reperfusion and even when reperfusion is achieved they have a considerable risk of death and recurrent MI. Thus invasive management with early PCI could be complementary to fibrinolysis both to obtain coronary reperfusion in those patients with failed thrombolysis (rescue-PCI) and to decrease the risk of further ischaemic events in patients with successful thrombolysis. In this article we show that this synergy has been supported by modern randomized control trials and meta-analysis. It is advisable that organization model of territorial network for the treatment of STEMI patients should be expanded to provide a timely access to hospital with interventional facilities also to patients treated with fibrinolysis that need rescue-PPCI or an urgent/early invasive management.

Rescue angioplasty for failed thrombolysis in older patients: Insights from the REACT trial

BACKGROUND

Thrombolysis remains the first-line therapy in a substantial proportion of patients presenting with ST elevation myocardial infarction. The optimal treatment for patients in whom there is failure of reperfusion following thrombolysis is unclear. The Rescue Angioplasty versus Conservative Treatment or Repeat Thrombolysis (REACT) trial demonstrated, in 427 randomly assigned patients with failed reperfusion following thrombolysis, that event-free survival rates were significantly improved with rescue angioplasty compared with either repeat thrombolysis or conservative treatment. However, the safety and efficacy of rescue angioplasty among older patients remains uncertain.

METHODS AND RESULTS

We aimed to determine whether rescue angioplasty was safe and effective in an older population, by evaluating the primary and secondary clinical outcomes among the 105 patients >or=70 years of age in the REACT trial. We observed an increased overall 6-month event rate among older patients. The relative benefit of rescue angioplasty versus repeat thrombolysis or conservative treatment was maintained, and the absolute benefit actually increased in this older age group compared with the study population as a whole. There was no adverse impact of advanced age on bleeding complications. Repeat thrombolysis was no more effective than conservative therapy.

CONCLUSIONS

Rescue angioplasty is the preferred management strategy for failed thrombolysis, even for patients >or=70 years of age.

Early invasive versus conservative treatment in patients with failed fibrinolysis--no late survival benefit: the final analysis of the Middlesbrough Early Revascularisation to Limit Infarction (MERLIN) randomized trial

BACKGROUND

Early (30 days) and midterm (6 months) clinical outcomes in trials comparing rescue angioplasty (rescue percutaneous coronary intervention [rPCI]) with conservative treatment of failed fibrinolysis complicating ST-segment elevation myocardial infarction have shown variable results. Whether early rPCI confers late (up to 3 years) clinical benefits is not known.

METHODS

The MERLIN trial compared rPCI and a conservative strategy in patients with failed fibrinolysis complicating ST-segment elevation myocardial infarction. Three hundred seven patients with electrocardiographic evidence of failure to reperfuse at 60 minutes were included. Patients in cardiogenic shock were excluded. Thirty-day and 1-year results have been reported. Results of 3 years of follow-up are presented.

RESULTS

Three-year mortality in the conservative arm and rPCI, respectively, was 16.9% versus 17.6% (P = .9, relative difference [RD] -0.8, 95% CI [-9.3 to 7.8]). Death rates were similar (3.9% vs 3.2%) between 1- and 3-year follow-up, respectively. The incidence of the composite secondary end point of death, reinfarction, stroke, unplanned revascularization, or heart failure was significantly higher in the conservative arm (64.3% vs 49%, P = .01, RD 15.3, 95% CI [4.2-26]). There was no significant difference in the rate of reinfarction (0.7% vs 0.7%) or heart failure (1.3% vs 2.7%) between 1 and 3 years between the conservative and rPCI arms, respectively. The incidence of subsequent unplanned revascularization at 3 years was significantly higher in the conservative arm (33.8% vs 14.4%, P < .01, RD 19.4, 95% CI [10-28.7]), most of which occurred within 1 year; the rates between 1 and 3 years were 3.9% in the conservative arm versus 2% in the rPCI arm. There was a trend toward fewer strokes in the conservative arm at 3 years (conservative arm 2.6% vs rPCI 6.5%, P = .1, RD -3.9%, 95% CI [-9.4 to 0.8]), with similar stroke rates (1.3% vs 1.3%) between 1- and 3-year follow-up.

CONCLUSIONS

Rescue angioplasty did not confer a late survival advantage at 3 years. The composite end point occurred less often in the rPCI arm mainly because of fewer unplanned revascularization procedures in the early phase of follow-up. The highest risk of clinical events in patients with failed reperfusion is in the first year, beyond which the rate of clinical events is low.

Management of failed thrombolysis after acute myocardial infarction: An overview of current treatment options

Thrombolytic therapy remains the most commonly administered revascularization strategy for patients with ST-elevation myocardial infarctions (STEMI). However, many patients fail to have patent arteries or ST-segment resolution after these therapies. Multiple strategies have been examined to treat these patients with "failed thrombolysis." We examined the existing medical literature regarding treatment of failed thrombolysis including strategies testing repeat thrombolytic therapy and rescue percutaneous coronary intervention. Additional, we reviewed the literature regarding the efficacy of transferring patient for rescue percutaneous intervention and coronary stenting. The impact of contemporary antiplatelet strategies, cardiogenic shock, and coronary bypass surgery was examined. Overall, the management of patients with acute STEMI in whom thrombolytic therapy failed remains a challenging problem. As a result, many different strategies are currently in use. Among these therapeutic interventions, rescue PCI with coronary stenting appears to be superior when it is done in a timely manner by an experienced center.

Acute ischemic heart disease and interventional cardiology: a time for pause

BACKGROUND

A major change has occurred in the last few years in the therapeutic approach to patients presenting with all forms of acute coronary syndromes. Whether or not these patients present initially to tertiary cardiac care centers, they are now routinely referred for early coronary angiography and increasingly undergo percutaneous revascularization. This practice is driven primarily by the angiographic image and technical feasibility. Concomitantly, there has been a decline in expectant or ischemia-guided medical management based on specific clinical presentation, response to initial treatment, and results of noninvasive stratification. This 'tertiarization' of acute coronary care has been fueled by the increasing sophistication of the cardiac armamentarium, the peer-reviewed publication of clinical studies purporting to show the superiority of invasive cardiac interventions, and predominantly supporting (non-peer-reviewed) editorials, newsletters, and opinion pieces.

DISCUSSION

This review presents another perspective, based on a critical reexamination of the evidence. The topics addressed are: reperfusion treatment of ST-elevation myocardial infarction; the indications for invasive intervention following thrombolysis; the role of invasive management in non-ST-elevation myocardial infarction and unstable angina; and cost-effectiveness and real world considerations. A few cases encountered in recent practice in community and tertiary hospitals are presented for illustrative purposes The numerous and far-reaching scientific, economic, and philosophical implications that are a consequence of this marked change in clinical practice as well as healthcare, decisional and conflict of interest issues are explored.

SUMMARY

The weight of evidence does not support the contemporary unfocused broad use of invasive interventional procedures across the spectrum of acute coronary clinical presentations. Excessive and unselective recourse to these procedures has deleterious implications for the organization of cardiac health care and undesirable economic, scientific and intellectual consequences. It is suggested that there is need for a new equilibrium based on more refined clinical risk stratification in the treatment of patients who present with acute coronary syndromes.

Percutaneous Coronary Intervention After Fibrinolysis

OBJECTIVES

We performed a meta-analysis of randomized trials that enrolled ST-segment elevation myocardial infarction patients treated with fibrinolysis to assess the potential benefits of: 1) rescue percutaneous coronary intervention (PCI) versus no PCI; 2) systematic and early (< or =24 h) PCI versus delayed or ischemia-guided PCI; 3) fibrinolysis-facilitated PCI versus primary PCI alone.

BACKGROUND

The impact of PCI strategies after fibrinolysis on mortality or reinfarction remains to be established.

METHODS

The meta-analysis was performed using the odds ratio (OR) as the parameter of efficacy with a random effect model. Fifteen randomized trials (5,253 patients) were selected. The primary end point was mortality or the combined end point of death or reinfarction.

RESULTS

Rescue PCI for failed fibrinolysis reduced mortality (6.9% vs. 10.7%) (OR, 0.63; 95% confidence interval [CI], 0.39 to 0.99; p = 0.055) and the rate of death or reinfarction (10.8% vs. 16.8%) (OR, 0.60; 95% CI, 0.41 to 0.89; p = 0.012) compared with a conservative approach. Systematic and early PCI performed during the "stent era" led to a nonsignificant reduction in mortality compared with delayed or ischemia-guided PCI (3.8% vs. 6.7%) (OR, 0.56; 95% CI, 0.29 to 1.05; p = 0.07) and to a 2-fold reduction in the rate of death or reinfarction (7.5% vs. 13.2%) (OR, 0.53; 95% CI, 0.33 to 0.83; p = 0.0067). This benefit contrasted with a nonsignificant increase in the rate of both mortality (5.5% vs. 3.9%, p = 0.33) or death or reinfarction (9.6% vs. 5.7%, p = 0.06) observed in the "balloon era." Fibrinolysis-facilitated PCI was associated with more reinfarction as compared with primary PCI alone (5.0% vs. 3.0%) (OR, 1.68; 95% CI, 1.12 to 2.51; p = 0.013) without significant impact on mortality (OR, 1.30; 95% CI, 0.92 to 1.83; p = 0.13).

CONCLUSIONS

Our findings support rescue PCI and systematic and early PCI after fibrinolysis. However, the current data do not support fibrinolysis-facilitated PCI in lieu of primary PCI alone.