Impact of invasive management versus noninvasive management on functional status and quality of life following non-Q-wave myocardial infarction: a randomized clinical trial

Non-ST-elevation acute coronary syndromes with previous coronary artery bypass grafting: a meta-analysis of invasive vs. conservative management

BACKGROUND AND AIMS

A routine invasive strategy is recommended in the management of higher risk patients with non-ST-elevation acute coronary syndromes (NSTE-ACSs). However, patients with previous coronary artery bypass graft (CABG) surgery were excluded from key trials that informed these guidelines. Thus, the benefit of a routine invasive strategy is less certain in this specific subgroup.

METHODS

A systematic review and meta-analysis of randomized controlled trials (RCTs) was conducted. A comprehensive search was performed of PubMed, EMBASE, Cochrane, and ClinicalTrials.gov. Eligible studies were RCTs of routine invasive vs. a conservative or selective invasive strategy in patients presenting with NSTE-ACS that included patients with previous CABG. Summary data were collected from the authors of each trial if not previously published. Outcomes assessed were all-cause mortality, cardiac mortality, myocardial infarction, and cardiac-related hospitalization. Using a random-effects model, risk ratios (RRs) with 95% confidence intervals (CIs) were calculated.

RESULTS

Summary data were obtained from 11 RCTs, including previously unpublished subgroup outcomes of nine trials, comprising 897 patients with previous CABG (477 routine invasive, 420 conservative/selective invasive) followed up for a weighted mean of 2.0 (range 0.5-10) years. A routine invasive strategy did not reduce all-cause mortality (RR 1.12, 95% CI 0.97-1.29), cardiac mortality (RR 1.05, 95% CI 0.70-1.58), myocardial infarction (RR 0.90, 95% CI 0.65-1.23), or cardiac-related hospitalization (RR 1.05, 95% CI 0.78-1.40).

CONCLUSIONS

This is the first meta-analysis assessing the effect of a routine invasive strategy in patients with prior CABG who present with NSTE-ACS. The results confirm the under-representation of this patient group in RCTs of invasive management in NSTE-ACS and suggest that there is no benefit to a routine invasive strategy compared to a conservative approach with regard to major adverse cardiac events. These findings should be validated in an adequately powered RCT.

Meta-Analysis of Randomized Trials of Long-Term All-Cause Mortality in Patients With Non-ST-Elevation Acute Coronary Syndrome Managed With Routine Invasive Versus Selective Invasive Strategies

Randomized trials and meta-analyses demonstrated that a routine invasive strategy improves outcomes in patients with non-ST-elevation acute coronary syndrome (NSTE-ACS) compared to a selective invasive strategy. Benefit was driven primarily by a reduction in the risk of myocardial infarction. However, the impact of either strategy on long-term mortality is unknown. Trials that compared a routine invasive strategy versus a selective invasive strategy in patients with NSTE-ACS and reported data on all-cause mortality ≥1 year were included. Summary odds ratios (OR) were constructed using Peto's model for all-cause mortality using the longest available follow-up data. Subgroup analysis was performed for follow-up at 1 to ≤5 years and >5 years. Eight trials with 6,657 patients were available for analysis. At a mean of 10.3 years, the risk of all-cause mortality was similar with both strategies (28.5% vs 28.5%; OR 1.00, 95% confidence interval [CI] 0.90 to 1.12, p = 0.97). This effect was similar on subgroup analysis for follow-up at 1 to ≤5 years (OR 0.89, 95% CI 0.77 to 1.04, p = 0.15) and >5 years (OR 1.02, 95% CI 0.90 to 1.14, p = 0.79). There was no difference in treatment effect across various study-level covariates such as age, gender, diabetes, and positive troponin (all P for interaction >0.05). In conclusion, in patients with NSTE-ACS, both routine invasive and selective invasive strategies have a similar risk of all-cause mortality at ∼10 years. This illustrates there are still opportunities to change the trajectory of mortality events among invasively treated patients with NSTE-ACS.

Early Invasive Strategy for Unstable Angina: a New Meta-Analysis of Old Clinical Trials

Randomized controlled trials (RCTs) were conflicting to support whether unstable angina versus non-ST-elevation myocardial infarction (UA/NSTEMI) patients best undergo early invasive or a conservative revascularization strategy. RCTs with cardiac biomarkers, in MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials from 1975-2013 were reviewed considering all cause mortality, recurrent non-fatal myocardial infarction (MI) and their combination. Follow-up lasted from 6-24 months and the use of routine invasive strategy up to its end was associated with a significantly lower composite of all-cause mortality and recurrent non-fatal MI (Relative Risk [RR] 0.79; 95% confidence interval [CI], 0.70-0.90) in UA/NSTEMI. In NSTEMI, by the invasive strategy, there was no benefit (RR 1.19; 95% CI, 1.03-1.38). In the shorter time period, from randomization to discharge, a routine invasive strategy was associated with significantly higher odds of the combined end-point among UA/NSTEMI (RR 1.29; 95% CI, 1.05-1.58) and NSTEMI (RR 1.82; 95% CI, 1.34-2.48) patients. Therefore, in trials recruiting a large number of UA patients, by routine invasive strategy the largest benefit was seen, whereas in NSTEMI patients death and non-fatal MI were not lowered. Routine invasive treatment in UA patients is accordingly supported by the present study.

Routine invasive strategies versus selective invasive strategies for unstable angina and non-ST elevation myocardial infarction in the stent era

BACKGROUND

People with unstable angina and non-ST elevation myocardial infarction (UA/NSTEMI) are managed with a combination of medical therapy, invasive angiography and revascularisation. Specifically, two approaches have evolved: either a 'routine invasive' strategy whereby all patients undergo coronary angiography shortly after admission and, if indicated, coronary revascularisation; or a 'selective invasive' (also referred to as 'conservative') strategy in which medical therapy alone is used initially, with a selection of patients for angiography based upon evidence of persistent myocardial ischaemia. Uncertainty exists as to which strategy provides the best outcomes for these patients. This Cochrane review is an update of a Cochrane review originally published in 2006, to provide a robust comparison of these two strategies in the early management of patients with UA/NSTEMI.

OBJECTIVES

To determine the benefits and harms associated with the following.1. A routine invasive versus a conservative or 'selective invasive' strategy for the management of UA/NSTEMI in the stent era.2. A routine invasive strategy with and without glycoprotein IIb/IIIa receptor antagonists versus a conservative strategy for the management of UA/NSTEMI in the stent era.

SEARCH METHODS

We searched the following databases and additional resources up to 25 August 2015: the Cochrane Central Register of Controlled Trials (CENTRAL) on the Cochrane Library, MEDLINE and EMBASE, with no language restrictions.

SELECTION CRITERIA

We included prospective randomised controlled trials (RCTs) that compared invasive with conservative or 'selective invasive' strategies in participants with acute UA/NSTEMI.

DATA COLLECTION AND ANALYSIS

Two review authors screened the records and extracted data in duplicate. Using intention-to-treat analysis with random-effects models, we calculated summary estimates of the risk ratio (RR) with 95% confidence intervals (CIs) for the primary endpoints of all-cause death, fatal and non-fatal myocardial infarction (MI), combined all-cause death or non-fatal MI, refractory angina and re-hospitalisation. We performed further analysis of included studies based on whether glycoprotein IIb/IIIa receptor antagonists were used routinely. We assessed the heterogeneity of included trials using Pearson χ² (Chi² test) and variance (I² statistic) analysis. Using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach, we assessed the quality of the evidence and the GRADE profiler (GRADEPRO) was used to import data from Review Manager 5.3 (Review Manager) to create Summary of findings (SoF) tables.

MAIN RESULTS

Eight RCTs with a total of 8915 participants (4545 invasive strategies, 4370 conservative strategies) were eligible for inclusion. We included three new studies and 1099 additional participants in this review update. In the all-study analysis, evidence did not show appreciable risk reductions in all-cause mortality (RR 0.87, 95% CI 0.64 to 1.18; eight studies, 8915 participants; low quality evidence) and death or non-fatal MI (RR 0.93, 95% CI 0.71 to 1.2; seven studies, 7715 participants; low quality evidence) with invasive strategies compared to conservative (selective invasive) strategies at six to 12 months follow-up. There was appreciable risk reduction in MI (RR 0.79, 95% CI 0.63 to 1.00; eight studies, 8915 participants; moderate quality evidence), refractory angina (RR 0.64, 95% CI 0.52 to 0.79; five studies, 8287 participants; moderate quality evidence) and re-hospitalisation (RR 0.77, 95% CI 0.63 to 0.94; six studies, 6921 participants; moderate quality evidence) with routine invasive strategies compared to conservative (selective invasive) strategies also at six to 12 months follow-up.Evidence also showed increased risks in bleeding (RR 1.73, 95% CI 1.30 to 2.31; six studies, 7584 participants; moderate quality evidence) and procedure-related MI (RR 1.87, 95% CI 1.47 to 2.37; five studies, 6380 participants; moderate quality evidence) with routine invasive strategies compared to conservative (selective invasive) strategies.The low quality evidence were as a result of serious risk of bias and imprecision in the estimate of effect while moderate quality evidence was only due to serious risk of bias.

AUTHORS' CONCLUSIONS

In the all-study analysis, the evidence failed to show appreciable benefit with routine invasive strategies for unstable angina and non-ST elevation MI compared to conservative strategies in all-cause mortality and death or non-fatal MI at six to 12 months. There was evidence of risk reduction in MI, refractory angina and re-hospitalisation with routine invasive strategies compared to conservative (selective invasive) strategies at six to 12 months follow-up. However, routine invasive strategies were associated with a relatively high risk (almost double the risk) of procedure-related MI, and increased risk of bleeding complications. This systematic analysis of published RCTs supports the conclusion that, in patients with UA/NSTEMI, a selectively invasive (conservative) strategy based on clinical risk for recurrent events is the preferred management strategy.

Depression and self-reported functional status: impact on mortality following acute myocardial infarction

OBJECTIVE

The cause of increased post-AMI (acute myocardial infarction) mortality associated with depression remains poorly elucidated. The objective of this study was to examine the extent to which self-reported cardiac functional status accounted for depression-mortality associations following AMI.

METHODS

Using a prospective cohort design (n = 1941), the authors obtained self-reported measures of depression and developed profiles of the patients' pre-hospitalization cardiac risks, co-morbid conditions and drugs and revascularization procedures during or following index AMI hospitalization. To create these profiles, the patients' self-reports were retrospectively linked to no less than 12 years' worth of previous hospitalization data. Mortality rates 2 years after acute MI were examined with and without sequential risk adjustment for age, sex, income, cardiovascular risk, co-morbid conditions, selected process-of-care factors and self-reported cardiac functional status.

RESULTS

Depression was strongly correlated with 2-year mortality rate [crude hazard ratio (HR) of severe vs. minimal depression category, 2.48 (95% CI 1.20-5.15); P = 0.01]. However, after sequential adjustment for age, sex, income and self-reported cardiac functional status, the effect of depression was greatly attenuated [adjusted HR for severe vs. minimal depression category, 1.35 (95% CI 0.63-2.87); P = 0.44]. Cardiac risk factors and non-cardiac co-morbidities had negligible explanatory effect.

DISCUSSION

The main factor determining the increased mortality rate in depressed patients is self-reported cardiac functional status. Efforts to address increased mortality in depressed patients with cardiovascular illnesses should focus on processes that impact cardiac functional status.

Early invasive versus conservative strategies for unstable angina and non-ST elevation myocardial infarction in the stent era

BACKGROUND

In patients with unstable angina and non-ST elevation myocardial infarction (UA/NSTEMI) two strategies are possible, either a routine invasive strategy where all patients undergo coronary angiography shortly after admission and, if indicated, coronary revascularization; or a conservative strategy where medical therapy alone is used initially, with selection of patients for angiography based on clinical symptoms or investigational evidence of persistent myocardial ischemia.

OBJECTIVES

To determine the benefits of an invasive compared to conservative strategy for treating UA/NSTEMI in the stent era.

SEARCH STRATEGY

The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2008, Issue 1), MEDLINE and EMBASE were searched (1996 to February 2008) with no language restrictions.

SELECTION CRITERIA

Included studies were prospective trials comparing invasive with conservative strategies in UA/NSTEMI.

DATA COLLECTION AND ANALYSIS

We identified five studies (7818 participants). Using intention-to-treat analysis with random-effects models, summary estimates of relative risk (RR) with 95% confidence interval (CI) were determined for primary end-points of all-cause death, fatal and non-fatal myocardial infarction, all-cause death or non-fatal myocardial infarction, and refractory angina. Further analysis of included studies was undertaken based on whether glycoprotein IIb/IIIa receptor antagonists were used routinely. Heterogeneity was assessed using Chi(2) and variance (I(2) statistic) methods.

MAIN RESULTS

In the all-study analysis, mortality during initial hospitalization showed a trend to hazard with an invasive strategy (RR 1.59, 95% CI 0.96 to 2.64). The invasive strategy did not reduce death on longer-term follow up. Myocardial infarction rates assessed at 6 to 12 months (5 trials) and 3 to 5 years (3 trials) were significantly decreased by an invasive strategy (RR 0.73, 95% CI 0.62 to 0.86; and RR 0.78, 95% CI 0.67 to 0.92 respectively). The incidence of early (< 4 month) and intermediate (6 to 12 month) refractory angina were both significantly decreased by an invasive strategy (RR 0.47, 95% CI 0.32 to 0.68; and RR 0.67, 95% CI 0.55 to 0.83 respectively), as were early and intermediate rehospitalization rates (RR 0.60, 95% CI 0.41to 0.88; and RR 0.67, 95% CI 0.61 to 0.74 respectively). The invasive strategy was associated with a two-fold increase in the RR of peri-procedural myocardial infarction (as variably defined) and a 1.7-fold increase in the RR of (minor) bleeding with no hazard of stroke.

AUTHORS' CONCLUSIONS

Compared to a conservative strategy for UA/NSTEMI, an invasive strategy is associated with reduced rates of refractory angina and rehospitalization in the shorter term and myocardial infarction in the longer term. However, the invasive strategy is associated with a doubled risk of procedure-related heart attack and increased risk of bleeding and procedural biomarker leaks. Available data suggest that an invasive strategy may be particularly useful in those at high risk for recurrent events.