Invasive Versus Medical Management in Patients With Prior Coronary Artery Bypass Surgery With a Non-ST Segment Elevation Acute Coronary Syndrome

Frailty in acute coronary syndromes. A systematic review and narrative synthesis of frailty assessment tools and interventions from randomised controlled trials

AIM

We aimed to review all randomised controlled trial (RCT) data to explore optimal identification and treatment strategies of frail patients with Acute Coronary Syndromes (ACS).

METHODS

The protocol was preregistered (PROSPERO - CRD42021250235). We performed a systematic review including RCT's that 1; used at least one frailty assessment tool to assess frailty and its impact on outcomes in patients diagnosed with ACS and 2; used at least one intervention where change in frailty was measured in patients diagnosed with ACS. The Cochrane Central Register of Controlled Trials, MEDLINE and EMBASE were searched on the 1st April 2021 and updated on 4th July 2023. Owing to low search output results are presented as a narrative synthesis of available evidence.

RESULTS

A single RCT used a frailty assessment tool. A single RCT specifically targeted frailty with their intervention. This precluded further quantitative analysis. There was indication of selection bias against frail participants, and a signal of value for physical activity measurement in frail ACS patients. There was a high level of uncertainty and low level of robustness of this evidence.

CONCLUSIONS

Data from RCT's alone is inadequate in answering the reviews question. Future RCT's need to address ways to incorporate frail participants, whilst mitigating selection biases. Physical performance aspects of the frailty syndrome appear to be high yield modifiable targets that improve outcomes. Intervention trials should consider using change in frailty status as an outcome measure. Any trials that include frail participants should present data specifically attributable to this group.

Comprehensive evaluation of time-varied outcomes for invasive and conservative strategies in patients with NSTE-ACS: a meta-analysis of randomized controlled trials

Background

Results from randomized controlled trials (RCTs) and meta-analyses comparing invasive and conservative strategies in patients with non-ST-elevation acute coronary syndrome (NSTE-ACS) are highly debatable. We systematically evaluate the efficacy of invasive and conservative strategies in NSTE-ACS based on time-varied outcomes.

Methods

The RCTs for the invasive versus conservative strategies were identified by searching PubMed, Cochrane Central Register of Controlled Trials, Embase, and ClinicalTrials.gov. Trial data for studies with a minimum follow-up time of 30 days were included. We categorized the follow-up time into six varied periods, namely, ≤6 months, 1 year, 2 years, 3 years, 5 years, and ≥10 years. The time-varied outcomes were major adverse cardiovascular event (MACE), death, myocardial infarction (MI), rehospitalization, cardiovascular death, bleeding, in-hospital death, and in-hospital bleeding. Risk ratios (RRs) and 95% confidence intervals (Cis) were calculated. The random effects model was used.

Results

This meta-analysis included 30 articles of 17 RCTs involving 12,331 participants. We found that the invasive strategy did not provide appreciable benefits for NSTE-ACS in terms of MACE, death, and cardiovascular death at all time points compared with the conservative strategy. Although the risk of MI was reduced within 6 months (RR 0.80, 95% CI 0.68-0.94) for the invasive strategy, no significant differences were observed in other periods. The invasive strategy reduced the rehospitalization rate within 6 months (RR 0.69, 95% CI 0.52-0.90), 1 year (RR 0.73, 95% CI 0.63-0.86), and 2 years (RR 0.77, 95% CI 0.60-1.00). Of note, an increased risk of bleeding (RR 1.80, 95% CI 1.28-2.54) and in-hospital bleeding (RR 2.17, 95% CI 1.52-3.10) was observed for the invasive strategy within 6 months. In subgroups stratified by high-risk features, the invasive strategy decreased MACE for patients aged ≥65 years within 6 months (RR 0.68, 95% CI 0.58-0.78) and 1 year (RR 0.75, 95% CI 0.62-0.91) and showed benefits for men within 6 months (RR 0.71, 95% CI 0.55-0.92). In other subgroups stratified according to diabetes, ST-segment deviation, and troponin levels, no significant differences were observed between the two strategies.

Conclusions

An invasive strategy is superior to a conservative strategy in reducing early events for MI and rehospitalizations, but the invasive strategy did not improve the prognosis in long-term outcomes for patients with NSTE-ACS.

Systematic Review Registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021289579, identifier PROSPERO 2021 CRD42021289579.

In-hospital Outcomes of Patients With and Without Previous Coronary Artery Bypass Graft Surgery Who Present With a Non-ST-Segment Elevation Myocardial Infarction

The clinical course of patients with a previous coronary artery bypass graft surgery (CABG) presenting with non-ST-elevation myocardial infarction (NSTEMI) is not well defined. We aimed to compare the management and outcomes of patients with and without previous CABG who present with an NSTEMI. Patients hospitalized with an NSTEMI between 2002 and 2018 were identified from the National Inpatient Sample. The baseline characteristics and outcomes of patients with and without a previous CABG were compared. The outcomes included the rates of invasive procedures (defined as coronary angiography, percutaneous coronary intervention [PCI], or CABG), and its individual components, and in-hospital mortality. A total of 1,445,545 cases of NSTEMI were found, of which 133,691 (9.3%) had a previous CABG. Patients with a previous CABG were older (72.4 vs 68.6 years, p <0.001), more likely men (68.8% vs 56.9%, p <0.001), and of White race (79.7% vs 74.8%, p <0.001). The previous CABG cohort had lower rates of invasive procedures (50.4% vs 65.6%, p <0.001), PCI (23.7% vs 32.0%, p <0.001), or CABG (1.2% vs 10.6%; p <0.001) in the unmatched analysis. The results were consistent in the propensity score-matched analysis with the previous CABG group less likely to receive any invasive procedures (odds ratio [OR] 0.48, 95% confidence interval [CI] 0.47 to 0.49), including coronary angiography (OR 0.54, 95% CI 0.53 to 0.55), PCI (OR 0.66, 95% CI 0.64 to 0.67), or repeat CABG (OR 0.11, 95% CI 0.10 to 0.12). Moreover, the risk of in-hospital mortality was higher in the previous CABG group (OR 1.15, 95% CI 1.10 to 1.21). In the subset of patients who were revascularized in both groups, this excess mortality was no longer observed (OR 0.82, 95% CI 0.66 to 1.03). In conclusion, a previous CABG in patients who present with NSTEMI is associated with lower rates of invasive procedures and revascularization and higher in-hospital mortality than patients without a previous CABG.

Acute Coronary Syndromes Among Patients with Prior Coronary Artery Bypass Surgery

PURPOSE OF REVIEW

Acute coronary syndromes (ACS) often occur in individuals with prior coronary artery bypass graft surgery (CABG). Our goal was to describe the prevalence, clinical characteristics, prognosis, and treatment strategies in this group of patients.

RECENT FINDINGS

Studies demonstrate that both acute and long-term major adverse cardiovascular outcomes are increased in patients with ACS and prior CABG compared to those without CABG. Much of this risk is attributed to the greater comorbid conditions present in patients with prior CABG. Data regarding optimal management of ACS in patients with prior CABG are limited, but most observational studies favor an early invasive approach for treatment. Native vessel percutaneous coronary intervention (PCI), if feasible, is generally preferred to bypass graft PCI. Patients with ACS and prior CABG represent a high-risk group of individuals, and implementing optimal preventive and treatment strategies are critically important to reduce the risk.

Cardiac catheterizations in patients with acute coronary syndrome and prior coronary bypass surgery: Impact of native vs graft vs absent culprit lesions on clinical outcomes and treatment strategy

BACKGROUND

In patients with prior coronary artery bypass graft surgery (CABG), acute coronary syndrome (ACS) is not uncommon. This study investigated treatment strategy and compared clinical outcomes for native, graft and absent culprit lesions.

METHODS

Single-center retrospective cohort study. From July 2010 to July 2019, 642 consecutive ACS patients with prior CABG were screened for eligibility. The primary endpoint was major adverse cardiovascular events (MACE) at 1 year, a composite of all-cause mortality, myocardial infarction, stroke and ischemia-driven revascularization.

RESULTS

A total of 549 patients were included, with 215 (39.2 %) having native culprits, 256 (46.6 %) graft culprits and 78 (14.2 %) no clear culprits. Patients with native culprits were treated with native PCI in 94.0 %, re-CABG in 0.9 % and optimal medical therapy (OMT) in 5.1 %. Patients with graft culprits were treated with native PCI in 14.1 %, graft PCI in 81.2 %, re-CABG in 0.8 % and OMT in 3.9 %. All patients without a clear culprit received OMT. The cumulative incidence of 1-year MACE was 24.7 % for native vs 26.2 % for graft vs 21.8 % for absent culprits. Kaplan-Meier curves did not differ significantly. In patients with graft culprit, no significant difference in 1-year MACE was observed between native PCI and graft PCI (30.6 % vs 25.5 %, p = 0.36).

CONCLUSIONS

This retrospective study shows that in ACS patients with prior CABG, MACE occured frequently and was comparable for native, graft and absent culprits. Native PCI as treatment strategy for patients with a graft culprit was relatively common, with no significant difference in MACE as compared to graft PCI.

Cardiovascular Risk Profile, Presentation and Management Outcomes of Patients with Acute Coronary Syndromes after Coronary Artery Bypass Grafting

BACKGROUND

Coronary artery bypass (CABG) is an important revascularization procedure with excellent long-term results. However, bypass grafts, particularly venous grafts, develop structural changes and atherosclerotic plaques that may cause angina or even acute coronary syndromes (ACS). Here we aimed to study patients with previous CABG presenting with an ACS and evaluated their cardiovascular (CV) risk profile, clinical presentations, angiographic findings, management strategies and short and long term outcomes.

PATIENTS AND METHODS

This represents an observational retrospective cross sectional single center study including all consecutive patients with previous CABG presenting with ACS at the University Heart Center of the University Hospital Zurich, Switzerland between January 1, 2000 and December 31, 2016. Mean age was 76.4 years and 83.1% were males. Major adverse cardiovascular and cerebrovascular events (MACCE) at 1-year follow up and long-term follow up were analyzed using Kaplan Meyer survival analysis.

RESULTS

We included 510 patients with ACS and prior CABG. Most patients were elderly at the time of presentation. 60.2% were diabetics and 58.6% obese, 43.5% hypertensives and 37.8% had hyperlipidemia. 73% (n=372) presented as unstable angina (UA), 22.5% as NSTEMI (n=115) and only 4.5% as STEMI (n=23). The acute events occurred in 4.9% (n=25) before discharge, in 4.9% (n=25) within the first year and in 90.2% (n=460) thereafter. Most of the patients (92.2%; n=470) had stenosed or occluded venous bypass grafts at presentation, while a minority (7.8%; n=40) had significantly narrowed or occluded arterial grafts. CV risk profiles were similar in both groups. However, arterial graft disease occurred earlier after CABG and more likely presented as NSTEMI rather than UA compared to the SVG group. In 54.7% (n=279) primary PCI of the saphenous graft, and in 13.5% (n=69) of the native coronary arteries was performed, while 6.5% (n=33) underwent redo CABG and 25.3% (n=129) received medical treatment only. MACE at 1 year occurred in 12.2% (n=62) with repeated revascularization as the most common event (7.2%; n=37) followed by cardiac death (2.4%; n=12), MI (1.2%; n=6), cerebrovascular infarction (1.2%; n=6) and major bleeding (0.2%; n=1). Hypertensive and obese patients, those with myocardial infarction or an ACS before discharge or during the first year after CABG had higher MACCE. In patients undergoing pPCI the rate of cardiac death and MI at 1 year was lower with an intervention in the native coronary arteries and with redo CABG compared to pPCI of bypass grafts.

CONCLUSION

Thus, patients with ACS and prior CABG typically present as UA and much less frequently as NSTEMI-ACS and particularly STEMI. Most events occur after one year, particularly with SVG. The 1 year MACCE rate is comparable to those with native coronary artery ACS. Hypertensive and obese patients, those with MI or with an ACS before discharge had higher MACCE rates.

Clinical Characteristics, Management Strategies, and Outcomes of Non-ST-Segment-Elevation Myocardial Infarction Patients With and Without Prior Coronary Artery Bypass Grafting

Background

There are limited data on the management strategies, temporal trends and clinical outcomes of patients who present with non–ST‐segment–elevation myocardial infarction and have a prior history of CABG.

Methods and Results

We identified 287 658 patients with non–ST‐segment–elevation myocardial infarction between 2010 and 2017 in the United Kingdom Myocardial Infarction National Audit Project database. Clinical and outcome data were analyzed by dividing into 2 groups by prior history of coronary artery bypass grafting (CABG): group 1, no prior CABG (n=262 362); and group 2, prior CABG (n=25 296). Patients in group 2 were older, had higher GRACE (Global Registry of Acute Coronary Events) risk scores and burden of comorbid illnesses. More patients underwent coronary angiography (69% versus 63%) and revascularization (53% versus 40%) in group 1 compared with group 2. Adjusted odds of receiving inpatient coronary angiogram (odds ratio [OR], 0.91; 95% CI, 0.88–0.95; P<0.001) and revascularization (OR, 0.73; 95% CI, 0.70–0.76; P<0.001) were lower in group 2 compared with group 1. Following multivariable logistic regression analyses, the OR of in‐hospital major adverse cardiovascular events (composite of inpatient death and reinfarction; OR, 0.97; 95% CI, 0.90–1.04; P=0.44), all‐cause mortality (OR, 0.96; 95% CI, 0.88–1.04; P=0.31), reinfarction (OR, 1.02; 95% CI, 0.89–1.17; P=0.78), and major bleeding (OR, 1.01; 95% CI, 0.90–1.11; P=0.98) were similar across groups. Lower adjusted risk of inpatient mortality (OR, 0.67; 95% CI, 0.46–0.98; P=0.04) but similar risk of bleeding (OR,1.07; CI, 0.79–1.44; P=0.68) and reinfarction (OR, 1.13; 95% CI, 0.81–1.57; P=0.47) were observed in group 2 patients who underwent percutaneous coronary intervention compared with those managed medically.

Conclusions

In this national cohort, patients with non–ST‐segment–elevation myocardial infarction with prior CABG had a higher risk profile, but similar risk‐adjusted in‐hospital adverse outcomes compared with patients without prior CABG. Patients with prior CABG who received percutaneous coronary intervention had lower in‐hospital mortality compared with those who received medical management.

Issues in Designing and Interpreting Small Clinical Trials

The randomised controlled trial (RCT) is a powerful approach for testing the effectiveness of various clinical interventions. Cardiology often benefits from large RCTs, which may be used to inform practice decisions ranging from primary prevention to advanced cardiac disease and/or acute cardiac care. RCTs in cardiology often need to be quite large to test for meaningful effects on clinical outcomes, because effect sizes are typically modest and clinical outcomes may take several years to occur after treatment initiation. However, a variety of small clinical trials are also carried out in the biomedical research enterprise; these are often difficult to design and interpret, because the objectives and needs of small clinical trials are quite variable. Some are pilot trials that may be used to refine processes or as part of the planning in advance of a larger trial designed to test therapeutic efficacy. Some are first-in-human or proof-of-concept studies that, also, will eventually be followed by one or more larger trials to test therapeutic efficacy. Some are intended to be stand-alone trials that are small for other reasons. In this paper, we explore some key issues related to design and interpretation of small clinical trials in cardiology. We broadly classify small trials into 4 types: 1) pilot trials, 2) early-stage or proof-of-concept trials, 3) rare diseases or difficult-to-recruit populations, and 4) underpowered trials. For each, we describe the appropriate objectives, analysis, and interpretation.

Outcome of patients with prior coronary bypass surgery admitted with an acute coronary syndrome

BACKGROUND

Patients with prior coronary artery bypass graft surgery (CABG) are at increased risk for recurrent cardiovascular ischaemic events. Advances in management have improved prognosis of patients with acute coronary syndrome (ACS), yet it is not known whether similar trends exist in patients with prior CABG.

AIM

Examine temporal trends in the prevalence, treatment and clinical outcomes of patients with prior CABG admitted with ACS.

METHODS

Time-dependent analysis of patients with or without prior CABG admitted with an ACS who enrolled in the ACS Israeli Surveys between 2000 and 2016. Surveys were divided into early (2000-2008) and late (2010-2016) time periods. Outcomes included 30 days major adverse cardiac events (30d MACE) (death, myocardial infarction, stroke, unstable angina, stent thrombosis, urgent revascularisation) and 1-year mortality.

RESULTS

Among 15 152 patients with ACS, 1506 (9.9%) had a prior CABG. Patients with prior CABG were older (69 vs 63 years), had more comorbidities and presented more with non-ST elevation-ACS (82% vs 51%). Between time periods, utilisation of antiplatelets, statins and percutaneous interventions significantly increased in both groups (p<0.001 for each). The rate of 30d MACE decreased in patients with (19.1%-12.4%, p=0.001) and without (17.4%-9.5%, p<0.001) prior CABG. However, 1-year mortality decreased only in patients without prior CABG (10.5% vs 7.4%, p<0.001) and remained unchanged in patients with prior CABG. Results were consistent after propensity matching.

CONCLUSIONS

Despite an improvement in the management and prognosis of patients with ACS in the last decade, the rate of 1-year mortality of patients with prior CABG admitted with an ACS remained unchanged.

Clinical Characteristics, Management Strategies and Outcomes of Acute Myocardial Infarction Patients With Prior Coronary Artery Bypass Grafting

OBJECTIVE

To investigate the management strategies, temporal trends, and clinical outcomes of patients with a history of coronary artery bypass graft (CABG) surgery and presenting with acute myocardial infarction (MI).

PATIENTS AND METHODS

We undertook a retrospective cohort study using the National Inpatient Sample database from the United States (January 2004-September 2015), identified all inpatient MI admissions (7,250,768 records) and stratified according to history of CABG (group 1, CABG-naive [94%]; group 2, prior CABG [6%]).

RESULTS

Patients in group 2 were older, less likely to be female, had more comorbidities, and were more likely to present with non-ST-elevation myocardial infarction compared with group 1. More patients underwent coronary angiography (68% vs 48%) and percutaneous coronary intervention (PCI) (44% vs 26%) in group 1 compared with group 2. Following multivariable logistic regression analyses, the adjusted odd ratio (OR) of in-hospital major adverse cardiovascular and cerebrovascular events (OR, 0.98; 95% CI, 0.95 to 1.005; P=.11), all-cause mortality (OR, 1; 95% CI, 0.98 to 1.04; P=.6) and major bleeding (OR, 0.99; 95% CI, 0.94 to 1.03; P=.54) were similar to group 1. Lower adjusted odds of in-hospital major adverse cardiovascular and cerebrovascular events (OR, 0.64; 95% CI, 0.57 to 0.72; P<.001), all-cause mortality (OR, 0.45; 95% CI, 0.38 to 0.53; P<.001), and acute ischemic stroke (OR, 0.71; 95% CI, 0.59 to 0.86; P<.001) were observed in group 2 patients who underwent PCI compared with those managed medically without any increased risk of major bleeding (OR, 1.08; 95% CI, 0.94 to 1.23; P=.26).

CONCLUSIONS

In this national cohort, MI patients with prior-CABG had a higher risk profile, but similar in-hospital adverse outcomes compared with CABG-naive patients. Prior-CABG patients who received PCI had better in-hospital clinical outcomes compared to those who received medical management.

Characteristics and Outcome of Patients ≥75 Years of Age With Prior Coronary Artery Bypass Grafting Admitted for an Acute Coronary Syndrome

The prognostic role of previous coronary artery bypass (CABG) in elderly patients admitted to hospital for an acute coronary syndrome (ACS) is unclear. Therefore, the aim of this study was to compare the prognosis of patients aged ≥75 years admitted for an ACS with or without previous history of CABG. The primary outcome of the study was a composite of overall mortality, recurrent nonfatal myocardial infarction, nonfatal stroke, and rehospitalization for heart failure at 1-year follow-up. We included 2,253 ACS patients, aged 81 (78 to 85) years enrolled in 3 multicenter studies (the Italian Elderly ACS study, the LADIES ACS study, and the Elderly ACS 2 randomised trial) - 178 (7.9%) with previous CABG, 2,075 (92.1%) without. Patients with previous CABG had a higher burden of cardiovascular risk factors, lower ejection fraction, and higher creatinine values on admission. However, both at univariate analysis and after adjustment for the most relevant covariates (sex, age, previous myocardial infarction, type of ACS, left ventricular ejection fraction, and serum creatinine on admission), previous CABG did not show any statistically significant association with 1-year outcome (adjusted hazard ratio 0.85; 95% confidence interval 0.61 to 1.19; p = 0.353). In conclusion, our study suggests that elderly ACS patients with previous CABG have worse basal clinical characteristics. Nevertheless, in a broad cohort of patients mostly treated with percutaneous coronary intervention during the index event, previous CABG did not confer independent additional risk of major adverse cardiovascular events at 1-year follow-up.