Coronary artery bypass grafting versus medical therapy in patients with stable coronary artery disease: An individual patient data pooled meta-analysis of randomized trials

Revascularization in chronic coronary syndrome: shifts in clinical practice guidelines

PURPOSE OF REVIEW

The optimal revascularization strategy for chronic coronary syndrome (CCS) is rapidly evolving due to emerging evidence and technological advancements. This review will discuss the guidelines for the management of CCS, examining how they align with and respond to recent high-quality studies. We will also discuss the evolution of the guidelines and highlight key differences.

RECENT FINDINGS

While broad consensus exists between the most recent European and American guidelines, notable differences exist in the management of multivessel disease with preserved ejection fraction and left main disease. The role of the Heart Teams has become increasingly vital particularly when the guidelines do not fit the clinical scenarios, and the evidence is controversial.

SUMMARY

Determining the optimal management strategy for patients with CCS requires careful consideration of anatomic complexity, comorbidities, and individual patient preferences. While advances in percutaneous coronary intervention (PCI) and medical therapy have been widely discussed, it is equally important to contextualize these with emerging innovations in surgical revascularization. Techniques such as multiple arterial grafting and minimally invasive surgical approaches represent significant progress in coronary artery bypass surgery. Randomized trials that compare state-of-the-art percutaneous and surgical revascularization techniques are thus needed.

Impact of Myocardial Hibernation and Scar on Benefits From CABG in Ischemic Left Ventricular Dysfunction

BACKGROUND

The significance of evaluating myocardial viability in making decisions regarding coronary artery bypass grafting (CABG) for patients with ischemic left ventricular dysfunction (ILVD) remains controversial. This study aimed to examine the impact of integrated assessment of hibernating myocardium and scars on the survival benefit associated with CABG in patients with ILVD.

METHODS

Consecutive patients with ILVD who underwent fluorine-18 fluorodeoxyglucose positron emission tomography and cardiac magnetic resonance imaging with late gadolinium enhancement viability testing from January 2015 and April 2018 were retrospectively enrolled. The primary end point was all-cause death. The secondary end point was a composite of cardiovascular death, cardiovascular hospitalization, heart transplantation, revascularization, insertion of an implantable cardioverter-defibrillator, or nonfatal stroke. Cox models calculated hazard ratios (HRs) and CIs for CABG vs medical therapy alone for subgroups with different levels of hibernation and scars.

RESULTS

During a median follow-up of 71.5 months in 507 patients, 98 patients reached the primary end point and 194 reached the secondary end point. After adjustment, CABG was associated with lower risks of all-cause mortality (HR, 0.249; 95% CI, 0.154-0.428; P<.001) and lower incidences of secondary outcomes (HR, 0.457; 95% CI, 0.318-0.658; P<.001) compared with medical treatment alone in the population. Across all 4 subgroups classified by the optimal cutoff value (10% hibernation and 26% scar), CABG was associated with favorable outcomes regardless of the hibernation and scar level.

CONCLUSIONS

The extent and severity of hibernating myocardium and scars appear not to influence the effects of CABG in patients with ILVD.

Cardiac Surgery 2024 Reviewed

For the 11th consecutive time, we systematically reviewed the cardio-surgical literature for the past year (2024), using the PRISMA approach for a results-oriented summary. In 2024, the discussion on the value of randomized and registry evidence increased, triggered by consistent findings in the field of coronary artery disease (CAD) and discrepant results in structural heart disease. The literature in 2024 again confirmed the excellent long-term outcomes of CABG compared with PCI in different scenarios, generating further validation for the CABG advantage reported in randomized studies. This has been reflected in the new guidelines for chronic CAD in 2024. Two studies indicate novel perspectives for CABG, showing that cardiac shockwave therapy in CABG improves myocardial function in ischemic hearts and that CABG guided by computed tomography is safe and feasible. For aortic stenosis, an early advantage for transcatheter (TAVI) compared with surgical (SAVR) treatment has found more support; however, long-term TAVI results keep being challenged, this year by new FDA and registry data in favor of SAVR. For failed aortic valves, redo-SAVR showed superior results compared with valve-in-valve TAVI. In the mitral field, studies showed short-term noninferiority for transcatheter treatment compared with surgery for secondary mitral regurgitation (MR), and significant long-term survival benefit in registries with surgery for primary MR. Finally, surgery was associated with better survival compared with medical therapy for acute type A aortic intramural hematoma. This article summarizes publications perceived as important by us. It cannot be complete nor free of individual interpretation but provides up-to-date information for patient-specific decision-making.

Long-Term Survival After Coronary Artery Bypass Graft Surgery

BACKGROUND

Management guidelines for stable 3-vessel coronary artery disease have become a subject of debate. We aim to provide a benchmark for the survival of patients with normal ejection fraction, stable 3-vessel disease, and elective coronary artery bypass graft (CABG) surgery.

METHODS

Data from consecutive patients with normal ejection fraction undergoing elective primary isolated CABG for 3-vessel disease in a diverse 11-center surgical network between 2008 and 2020 were analyzed. Survival data were obtained from the Centers for Disease Control and Prevention National Death Index and compared with an age- and sex-matched United States population. Mixed-effects modeling with "hospital" as a random effect was used to evaluate factors associated with all-cause mortality.

RESULTS

Of 4061 patients included in this analysis, 893 (22%) were women, and the median age was 68 years (interquartile range, 61-74 years). Patients with elective CABG surgery for 3-vessel disease and normal ejection fraction demonstrated improved survival compared with an age- and sex-matched United States population, with significantly increasing relative survival over time. Factors associated with mortality included age ≥65 years (hazard ratio [HR], 1.71; P < .001), male sex (HR, 1.32; P = .028), diabetes (HR, 1.4; P = .002), dialysis (HR, 2.41; P = .03), moderate or severe chronic lung disease (HR, 1.68; P < .001), and peripheral arterial disease (HR, 2.05; P < .001).

CONCLUSIONS

Patients with stable 3-vessel disease and normal ejection fraction who underwent elective CABG demonstrated improved survival compared with an age- and sex-matched United States population. With this benchmark, further research can better elucidate the relative role of surgery and medical therapy in this patient population.

Long-term Survival in Elderly Patients after Coronary Artery Bypass Grafting Compared to the Age-matched General Population: A Meta-analysis of Reconstructed Time-to-Event Data

BACKGROUND

 Coronary artery disease (CAD) limits life expectancy compared to the general population. Myocardial infarctions (MIs) are the primary cause of death. The incidence of MI increases progressively with age and most MI deaths occur in the population older than 70 years. Coronary artery bypass grafting (CABG) may prevent the occurrence of new MIs by bypassing most CAD lesions, providing downstream "collateralization" to the diseased vessel, and consequently prolonging survival. We systematically assessed the survival-improving potential of CABG by comparing elderly CABG patients to the age-matched general population.

METHODS

 Three databases were assessed. The primary and single outcome was long-term all-cause mortality. Time-to-event data of the individual studies were extracted and reconstructed in an overall survival curve. As a sensitivity analysis, summary hazard ratios (HRs) and 95% confidence intervals (CIs) for all individual studies were pooled and meta-analytically addressed. The control group was based on the age-matched general population of each individual study.

RESULTS

 From 1,352 records, 4 studies (4,045 patients) were included in the analysis. Elderly patients (>70 years) who underwent CABG had a significantly lower risk of death in the follow-up compared to the general age-matched population in the overall survival analysis (HR: 0.88; 95% CI: 0.83, 0.94; p < 0.001: mean follow-up was 7 years).

CONCLUSION

 Elderly patients who undergo CABG appear to have significantly better long-term survival compared to the age-matched general population. This advantage becomes visible after the first year and underscores the life-prolonging effect of bypass surgery, which may eliminate the expected reduction in life expectancy through CAD.

Outcomes with revascularisation versus conservative management of participants with 3-vessel coronary artery disease in the ISCHEMIA trial

BACKGROUND

Whether revascularisation (REV) improves outcomes in patients with three-vessel coronary artery disease (3V-CAD) is uncertain.

AIMS

Our objective was to evaluate outcomes with REV (percutaneous coronary intervention [PCI] or coronary artery bypass graft surgery [CABG]) versus medical therapy in patients with 3V-CAD.

METHODS

ISCHEMIA participants with 3V-CAD on coronary computed tomography angiography without prior CABG were included. Outcomes following initial invasive management (INV) with REV (PCI or CABG) versus initial conservative management (CON) with medical therapy alone were evaluated. Regression modelling was used to estimate the outcomes if all participants were to undergo prompt REV versus those assigned to CON. Outcomes were cardiovascular (CV) death/myocardial infarction (MI), death, CV death, and quality of life. Bayesian posterior probability for benefit (Pr [benefit]) for 1 percentage point lower 4-year rates with REV versus CON were evaluated.

RESULTS

Among 1,236 participants with 3V-CAD (612 INV/624 CON), REV was associated with lower 4-year CV death/MI (adjusted 4-year difference: -4.4, 95% credible interval [CrI] -8.7 to -0.3 percentage points, Pr [benefit]=94.8%) when compared with CON, with similar results for PCI versus CON (-5.8, 95% CrI: -10.8 to -0.5 percentage points, Pr [benefit]=96.4%) and CABG versus CON (-3.7, 95% CrI: -8.8 to 1.5 percentage points, Pr [benefit]=84.7%). Adjusted 4-year REV versus CON differences were as follows: death -1.2 (95% CrI: -4.7 to 2.2) percentage points, CV death -2.3 (95% CrI: -5.5 to 0.8) percentage points, with similar results for PCI and for CABG. The Pr (benefit) for death with REV (PCI or CABG) versus CON was 49-63%. The adjusted 12-month Seattle Angina Questionnaire-7 summary score differences favoured REV: REV versus CON 4.6 (95% CrI: 2.7-6.4) percentage points; PCI versus CON 3.6 (95% CrI: 1.2-5.8) percentage points and CABG versus CON 4.3 (95% CrI: 1.5-6.9) percentage points with high Pr (benefit).

CONCLUSIONS

In participants with 3V-CAD, REV (either PCI or CABG) was associated with a lower 4-year CV death/MI rate and improved quality of life, with similar results for PCI versus CON and CABG versus CON. The differences in all-cause mortality between REV and CON were small with wide confidence intervals. (ClinicalTrials.gov: NCT01471522).

Statistical primer: individual patient data meta-analysis and meta-analytic approaches in case of non-proportional hazards

Individual patient data (IPD) meta-analyses build upon traditional (aggregate data) meta-analyses by collecting IPD from the individual studies rather than using aggregated summary data. Although both traditional and IPD meta-analyses produce a summary effect estimate, IPD meta-analyses allow for the analysis of data to be performed as a single dataset. This allows for standardization of exposure, outcomes, and analytic methods across individual studies. IPD meta-analyses also allow the utilization of statistical methods typically used in cohort studies, such as multivariable regression, survival analysis, propensity score matching, uniform subgroup and sensitivity analyses, better management of missing data, and incorporation of unpublished data. However, they are more time-intensive, costly, and subject to participation bias. A separate issue relates to the meta-analytic challenges when the proportional hazards assumption is violated. In these instances, alternative methods of reporting time-to-event estimates, such as restricted mean survival time should be used. This statistical primer summarizes key concepts in both scenarios and provides pertinent examples.

Current concepts in coronary artery revascularisation

Coronary artery revascularisation can be performed surgically or percutaneously. Surgery is associated with higher procedural risk and longer recovery than percutaneous interventions, but with long-term reduction of recurrent cardiac events. For many patients with obstructive coronary artery disease in need of revascularisation, surgical or percutaneous intervention is indicated on the basis of clinical and anatomical reasons or personal preferences. Medical therapy is a crucial accompaniment to coronary revascularisation, and data suggest that, in some subsets of patients, medical therapy alone might achieve similar results to coronary revascularisation. Most revascularisation data are based on prevalently White, non-elderly, male populations in high-income countries; robust data in women, older adults, and racial and other minorities, and from low-income and middle-income countries, are urgently needed.

2021 Coronary Revascularization Guidelines-Lessons in the Importance of Data Scrutiny and Reappraisal of Evidence

This Viewpoint discusses whether or not the evidence cited in the 2021 American College of Cardiology/American Heart Association/Society for Cardiovascular Angiography &amp;amp; Interventions guidelines for coronary artery revascularization support downgrading coronary artery bypass grafting relative to medical therapy.