Viability and Outcomes With Revascularization or Medical Therapy in Ischemic Ventricular Dysfunction: A Prespecified Secondary Analysis of the REVIVED-BCIS2 Trial

Left Ventricular Ejection Fraction Change Following Percutaneous Coronary Intervention: Correlates and Association With Prognosis

BACKGROUND

The association between left ventricular ejection fraction (LVEF) change (ΔLVEF) following percutaneous coronary intervention (PCI) and the long-term mortality rate in patients with coronary artery disease is incompletely investigated. We aimed to assess the impact of PCI on LVEF and the association of ΔLVEF after PCI with the long-term mortality rate.

METHODS AND RESULTS

This observational study included 8181 patients with paired angiographic LVEF measurements performed at baseline and 6 to 8 months following the index PCI. ΔLVEF was defined as LVEF measured on the 6- to 8-month angiography minus LVEF measured on the baseline angiography. LVEF change was classified according to the following categories: reduced (ΔLVEF <0), mildly improved (ΔLVEF >0% to <10%) and largely improved (ΔLVEF ≥10%). The primary outcome was the 5-year mortality rate. In patients with baseline LVEF <40%, 40% to <50% and ≥50%, ΔLVEF (median [25th-75th percentiles]) was 6.0% [0.0% to 14.0%], 4.0% [-1.0% to 11.0%] and 0.0% [-4.0% to 3.0%], respectively (P<0.001). In patients with reduced, mildly improved, and largely improved ΔLVEF, the 5-year mortality rate (n=712) was 29.1%, 23.1%, and 16.5%, respectively, in patients with baseline LVEF <40%; 17.0%, 12.2% and 9.8%, respectively, in patients with baseline LVEF 40% to <50%; and 7.8%, 7.1%, and 5.6%, respectively, in patients with baseline LVEF ≥50% (adjusted hazard ratio [HR], 0.91 [95% CI, 0.86-0.96]; P<0.001) for all-cause death and adjusted (HR, 0.86 [95% CI, 0.81-0.92]; P<0.001) for cardiac death, calculated for 5% higher ΔLVEF.

CONCLUSIONS

In patients with coronary artery disease undergoing PCI, improvement of LVEF following PCI was associated with a reduced long-term mortality rate in patients with reduced LVEF but not in patients with preserved LVEF before intervention.

Revascularization and outcomes in ischaemic left ventricular dysfunction after heart failure admission: The RevascHeart study

AIMS

Despite numerous trials on revascularization in patients with heart failure (HF) and ischaemic left ventricular (LV) dysfunction, its role remains unsettled. Guideline-directed medical therapy (GDMT) for HF has shown benefits on outcomes. This multicentre study aims to compare long-term mortality between revascularization and GDMT in patients with ischaemic LV dysfunction following admission for HF.

METHODS AND RESULTS

Between 2012 and 2023, 408 patients admitted for HF with a LV ejection fraction (LVEF) of 40% or less and documented coronary artery disease (CAD) were included. Patients were categorized into two groups based on their initial treatment decision: revascularization (percutaneous coronary intervention [PCI] or coronary artery bypass graft [CABG]) or GDMT. The primary outcome was rate of all-cause or cardiovascular mortality, and secondary outcomes included type of revascularization (PCI vs. CABG) and LV reverse remodelling. After a median 44.6-month follow-up, 100 patients (33%) died in the revascularization group, compared to 44 (43%) in the GDMT group. Multivariate analysis showed no significant benefit of revascularization on all-cause mortality (hazard ratio [HR] 0.81, 95% confidence interval [CI] 0.48-1.39, p = 0.45) or cardiovascular mortality (HR 0.97, 95% CI 0.62-1.52, p = 0.90) compared to GDMT. Neither CABG (HR 0.74, 95% CI 0.51-1.08, p = 0.13) nor PCI (HR 0.98, 95% CI 0.62-1.55, p = 0.93) demonstrated a mortality reduction compared to GDMT. Both groups experienced significant reductions in LV size and improvements in LVEF, greater in the revascularization group.

CONCLUSION

Revascularization did not outperform GDMT in ischaemic LV dysfunction following HF admission in this retrospective analysis. Larger prospective studies are needed to clarify the potential role of revascularization in improving outcomes.

Propensity score-based comparison of high-risk coronary artery bypass grafting vs. left ventricular assist device implantation in patients with coronary artery disease and advanced heart failure

Objectives

Revascularization in patients with severely reduced left ventricular function and coronary artery disease (CAD) is associated with a high perioperative risk. In this setting, implantation of a durable left ventricular assist device (LVAD) might be an alternative.

Methods

We retrospectively compared the outcomes of adult patients with CAD and a left ventricular ejection fraction (LVEF) ≤ 25% who underwent coronary artery bypass grafting (CABG) vs. LVAD implantation. Propensity score (PS) matching was performed for statistical analysis, resulting in 168 pairs.

Results

In the PS-matched cohorts, the mean age was 62 years; one third had a history of myocardial infarction, 11% were resuscitated, half of the patients were on inotropic support, and 20% received preoperative mechanical circulatory support. LVAD patients required significantly longer ventilation (58 h [21, 256] vs. 16 h [9, 73], p < 0.001) and had a longer ICU stay (11d [7, 24] vs. 4d [2, 10], p ≤ 0.001) compared to CABG patients The incidence of postoperative renal replacement therapy (2 [1.2%] vs.15 [8.9%], p = 0.002) and temporary mechanical circulatory support was lower in the LVAD group (1 [0.6%] vs. 51 [30.4%], p ≤ 0.001). The in-hospital stroke rate was similar (LVAD 7 [5.4%] vs. CABG 8 [6.2%], p = 0.9). In-hospital survival, 1-year survival, and 3-year survival were 90.5% vs. 85.5% (p = 0.18), 77.4% vs. 68.9% (p = 0.10) and 69.6% vs. 45.9% (p < 0.001), for CABG and LVAD patients respectively.

Conclusion

Patients with CAD and advanced HF demonstrate better mid-term survival if they undergo CABG rather than LVAD implantation.

Imaging Advances in Heart Failure

This paper delves into the significance of imaging in the diagnosis, aetiology and therapeutic guidance of heart failure, aiming to facilitate early referral and improve patient outcomes. Imaging plays a crucial role not only in assessing left ventricular ejection fraction, but also in characterising the underlying cardiac abnormalities and reaching a specific diagnosis. By providing valuable data on cardiac structure, function and haemodynamics, imaging helps diagnose the condition, evaluate haemodynamic status and, consequently, identify the underlying pathophysiological phenotype, as well as stratifying the risk for outcomes. In this article, we provide a comprehensive exploration of these aspects.

Molecular Imaging of Heart Failure: An Update and Future Trends

Molecular imaging can detect and quantify pathophysiological processes underlying heart failure, complementing evaluation of cardiac structure and function with other imaging modalities. Targeted tracers have enabled assessment of various cellular and subcellular mechanisms of heart failure aiming for improved phenotyping, risk stratification, and personalized therapy. This review outlines the current status of molecular imaging in heart failure, accompanied with discussion on novel developments. The focus is on radionuclide methods with data from clinical studies. Imaging of myocardial metabolism can identify left ventricle dysfunction caused by myocardial ischemia that may be reversible after revascularization in the presence of viable myocardium. In vivo imaging of active inflammation and amyloid deposition have an established role in the detection of cardiac sarcoidosis and transthyretin amyloidosis. Innervation imaging has well documented prognostic value in predicting heart failure progression and arrhythmias. Tracers specific for inflammation, angiogenesis and myocardial fibrotic activity are in earlier stages of development, but have demonstrated potential value in early characterization of the response to myocardial injury and prediction of cardiac function over time. Early detection of disease activity is a key for transition from medical treatment of clinically overt heart failure towards a personalized approach aimed at supporting repair and preventing progressive cardiac dysfunction.

Efficacy of revascularization in CTO patients based on hibernating myocardium therapy

BACKGROUND

The effectiveness of percutaneous coronary intervention (PCI) for chronic total occlusion (CTO) is still uncertain, especially for patients with ischemic left ventricular dysfunction. This study aimed to assess hibernating myocardium (HM), as determined by single-photon emission computed tomography (SPECT) and 18F-FDG positron emission tomography (PET), and to compare the benefits of PCI and optimal medical therapy (OMT).

METHODS

A retrospective study collected data from 332 patients with CTO and ischemic left ventricular dysfunction. The study compared patients who underwent PCI or OMT via propensity score matching (PSM) analysis which was performed with a 1:2 matching protocol using the nearest neighbour matching algorithm. The primary endpoint of the study was the occurrence of major adverse cardiac events (MACE), defined as a composite of cardiac death, readmission for worsening heart failure (WHF), revascularization and myocardial infarction (MI).

RESULTS

After PSM, there were a total of 246 individuals in the PCI and OMT groups. Following Cox regression, hibernating myocardium/total perfusion defect (HM/TPD) was identified as an independent risk factor (hazard ratio (HR): 1.03, 95% confidence interval (CI): 1.008-1.052, p = .007). The cut-off value of HM/TPD was 38%. The results of the subgroup analysis suggest that for patients with HM/TPD >38%, the OMT group had a greater risk of MACE (p = .035). A sensitivity analysis restricting patients with single-vessel CTO lesions, HM/TPD remained an independent predictor (HR 1.025, 95% CI 1.008-1.043, p = .005).

CONCLUSION

HM/TPD is an independent predictor of MACE, and for patients with HM/TPD > 38%, CTO-PCI had a lower risk of MACE compared with OMT. However, further validation is still needed through large-scale studies.

Prognostic Value of Estimated Glucose Disposal Rate and Systemic Immune-Inflammation Index in Non-Diabetic Patients Undergoing PCI for Chronic Total Occlusion

BACKGROUND AND OBJECTIVES

Chronic total occlusion (CTO) is a complex lesion of coronary artery disease (CAD) with a detection rate of approximately 25% on coronary angiography. CTO patients generally experience poor quality of life and prognosis. This study aims to evaluate the association between the estimated glucose disposal rate (eGDR), a surrogate marker for insulin resistance (IR), and the prognosis of CTO PCI patients, as well as to investigate the potential role of the systemic immune-inflammation index (SII) in this process.

METHODS

We retrospectively included 1482 non-diabetic patients who underwent successful CTO PCI at Anzhen Hospital between January 2018 and December 2021. The primary endpoint was major adverse cardiovascular events (MACEs). Clinical characteristics, biochemical markers, and interventional records were collected, and the eGDR and SII were calculated. Cox regression, restricted cubic splines (RCSs), receiver operating characteristic (ROC) analysis, and Kaplan-Meier curves were used to assess associations.

RESULTS

MACEs occurred in 158 patients (10.67%). Patients with MACEs had lower eGDR and higher SII levels. A high eGDR significantly reduced MACE risk (Q4 vs. Q1: HR 0.06, 95% CI 0.03-0.12), while a high SII increased it (Q4 vs. Q1: HR 3.32, 95% CI 1.78-6.33). The combination of low eGDRs and high SIIs predicted the highest MACE risk (HR 4.36, 95% CI 2.71-6.01). The SII partially mediated the relationship between eGDR and MACEs.

CONCLUSIONS

A low eGDR and high SII are significant predictors of poor prognosis in non-diabetic CTO PCI patients. Combining the eGDR and the SII provides a comprehensive assessment for better predicting cardiovascular outcomes.

Impact of Anatomical and Viability-Guided Completeness of Revascularization on Clinical Outcomes in Ischemic Cardiomyopathy

BACKGROUND

Complete revascularization of coronary artery disease has been linked to improved outcomes in patients with preserved left ventricular (LV) function.

OBJECTIVES

This study sought to identify the impact of complete revascularization in patients with severe LV dysfunction.

METHODS

Patients enrolled in the REVIVED-BCIS2 (Revascularization for Ischemic Ventricular Dysfunction) trial were eligible if baseline/procedural angiograms and viability studies were available for analysis by independent core laboratories. Anatomical and viability-guided completeness of revascularization were measured by the coronary and myocardial revascularization indices (RIcoro and RImyo), respectively, where RIcoro = (change in British Cardiovascular Intervention Society Jeopardy score [BCIS-JS]) / (baseline BCIS-JS) and RImyo= (number of revascularized viable segments) / (number of viable segments supplied by diseased vessels). The percutaneous coronary intervention (PCI) group was classified as having complete or incomplete revascularization by median RIcoro and RImyo. The primary outcome was death or hospitalization for heart failure.

RESULTS

Of 700 randomized patients, 670 were included. The baseline BCIS-JS and SYNTAX (Synergy Between PCI With Taxus and Cardiac Surgery) scores were 8 (Q1-Q3: 6-10) and 22 (Q1-Q3: 15-29), respectively. In those patients assigned to PCI, median RIcoro and RImyo values were 67% and 85%, respectively. Compared with the group assigned to optimal medical therapy alone, there was no difference in the likelihood of the primary outcome in those patients receiving complete anatomical or viability-guided revascularization (HR: 0.90; 95% CI: 0.62-1.32; and HR: 0.95; 95% CI: 0.66-1.35, respectively). A sensitivity analysis by residual SYNTAX score showed no association with outcome.

CONCLUSIONS

In patients with severe LV dysfunction, neither complete anatomical nor viability-guided revascularization was associated with improved event-free survival compared with incomplete revascularization or treatment with medical therapy alone. (Revascularization for Ischemic Ventricular Dysfunction) [REVIVED-BCIS2]; NCT01920048).

A Narrative Review of Revascularization in Chronic Coronary Syndrome/Disease: Concepts and Misconceptions

Ischemic heart disease represents a significant global burden of morbidity and mortality. While revascularization strategies are well defined in acute settings, there are uncertainties regarding chronic coronary artery disease treatment. Recent trials have raised doubts about the necessity of revascularization for "stable", chronic coronary syndromes or disease, leading to a shift towards a more conservative approach. However, the issue remains far from settled. In this narrative review, we offer a summary of the most pertinent evidence regarding revascularization for chronic coronary disease, while reflecting on less-often-discussed details of major clinical trials. The cumulative evidence available indicates that there can be a prognostic benefit from revascularization in chronic coronary syndrome patients, provided there is significant ischemia, as demonstrated by either imaging or coronary physiology. Trials that have effectively met this criterion consistently demonstrate a reduction in rates of spontaneous myocardial infarction, which holds both prognostic and clinical significance. The prognostic benefit of revascularization in patients with heart failure with reduced ejection fraction remains especially problematic, with a single contemporary trial favouring surgical revascularization. The very recent publication of a trial focused on revascularizing non-flow-limiting "vulnerable" plaques adds further complexity to the field. The ongoing debates surrounding revascularization in chronic coronary syndromes emphasize the importance of personalized strategies. Revascularization, added to the foundational pillar of medical therapy, should be considered, taking into account symptoms, patient preferences, coronary anatomy and physiology, ischemia tests and intra-coronary imaging.

Outcomes of Percutaneous Revascularization in Severe Ischemic Left Ventricular Dysfunction

PURPOSE OF REVIEW

This article presents a comprehensive review of coronary revascularization versus optimal medical therapy (OMT) in patients with severe ischemic left ventricular dysfunction.

RECENT FINDINGS

The REVIVED-BCIS2 trial randomized 700 patients with extensive coronary artery disease and left ventricular (LV) ejection fraction (LVEF) ≤ 35% and viability in more than four dysfunctional myocardial segments to percutaneous coronary intervention (PCI) plus OMT versus OMT alone. Over a median duration of 41 months, there was no difference in the composite of all-cause mortality, heart failure hospitalization, or improvement in LVEF with PCI plus OMT versus OMT alone at 6 and 12 months, quality of life scores at 24 months, or fatal ventricular arrhythmia. The STICH randomized trial was conducted between 2002 and 2007, involving patients with LV dysfunction and coronary artery disease. The patients were assigned to either CABG plus medical therapy or medical therapy alone. At the 5-year follow-up, the trial showed that CABG plus medical therapy reduced cardiovascular disease-related deaths and hospitalizations but no reduction in all-cause mortality. However, a 10-year follow-up showed a significant decrease in all-cause mortality with CABG. The currently available evidence showed no apparent benefit of PCI in severe ischemic cardiomyopathy as compared to OMT, but that CABG improves outcomes in this patient population. The paucity of data on the advantages of PCI in this patient population underscores the critical need for optimization of medical therapy for better survival and quality of life until further evidence from RCTs is available.

Selecting the appropriate patients for coronary artery bypass grafting in ischemic cardiomyopathy-importance of myocardial viability

Patients who undergo coronary artery bypass graft (CABG) surgery in ischemic cardiomyopathy have a survival advantage over medical therapy at 10 years. The survival advantage of CABG over medical therapy is due to its ability to reduce future myocardial infarction, and by conferring electrical stability. The presence of myocardial viability does not provide a differential survival advantage for CABG over medical therapy. Presence of angina and inducible ischemia are also less predictive of outcome. Moreover, CABG is associated with significant early mortality. Hence, careful patient selection is more important for reducing the early mortality and improving the long-term outcome than relying on results of myocardial viability. Younger patients with good exercise tolerance benefit the most, while patients who are frail and patients with renal dysfunction and dysfunctional right ventricle seem to have very high operative mortality. Elderly patients, because of poor life expectancy, do not benefit from CABG, but the age cutoff is not clear. Patients also need to have revascularizable targets, but this decision is often based on experience of the surgical team and heart team discussion. These recommendations are irrespective of the myocardial viability tests. Optimal medical treatment remains the cornerstone for management of ischemic cardiomyopathy.

Myocardial viability on trial

The concept of myocardial viability is usually referred to areas of the myocardium, which show contractile dysfunction at rest and in which contractility is expected to improve after revascularization. The traditional paradigm states that an improvement in function after revascularization leads to improved health outcomes and that assessment of myocardial viability in patients with ischaemic left ventricular dysfunction (ILVD) is a prerequisite for clinical decisions regarding treatment. A range of retrospective observational studies supported this 'viability hypothesis'. However, data from prospective trials have diverged from earlier retrospective studies and challenge this hypothesis. Traditional binary viability assessment may oversimplify ILVD's complexity and the nuances of revascularization benefits. A conceptual shift from the traditional paradigm centred on the assessment of viability as a dichotomous variable to a more comprehensive approach encompassing a thorough understanding of ILVD's complex pathophysiology and the salutary effect of revascularization in the prevention of myocardial infarction and ventricular arrhythmias is required.