Value of Cardiovascular Magnetic Resonance Imaging-Derived Baseline Left Ventricular Ejection Fraction and Volumes for Precise Risk Stratification of Patients With Ischemic Cardiomyopathy: Insights From the Surgical Treatment for Ischemic Heart Failure (STICH) Trial

Clinical and prognostic implications of left ventricular dilatation in heart failure

AIMS

To assess the agreement between left ventricular end-diastolic diameter index (LVEDDi) and volume index (LVEDVi) to define LV dilatation and to investigate the respective prognostic implications in patients with heart failure (HF).

METHODS AND RESULTS

Patients with HF symptoms and LV ejection fraction (LVEF) < 50% undergoing cardiac magnetic resonance were evaluated retrospectively. LV dilatation was defined as LVEDDi or LVEDVi above the upper normal limit according to published reference values. Patients were followed up for the combined endpoint of cardiovascular death or HF hospitalization during 5 years. A total of 564 patients (median age 64 years; 79% men) were included. LVEDDi had a modest correlation with LVEDVi (r = 0.682, P < 0.001). LV dilatation was noted in 84% of patients using LVEDVi-based definition and in 73% using LVEDDi-based definition, whereas 20% of patients displayed discordant definitions of LV dilatation. During a median follow-up of 2.8 years, patients with both dilated LVEDDi and LVEDVi had the highest cumulative event rate (HR 3.00, 95% CI 1.15-7.81, P = 0.024). Both LVEDDi and LVEDVi were independently associated with the primary outcome (hazard ratio 3.29, 95%, P < 0.001 and 2.8, P = 0.009; respectively).

CONCLUSION

The majority of patients with HF and LVEF < 50% present both increased LVEDDi and LVEDVi whereas 20% show discordant linear and volumetric definitions of LV dilatation. Patients with increased LVEDDi and LVEDVi have the worst clinical outcomes suggesting that the assessment of these two metrics is needed for better risk stratification.

Left ventricular volume change and long-term outcomes in ischaemic cardiomyopathy with or without surgical revascularisation: A post-hoc analysis of a randomised controlled trial

BACKGROUND

Whether the association between post-therapeutic left ventricular volume change and long-term outcomes in ischaemic cardiomyopathy is influenced by the performance of coronary artery bypass grafting (CABG) remains unclear. We sought to perform a post-hoc analysis of the Surgical Treatment of Ischaemic Heart Failure (STICH) trial to investigate this association in patients treated with medical therapy (MED) with or without CABG.

METHODS

From July 24, 2002, to May 5, 2007, 1212 patients with ischaemic cardiomyopathy were enrolled in the STICH trial (NCT00023595) from 99 sites in 22 countries, and were randomly assigned to undergo CABG plus MED or MED alone. We completed a post-hoc analysis of this trial. Patients with paired left ventricular end-systolic volume index (ESVI) measured at baseline and 4-months were included in our analysis. The association between change in ESVI from baseline to 4-months and cardiovascular mortality or all-cause mortality was assessed in MED arm and CABG plus MED arm.

FINDINGS

523 patients were included, with 291 (55.6%) assigned to MED arm and 232 (44.4%) to CABG plus MED arm. At a 4-month follow-up, ESVI reduction was more likely to occur among patients undergoing CABG plus MED. After a median follow-up of 10.3 years, for each 26% (1- standard deviation) decrement in ESVI, it was associated with a 22% lower risk of cardiovascular mortality (HR 0.78; 95% CI, 0.65-0.94) and 19% lower risk of all-cause mortality (HR 0.81; 95% CI, 0.69-0.95) in MED arm, whereas this association was not shown in CABG plus MED arm (cardiovascular mortality: HR 0.90; 95%CI, 0.74-1.10; all-cause mortality: HR 0.93; 95%CI, 0.79-1.09). A 16% reduction in ESVI was determined to be the most appropriate threshold of change in ESVI in the MED arm.

INTERPRETATION

In patients with ischaemic cardiomyopathy, left ventricular volume change was associated with long-term prognosis after medical therapy alone, whereas was likely not an optimal benchmark for evaluating the survival benefits associated with CABG. A more than 16% reduction in ESVI might assist in therapeutic efficacy assessment and prognostic evaluation in medically treated patients.

FUNDING

National Natural Science Foundation of China; Natural Science Funds of Guangdong Province.

Outcomes of Coronary Artery Bypass Grafting in Patients With Poor Myocardial Viability: A Systematic Review and Meta-Analysis of the Last Decade

OBJECTIVES

Our objective is to assess whether the presence of myocardial viability is a predictor of mortality among patients undergoing coronary artery bypasss grafting (CABG) through a systematic review meta-analysis.

METHODS

Comprehensive review of EMBASE and PubMed in accordance with PRISMA guidelines, including studies of patients undergoing CABG with assessment of myocardial viability and recorded long-term mortality, age and sex. Studies were restricted to the last decade, and data were stratified by imaging modality (magnetic resonance imaging [MRI] or nuclear medicine). Random-effects model for assessing pooled effect, heterogeneity assessment using Chi-square and I² statistics, publication bias assessed by funnel plots and Egger's test.

RESULTS

Meta-analysis of contemporary data (January 2010 to October 2020) yielded 3,621 manuscripts of which 92 were relevant, and 6 appropriate for inclusion with 993 patients. Pooled analysis showed that patients with non-viable myocardium undergoing CABG are at 1.34 times the risk of mortality compared to those with viable myocardium (95% CI 1.01-1.79, p=0.05). Subgroup analysis of the MRI or nuclear medicine modalities was not statistically significant and there was no confounding by age or sex in meta-regression. There was significant heterogeneity in imaging modality and diagnostic criteria, but heterogeneity between study findings was low with an I² statistic of 29%. The risk of publication bias was moderate on the Newcastle-Ottawa Scale), but not statistically significant (Egger's Test coefficient=1.3, 95%CI -0.35-2.61, p=0.10).

CONCLUSIONS

There is a multitude of methods for assessing cardiac viability for coronary revascularisation surgery, making meta-analyses fraught with limitations. Our meta-analysis demonstrates that the finding of non-viable myocardium can not be used draw conclusions for risk assessment in coronary surgery.

CD14, CD163, and CCR1 are involved in heart and blood communication in ischemic cardiac diseases

Objective

Cardiac diseases lead to heart failure (HF), but the progression can take several years. Using blood samples to monitor changes in the heart before clinical symptoms begin may help to improve patient management.

Methods

Microarray data GSE42955 and GSE9128 were used as study datasets and GSE16499, GSE57338, and GSE59867 were used as validation groups. The “limma” package from R Language was used to identify differentially expressed genes. Functional enrichment analyses of gene ontology terms and Kyoto Encyclopedia of Genes and Genomes pathways were performed using Database for Annotation, Visualization and Integrated Discovery. We also investigated the correlation between the heart and blood using the mRNA expression level.

Results

Three hub genes, CD14, CD163, and CCR1, were identified. Functional enrichment analyses showed their involvement in the immune response and in the inflammatory response, which are the critical biochemical processes in ischemic HF. The mRNA expression level further demonstrated that a special model may exist to help to predict the mRNA level in the heart based on that in blood.

Conclusions

Our study identified three biomarkers that can connect the heart and blood in ischemic heart diseases, which may be a new approach to help better manage ischemic cardiac disease patients.