Improvement of ejection fraction after coronary artery bypass grafting surgery in patients with impaired left ventricular function

The Effectiveness of Coronary Artery Bypass Grafting in Patients with Left Ventricular Dysfunction

INTRODUCTION

Coronary artery bypass grafting (CABG) in patients with left ventricular dysfunction (LVD) remains a surgical challenge and is still controversial. The aim of this study was to evaluate the effectiveness of CABG in patients with LVD.

METHODS

This retrospective study included a total of 160 consecutive patients (133 males, 27 females, mean age 62.1±10.12 years [range 37 to 86 years]) who had a left ventricular ejection fraction (LVEF) ≤ 45% determined by echocardiography and underwent elective isolated CABG between September 2013 and December 2018. Preoperative echocardiographic data, such as ejection fraction, left ventricular (LV) end-systolic diameter, and LV end-diastolic diameter, were collected and evaluated. Preoperatively, 85 (53.13%) patients were in New York Heart Association functional class III or IV and the mean LVEF was 38.65±5.72% (range 20 to 45).

RESULTS

The overall hospital mortality was 5% (eight patients). Late follow-up was obtained in 152 (90%) cases (median follow-up time was 56,5 [3-87] months postoperatively). During follow-up, mortality developed in 11.3% (16 patients). Mean LVEF increased significantly from 38.78±5.59% before surgery to 43.29±8.46% after surgery (P<0.01). Mean late survival, freedom from coronary reintervention, and congestive heart failure rates were 86.3±3.3%, 88.7±3.9%, and 89.4±3.1%, respectively.

CONCLUSION

In patients with LVD, CABG can be performed with low postoperative morbidity and mortality rates. Patients with LVD could benefit from coronary bypass surgery regarding postoperative LV systolic function and higher quality of life.

Myocardial Function Prediction After Coronary Artery Bypass Grafting Using MRI Radiomic Features and Machine Learning Algorithms

The main aim of the present study was to predict myocardial function improvement in cardiac MR (LGE-CMR) images in patients after coronary artery bypass grafting (CABG) using radiomics and machine learning algorithms. Altogether, 43 patients who had visible scars on short-axis LGE-CMR images and were candidates for CABG surgery were selected and enrolled in this study. MR imaging was performed preoperatively using a 1.5-T MRI scanner. All images were segmented by two expert radiologists (in consensus). Prior to extraction of radiomics features, all MR images were resampled to an isotropic voxel size of 1.8 × 1.8 × 1.8 mm³. Subsequently, intensities were quantized to 64 discretized gray levels and a total of 93 features were extracted. The applied algorithms included a smoothly clipped absolute deviation (SCAD)-penalized support vector machine (SVM) and the recursive partitioning (RP) algorithm as a robust classifier for binary classification in this high-dimensional and non-sparse data. All models were validated with repeated fivefold cross-validation and 10,000 bootstrapping resamples. Ten and seven features were selected with SCAD-penalized SVM and RP algorithm, respectively, for CABG responder/non-responder classification. Considering univariate analysis, the GLSZM gray-level non-uniformity-normalized feature achieved the best performance (AUC: 0.62, 95% CI: 0.53-0.76) with SCAD-penalized SVM. Regarding multivariable modeling, SCAD-penalized SVM obtained an AUC of 0.784 (95% CI: 0.64-0.92), whereas the RP algorithm achieved an AUC of 0.654 (95% CI: 0.50-0.82). In conclusion, different radiomics texture features alone or combined in multivariate analysis using machine learning algorithms provide prognostic information regarding myocardial function in patients after CABG.

Infrared Thermographic Imaging of Chest Wall Perfusion in Patients Undergoing Coronary Artery Bypass Grafting

Coronary artery disease represents a leading cause of death worldwide, to which the coronary artery bypass graft (CABG) is the main method of treatment in advanced multiple vessel disease. The use of the internal mammary artery (IMA) as a graft insures an improved long-term survival, but impairment of chest wall perfusion often leads to surgical site infection and increased morbidity and mortality. Infrared thermography (IRT) has established itself in the past decades as a non-invasive diagnostic technique. The applications vary from veterinary to human medicine and from head to toe. In this study we used IRT in 42 patients receiving CABG to determine the changes in skin surface temperature preoperatively, two hours, 24 h and 6 days after surgery. The results showed a significant and independent drop of surface temperature 2 h after surgery on the whole surface of the chest wall, as well as a further reduction on the left side after harvesting the IMA. The temperature returned to normal after 24 h and remained so after 6 days. The study has shown that IRT is sufficiently sensitive to demonstrate the known, subtle reduction in chest wall perfusion associated with IMA harvesting.

Ejection Fraction Recovery after Coronary Artery Bypass Grafting for Ischemic Cardiomyopathy

BACKGROUND

 Controversy exists about left ventricular systolic function recovery after coronary artery bypass grafting in patients with ischemic cardiomyopathy. The aim of this study is to evaluate the temporal evolvement of left ventricular systolic function after coronary artery bypass surgery in patients with ischemic cardiomyopathy.

PATIENTS AND METHODS

 A total of 50 patients with coronary artery disease and left ventricular ejection fraction (LVEF) ≤35% underwent isolated coronary artery bypass grafting in a single center in the period 2017 to 2019. We performed a retrospective analysis of the echocardiographic and clinical follow-up data at 3 months and 1 year postoperatively.

RESULTS

 Median LVEF preoperatively was 25% (20-33%), mean patient age was 66 ± 8.2 years, 33 (66%) patients were operated off-pump, and 22 (44%) procedures were non-elective. There was no in-hospital myocardial infarction, stroke, and repeat revascularization. Three (6%) patients underwent re-exploration for bleeding or tamponade. In-hospital mortality was 8% and 1-year mortality was 12%. At 1 year postoperatively, there was no repeat revascularization, no myocardial infarction, 1 (2.6%) patient had a transient ischemic attack, and 10 (20%) patients required an implantable defibrillator. There was a statistically significant median ejection fraction increase at 3 months (15% [5-22%], p < 0.0001) and 1 year (23% [13-25%], p < 0.0001) postoperatively, with an absolute increase ≥10% in 32 (74.4%) and 30 (78.9%) patients at 3 months and 1 year, respectively.

CONCLUSION

 Patients with ischemic cardiomyopathy undergoing coronary artery bypass surgery show continuous recovery of left ventricular systolic function in the first postoperative year.

Comparative Analysis of Web of Science and Pubmed Indexed Medical Journals Published in Former Yugoslav Countries

INTRODUCTION

The source of scientific information, methods for their evaluation, and methodology of their use are critical for serious scientific research and publishing of the scientific research results. Certain methodological principles should be inexcusably followed when designing clinical or observational research to avoid bias and presentation of results that do not reflect the truth about the phenomenon that is the object of the study.

AIM

The aim of this study was to compare the methodological quality of clinical trials and observational studies published in medical journals from ex-Yugoslav countries indexed in Web of Science (WoS) and Pubmed/MEDLINE.

METHODS

Clinical studies published in medical journals of ex-Yugoslav countries were retrieved from the WoS and Pubmed database, and the sample for analysis was randomly chosen from the retrieved publications. The rate of the most common errors in the design of clinical/observational studies was established by a careful reading of the sampled publications and their checking against predefined criteria.

RESULTS

Number and percent of the evaluated studies that failed to meet each of the methodological criteria tested, number of the evaluated criteria not satisfied per database and number of studies that satisfied more than 4 criteria were analyzed per database. When explanatory potential of journal impact factor, number of citations, time elapsed from publication and a database where a journal is referred were tested by linear regression in regard to the number of methodological criteria satisfied per study, the linear regression model was obtained by backward deletion method and achieved R2 adjusted of 0.166 (F=13.827, df1 = 2, df2 = 127, p=0.000). The methodological quality of studies was directly related to impact factor of the journals (B = 0.976, 95% confidence interval 0.539 - 1.413, p=0.000) and inversely with the database where a journal is referred (B =-0.444, 95% confidence interval-0.824 - -0.064, p = 0.022). Each additional unit of impact factor increased number of satisfied methodological criteria for about 1, while referring a journal only in WoS decreased number of satisfied criteria for 0.45 points in comparison with journals referred in both WoS and Pubmed/MEDLINE, and for 0.9 points in comparison to journals referred only in MEDLINE.

CONCLUSION

Methodological and scientometric quality of clinical studies published in medical journals from ex-Yugoslav region varies significantly, and the variations are higher in journals referenced only in WoS than in journals referenced in Pubmed/MEDLINE only, or in both Pubmed and Web of Science databases.

Combined transepicardial and transseptal implantation of autologous CD 133+ bone marrow cells during bypass grafting improves cardiac function in patients with low ejection fraction

OBJECTIVES

Autologous CD133+ bone marrow stem cells may improve cardiac function. This randomized, single-blind clinical trial inquired whether a combined transepicardial and transseptal implantation of CD133+ stem cells during coronary artery bypass grafting (CABG) improve cardiac function with ejection fraction (EF) changes as a primary endpoint in patients with low EF.

METHODS

Thirty patients with coronary heart disease and EF <35% were randomized to undergo CABG alone or CABG with transseptal and transepicardial implantation of CD133+. Cardiac function was evaluated using cardiac magnetic resonance imaging (MRI) before and 6 months after CABG.

RESULTS

Preoperative EF was lower in the intervention group (25.88% ± 5.66%) than in the control group (30.18% ± 3.85%; P = .04). The adverse event incidence was similar between both groups. At 6 months, EF changes were significantly higher (8.69% ± 9.49; P = .04) in the CD133+ group than in the CABG-only group. Compared to the control group, significant improvements were seen in the wall motion score index (P = .003) and scar size proportion (P = .047) in the CD133+ group. The quality of life (QOL), assessed by a 6-minute walking test, showed considerable improvement in the CD133+ group compared to that in the control group (P = .03). The Minnesota Living with Heart Failure Questionnaire (MLHFQ) scale did not show improvement in the intervention group (P = .09, vs control).

CONCLUSION

Combined transepicardial and transseptal autologous CD133+ BMC implantation during bypass grafting improved cardiac function in low EF coronary artery disease patients.

Meta-Analyses of Human Cell-Based Cardiac Regeneration Therapies: What Can Systematic Reviews Tell Us About Cell Therapies for Ischemic Heart Disease?

Controversies from basic science, discrepancies from clinical trials, and divergent results from meta-analyses have recently arisen in the field of cell therapies for cardiovascular repair and regeneration. Noticeably, there are almost as many systematic reviews and meta-analyses published as there are well-conducted clinical studies. But how do we disentangle the confusion they have raised? This article addresses why results obtained from systematic reviews and meta-analyses of human cell-based cardiac regeneration therapies are still valid to inform the design of future clinical trials. It also addresses how meta-analyses are not free from limitations and how important it is to assess the quality of the evidence and the quality of the systematic reviews and finally how stronger conclusions can be drawn when several pieces of evidence converge.