Left ventricular function outcome after coronary artery bypass grafting, King Abdullah Medical City (KAMC)- single-center experience

[Amélioration précoce de la fraction d'éjection chez les patients ayant une fraction d'éjection réduite après un pontage coronarien]

BACKGROUND

Despite advancements in surgical technique, myocardial shield, and postoperative care, Coronary artery bypass grafting (CABG) among patients with reduced ejection fraction (EF) remains a surgical challenge due to their greater postoperative morbidity and mortality. This study aims to determine the early outcome of patients with reduced LVEF undergoing CABG and the improvement in the ejection fraction after revascularization.

METHODS

A total of 62 patients with impaired Left Ventricular (LV) systolic function (LVEF = 35-40 %) who underwent isolated On-pump CABG at the Department of Cardiothoracic Surgery in Assiut University Hospitals and who had met the listed inclusion and exclusion criteria were eligible for the study. Different variables (preoperative, intraoperative, and postoperative) were collected, studied, and compared.

RESULTS

The mean age of the patients was 57.81 ± 7.57 years, 66.1 % were male and 33.9 % were female. 44 (71.0%) patients were administered antegrade cardioplegia, whereas 18 (29.0%) patients were administered antegrade plus retrograde cardioplegia. Mean LVEF increased significantly from 37.97 ± 1.38% before surgery to 51.87 ± 3.54% after surgery (P ˂ 0.05). Post-operative low cardiac output syndrome occurred in 37 (59.7 %) of patients, pulmonary complications in 15 (24.2%), neurological complications in 10 (16.1%), sternal wound infection in 9 (14.5%), atrial fibrillation in 5 (8.1%) and acute kidney injury in 5 (8.1 %) of patients. In-hospital mortality was 16.1% (10 patients).

CONCLUSION

Based on the findings, CABG in patients with reduced preoperative LVEF improves the postoperative LVEF and NYHA functional class.

Outcomes of coronary artery bypass grafting based on myocardial perfusion imaging

Introduction

Coronary artery disease (CAD) is the foremost single cause of mortality and loss of disability-adjusted life years globally and a large percentage of this burden is found in low and middle income countries, with the treatment strategies based on revascularisation, based on studies that have shown that on revascularisation of viable myocardium there is an improvement of function over a period of time.

Aim

To evaluate the utilization of myocardial perfusion imaging (MPI) for identifying viable myocardium and assessing the improvement.

Material and methods

This prospective observational study was conducted in patients having CAD planned for coronary artery bypass grafting. The patients were evaluated using 2D ECHO and MPI preoperatively and postoperatively after 1 year.

Results

Mean ejection fraction preoperatively was 40.6 ±9.72% and postoperatively it improved to 41.32 ±10.64% and ejection fraction was calculated using MPI and an average improvement from 35.98 ±12.72% to 45.51 ±12.61% (p ≤ 0.0001). Summed rest score was calculated and an improvement was noted from 24.28 ±8.47 to 18.02 ±8.75 (p ≤ 0.0001). Total perfusion deficit was calculated and was found to have reduced from 32.44 ±11.98 to 25.61 ±12.23 (p ≤ 0.0001).

Conclusions

MPI was able to accurately assess the improvement, which correlated not only with the 2D echocardiography data but also with the clinical wellbeing of the patients. Being a non-invasive, quick procedure, it should be added to the arsenal of the cardiac surgeon for evaluation of patients with diffuse diseases, low ejection fractions, patients who might generally be considered inoperable.

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.

The Effect of Low Preoperative Ejection Fraction on Mortality After Cardiac Surgery in Indonesia

Background

Among cardiac surgery patients, low preoperative left ventricular ejection fraction (LVEF) is common and has been associated with poor outcomes. The objective of this study was to assess the association between LVEF and postoperative mortality in patients undergoing open-heart surgery in several hospitals in Indonesia.

Methods

We conducted a multicenter study with the retrospective design using data from patients undergoing open-heart surgery in 4 institutions in Indonesia. Data regarding LVEF and other potential risk factors were extracted from medical records and compiled in one datasheet. Statistical analyses were performed to assess if low LVEF was associated with postoperative mortality and identify other potential risk factors.

Results

A total of 4789 patients underwent cardiac surgery in participating centers during the study period. Of these, 189 subjects (3.9%) had poor preoperative LVEF. Poor LVEF was associated with postoperative mortality (adjusted OR 2.761, 95% CI 1.763–4.323, p < 0.001). Based on types of surgery, LVEF had a significant association with mortality only in CABG patients, while there was no such association in valve surgery and inconclusive in congenital surgery patients. Other significant independent predictors of in-hospital mortality included age more than 65 years old, non-elective surgery, the complexity of procedures, history of cardiac surgery, organ failure, CARE score ≥ 3, NYHA class ≥ III, and poor right ventricular function.

Conclusion

Patients with low preoperative LVEF undergoing open-heart surgery had a higher risk of postoperative mortality. Cardiac surgery can be performed with acceptable mortality rates. Accurate selection of patients, risk/benefit evaluation, and planning of surgical and anesthesiological management are mandatory to improve outcomes.

Significance of preoperative left ventricular ejection fraction in 5-year outcome after isolated CABG

BACKGROUND

Pre-operative ejection fraction (EF) and comorbidities affect post-op outcomes. We aimed to compare the mortality and adverse events of patients with different baseline EF and also to evaluate the distribution of comorbidities in each EF group.

METHODS

A total of 20,937 patients who underwent isolated coronary artery bypass graft (CABG) surgery from January 2006 to December 2016 was included. Patients were divided into three groups based on their pre-operative left ventricular EF as follows; (1) Normal: EF ≥ 50%; (2) Mild to moderately reduced: 50% < EF ≤ 35%; and (3) Severely reduced: EF < 35%. The backward elimination method was considered for multivariate Cox-regression analysis to locate predictors of mortality and non-fatal cerebro-cardiovascular events (CCVEs). The median follow-up time was 5.61 [3.12-8.0] years.

RESULTS

The mean age in the total population was 60.94 ± 9.51 years and 73.6% of the total population was male. Diabetes mellitus was the common risk factor of mortality and CCVE in all EF groups. Impaired renal function (GFR < 60 ml/min) was associated with a higher risk of mortality after CABG regardless of EF level. The median 5-year mortality rate in patients with normal EF, mild-moderately reduced EF and severely reduced EF were 9.5%, 12.8%, and 22.7% respectively (P < 0.001). Although the trend of CCVEs was higher in severe left ventricle (LV) dysfunction, it was not statistically significant (p = 0.071).

CONCLUSION

Patients with severely reduced EF are at higher risk of mortality after CABG compared to those with higher EF levels; however, the rate of CCVEs may not be necessarily higher after adjustment for multiple pre-operative comorbidities.