Predicting outcomes in patients with low ejection fraction undergoing coronary artery bypass graft.

Introduction: Reduced left ventricular ejection fraction (LVEF) is a well-known predictor of adverse events after cardiac surgery. We aimed to assess the outcomes in patients with low LVEF undergoing coronary artery bypass graft. Methods: In this retrospective cohort, we included all patients with left ventricular ejection fraction ≤ 40 who underwent coronary artery bypass grafting between March 2007 and March 2016 (with a median follow-up of nine years) at Tehran Heart Center. Demographics and clinical characteristics were extracted from the data registry. Akaike information criterion (AIC) was used. The univariate Cox regression was performed. We investigated the predictors of mortality and major adverse cardiac and cerebrovascular events (MACCE) using Cox multivariable regression. Results: In total, 5,532 cases (79 % male) with a mean age of 65.58 were included in the study. The nine-year overall survival was calculated at 68 %, and more than half of the patients had MACCE (55 %). In adjusted multivariable Cox regression analysis, moderate to severe mitral valve regurgitation, glomerular filtration rate ≤ 60, mild right ventricular dysfunction, and valvular heart disease independently predicted higher mortality. The abovementioned predictors and peripheral vascular disease significantly increased MACCE. Conclusion: Our study indicates the clinical significance of mitral regurgitation, valvular heart disease, and renal function in patients with low ejection fraction treated by coronary artery bypass grafting surgery. Identifying predictors of adverse events can help with clinical decision-making and risk stratification, ultimately improving patient outcomes.

Sex-based association between high-density lipoprotein cholesterol and adverse outcomes after coronary artery bypass grafting.

BACKGROUND: High-density lipoprotein cholesterol (HDL-C) is shown to be an independent protective factor against coronary artery diseases (CAD). Yet there are limited studies focusing on the association between HDL-C and coronary artery bypass graft (CABG) surgery outcomes. HYPOTHESIS: Low levels of HDL-C are associated with higher incidence of adverse outcomes in patients undergoing CABG. METHODS: This registry-based study included 17,772 patients who underwent elective isolated CABG between 2007 and 2017. Patients were classified into low and desirable HDL-C groups based on their serum HDL-C levels at admission and were followed for one-year post-surgery. The study population included 13,321 patients with low HDL-C and 4,451 with desirable HDL-C. proportional hazard Cox models were performed to evaluate the association between HDL-C levels and incidence of mortality as well as major adverse cardiovascular and cerebrovascular events (MACCE), while adjusting for potential confounders. Moreover, participants were stratified based on sex and the association was also investigated in each subgroup separately. RESULTS: No significant difference was found between the groups regarding incidence of both mortality and MACCE, after adjusting with Inverse Probability Weighting (IPW) [HR (95%CI): 0.84 (0.46-1.53), p-value:0.575 and HR (95% CI): 0.91 (0.56-1.50), p-value:0.733, respectively]. According to the sex-based subgroup analysis, no significant association was observed after adjustment with IPW analysis. However, as we examined the association between the interaction of HDL-C levels, sex and cardiovascular outcomes, we found a significant association (HR;1.19 (95%CI: 1.04-1.45); p = 0.030). CONCLUSION: HDL-C level was not associated with either mortality or MACCE during one year after CABG procedure. Sex-based analysis showed that in males, HDL-C is significantly more protective against these outcomes, compared to females. Further studies are necessary to elucidate the exact mechanisms mediating such association.

Factors Affecting Late Atrial Fibrillation and Its Association With Coronary Artery Bypass Outcomes.

BACKGROUND: Although predictors and outcomes of postoperative atrial fibrillation (POAF) are well studied, evidence is lacking concerning postdischarge late/recurrent atrial fibrillation (AF). This study evaluated factors affecting late/recurrent AF and its association with coronary artery bypass grafting (CABG) outcomes in a real-world setting. METHODS: From 2012 through 2016, 5175 patients were included. Independent factors associated with late/recurrent AF were identified in a competing risk setting. Cox proportional hazard regression was used to evaluate the association between late/recurrent AF and study outcomes, consisting of all-cause mortality, major adverse cardio-cerebrovascular events, acute coronary syndrome, cerebrovascular events, and heart failure admissions. RESULTS: During a median follow-up of 60 months (quartile 1-quartile 3, 59.3-60.7 months), late/recurrent AF developed in 85 patients (1.64%). Independent factors associated with late/recurrent AF were age (subdistribution hazard ratio [sHR], 1.04; 95% CI, 1.02-1.07), left-ventricular ejection fraction (sHR, 0.97; 95% CI, 0.95-0.99), length of stay (sHR, 1.02; 95% CI, 1.01-1.04), and POAF (sHR, 4.02; 95% CI, 2.50-6.45). Late/recurrent AF was not significantly associated with all-cause mortality and major adverse cardio-cerebrovascular events at unadjusted or adjusted levels (adjusted hazard ratio, 0.80 [95% CI, 0.50-1.28] and 0.74 [95% CI, 0.48-1.13], respectively). Nevertheless, it significantly increased the unadjusted risk of cerebrovascular events (hazard ratio, 2.28; 95% CI, 01.07-4.87), which disappeared after adjustments. CONCLUSIONS: Patients with advanced age, a lower left-ventricular ejection fraction, and POAF are more likely to have late/recurrent clinical AF. Albeit counterintuitive, late/recurrent AF was not independently associated with worse midterm post-CABG outcomes. These observations need to be further elucidated in larger-scale studies and interpreted in the context of a developing country with limited resources for late AF surveillance.

The prognostic role of the low and very low baseline LDL-C level in outcomes of patients with cardiac revascularization; comparative registry-based cohort design.

BACKGROUND: Although low-density lipoprotein-cholesterol (LDL-C) level is considered one of the main prognostic factors in patients with coronary artery bypass grafting (CABG), the question about "the lower the better" is still unanswered. We aimed to evaluate and compare the outcomes of patients with CABG and low or very low baseline LDL-C, regardless of statin usage. METHODS: In this registry-based cohort study, 10,218 patients with low/very low (70-100 and ≤ 70 mg/dL) baseline LDL-C who underwent isolated and the first-time CABG without known previous history of cardio-cerebrovascular events, were included and compared. The median follow-up was 73.33 (72.15-74.51) months. Primary outcomes were all-cause mortality and major adverse cardio-cerebrovascular events (MACCE) (consisted of all-cause mortality, acute coronary syndrome, stroke or transient ischemic attack, and the need for repeat revascularization [percutaneous coronary intervention or redo-CABG]). Cox regression analyses before and after the propensity score matching (PSM) model were applied to evaluate and compare outcomes. RESULTS: The mean age of the study population was 66.17 ± 9.98 years old and 2506 (24.5%) were women. Diabetes mellitus and a history of cigarette smoking were significantly higher in the very low LDL group (P-value ≤ 0.001). In Cox regression analyses before applying PSM model, both all-cause mortality (14.2% vs. 11.9%, P-value = 0.004 and MACCE (26.0% vs. 23.6%, P-value = 0.006) were significantly higher in the very low LDL group compared to low LDL. However, these results were no longer significant after applying the PSM model (all-cause mortality HR: 1.115 [95% CI: 0.986-1.262], P = 0.083 and MACCE HR: 1.077 [95%CI: 0.984-1.177], P = 0.095). The sensitivity analysis to remove the statin effect demonstrated that very low LDL-C level was correlated to higher risk of all-cause mortality in both unmatched and PSM analyses. CONCLUSION: Very low serum LDL-C levels (≤ 70 mg/dl) could increase long-term all-cause mortality and cardiovascular events in patients who have undergone isolated CABG.

7-year outcomes in diabetic patients after coronary artery bypass graft in a developing country.

BACKGROUND: Revascularization in diabetic patients with coronary artery disease remains a challenge in cardiology practice. Although clinical trials have reported the mid-term superiority of coronary artery bypass grafting (CABG) surgery over percutaneous coronary intervention in these patients, little is known about the long-term outcomes of CABG in diabetic patients compared to non-diabetics, particularly in developing countries. METHODS: Between 2007 and 2016, we recruited all patients who underwent isolated CABG in a tertiary care cardiovascular center in a developing country. The patients were followed at 3-6 months and 12 months after surgery, and then annually. The study endpoints were 7-year all-cause mortality and major adverse cardiac and cerebrovascular events (MACCE). RESULTS: Of 23,873 patients (17,529 males, mean age 65.67 years) who underwent CABG, 9227 (38.65%) patients were diagnosed with diabetes. After adjustment for potential confounders, patients with diabetes experienced a 31% increase in MACCE seven years after surgery compared to the non-diabetic patients (HR = 1.31, 95% CI: 1.25-1.38, P-value < 0.0001). Meanwhile, diabetes contributes to a 52% increase in the risk of all-cause mortality after CABG (HR = 1.52, 95% CI: 1.42-1.61, P-value < 0.0001). CONCLUSIONS: Our study showed a higher risk of all-cause mortality and MACCE at seven years in diabetic patients undergoing isolated CABG. The outcomes in the studied center in a developing country were comparable to western centers. The high incidence of adverse outcomes in the long term in diabetic patients implies that not only short-term but long-term measures should be taken to improve the CABG outcomes in this challenging patient population.

Opium consumption and long-term outcomes of CABG surgery in patients without modifiable risk factors.

Background: The question about the significance of opium consumption as a coronary artery disease (CAD) risk factor still remains open. The present study aimed to evaluate the association between opium consumption and long term outcomes of coronary artery bypass grafting (CABG) in patients without standard modifiable CAD risk factors (SMuRFs; hypertension, diabetes, dyslipidemia, and smoking). Methods: In this registry-based design, we included 23,688 patients with CAD who underwent isolated CABG between January 2006 to December 2016. Outcomes were compared in two groups; with and without SMuRF. The main outcomes were all-cause mortality, fatal and nonfatal cerebrovascular events (MACCE). Inverse probability weighting (IPW) adjusted Cox's proportional hazards (PH) model was used to evaluate the effect of opium on post-op outcomes. Results: During 133,593 person-years of follow-up, opium consumption was associated with increased risk of mortality in both patients with and without SMuRFs (weighted Hazard Ratio (HR)s: 1.248 [1.009, 1.574] and 1.410 [1.008, 2.038], respectively). There was no association between opium consumption and fatal and non-fatal MACCE in patients without SMuRF (HR = 1.027 [0.762-1.383], HR 0.700 [0.438-1.118]). Opium consumption was associated with earlier age of CABG in both groups; 2.77 (1.68, 3.85) years in SMuRF-less and 1.70 (1.11, 2.38) years in patients with SMuRFs. Conclusion: Opium users not only undergo CABG at younger ages but also have a higher rate of mortality regardless of the presence of traditional CAD risk factors. Conversely, the risk of MACCE is only higher in patients with at least one modifiable CAD risk factor.

Mortality across the spectrum of hemoglobin level in patients undergoing surgical coronary revascularization.

BACKGROUND: Preoperative hemoglobin (Hb) level is a predictor of in-hospital and midterm mortality in patients undergoing coronary artery bypass grafting surgery (CABG). However, the debate about the different hazards across Hb levels and sex differences in outcome occurrence is still on the table. METHODS: This is a registry-based serial cross-sectional study at Tehran Heart Center. Nonanemic patients who underwent CABG with complete follow-up data were included. The Restricted Cubic Splines (RCS) in the Cox model was used to calculate the sex-specific correlation between in-hospital, 6-month, and 1-year mortalities and normal Hb levels using odds ratio for the in-hospital and hazard ratios for 6-month and 1-year mortality, adjusted for all possible confounders. RESULTS: From 2005 to 2016, a total of 13,557 patients were included, of which 134 had in-hospital mortality as our primary outcome. Preoperative Hb levels were significantly lower in the deceased. Moreover, dead patients had significantly higher rates of diabetes and hypertension, while lower ejection fraction. Cut-offs for reference Hb level were higher for males compared with females. The correlation between Hb level and in-hospital mortality was nearly U-shaped. Quantitatively, Hb of ≥15.62 and ≤13.25 g/dL for men and that of ≥14.92 and ≤13.4 g/dL for women tended to be associated with higher in-hospital mortality. CONCLUSIONS: The association between preoperative Hb level and in-hospital mortality differs in men and women and does not follow a linear correlation among nonanemic patients. Both low and high numbers in the Hb level spectrum are at greater risk.

Machine learning-based prediction of 1-year mortality in hypertensive patients undergoing coronary revascularization surgery.

BACKGROUND: Machine learning (ML) has shown promising results in all fields of medicine, including preventive cardiology. Hypertensive patients are at higher risk of mortality after coronary artery bypass graft (CABG) surgery; thus, we aimed to design and evaluate five ML models to predict 1-year mortality among hypertensive patients who underwent CABG. HYOTHESIS: ML algorithms can significantly improve mortality prediction after CABG. METHODS: Tehran Heart Center's CABG data registry was used to extract several baseline and peri-procedural characteristics and mortality data. The best features were chosen using random forest (RF) feature selection algorithm. Five ML models were developed to predict 1-year mortality: logistic regression (LR), RF, artificial neural network (ANN), extreme gradient boosting (XGB), and naïve Bayes (NB). The area under the curve (AUC), sensitivity, and specificity were used to evaluate the models. RESULTS: Among the 8,493 hypertensive patients who underwent CABG (mean age of 68.27 ± 9.27 years), 303 died in the first year. Eleven features were selected as the best predictors, among which total ventilation hours and ejection fraction were the leading ones. LR showed the best prediction ability with an AUC of 0.82, while the least AUC was for the NB model (0.79). Among the subgroups, the highest AUC for LR model was for two age range groups (50-59 and 80-89 years), overweight, diabetic, and smoker subgroups of hypertensive patients. CONCLUSIONS: All ML models had excellent performance in predicting 1-year mortality among CABG hypertension patients, while LR was the best regarding AUC. These models can help clinicians assess the risk of mortality in specific subgroups at higher risk (such as hypertensive ones).

BMI modifies HDL-C effects on coronary artery bypass grafting outcomes.

BACKGROUND: Despite the recognized implications of high-density lipoprotein cholesterol (HDL-C) in cardiovascular diseases, the role of body mass index (BMI) in HDL-C association with cardiovascular outcomes remains unclear. This study investigated the possible modifying implications of BMI on the correlation between HDL-C and coronary artery bypass grafting (CABG) outcomes. METHODS: The present cohort included isolated CABG patients (median follow-up: 76.58 [75.79-77.38] months). The participants were classified into three groups: 18.5 ≤ BMI < 25 (normal), 25 ≤ BMI < 30 (overweight), and 30 ≤ BMI < 35 (obese) kg/m2. Cox proportional hazard models (CPHs) and restricted cubic splines (RCSs) were applied to evaluate the relationship between HDL-C and all-cause mortality as well as major adverse cardio-cerebrovascular events (MACCEs) in different BMI categories. RESULTS: This study enrolled a total of 15,639 patients. Considering the final Cox analysis among the normal and overweight groups, HDL-C ≥ 60 was a significant protective factor compared to 40 < HDL-C < 60 for all-cause mortality (adjusted hazard ratio (aHR): 0.47, P: 0.027; and aHR: 0.64, P: 0.007, respectively). However, the protective effect of HDL-C ≥ 60 was no longer observed among patients with 30 ≤ BMI < 35 (aHR: 1.16, P = 0.668). RCS trend analyses recapitulated these findings; among 30 ≤ BMI < 35, no uniform inverse linear association was observed; after approximately HDL-C≈55, its increase was no longer associated with reduced mortality risk. RCS analyses on MACCE revealed a plateau effect followed by a modest rise in overweight and obese patients from HDL-C = 40 onward (nonlinear association). CONCLUSIONS: Very high HDL-C (≥ 60 mg/dL) was not related to better outcomes among obese CABG patients. Furthermore, HDL-C was related to the post-CABG outcomes in a nonlinear manner, and the magnitude of its effects also differed across BMI subgroups.

Off-pump versus on-pump coronary artery bypass graft surgery outcomes in patients with severe left ventricle dysfunction: inverse probability weighted study.

OBJECTIVE: In this study we aimed to compare on-pump and off-pump coronary artery bypass grafting (CABG) outcomes in patients presented with low left ventricular ejection fraction (EF) as a high-risk group of patients. METHODS: In this registry-based study from 2014 and 2016, all patients with severe left ventricular dysfunction (EF less than 35%) were included and followed until 2020. The median follow-up period was 47.83 [38.41, 55.19] months. Off pump CABG (OPCABG) was compared with on-pump CABG (ONCABG) in terms of mid-term non-fatal cardiovascular events (CVEs) and all-cause mortality. Propensity score method (with inverse probability weighting technique) was used to compare these two groups. RESULTS: From 14,237 patients who underwent isolated CABG, 2055 patients with EF ≤ 35% were included; 1705 in ONCABG and 350 patients in OPCABG groups. Although OPCABG was associated with lower risk of 30-days mortality (Odds Ratio [OR]: 0.021; Confidence Interval [CI] 95% [0.01, 0.05], P < 0.001); there was no significant difference between OPCABG and ONCABG in term of mid-term mortality and non-fatal CVEs ((Hazard ratio [HR]: 0.822; 95%CI [0.605, 1.112], p = 0.208) and (HR: 1.246; 95%CI [0.805, 1.929], p = 0.324), respectively). Patients with more than three traditional coronary artery disease risk factors, had more favorable outcomes (in terms of mid-term mortality) if underwent OPCABG (HR: 0.420; 95%CI [0.178, 0.992], p = 0.048). CONCLUSION: OPCABG was associated with lower risk of 30-days mortality; however, mid-term outcomes were comparable in both OPCABG and ONCABG techniques.

The association between different body mass index levels and midterm surgical revascularization outcomes.

BACKGROUND: There are conflicting results regarding the relationship between overweight/obesity and the outcomes of coronary artery bypass graft surgery (CABG), termed "the obesity paradox". This study aimed to evaluate the effects of body mass index (BMI) on the midterm outcomes of CABG. METHODS: This historical cohort study included all patients who underwent isolated CABG at our center between 2007 and 2016. The patients were divided into five categories based on their preoperative BMIs (kg/m2): 18.5≤BMI<25, 25≤BMI<30, 30≤BMI<35, 35≤BMI<40, and BMI≥40. Patients with BMIs below 18.5 kg/m2 were excluded. The endpoints of this study were all-cause mortality and major adverse cardio-cerebrovascular events (MACCEs), comprising acute coronary syndromes, cerebrovascular accidents, and all-cause mortality at five years. For the assessment of the linearity of the relationship between continuous BMI and the outcomes, plots for time varying hazard ratio of BMI with outcomes were provided. RESULTS: Of 17 751 patients (BMI = 27.30 ±4.17 kg/m2) who underwent isolated CABG at our center, 17 602 patients (mean age = 61.16±9.47 y, 75.4% male) were included in this study. Multivariable analysis demonstrated that patients with pre-obesity and normal weight had similar outcomes, whereas patients with preoperative BMIs exceeding 30 kg/m2 kg/m2 had a significantly higher risk of 5-year all-cause mortality and 5-year MACCEs than those with pre-obesity. Additionally, a positive association existed between obesity degree and all-cause mortality and MACCEs. Further, BMIs of 40 kg/m2 or higher showed a trend toward higher MACCE risks (adjusted hazard ratio, 1.32; 95% confidence interval, 0.89 to 1.95), possibly due to the small sample size. A nonlinear, albeit negligible, association was also found between continuous BMI and the study endpoints. CONCLUSIONS: Our findings suggest that preoperative obesity (BMI>30 kg/m2) in patients who survive early after CABG is associated with an increased risk of 5-year all-cause mortality and 5-year MACCEs. These findings indicate that physicians and cardiac surgeons should encourage patients with high BMIs to reduce weight for risk modification.

Effect of postoperative atrial fibrillation on early and mid-term outcomes of coronary artery bypass graft surgery.

OBJECTIVES: The long-term prognostic role of postoperative atrial fibrillation (POAF) in cardiovascular outcomes in patients undergoing cardiac surgery is uncertain. Our goal was to investigate the impact of new-onset POAF on midterm adverse cardiovascular events after coronary artery bypass graft (CABG) surgery. METHODS: We performed a retrospective cohort study of patients who underwent isolated CABG without a preoperative history of atrial fibrillation/flutter. POAF was defined as episodes of AF lasting ≥30 s during the hospitalization period. The effect of POAF on midterm all-cause mortality and cerebrovascular accidents/transient ischaemic attacks (CVA/TIA) was assessed using a Cox proportional hazard regression model in a competing risk setting. Additional analyses were performed on patients surviving an event-free early postoperative period (i.e. within 30 postoperative days after the index operation). RESULTS: A total of 9,310 patients were followed for a median duration of 48.7 months. New-onset POAF was associated with an increased risk of midterm all-cause mortality (HR = 1.648, 95% confidence interval: 1.402-1.937; P < 0.001) and CVA/TIA (subdistribution-HR = 1.635, 1.233-2.167; P = 0.001). After excluding patients who died during the early postoperative period, POAF remained significantly associated with higher late all-cause mortality (HR = 1.518, 1.273-1.811; P < 0.001). However, the risk of late CVA/TIA in patients who survived the early postoperative period without having a stroke was similar between those with and without POAF (subdistribution-HR = 1.174, 0.797-1.729; P = 0.418). CONCLUSIONS: New-onset POAF after CABG is associated with an increased risk of midterm overall mortality and stroke. However, late stroke risk is likely similar between patients with and without POAF who survive an event-free early postoperative period.

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.

Sex and age difference in risk factor distribution, trend, and long-term outcome of patients undergoing isolated coronary artery bypass graft surgery.

BACKGROUND: Preoperative coronary artery disease risk factors (CADRFs) distribution and pattern may also have an important role in determining major adverse cardiovascular events (MACEs). In this study, we aimed to evaluate the CADRFs distribution and trend over 10 years and also the long-term outcome of CABG in different age-sex categories. METHOD: In this registry-based serial cross-sectional study, we enrolled 24,328 patients who underwent isolated CABG and evaluated the prevalence of CADRFs according to sex and age. We used inverse probability weighting (IPW) to compare survival and MACE between the sexes. We also used Cox regression to determine each CADRFs effect on survival and MACEs. RESULTS: In general, DLP (56.00%), HTN (53.10%), DM (38.40%), and positive family history (38.30%) were the most frequent risk factors in all patients. Prevalence of HTN, DLP, DM, obesity, and positive family history were all higher in women, all statistically significant. The median follow-up duration was 78.1 months (76.31-79.87 months). After inverse probability weighting (to balance risk factors and comorbidities), men had lower MACEs during follow-up (HR 0.72; 95% CI 0.57-0.91; P value 0.006) and there was no significant difference in survival between sexes. DM and HTN were associated with higher mortality and MACEs in both sexes. CONCLUSION: Although DLP is still the most frequent CADRF among the CABG population, the level of LDL and TG is decreasing. Women experience higher MACE post CABG. Therefore, health care providers and legislators must pay greater attention to female population CADRFs and ways to prevent them at different levels.

Iatrogenic left circumflex coronary occlusion following mitral valve replacement surgery: A case report.

Injury to epicardial coronary arteries following mitral valve replacement surgery, albeit rare, could have fatal complications. In this case, we suggest conservative medical treatment as a safe approach in patients who are not suitable to undergo revascularization.

Effect of persistent opium consumption after surgery on the long-term outcomes of surgical revascularisation.

BACKGROUND: A wrong traditional belief persists among people that opium consumption beneficially affects cardiovascular disease and its risk factors. However, no evidence exists regarding the effect of opium consumption or cessation on the long-term risk of major adverse cardio-cerebrovascular events after coronary artery bypass grafting. We therefore aimed to evaluate the effect of persistent opium consumption after surgery on the long-term outcomes of coronary artery bypass grafting. METHODS: The study population consisted of 28,691 patients (20,924 men, mean age 60.9 years), who underwent coronary artery bypass grafting between 2007 and 2016 at our centre. The patients were stratified into three groups according to the status of opium consumption: never opium consumers (n = 23,619), persistent postoperative opium consumers (n = 3636) and enduring postoperative opium withdrawal (n = 1436). Study endpoints were 5-year mortality and 5-year major adverse cardio-cerebrovascular events, comprising all-cause mortality, acute coronary syndrome, cerebrovascular accident and revascularisation. RESULTS: After surgery, 3636 patients continued opium consumption, while 1436 patients persistently avoided opium use. The multivariable survival analysis demonstrated that persistent post-coronary artery bypass grafting opium consumption increased 5-year mortality and 5-year major adverse cardio-cerebrovascular events by 28% (hazard ratio (HR) 1.28, 95% confidence interval (CI) 1.06-1.54; P = 0.009) and 25% (HR 1.25, 95% CI 1.13-1.40; P < 0.0001), respectively. It also increased the 5-year risk of acute coronary syndrome by 34% (sub-distribution HR 1.34, 95% CI 1.16-1.55; P < 0.0001). CONCLUSIONS: The present data suggest that persistent post-coronary artery bypass grafting opium consumption may significantly increase mortality, major adverse cardio-cerebrovascular events and acute coronary syndrome in the long term. Future studies are needed to confirm our findings.

Preoperative oral pentoxifylline in case of coronary artery bypass grafting with left ventricular dysfunction (ejection fraction equal to/less than 30%).

OBJECTIVE: Most coronary artery bypass grafts are done by applying cardiopulmonary bypass, which usually induces unwanted inflammatory reactions and impairs the outcomes. In order to minimize the perilous response of cardiopulmonary bypass, pentoxifylline was getting used orally. METHODS: In a prospective, placebo-controlled, randomized clinical trial, 178 coronary artery bypass graft candidates with ejection fraction lower/equal to 30%, divided into two equal groups (pentoxifylline and control), participated in the study. Pentoxifylline patients received 400 mg pentoxifylline 3 times a day for 3 days before operation. The outcomes were compared between groups using student's t-test, Mann-Whitney U-test, Pearson chi-square, or Fisher's exact test. RESULTS: Pentoxifylline administration did not significantly affect troponin-T (p=0.68), but it reduced tumor necrosis factor-α (p=0.01) and interleukin-6 (p=0.01). It improved left ventricular ejection fraction significantly (p=0.01). White blood cell and platelet counts, hemoglobin, and hematocrit were not influenced by pentoxifylline. The drug did not affect blood urea nitrogen and creatinine, occurrence of renal failure, cerebrovascular accidents, and in-hospital mortality rate. The need for an intra-aortic balloon pump, cardiopulmonary bypass, and aortic cross-clamp times were not affected, either. Pentoxifylline decreased the intensive care unit stay (p<0.001), ventilation time, 10.4 hours in the pentoxifylline group against 14.7 hours in the control group (p=0.01), and the requirement of inotropic agents (p=0.02) and blood transfusion (p=0.01). CONCLUSION: Pentoxifylline has more beneficial potencies in reducing adverse events after coronary artery bypass graft using cardiopulmonary bypass, than what are known.

Evaluation of different chemical agents on the germinative layer of sheep hydatid cyst after implantation to peritoneal cavity of BALB/c.

In spite of the use of protoscolocidal agents during hydatid cyst surgery, a notable rate of disease recurrence in postoperation patients is still observed. The question remains whether living protoscolices lead to recurrence or the recurrence is due to the remainder of the germinative layer in the peritoneal cavity. The aim of this study was in vivo evaluation of different chemical (protoscolicidal) solutions on the germinative layer of the hydatid cyst. The germinative layer of sheep hydatid cyst was separated under sterile condition, divided into 0.25-cm(2) parts, and exposed to 0.5% cetrimide, 0.5% silver nitrate, 20% hypertonic saline, 15% dextrose and 25% dextrose, and normal saline as negative control for 2 min. The exposed germinative layers were implanted into the peritoneal cavity of 90 Balb/C mice (15 mice in each group). After nine months, the peritoneum was evaluated macroscopically as well as microscopically for the presence of any hydatid cyst. No hydatid cyst was observed in the peritoneal cavity of the exposed mice. The role of the germinative layer for inducing hydatid cysts in mice is questionable. However, the present study showed that the germinative layer had no role in the induction of hydatid cyst in these laboratory animals.