Changes in cardiac cells due to ticagrelor and enoxaparin in a rat ischemia/reperfusion model

OBJECTIVE

Studies on ischemia/reperfusion injury remain the focus of interest. Ticagrelor and enoxaparin, which are antiaggregant and anticoagulant drugs developed for use in many cardiovascular pathologies, are still included in many ischemia/reperfusion studies. Remarkably, their new protective effects, especially with regard to ticagrelor, continue to be reported in the current literature. The aim of this study was to evaluate the beneficial effects of ticagrelor and enoxaparin pretreatments on the rat heart with histological and immunohistochemical markers in an ischemia/reperfusion model.

METHODS

Wistar-albino rats (weighing 350-400 g) were divided into four groups as follows: Sham-Control (Group 1), Control-Saline+ischemia/reperfusion (Group 2), Ticagrelor+ischemia/reperfusion (Group 3), and Enoxaparin+ischemia/reperfusion (Group 4). The ischemia/reperfusion injury model was applied to Group 2, Group 3 and Group 4. Heart tissue sections were stained with hematoxylin and eosin for histological examinations. Caspase 3 immunostaining was evaluated to detect apoptosis in the heart tissue sections.

RESULTS

Both pretreatments ameliorated the ischemic damage but especially tissue sections belonging to Group 3 were nearly similar to control levels. The results indicated that ischemia/reperfusion-induced myocardial damage was significantly increased in Group 2, whereas ticagrelor and enoxaparin pretreatments in Group 3 and Group 4 significantly decreased apoptotic scores and the histological appearance of the Group 3 close to the normal myocardium (p<0.001).

CONCLUSION

As supported by histological findings in our study, ticagrelor and enoxaparin have protective properties for heart tissue in this ischemia/reperfusion injury model.

Multidimensional Evaluation of Pulmonary Function and Exercise Capacity by BODE Index in Patients with On-Pump Coronary Artery Bypass Grafting

Coronary artery bypass grafting (CABG) often causes physiological changes in patients. Although functional changes, such as lung function and exercise capacity changes, are observed in patients, there are no detailed studies examining this. The aim was to compare preoperative and postoperative pulmonary function and exercise capacity in patients undergoing on-pump CABG with a multidimensional index (BODE index). Demographic and surgical characteristics of patients were recorded. Pulmonary function test, six-minute walk test (6MWT), and modified Medical Research Council (mMRC) dyspnea score were assessed and BODE index were calculated in preoperative and at six months postoperatively. A total of 75 patients were included with a mean ± standard deviation age of 59.8±10.0 years. The male to female ratio was 57/18. There was a statistically significant decrease in the forced expiratory flow at 25-75% (FEF_25-75%) value after CABG. Other pulmonary function test values were also lower in the postoperative period compared to the preoperative period, but these changes were not significant. The mean distance achieved in the 6MWT (p=0.02) and the mMRC dyspnea score (p=0.001) were significantly better postoperatively. The BODE index, which combines these parameters, had increased in the postoperative period. Age (OR 1.09; 95% CI: 1.008-1.181) and postoperative FEF_25-75% (OR -0.96; 95% CI: 0.938-0.988) were the independent predictors of BODE score ≥3 in multivariate analysis. Despite the decrease in pulmonary function in patients undergoing CABG, there was an improvement in exercise capacity and dyspnea score.

Does Aspartate Aminotransferase to Alanine Aminotransferase Ratio Predict Acute Kidney Injury After Cardiac Surgery?

BACKGROUND

Aspartate aminotransferase (AST) to alanine aminotransferase (ALT) ratio (AST/ALT) frequently is used in the diagnosis and prognosis of liver diseases, however it is also used in the diagnosis and prognosis of many other diseases, such as myocardial infarction, acute ischemic stroke, and peripheral artery disease. Acute kidney injury (AKI) is one of the most important complications after cardiac surgery and is one of the main causes of morbidity and mortality. The purpose of the study was to analyze the relationship between AST to ALT and AKI after isolated coronary artery bypass graft surgery (CABG).

METHODS

We retrospectively reviewed the prospectively collected data of 253 adult patients, who underwent isolated CABG surgery with normal renal function (baseline serum creatinine value <1.4 mg/dL). Preoperative (T0) and postoperative day 1 and day 3 (T1 and T2) serum AST and ALT levels were analyzed, and AST/ALT was calculated. A preoperative AST/ALT of 1.22 was found to be the best cutoff point for predicting postoperative AKI. Kidney injury was interpreted, according to RIFLE classification. The effect of AST to ALT ratio on AKI after CABG was determined using logistic regression analysis, and the results were expressed as odds ratio (OR) with a 95% confidence interval (CI). A P value < .05 was considered statistically significant.

RESULTS

Postoperative AKI occurred in 40 patients (15.8%). On logistic regression analysis, higher AST/ALT both preoperatively and postoperatively were associated with an increased incidence of postoperative AKI (T0: OR, 3.983; 95% CI, 1.940-8.180, P < .001, T1: OR, 2.760; 95% CI, 1.381-5.515, P = .004, T2: OR, 2.515; 95% CI, 1.195-5.294, P = .015).

CONCLUSION

Preoperative and postoperative elevated AST to ALT ratio seems to be associated with an increased incidence of AKI after elective isolated CABG surgery.

Changes in intraocular pressure during coronary artery bypass graft surgery: an observational study

Background

In this study, the effects of pulsatile and non-pulsatile on-pump Coronary Artery Bypass Graft surgery (CABG) and off-pump CABG techniques on the intraocular pressure were investigated.

Methods

Forty-five patients who planned to elective coronary artery bypass surgery with on-pump pulsatile (n = 15), non-pulsatile (n = 15), or off-pump (n = 15) were included. Intraocular Pressure (IOP) measurements were performed on both eyes at nine time-points: 1) Before the operation, 2) After anesthesia induction, 3) 3 minutes after heparin administration Left Internal Mammary Artery (LIMA) harvesting, 4) End of the first anastomosis, 5) End of LIMA anastomosis, 6) 3 minutes after protamine administration, 7) End of the operation, and 8) Second hour in Intensive Care Unit (ICU), 9) Fifth hour in ICU. Mean Arterial Pressure (MAP) and Central Venous Pressure (CVP) were also recorded at the same time points as IOP.

Results

In Cardiopulmonary Bypass (CPB) groups (pulsatile or non-pulsatile CPB) with the beginning of CPB, there were significant decreases in IOP values when compared to baseline (p = 0.012). This decrease was more prominent in the non-pulsatile group when compared to the pulsatile group (T₄ IOP values: pulsatile, 9.7 ± 2.6; non-pulsatile, 6.8 ± 1.9; p = 0.002; T₅ IOP values: pulsatile, 9.5 ± 1.9; non-pulsatile, 6.7 ± 2.1; p = 0.004). At the end of the surgery (T₇), IOP values returned to the baseline and stayed stable at the remaining time-points. In-off pump group, IOP values significantly increased with a head-down position (T₄ IOP values: off-pump surgery, 19.7 ± 5.2; p = 0.015). IOP values remained high until the normalization of head-down position (T₆) and stayed stable through the rest of all remaining time-points.

Conclusion

During cardiac surgery regardless of the technique (on-pump CABG, off-pump CABG), intraocular pressures remain in the normal ranges. It should be kept in mind that patients should be avoided from long and extreme Trendelenburg position, low CVP, and MAP levels during cardiac surgery to prevent eye-related complications.

Comparative Effects of Single-Dose Cardioplegic Solutions Especially in Repeated Doses During Minimally Invasive Aortic Valve Surgery

OBJECTIVE

This study aims to compare del Nido cardioplegia (DNC) and histidine-tryptophan-ketoglutarate (HTK) cardioplegic solutions in minimally invasive aortic valve replacement (mini-AVR) surgery to discuss the safety level of myocardial protection and rationale for redosing intervals.

METHODS

During the period from January 2017 to June 2019, 200 patients undergoing mini-AVR (solely or with concomitant procedures) were prospectively randomized to DNC (n = 100) andHTK (n = 100), both up to 90 minutes ischemic time. Patients with ischemic time over 90 minutes, needing a redosing, were further analyzed in 2 subgroups with DNC-R (n = 30) and HTK-R (n = 36). Sensitive biomarkers, in addition to routine biochemistry, were also documented at baseline (T1), after cessation of cardiopulmonary bypass (T2), and on the first postoperative day (T3). Transmural myocardial biopsies were sampled for staining.

RESULTS

No statistical differences could be demonstrated in DNC and HTK groups with up to 90 minutes cross-clamp times in routine biochemical measurements and basic perioperative clinical outcomes. DNC-R showed significantly more arrhythmia/AV block incidence resulting in more extended intensive care unit (ICU) stay. Interleukin-6 and syndecan-1 in DNC and DNC-R groups were substantially higher at T2. Aquaporin-4 levels were significantly lower in the DNC-R group, demonstrating unsatisfactory response of cells to an excessive volume at T2.

CONCLUSIONS

DNC and HTK provided acceptable myocardial protection as single-dose applications. DNC-R had significantly unbalanced levels of biomarkers, and more arrhythmia/AV block incidence resulting in more extended ICU stay. For patients who may need redosing HTK may be preferable to DNC.

Clinical outcomes of single-dose cardioplegia in high-risk coronary bypass

BACKGROUND

Despite the increasing popularity of single-dose cardioplegia techniques in coronary artery bypass grafting, the time window for successful reperfusion remains unclear. This study aimed to compare different cardioplegic techniques based on early and 30-day clinical outcomes via thorough monitoring.

METHODS

This prospective cohort study included high-risk patients undergoing coronary artery bypass grafting and receiving 3 different types of cardioplegia between January 2017 and June 2019. Group 1 (n = 101) had a single dose of del Nido cardioplegia, group 2 (n = 92) had a single dose of histidine-tryptophane-ketoglutarate, and group 3 (n = 119) had cold blood cardioplegia. Patients were examined perioperatively by memory loop recording and auto-triggered memory loop recording for 30 days, with documentation of predefined events.

RESULTS

Interleukin-6 and cardiac troponin levels in group 1 were significantly higher than those in groups 2 and 3. The incidence of predefined events as markers of inadequate myocardial protection was significantly higher group 1, with more frequent atrial fibrillation attacks and more hospital readmissions. The readmission rate was 17.6% in group 1, 9% in group 2, and 8% in group 3.

CONCLUSIONS

Our data demonstrate the long-term efficacy of cardioplegic techniques, which may become more crucial in high-risk patients who genuinely have a chance to benefit from adjunct myocardial protection. Patients given del Nido cardioplegia had a significantly more prominent inflammatory response and higher troponin levels after cardiopulmonary bypass. This group had issues in the longer term with significantly more cardiac events and a higher rehospitalization rate.

Subclinical Hypothyroidism Increases the Requirement of Renal Replacement Therapy After Cardiac Surgery

BACKGROUND

Subclinical or biochemically diagnosed hypothyroidism (SCH) is defined as an elevated serum thyroid-stimulating hormone (TSH) with normal free thyroxine (FT4) levels. Thyroid hormones play a major role in the normal function of the heart and vascular physiology. Atherosclerosis, increased systemic vascular resistance, and decreased arterial compliance are common pathophysiological changes that may occur in hypothyroidism. Acute kidney injury (AKI) is one of the devastating complications after cardiac surgery. Age, diabetes mellitus (DM), preexisting renal dysfunction, hypertension, impaired left ventricular function, and severe arteriosclerosis are the major risk factors for the development of AKI. The purpose of the current study was to analyze the influence of SCH on AKI and the requirement of renal replacement therapy (RRT) after isolated coronary artery bypass graft surgery (CABG).

METHODS

We retrospectively reviewed the prospectively collected data of 336 adult patients who underwent isolated CABG surgery with normal renal function (baseline serum creatinine value <1.4 mg/dL) from January 2017 to January 2019. The patients were divided into two groups either having the diagnosis of SCH (Group I, N = 47) or not (Group II, N = 289). SCH was diagnosed based on preoperative serum TSH and FT4 levels. Kidney injury was interpreted, according to RIFLE classification. The effect of SCH on AKI and the need for RRT after CABG was determined using logistic regression analysis and the results were expressed as odds ratio (OR) with a 95% confidence interval (CI). A P value < .05 was considered statistically significant.

RESULTS

Subclinical hypothyroidism was diagnosed in 14% of all patients. Postoperative AKI occurred in 15 patients (31.9%) in Group I, whereas there were 42 patients (14.5%) in Group II. On logistic regression analysis, the presence of SCH was shown to be associated with an increased incidence of postoperative AKI (OR, 0.363; 95% CI, 0.181-0.727; P = .004). RRT was used in 2.97% of patients (seven patients in Group I and three patients in Group II, P < .001). The 30-day mortality was 2.1%.

CONCLUSION

The presence of SCH seems to be associated with an increased incidence of AKI and increased requirement for RRT after cardiac surgery.

Preoperative Vitamin D Level is Associated with Postoperative Delirium After Cardiac Surgery in Patients Over 65 Years of Age

INTRODUCTION

Delirium after cardiac surgery is a devastating and important complication. Delirium is defined as "disturbance in attention (i.e., reduced ability to direct, focus, sustain, and shift attention) and awareness (reduced orientation to the environment)." In this study, we analyzed the association of preoperative vitamin D levels and postoperative delirium after cardiac surgery in patients over 65 years.

MATERIALS AND METHODS

We retrospectively reviewed the data of 212 adult patients above 65 years of age who underwent isolated coronary artery bypass graft surgery from January 2016 to January 2018. The mean age for Group I was 69.7 ± 7.4 and Group II was 70.6 ± 4.8 years. There were 112 female patients in Group I and 46 female patients in Group II. The patient population was divided into 2 groups based on preoperative serum vitamin D (25-hydroxyvitamin D [25-OHD]) levels (normal range of 25-75nmol/L). Group I included patients with preoperative serum 25-OHD level<25nmol/L. Group II included patients with preoperative serum 25-OHD level ≥25nmol/L.

RESULTS

The incidence of delirium in this study was 30.2%. In this study, 138 patients (65.1%) had preoperative serum 25-OHD levels <25 nmol/L, and 74 patients (34.9%) had preoperative serum 25-OHD levels ≥25 nmol/L. Preoperative serum 25-OHD levels were associated with postoperative delirium after coronary artery bypass graft surgery. Our retrospective study illustrated that a lower preoperative serum level of 25-OHD was associated with postoperative delirium. Our results showed that 65.1% of patients had preoperative serum 25-OHD levels <25 nmol/L, and this was associated with postoperative delirium.

CONCLUSION

Vitamin D deficiency exacerbates delirium after coronary artery bypass surgery with cardiopulmonary bypass. Whether the effects of vitamin D deficiency during this event represent separate or interrelated activities with cardiopulmonary bypass is an important question to address and prospective randomized studies are necessary to confirm these results.

Preoperative Urinary pH is Associated with Acute Kidney Injury After Cardiac Surgery in Non-Diabetic Patients

BACKGROUND

Acute kidney injury is a common complication of cardiac surgery that increases morbidity and mortality. The present study aims to analyze the association of preoperative urinary pH with acute kidney injury after isolated coronary artery bypass graft surgery (CABG).

METHODS

We retrospectively reviewed the data of 270 adult non-diabetic patients who underwent isolated CABG surgery with normal renal function. The perioperative data of the patients included demographic data, laboratory findings, morbidity, and mortality. The patient population was divided into four groups: Group I, patients with preoperative urinary pH=5; Group II, patients with preoperative urinary pH=5.5; Group III, patients with preoperative urinary pH=6-6.5; and Group IV, patients with preoperative urinary pH ≥ 7.0. Kidney injury was interpreted according to the Kidney Disease: Improving Global Outcomes (KDIGO).

RESULTS

There were 108 patients (40%) in Group I, 44 patients (16.3%) in Group II, 78 patients (28.9%) in Group III, and 40 patients (14.8%) in Group IV. Postoperative acute kidney injury (AKI) occurred in 39 patients (36.1%) in Group I, 4 patients (9.1%) in Group II, and 2 patients (2,5%) in Group III. None of the patients developed AKI in Group IV. Renal replacement therapy was required in 8 patients (2.3%) (6 patients from Group I; 2 patients from Group II; P = .016). Thirty-day mortality occurred in 5 patients (1.9%) (5 patients from Group I; none from other groups; P =  .017). All of the patients required renal replacement therapy. Logistic regression analysis revealing the presence of lower pH levels preoperatively was shown to be associated with increased incidence of postoperative AKI (OR: 0.193; 95% CI: 0.103-0.361; P < .001).

CONCLUSION

Low preoperative urinary pH (≤5.5) results in severe acute kidney injury and increases the rate of morbidity and mortality after isolated CABG.

Investigation of the protective effect of enoxaparin and ticagrelor pretreatment against ischemia-reperfusion injury in rat lung tissue

OBJECTIVES

This study was conducted to reveal the possible protective effects of ticagrelor and enoxaparin pretreatment against ischemia-reperfusion (IR)-induced injury on the lung tissue of a rat model.

METHODS

Wistar albino rats were randomly divided into 4 groups as follows: group-1 (control-sham), group-2 (control-saline+IR), group-3 (ticagrelor+IR), group-4 (enoxaparin+IR). Before the ischemic period, saline, ticagrelor, and enoxaparin were administered to the 2nd-4th groups, respectively. In these groups, IR injury was induced by clamping the aorta infrarenally for 2 h, followed by 4 h of reperfusion except group-1. After the rats were euthanized, the lungs were processed for histological examinations. Paraffin sections were stained with Haematoxylin&Eosin (H&E) for light microscopic observation. Apoptosis was evaluated by caspase-3 immunoreactivity. Data were statistically analyzed using the SPSS software.

RESULTS

In the lung sections stained with H&E, a normal histological structure was observed in group-1, whereas disorganized epithelial cells, hemorrhage, and inflammatory cell infiltration were seen in the alveolar wall in group-2. The histologic structure of the treatment groups was better than that of group-2. Caspase-3(+) apoptotic cells were noticeable in sections of group-2 and were lower in the treatment groups. In group-4, caspase-3 immunostaining was lower than in group-3. In group-2, apoptotic cells were significantly higher than in the other groups (p<0.001).

CONCLUSION

Based on the histological results, we suggested that both therapies ameliorated the detrimental effects of IR. Caspase-3 immunohistochemistry results also revealed that pre-treatment with enoxaparin gave better results in an IR-induced rat injury model. In further studies, other parameters such as ROS and inflammatory gene expressions should be evaluated for accurate results.

Effect of Iloprost, a Prostacyclin Analogue, on Myocardial Ischemia-Reperfusion Injury

Myocardial ischemia-reperfusion injury continues to be observed during open heart surgery. Various experimental models have been developed to overcome this injury and to increase postoperative prognosis. This study was conducted to assess the effect that iloprost, a prostacyclin analogue, can have on myocardial ischemia-reperfusion injury. We evaluated tissue damage by measuring the levels of malonyldialdehyde (MDA), glutathione, and nitric oxide (NO) in tissue and perfusates. In this study, 20 guinea pig hearts were prepared by using the modified Langendorff perfusion apparatus to form control (n = 10) and experimental study groups (n = 10). Following a preischemic period of perfusion and an ischemic period of 20 minutes, control hearts were perfused with Krebs–Henseleit solution. In the experimental group, iloprost (0.45 μg/kg per hour) was included in the perfusates for the last 10 minutes of the preischemic phase. Following cardiac stabilization, heart rate (pulse/min), contractility (mm), and aortic pressure (mmHg) values were recorded at the end of preischemia, postischemia, and reperfusion. Perfusate and tissue analyses for glutathione, MDA, and NO levels were made in each group at the end of experiments. Iloprost was found to have protective effects against myocardial ischemia by means of increased myocardial contractility, decreased tissue/perfusate glutathione levels and inhibited rise of tissue/perfusate MDA observed in the iloprost-treated experimental group. Future investigations on myocardial ischemia-reperfusion injury must evaluate iloprost-related mechanisms.

Circulating microRNAs as Novel Biomarkers for Atherosclerosis

BACKGROUND/AIM

In this study, we determined the expression of selected circulating microRNAs (miRNA) and their potential roles as biomarkers in patients with atherosclerosis and a control group.

MATERIALS AND METHODS

In order to obtain insight into miRNA expression levels in atherosclerosis, we analyzed miRNA expression levels by real-time polymerase chain reaction (RT-PCR) in case (n=89) and healthy control (n=93) groups. Receiver operating characteristic curve analysis was performed to assess the diagnostic capability of miRNAs.

RESULTS

miRNA221 and miRNA221 expression levels were significantly lower in patients than controls (p=0.011 and p=0.004, respectively). Receiver operator curve analysis demonstrated that expression levels of miRNA221 [area under curve (AUC)=0.623, p=0.0086) and miRNA222 (AUC=0.654, p=0.0006) were significantly different between groups. There were positive correlations between miRNA122a and triglyceride (p=0.046) and very-low-density lipoprotein (p=0.029) levels.

CONCLUSION

miRNA221 and miRNA222 could be convenient biomarkers for diagnosis of atherosclerosis.

Use of cerebral oxygen saturation and hemoglobin concentration to predict acute kidney injury after cardiac surgery

Objective

Acute kidney injury (AKI) is a common complication after cardiac surgery and is associated with significant morbidity and mortality. Near infrared spectroscopy (NIRS) is a noninvasive technique for real-time measurement of cerebral tissue oxygenation. The purpose of the present study was to evaluate the correlation of AKI with hemoglobin and regional cerebral oxygen saturation (rScO₂) measured intraoperatively and postoperatively in patients undergoing cardiac surgery.

Methods

We retrospectively analyzed the prospectively collected data of 45 adult patients with normal renal function who underwent isolated coronary artery bypass grafting (CABG) from January 2014 to May 2014. Kidney injury was assessed according to the Acute Kidney Injury Network criteria. rScO₂ and hemoglobin were measured every hour intraoperatively and for the first 24 hours postoperatively.

Results

The hemoglobin concentration and rScO₂ were significantly lower in patients with than without AKI, and no linear trends were observed. No exact cut-off values were obtained.

Conclusion

This retrospective study shows that a lower rScO₂ and hemoglobin concentration are correlated with AKI after CABG in patients with no peripheral vascular disease or recent myocardial infarction. We suggest that cerebral oximetry alone may predict postoperative AKI well.

Hemoglobin A1c Levels Predicts Acute Kidney Injury after Coronary Artery Bypass Surgery in Non-Diabetic Patients

INTRODUCTION:

Elevated hemoglobin A1c levels in patients with diabetes mellitus have been known as a risk factor for acute kidney injury after coronary artery bypass grafting. However, the relationship between hemoglobin A1c levels in non-diabetics and acute kidney injury is under debate. We aimed to investigate the association of preoperative hemoglobin A1c levels with acute kidney injury in non-diabetic patients undergoing isolated coronary artery bypass grafting.

METHODS:

202 non-diabetic patients with normal renal function (serum creatinine <1.4 mg/dl) who underwent isolated coronary bypass were analyzed. Hemoglobin A1c level was measured at the baseline examination. Patients were separated into two groups according to preoperative Hemoglobin A1c level. Group 1 consisted of patients with preoperative HbA1c levels of < 5.6% and Group 2 consisted of patients with preoperative HbA1c levels of ≥ 5.6%. Acute kidney injury diagnosis was made by comparing baseline and postoperative serum creatinine to determine the presence of predefined significant change based on the Kidney Disease Improving Global Outcomes (KDIGO) definition.

RESULTS:

Acute kidney injury occurred in 19 (10.5%) patients after surgery. The incidence of acute kidney injury was 3.6% in Group 1 and 16.7% in Group 2. Elevated baseline hemoglobin A1c level was found to be associated with acute kidney injury (P=0.0001). None of the patients became hemodialysis dependent. The cut off value for acute kidney injury in our group of patients was 5.75%.

CONCLUSION:

Our findings suggest that, in non-diabetics, elevated preoperative hemoglobin A1c level may be associated with acute kidney injury in patients undergoing coronary artery bypass grafting. Prospective randomized studies in larger groups are needed to confirm these results.

Urine Output during Cardiopulmonary Bypass Predicts Acute Kidney Injury after Coronary Artery Bypass Grafting

OBJECTIVE

This study evaluated the relationship between the amount of urinary output during cardiopulmonary bypass and acute kidney injury in the postoperative period of coronary artery bypass grafting.

METHODS

Two hundred patients with normal preoperative serum creatinine levels, operated on with isolated CABG between 2012-2014 were investigated retrospectively. The RIFLE (Risk, injury, failure, loss of function, and end-stage renal disease) risk scores were calculated for each patient in the third postoperative day. Patients were distributed into two groups in relation to the presence of acute kidney injury or not and these two groups were compared.

RESULTS

The urinary output (mL/kg/hour) during cardiopulmonary bypass in the acute kidney injury negative group was significantly higher than in the acute kidney injury positive group (P = .022). In case of a urinary output value 3.70 and lower to predict acute kidney injury positivity, sensitivity was detected as 71.43%. Results of the analysis for urinary output predict positivity of acute kidney injury.

CONCLUSION

We suggest that urine output during cardiopulmonary bypass is a significant criteria that could predict acute kidney injury following coronary artery bypass grafting with cardiopulmonary bypass. Attempts to increase the urine output during cardiopulmonary bypass could help to maintain the renal functions during and after surgery.

Preoperative Low Serum Albumin Levels Increase the Requirement of Renal Replacement Therapy after Cardiac Surgery

BACKGROUND

Acute kidney injury is a common complication of cardiac surgery that increases morbidity and mortality. The aim of the present study is to analyze the association of preoperative serum albumin levels with acute kidney injury and the requirement of renal replacement therapy after isolated coronary artery bypass graft surgery (CABG).

METHODS

We retrospectively reviewed the prospectively collected data of 530 adult patients who underwent isolated CABG surgery with normal renal function. The perioperative clinical data of the patients included demographic data, laboratory data, length of stay, in-hospital complications and mortality. The patient population was divided into two groups: group I patients with preoperative serum albumin levels &lt;3.5 mg/dL; and group II pateints with preoperative serum albumin levels ≥3.5 mg/dL.

RESULTS

There were 413 patients in group I and 117 patients in group II. Postoperative acute kidney injury (AKI) occured in 33 patients (28.2%) in group I and in 79 patients (19.1%) in group II. Renal replacement therapy was required in 17 patients (3.2%) (8 patients from group I; 9 patients from group II; P = .018). 30-day mortality occurred in 18 patients (3.4%) (10 patients from group I; 8 patients from group II; P = .037). Fourteen of these patients required renal replacement therapy. Logistic regression analysis revealing the presence of lower serum albumin levels preoperatively was shown to be associated with increased incidence of postoperative AKI (OR: 1.661; 95% CI: 1.037-2.661; P = .035). Logistic regression analysis also revealed that DM (OR: 3.325; 95% CI: 2.162-5.114; P = .000) was another independent risk factor for AKI after isolated CABG.

CONCLUSION

Low preoperative serum albumin levels result in severe acute kidney injury and increase the rate of renal replacement therapy and mortality after isolated CABG.

The Influence of Metabolic Syndrome on Acute Kidney Injury Occurrence after Coronary Artery Bypass Grafting

BACKGROUND

Metabolic syndrome (MetS) is defined as a cluster of systemic abnormalities: hyperglycemia, dyslipidemia, abdominal obesity, and hypertension. Acute kidney injury (AKI) is one of the devastating complications after cardiac surgery. Age, DM, preexisting renal dysfunction, hypertension, impaired left ventricular function, and severe arteriosclerosis of the aorta are the major risk factors for the development of AKI. The purpose of the current study was to analyze the influence of MetS on AKI occurring after coronary artery bypass grafting (CABG).

METHODS

We retrospectively reviewed the prospectively collected data of 500 adult patients who underwent isolated CABG surgery with normal renal function (baseline serum creatinine value &lt;1.4 mg/dL) from January 2011 to January 2015. The patients were divided into two groups either having the diagnosis of MetS (Group I) or not (Group II). MetS was diagnosed based on International Diabetes Federation definition. Kidney injury was interpreted according to RIFLE classification. The effect of MetS on AKI after CABG was determined using logistic regression analysis and the results were expressed as odds ratio (OR) with a 95% confidence interval (CI). A P value &lt;.05 was considered statistically significant.

RESULTS

Metabolic syndrome was diagnosed in 16.4% of all patients. Postoperative AKI occurred in 26 patients (31.7%) in Group I whereas there were 53 patients (12.7%) in Group II. On logistic regression analysis, the presence of MetS was shown to be associated with increased incidence of postoperative AKI (OR, 3.197; 95% CI, 1.850-5.526; P = .000).

CONCLUSION

The presence of MetS seems to be associated with increased incidence of AKI after cardiac surgery. MetS is a modifiable issue; if its components are well controlled its dreadful effects after cardiac surgery might be controlled as well.

Ticagrelor Attenuates Apoptosis of Lung and Myocardial Cells Induced by Abdominal Aorta Ischemia/Reperfusion

AIM

This study aimed to analyze the effect of ticagrelor pretreatment on the prevention of lung and heart injury induced by abdominal aorta ischemia and reperfusion (I/R) and also to determine the effective dose.

MATERIALS AND METHODS

Thirty-five male Sprague-Dawley rats weighing 350-400 g were randomized into five groups. The animals received ticagrelor at doses of 7.5 mg/kg, 15 mg/kg and 25 mg/kg or normal saline 0.1 ml/kg orally via gastric gavage before the ischemic period. In the control and study groups, I/R injury was induced by clamping the aorta infrarenally for 2 hs, followed by 4 h of reperfusion. After sacrifice, hearts and lungs of the animals were extracted for both histopathological and biochemical analysis.

RESULTS

There was a significant difference between the animals that received 7.5 mg/kg and 25 mg/kg and 15 mg/kg and 25 mg/kg dose of ticagrelor regarding tissue malondealdehyde (MDA), and glutathione reductase levels in both lung and heart Ticagrelor treatment at 25 mg/kg led to significant cardiac remodeling activity and normal lung architecture against I/R induced injury. The number of TdT-mediated dUTP nick-end labeling (TUNEL)-positive cells in alveolar epithelium and myocytes were increased in the sections from saline (I/R) group rats, and decreased following 25 mg/kg ticagrelor treatment.

CONCLUSION

Ticagrelor dose-dependently inhibits platelet aggregation, increases cyclooxygenase-2 and also inhibits cellular uptake of adenosine all resulting in attenuation of I/R injury. Ticagrelor at 25 mg/kg was determined as the dose effective against I/R-induced injury in lung and heart in Sprague-Dawley rats in the present study.

Renal Artery Occlusion Due to Aortic Dissection Caused by Blunt Trauma

In this report, our aim is to present a case of renal artery occlusion due to type-3 acute aortic dissection following blunt trauma. A twenty-four-year-old male patient was admitted to the emergency department of our hospital with pain in his abdomen and on his back 3 hours after a blunt abdominal trauma due to an industrial injury. After consultation with the urology department, the patient was taken to operation to be evaluated for an intervention for aortic dissection and nephrectomy.

Polymorphisms of MMP9 and TIMP2 in Patients with Varicose Veins

BACKGROUND

Genetic predisposition is a suggested risk factor in the etiology of varicose veins. The matrix metalloproteinase (MMP) family degrades extracellular matrix (ECM) and may lead to disturbances in vein wall structure. The activity of MMPs in the ECM are controlled by specific tissue inhibitors of MMPs (TIMP). The present study aimed to investigate the relationship between MMP9 and TIMP2 gene polymorphisms and varicose vein risk.

MATERIALS AND METHODS

Genotyping of the polymorphisms of MMP9 (1562 C/T) and TIMP2 (418G/C) was performed using polymerase chain reaction and restriction-fragment length polymorphism assays in a group of patients with varicose veins (n=63) and healthy controls (n=70).

RESULTS

The frequencies of MMP9 alleles and genotypes did not differ significantly between patient and control groups. However, TIMP2 -418 C allele was associated with increased risk for varicose vein formation (p=0.007). It was also shown that the frequency of the GG genotype was significantly higher in the control group than in the patient group (odds ratio=0.333, 95% confidence interval=0.14-0.78, p=0.012).

CONCLUSION

TIMP2 -418 C allele is associated with susceptibility for varicose vein formation and individuals with GG genotype may have a lower risk for varicose vein formation.

Expression levels of elastin and related genes in human varicose veins

Among the suspected reasons for varicose vein formation are changes in the quantity and content of the elastin protein; however, comprehensive investigations about elastin assembly in varicose vein formation are yet lacking. In this study, we aimed to determine the changes in mRNA levels of elastin and some of its functionally related proteins, fibulin 5, LOXL-1, MMP-2 and MMP-9 in varicose vein formation. We analysed the mRNA levels of elastin, fibulin-5, LOXL1, MMP2 and MMP9 in samples of 35 healthy and 35 varicose great saphenous vein tissues. mRNA levels of these genes were determined by using real-time PCR and normalized with HPRT1. When we compared the patient and control groups, elastin mRNA levels were significantly higher in the patient group than in the control group (P = 0.047), although there were no significant differences in fibulin 5, LOXL1, MMP2 and MMP9 mRNA levels between the patient and control groups. We showed that up-regulation of MMP2 mRNA expression was significantly correlated with hyperlipidaemia (P = 0.029). The up-regulation of elastin expression may play an important role in the pathogenesis of primary varicose veins. Additionally, the up-regulation of MMP2 expression was strongly correlated with hyperlipidaemia in varicose veins.

Furosemide infusion prevents the requirement of renal replacement therapy after cardiac surgery

OBJECTIVE

Acute kidney injury (AKI) is a devastating complication following cardiac surgery and the ideal management is controversial. This prospective, randomized, open-label and double-blinded study analyzed the renoprotective effects of furosemide infusion and intermittent bolus therapy administered with dopamine infusion in cardiac surgical patients.

METHODS

Between August 1, 2007 and July 31, 2008, 100 adult patients undergoing elective coronary artery bypass surgery (CABG) surgery with normal renal function (creatinine <1.4 mg/dl) were enrolled in the study. The patients were randomized for the comparison of intermittent (Group 1, n=50, 1mg-3mg/kg) and continuous infusion of furosemide (Group 2, n=50, 10mg/ml). Continuous variables were expressed as mean+/- SD and compared by unpaired Student's t test or ANOVA for repeated measures. Statistical significance was assumed if p value was <0.05.

RESULTS

Renal replacement therapy (RRT) was used in 5% of patients (all in group 1, p=0.028). The 30-day mortality was 5%. Only 2 patients became hemodialysis dependent in group 1. Group 2 patients showed a continuous and higher urine output postoperatively than group 1 (p<0.001). Both groups had significant increase in peak postoperative serum creatinine values (p<0.001), however peak postoperative creatinine-clearance was significantly lower in group 1 (p<0.001).

CONCLUSION

Acute kidney injury necessitating RRT makes a small percentage of patients undergoing cardiac surgery and if RRT is not required the survival is excellent. Continuous infusion of furosemide seems to be effective in promoting diuresis and decreasing the need for RRT. However further multicenter studies with different doses of furosemide are required to confirm these results.