Cardiac surgery-associated acute kidney injury (CS-AKI) is a major complication associated with increased morbidity and mortality. There are multiple diagnostic criteria for CS-AKI. Despite many new investigations available for improved...

An unavoidable consequence of cardiac surgery is oxidative stress and resulting peroxidation of biological molecules, in particular unsaturated lipids. The detection of peroxidation metabolites in biological environments is difficult due to their large variety, small concentration, and high reactivity. One of the most studied lipid peroxidation products is malondialdehyde and as such an important marker of oxidative stress. The aim of this study was to monitor the perioperative serum concentration of malondialdehyde as an oxidative stress marker in patients undergoing arrested-heart cardiopulmonary bypass surgery. This observational study was performed on 40 patients scheduled for on-pump arrested-heart open-heart surgery. Blood samples for the analysis of serum malondialdehyde were obtained preoperatively and intraoperatively immediately after the aortic clamp was removed. Afterwards, samples were obtained 12, 24, 48 and 72 h postoperatively. A gas chromatography-mass spectrometry analytical method was used to detect serum concentrations of malondialdehyde. A significant increase in serum malondialdehyde concentration was detected at the time of aortic declamping. The malondialdehyde serum concentration continued to increase and peaked 12 h postoperatively. Afterwards it started to decline, but remained significantly higher compared to preoperative values both at 24 and 48 h postoperatively. In contrast to some previous studies, our results demonstrate that in this patient population, the malondialdehyde levels do not peak at the end of the surgery, but continue to rise a few hours after surgery. Our findings indicate that in this patient population, oxidative stress with consequent lipid peroxidation is maintained and is even attenuated in the early postoperative period. This study was registered with the ISRCTN Registry under the trial registration number ISRCTN98572043.

Background: Heart failure with preserved ejection fraction (HFpEF) is a complex and heterogeneous clinical syndrome. In the absence of effective and potent treatment strategies, the main challenge in HFpEF management remains the availability of strong predictors of unfavourable outcomes. In our study, we sought to evaluate the potential prognostic value of heart rate turbulence (HRT) and variability (HRV) parameters on mortality in ambulatory HFpEF patients. Methods: This was a case–control study comparing HRT and HRV parameters in HFpEF survivors vs. non-survivors. Patients from the RESPOND Heart Failure Registry with HFpEF who underwent 24 h ECG monitoring (Holter) were included; HRT parameters (i.e., turbulence onset (TO) and turbulence slope (TS)) and HRV parameters (i.e., standard deviation of NN intervals (SDNN)) derived from 24 h Holter ECGs were calculated in patients who died within 12 months, and compared to their age-, gender-, LVEF-, ECHO-, aetiology-, and therapy-matched alive controls. Results: A total of 22 patients (mean age 80 ± 7 years, 18% female, mean LVEF 57 ± 9%) were included in the final analysis. In deceased patients, values of TO were significantly higher, and values of TS and SDNN were significantly lower as compared to survivors. Conclusions: HRT and HRV parameters have the ability to differentiate individuals with HFpEF who are at the greatest risk of unfavourable outcomes. The extent of autonomic disbalance as determined by HRT and HRV could potentially assist in the prognostic assessment and risk stratification of HFpEF patients.

Left ventricular pseudoaneurysm is a partial cardiac rupture, contained by the surrounding pericardium that maintains communication with the left ventricular lumen. Whereas most cases of left ventricular pseudoaneurysms are related to myocardial infarction (loss of myocardial integrity), only a handful are associated with valve surgery. We present a female patient, who was admitted for elective mitral valve replacement. After the implantation of the mechanical valve, we encountered a rupture of the atrioventricular groove. After 3 months, a left ventricular pseudoaneurysm was found and the patient was reoperated. The valve was explanted and the inspection of the annulus and previously implanted pericardial patch revealed a loosened stitch on the inferior (ventricular) side. The defect was reinforced with additional stitches and the valve was reimplanted. In conclusion, we report an unusual case with two serious complications after mitral valve replacement – atrioventricular groove rupture and left ventricular pseudoaneurysm.

Objectives Acute kidney injury (AKI) is associated with higher perioperative mortality and morbidity. Oxidative stress has been proposed as a cause of postoperative AKI. Ascorbic acid (AA) supplementation was suggested as a novel and promising antioxidant. The aim of this study was to evaluate the capability of AA to reduce the incidence of postoperative AKI in cardiac surgery patients.Methods A prospective randomized trial was conducted in patients scheduled for on-pump cardiac surgery. Subjects in the AA group received 2 g of AA intravenously during the induction of anesthesia, 2 g before aortic cross-clamp removal and 1 g every 8 hours for five postoperative days (the JERICA protocol). Postoperatively, the patients were monitored for AKI and other complications. Malondialdehyde levels were monitored in a subpopulation of 100 patients to evaluate the effect of AA on oxidative stress level.Results The AA and control group consisted of 163 and 169 patients, respectively. The groups were well matched for baseline demographics and had similar intraoperative characteristics. The incidence of AKI in the AA and control group was 20.9 and 28.4%, respectively (p = 0.127). The estimated glomerular filtration rate did not differ between the study groups in the entire postoperative period. There was a trend toward higher malondialdehyde values with statistical significance on postoperative day 1 and lower in-hospital mortality in the AA group (0.6 vs. 4.1%, p = 0.067).Conclusion Our results do not support the effectiveness of AA supplementation in reducing the incidence of postoperative AKI in on-pump cardiac surgery patients.Clinical Registration Number This study was registered with the ISRCTN Registry under the trial registration number ISRCTN98572043.

Background and Objectives: Postoperative atrial fibrillation (POAF) is a common complication following cardiac surgery, associated with increased morbidity and prolonged hospital stays. Oxidative stress has been implicated in POAF pathogenesis, with malondialdehyde (MDA), a marker of lipid peroxidation, proposed as a potential biomarker. However, conflicting evidence exists regarding its predictive value. This study aimed to assess the association between serum MDA levels and POAF incidence in patients undergoing cardiac surgery. Materials and Methods: This prospective observational study included 99 consecutive patients undergoing elective on-pump cardiac surgery. Patients with preoperative atrial fibrillation, chronic kidney disease requiring dialysis, or emergency surgery were excluded. Blood samples for MDA measurement were collected at six perioperative time points: preoperatively, intraoperatively after aortic clamp release, and at 8, 24, 48, and 72 h postoperatively. Patients were monitored for new-onset POAF during the first three postoperative days. Statistical analyses included independent samples t-tests, Mann–Whitney U-tests, and Fisher’s exact tests, with significance set at p < 0.05. Results: POAF occurred in 33 (33%) patients. Patients who developed POAF were significantly older (p = 0.017) and had higher EuroSCORE II values (p = 0.019). No significant differences were observed in serum MDA concentrations between POAF and non-POAF patients at any measured time point. The incidence of POAF was higher in patients undergoing valvular surgery (p = 0.014). Conclusions: Serum MDA levels were not associated with POAF development, suggesting that lipid peroxidation alone may not play a central role in POAF pathogenesis. These findings challenge the predictive value of MDA for POAF risk stratification. Future research should explore alternative oxidative stress markers and their potential therapeutic implications in POAF prevention.