Search Results (18)

Background and Objectives: Effective myocardial protection is essential for successful cardiac surgery outcomes, especially in complex and prolonged procedures. To this end, Del Nido (DN) and histidine-tryptophan-ketoglutarate (HTK) cardioplegia solutions are widely used; however, their comparative efficacy in adult surgeries with prolonged aortic cross-clamp (ACC) times remains unclear. This study aimed to compare the efficacy and safety of DN and HTK for myocardial protection during prolonged ACC times in adult cardiac surgery and to define clinically relevant thresholds. Materials and Methods: This retrospective study included a total of 320 adult patients who underwent cardiac surgery under cardiopulmonary bypass (CPB) with an aortic cross-clamp time ≥ 90 min. Data were collected from the medical records of elective adult cardiac surgery cases performed at a single center between 2019 and 2025. Patients were categorized into two groups based on the type of cardioplegia received: Del Nido (n = 160) and HTK (n = 160). The groups were compared using 1:1 propensity score matching. Clinical and biochemical outcomes—including troponin I (TnI), CK-MB, lactate levels, incidence of low cardiac output syndrome (LCOS), and need for mechanical circulatory support—were analyzed between the two cardioplegia groups. Subgroup analyses were performed according to ACC duration (90–120, 120–150, 150–180 and >180 min). The predictive threshold of ACC duration for each complication was determined by ROC analysis, followed by the analysis of independent predictors of each endpoint by multivariate logistic regression. Results: Intraoperative cardioplegia volume and transfusion requirements were lower in the DN group (p < 0.05). HTK was associated with lower TnI levels and less intra-aortic balloon pump (IABP) requirement at ACC times exceeding 180 min. Markers of myocardial injury were lower in patients with an ACC duration of 120–150 min in favor of HTK. The propensity for ventricular fibrillation after ACC was significantly lower in the DN group. Significantly lower postoperative sodium levels were observed in the HTK group. Prolonged ACC duration was an independent risk factor for LCOS (odds ratio [OR]: 1.023, p < 0.001), VIS > 15 (OR, 1.015; p < 0.001), IABP requirement (OR: 1.020, p = 0.002), and early mortality (OR: 1.016, p = 0.048). Postoperative ejection fraction (EF), troponin I, and CK-MB levels were associated with the development of LCOS and a VIS > 15. Furthermore, according to ROC analysis, HTK cardioplegia was able to tolerate ACC for up to a longer duration in terms of certain complications, suggesting a higher physiological tolerance to ischemia. Conclusions: ACC duration is a strong predictor of major adverse outcomes in adult cardiac surgeries. Although DN cardioplegia is effective and economically advantageous for shorter procedures, HTK may provide superior myocardial protection in operations with long ACC duration. This study supports the need to individualize cardioplegia choice according to ACC duration. Further prospective studies are needed to establish standard dosing protocols and to optimize cardioplegia selection according to surgical duration and complexity. Full article

Ventricular septal defects (VSDs) can lead to congestive heart failure and pulmonary hypertension, particularly in patients with large shunts. However, no surgical treatment for feline VSD has been reported. Here, we elucidated the first surgical correction of an infundibular muscular VSD in a one-year-old Ragdoll cat, atypically located and classified under the Soto classification rather than the standard Kirklin classification, through cardiac arrest using cardiopulmonary bypass—a method rarely used in feline cardiac surgery. Detailed echocardiography revealed that the defect required intervention owing to left heart and main pulmonary artery enlargement. Despite the VSD being located on the contralateral side, as anticipated in the preoperative examinations, the choice of median sternotomy allowed for the successful closure of the defect. Conversely, the insertion of two cannulas into the ascending aorta resulted in damage to the adjacent thoracic duct, causing transient chylothorax, which was resolved with conservative treatment. Cardiac arrest induced by a cardioplegic solution facilitated the surgical procedure, although it leads to anemia in cats. However, on postoperative day 490, the patient exhibited only minor residual shunting, with normalized heart size, and remained healthy. This technique appears to be a viable treatment option for congenital heart disease in cats. Full article

Gas-loaded nanocarriers (G-LN) show promise in improving heart transplantation (HTx) outcomes. Given their success in reducing cell death during normothermic hypoxia/reoxygenation (H/R) in vitro, we tested their integration into cardioplegic solutions and static cold storage (SCS) during simulated HTx. Wistar rat hearts underwent four hours of SCS with four G-LN variants: O₂- or N₂-cyclic-nigerosyl-nigerose-nanomonomers (CNN), and O₂- or N₂-cyclic-nigerosyl-nigerose-nanosponges (CNN-NS). We monitored physiological-hemodynamic parameters and molecular markers during reperfusion to assess cell damage/protection. Hearts treated with nanomonomers (N₂-CNN or O₂-CNN) showed improvements in left ventricular developed pressure (LVDP) and a trend towards faster recovery of the rate pressure product (RPP) compared to controls. However, nanosponges (N₂-CNN-NS or O₂-CNN-NS) did not show similar improvements. None of the groups exhibited an increase in diastolic left ventricular pressure (contracture index) during reperfusion. Redox markers and apoptosis/autophagy pathways indicated an increase in Beclin 1 for O₂-CNN and in p22phox for N₂-CNN, suggesting alterations in autophagy and the redox environment during late reperfusion, which might explain the gradual decline in heart performance. The study highlights the potential of nanomonomers to improve early cardiac performance and mitigate cold/H/R-induced stunning in HTx. These early improvements suggest a promising avenue for increasing HTx success. Nevertheless, further research and optimization are needed before clinical application. Full article

Myocardial protection has become an essential adjunctive procedure in veterinary cardiac surgery. Del Nido cardioplegia is a good alternative to the traditional St. Thomas II (ST) cardioplegia in open heart surgery in humans. This study aims to compare intra- and postoperative results between ST cardioplegia and modified del Nido (mDN) cardioplegia in mitral valve surgery in dogs with myxomatous mitral valve disease (MMVD). This retrospective study was conducted using clinical records of 16 MMVD dogs that underwent either ST or mDN cardioplegia. We measured cardiopulmonary bypass (CPB) time, aortic cross-clamp (ACC) time, total operation time, the number of cardioplegia doses, total amount of cardioplegia, required defibrillations, in-hospital mortality and pre- and one-month postoperative echocardiographic variables. CPB (159.4 ± 16.1 vs. 210.1 ± 34.0 min), ACC (101.4 ± 7.0 vs. 136.0 ± 24.8 min) and total operation time (262.3 ± 13.1 vs. 327.0 ± 45.4 min) were significantly shorter in the mDN group (p < 0.05). The number of cardioplegia doses (3.25 ± 0.4 vs. 6.25 ± 1.2) and total amount of cardioplegia (161.3 ± 51.5 vs. 405.0 ± 185.9 mL) in the mDN group were also significantly smaller than the ST group (p < 0.05). No difference was observed in the requirement of defibrillation, in-hospital mortality and pre- and postoperative echocardiographic variables. The utilization of mDN cardioplegia was associated with shorter operative time in mitral valve surgery in dogs. Full article

Nanocarriers for oxygen delivery have been the focus of extensive research to ameliorate the therapeutic effects of current anti-cancer treatments and in the organ transplant field. In the latter application, the use of oxygenated cardioplegic solution (CS) during cardiac arrest is certainly beneficial, and fully oxygenated crystalloid solutions may be excellent means of myocardial protection, albeit for a limited time. Therefore, to overcome this drawback, oxygenated nanosponges (NSs) that can store and slowly release oxygen over a controlled period have been chosen as nanocarriers to enhance the functionality of cardioplegic solutions. Different components can be used to prepare nanocarrier formulations for saturated oxygen delivery, and these include native α-cyclodextrin (αCD), αcyclodextrin-based nanosponges (αCD-NSs), native cyclic nigerosyl-nigerose (CNN), and cyclic nigerosyl-nigerose-based nanosponges (CNN-NSs). Oxygen release kinetics varied depending on the nanocarrier used, demonstrating higher oxygen release after 24 h for NSs than the native αCD and CNN. CNN-NSs presented the highest oxygen concentration (8.57 mg/L) in the National Institutes of Health (NIH) CS recorded at 37 °C for 12 h. The NSs retained more oxygen at 1.30 g/L than 0.13 g/L. These nanocarriers have considerable versatility and the ability to store oxygen and prolong the amount of time that the heart remains in hypothermic CS. The physicochemical characterization presents a promising oxygen-carrier formulation that can prolong the release of oxygen at low temperatures. This can make the nanocarriers suitable for the storage of hearts during the explant and transport procedure. Full article

The long saphenous vein is the most used conduit in cardiac surgery, but its long-term patency is limited by vein graft disease (VGD). Endothelial dysfunction is a key driver of VGD; its aetiology is multi-factorial. However emerging evidence identifies vein conduit harvest technique and preservation fluids as causal in their onset and propagation. This study aims to comprehensively review published data on the relationship between preservation solutions, endothelial cell integrity and function, and VGD in human saphenous veins harvested for CABG. The review was registered with PROSPERO (CRD42022358828). Electronic searches of Cochrane Central Register of Controlled Trials, MEDLINE, and EMBASE databases were undertaken from inception until August 2022. Papers were evaluated in line with registered inclusion and exclusion criteria. Searches identified 13 prospective, controlled studies for inclusion in the analysis. All studies used saline as a control solution. Intervention solutions included heparinised whole blood and saline, DuraGraft, TiProtec, EuroCollins, University of Wisconsin (UoW), buffered, cardioplegic and Pyruvate solutions. Most studies demonstrated that normal saline appears to have negative effects on venous endothelium and the most effective preservation solutions identified in this review were TiProtec and DuraGraft. The most used preservation solutions in the UK are heparinised saline or autologous whole blood. There is substantial heterogeneity both in practice and reporting of trials evaluating vein graft preservation solutions, and the quality of existing evidence is low. There is an unmet need for high quality trials evaluating the potential for these interventions to improve long-term patency in venous bypass grafts. Full article

Introduction: Cardioplegia is a pharmacological approach essential for the protection of the heart from ischemia–reperfusion (I–R) injury. Over the years, numerous cardioplegic solutions have been developed, with each cardioplegic approach having its advantages and disadvantages. Cardioplegic solutions can be divided into crystalloid and blood cardioplegic solutions, and an experienced surgeon chooses the type of solution based on the individual needs of patients in order to provide optimal heart protection. Importantly, the pediatric immature myocardium is structurally, physiologically, and metabolically different from the adult heart, and consequently its needs to achieve cardioplegic arrest strongly differ. Therefore, the present review aimed to provide a summary of the cardioplegic solutions available to pediatric patients with a special focus on emphasizing differences in heart injury after various cardioplegic solutions, the dosing strategies, and regimens. Material and methods: The PubMed database was searched using the terms cardioplegia, I–R, and pediatric population, and studies that investigated the influence of cardioplegic strategies on markers of cardiac muscle damage were further analyzed in this review. Conclusions: A large body of evidence suggested more prominent benefits achieved with blood compared to those with crystalloid cardioplegia in pediatric myocardium preservation. However, standardized and uniform protocols have not been established so far, and an experienced surgeon chooses the type of cardioplegia solution based on the individual needs of patients, while the severity of myocardial damage strongly depends on the type and duration of the surgical procedure, overall patient condition, and presence of comorbidities, etc. Full article

Open-heart surgery is often an unavoidable option for the treatment of cardiovascular disease and prevention of cardiomyopathy. Cardiopulmonary bypass surgery requires manipulating cardiac contractile function via the perfusion of a cardioplegic solution. Procedure-associated ischemia and reperfusion (I/R) injury, a major source of oxidative stress, affects postoperative cardiac performance and long-term outcomes. Using large-scale liquid chromatography–tandem mass spectrometry (LC-MS/MS)-based metabolomics, we addressed whether cardioplegic solutions affect the baseline cellular metabolism and prevent metabolic reprogramming by oxidative stress. AC16 cardiomyocytes in culture were treated with commonly used cardioplegic solutions, High K⁺ (HK), Low K⁺ (LK), Del Nido (DN), histidine–tryptophan–ketoglutarate (HTK), or Celsior (CS). The overall metabolic profile shown by the principal component analysis (PCA) and heatmap revealed that HK or LK had a minimal impact on the baseline 78 metabolites, whereas HTK or CS significantly repressed the levels of multiple amino acids and sugars. H₂O₂-induced sublethal mild oxidative stress causes decreases in NAD, nicotinamide, or acetylcarnitine, but increases in glucose derivatives, including glucose 6-P, glucose 1-P, fructose, mannose, and mannose 6-P. Additional increases include metabolites of the pentose phosphate pathway, D-ribose-5-P, L-arabitol, adonitol, and xylitol. Pretreatment with HK or LK cardioplegic solution prevented most metabolic changes and increases of reactive oxygen species (ROS) elicited by H₂O₂. Our data indicate that HK and LK cardioplegic solutions preserve baseline metabolism and protect against metabolic reprogramming by oxidative stress. Full article

Background: We aimed to analyse the performance of minimal invasive extracorporeal circulation (MiECC) concomitantly with Microplegia, in patients with recent myocardial infarction (MI) undergoing urgent coronary artery bypass grafting (CABG) surgery. Methods: We included patients with a recent MI (≤7 days) undergoing isolated CABG surgery using MiECC. The primary endpoint was a major cardiovascular or cerebrovascular event (MACCE). In a secondary analysis, we compared our institutional Microplegia concept with the use of a crystalloid single-shot cardioplegic solution. Results: In total, 139 patients (mean ± standard deviation (SD) age 66 ± 10 years) underwent urgent CABG surgery using Microplegia; 55% (n = 77) of the patients had an acute MI within 1–7 days preoperatively; 20% (n = 28) had an acute MI within 6–24 h; and 24% (n = 34) had an acute MI within <6 h preoperatively. The number of distal anastomoses was a geometric mean of 4 (95% confidence interval 3–4). The MACCE and in-hospital mortality were 7% (n = 10) and 1% (n = 2), respectively. The results were confirmed in a secondary analysis comparing Microplegia with crystalloid cardioplegic solution (n = 271). Conclusion: The use of MiECC with Microplegia in urgent CABG surgery is feasible and safe and provides a straight-forward intraoperative setting. Therefore, it can also be considered to retain the benefits of MiECC in urgent CABG surgery. Full article

RNS60 is a physically modified saline solution hypothesized to contain oxygen nanobubbles. It has been reported to reduce ischemia/reperfusion injury in a pig model of acute myocardial infarction. We investigated the effects of RNS60 during cardiac hypoxia in mice and as an additive to cardioplegic solution in rat hearts. ApoE^−/−LDLr^−/− mice were treated by intravenous injection of RNS60 or saline as a control while monitoring the ECG and post-hypoxic serum release of troponin T and creatine kinase activity. Hearts infused with Custodiol containing 10% RNS60 or saline as the control were subjected to 4 h of 4 °C preservation, followed by an assessment of myocardial metabolites, purine release, and mechanical function. RNS60 attenuated changes in the ECG STU area during hypoxia, while the troponin T concentration and creatine kinase activity were significantly higher in the serum of the controls. During reperfusion after 4 h of cold ischemia, the Custodiol/RNS60-treated hearts had about 30% lower LVEDP and better dp/dt_max and dp/dt_min together with a decreased release of purine catabolites vs. the controls. The myocardial ATP, total adenine nucleotides, and phosphocreatine concentrations were higher in the RNS60-treated hearts. This study indicates that RNS60 enhances cardioprotection in experimental myocardial hypoxia and under conditions of cardioplegic arrest. Improved cardiac energetics are involved in the protective effect, but complete elucidation of the mechanism requires further study. Full article

The race for an ideal cardioplegic solution has remained enthusiastic since the beginning of the modern cardiac surgery era. The Bretschneider solution, belonging to the “intracellular cardioplegic” group, is safe and practical in myocardial protection during ischemic time. Over time, some particular concerns have arisen regarding the effects on cardiac metabolism and postoperative myocardial functioning. This paper reviews the most important standpoints in terms of theoretical and practical analyses. Full article

Background and Objectives: The cardioplegic arrest of the heart during cardiosurgical procedures is the crucial element of a cardioprotection strategy. Numerous clinical trials compare different cardioplegic solutions and cardioprotective protocols, but a relatively small number of papers apply to in vitro conditions using cultured cells. This work aimed to analyze whether it is possible to use the rat heart myocardium cells as an in vitro model to study the protective properties of St. Thomas cardioplegia (ST2C). Methods: The rat heart myocardium cells-H9C2 were incubated with cold cardioplegia for up to 24 h. After incubation, we determined: viability, confluency, and cell size, the thiol groups’ level by modifying Ellman’s method, Ki67, and Proliferating Cell Nuclear Antigen expression (PCNA). The impact on cells’ morphology was visualized by the ultrastructural (TEM) study and holotomograpic 3D imaging. Results: The viability and confluency analysis demonstrated that the safest exposure to ST2C, should not exceed 4h. An increased expression of Ki67 antigen and PCNA was observed. TEM and 3D imaging studies revealed vacuolization after the longest period of exposure (24). Conclusions: According to obtained results, we conclude that STC can play a protective role in cardiac surgery during heart arrest. Full article

Cardiac surgeries have been improved by accompanying developing cardioplegia solutions. However, the cardioplegia application presents an ongoing challenge with a view of a sufficiently restored cardiac function. In this review, we focus on the cardioplegia-induced mechanism and summarize the findings of studies undertaken to improve cardioprotective strategies. Currently, and somewhat surprisingly, relatively little is known about cardiac electrolyte regulation through channel physiology. We hope that an improved understanding of the electrolyte transport through ion channels/transporters and modulations of water channel aquaporins will provide an insight into cardiac channel physiology and a channel-based cardiac pathology of a cardiochannelopathy. Full article

A complete and prompt cardiac arrest using a cold cardioplegic solution is routinely used in heart transplantation to protect the graft function. However, warm ischemic time is still inevitable during the procedure to isolate donor hearts in the clinical setting. Our knowledge of the mechanism changes prevented by cold storage, and how warm ischemia damages donor hearts, is extremely poor. The potential consequences of this inevitable warm ischemic time to grafts, and the underlying potential protective mechanism of prompt graft cooling, have been studied in order to explore an advanced graft protection strategy. To this end, a surgical procedure, including 10–15 min warm ischemic time during procurement, was performed in mouse models to mimic the clinical situation (Group I), and compared to a group of mice that had the procurement performed with prompt cooling procedures (Group II). The myocardial morphologic changes (including ultrastructure) were then assessed by electron and optical microscopy after 6 h of cold preservation. Furthermore, syngeneic heart transplantation was performed after 6 h of cold preservation to measure the graft heart function. An electron microscopy showed extensive damage, including hypercontracted myofibers with contraction bands, and damaged mitochondria that released mitochondrial contents in Group I mice, while similar patterns of damage were not observed in the mice from Group II. The results from both the electron microscopy and immunoblotting verified that cardiac mitophagy (protective mitochondrial autophagy) was present in the mice from Group II, but was absent in the mice from Group I. Moreover, the mice from Group II demonstrated faster rebeating times and higher beating scores, as compared to the mice from Group I. The pressure catheter system results indicated that the graft heart function was significantly more improved in the mice from Group II than in those from Group I, as demonstrated by the left ventricle systolic pressure (31.96 ± 6.54 vs. 26.12 ± 8.87 mmHg), the +dp/dt (815.6 ± 215.4 vs. 693.9 ± 153.8 mmHg/s), and the -dp/dt: (492.4 ± 92.98 vs. 418.5 ± 118.9 mmHg/s). In conclusion, the warm ischemic time during the procedure impaired the graft function and destroyed the activation of mitophagy. Thus, appropriate mitophagy activation has emerged as a promising therapeutic target that may be essential for graft protection and functional improvement during heart transplantation. Full article

Despite current advances in perioperative care, intraoperative myocardial protection during cardiac surgery has not kept the same pace. High potassium cardioplegic solutions were introduced in the 1950s, and in the early 1960s they were soon recognized as harmful. Since that time, surgeons have minimized many of the adverse effects by lowering the temperature of the heart, lowering K⁺ concentration, reducing contact K⁺ time, changing the vehicle from a crystalloid solution to whole-blood, adding many pharmacological protectants and modifying reperfusion conditions. Despite these attempts, high potassium remains a suboptimalway to arrest the heart. We briefly review the historical advances and failures of finding alternatives to high potassium, the drawbacks of a prolonged depolarized membrane, altered Ca²⁺ intracellular circuits and heterogeneity in atrial-ventricular K⁺ repolarization during reanimation. Many of these untoward effects may be alleviated by a polarized membrane, and we will discuss the basic science and clinical experience from a number of institutions trialling different alternatives, and our institution with a non-depolarizing adenosine, lidocaine and magnesium (ALM) cardioplegia. The future of polarized arrest is an exciting one and may play an important role in treating the next generation of patients who are older, and sicker with multiple comorbidities and require more complex operations with prolonged cross-clamping times. Full article