Histidine-tryptophan-ketoglutarate Research Articles

Optimizing Myocardial Protection in Minimally Invasive Cardiac Surgeries: A Network Comparison of Del Nido, Histidine-Tryptophan-Ketoglutarate, and Blood Cardioplegia.

Background/Objectives: The optimal choice of cardioplegia solution in minimally invasive cardiac surgeries (MICS) remains debated, as prolonged myocardial protection is essential to avoid interruptions to the surgical flow, which can prolong aortic cross-clamp time and cardiopulmonary bypass time, especially in the constrained surgical field. We conducted a network meta-analysis to evaluate the safety and efficacy of the del Nido (DN), histidine-tryptophan-ketoglutarate (HTK), blood cardioplegia (BC), and St. Thomas' (STH) solutions in MICS. Methods: Medical electronic databases were thoroughly searched without time restrictions, including all types of studies except for study protocols and animal research. The final search was completed in June 2024. Subsequently, a network meta-regression was performed on both primary and secondary endpoints, utilizing R (The R Foundation for Statistical Computing, version 3.6.2) for the analysis. Meta-analyses were carried out using Review Manager software. Results: A total of 15 studies, enrolling 2282 patients, were included in the analysis. None of the comparisons showed statistically significant differences in in-hospital mortality between the four cardioplegia solutions (BC vs. HTK, OR: 3.21, 95% CI: 0.13-80.84; DN vs. HTK, OR: 1.42, 95% CI: 0.28-7.23; STH vs. HTK, OR: 1.25, 95% CI: 0.19-8.20). Conclusions: In this network meta-analysis of cardioplegia solutions in MICS, no significant differences were observed in major clinical outcomes across the solutions. Cardioplegia solutions that provide long-lasting myocardial protection with a single dose, such as DN and HTK, were found to be safely applied in MICS. DN was associated with shorter CPB times and HTK was associated with shorter hospital stays, though these differences may not have clinical implications.

Histidine-trytophan-ketoglutarate cardioplegia reduces inflammatory response and serum levels of myocardial enzymes in newly developed right-thoracotomy rat model

The objective of this research was to establish a rat model for cardiopulmonary bypass (CPB) with cardiac arrest and resuscitation that is both practical and economical and simulates clinical cardiac surgery. Concurrently, the study aimed to evaluate the myocardial protective effects conferred by histidine–tryptophan–ketoglutarate (HTK) cardioplegia. Thirty rats were randomly assigned to three groups: the histidine–tryptophan–ketoglutarate (HTK), 4:1 blood cardioplegia (BC) and del Nido cardioplegia (DN) groups. The cardiopulmonary bypass (CPB) procedure was implemented and sustained for a duration of one hour. Subsequent to the cessation of CPB, the rats were subjected to monitoring and observation for an additional two hours. Following this observation period, the heart and blood samples were procured for subsequent analysis. During CPB, the average hematocrit level was significantly below the typical physiological range (P < 0.001). Histopathological scores were notably lower in the HTK group in contrast to the BC group (P < 0.001) or the DN group (P < 0.001). At 2 h after weaning off CPB, the levels of CK and CKMB in the DN and BC groups were notably elevated compared to the HTK group (P < 0.001). The levels of IL-6 and TNF-α proteins were notably increased in all three groups (P < 0.001), with the BC and DN groups showing higher increases compared to the HTK group (P < 0.001). This compact animal model of cardiopulmonary bypass (CPB) with cardiac arrest and resuscitation might allow for both the study of myocardial ischemia-reperfusion injury as well as cardioprotective strategies. HTK cardioplegia could reduce inflammatory response and serum levels of myocardial enzymes in this newly developed right thoracotomy rat model.

The Impact of Hyponatremia in Aortic Valve Surgery Using Histidine–Tryptophan–Ketoglutarate Cardioplegia

The Impact of Hyponatremia in Aortic Valve Surgery Using Histidine–Tryptophan–Ketoglutarate Cardioplegia

Added Value of Histological Evaluation of Muscle Biopsies in Porcine Vascularized Composite Allografts.

Background: Machine perfusion (MP) offers extended preservation of vascularized complex allografts (VCA), but the diagnostic value of histology using hematoxylin and eosin (H&E) in detecting ischemia-reperfusion injury (IRI) in muscle cells remains unclear. This study aims to document the application of the Histology Injury Severity Score (HISS) and to assess whether additional staining for nicotinamide adenine dinucleotide (NADH) and membrane attack complex (MAC) improves IRI detection in a porcine limb replantation model. Methods: The forelimbs of 16 Dutch Landrace pigs were amputated and preserved for 24 h using hypothermic MP (n = 8) with Histidine-Tryptophan-Ketoglutarate (HTK) or for 4 h with SCS (n = 8) before heterotopic replantation and 7 days of follow-up. Muscle damage was assessed via biochemical markers and light microscopy using H&E, NADH, and MAC at baseline, post-intervention, and post-operative day (POD) 1, 3, and 7 timepoints, using the HISS and a self-developed NADH and MAC score. Results: H&E effectively identified damaged muscle fibers and contributed to IRI assessment in porcine limbs (p < 0.05). The highest HISS was measured on POD 3 between MP (4.9) and SCS (3.5) (p = 0.029). NADH scores of both preservation groups varied over the 7-day follow-up and were statistically insignificant compared with baseline measurements (p > 0.05). MAC revealed no to minimal necrotic tissue across the different timepoints. Conclusions: This study documents the application of the HISS with H&E to detect IRI in muscle fibers. NADH and MAC showed no significant added diagnostic utility. The 24 h MP showed similar muscle alterations using the HISS compared to that of the 4 h SCS after a 7-day follow up.

Mitigating Cold Ischemic Injury: HTK, UW and IGL-2 Solution's Role in Enhancing Antioxidant Defence and Reducing Inflammation in Steatotic Livers.

Liver transplantation remains the only definitive treatment for end-stage liver diseases. However, the increasing prevalence of fatty liver disease among potential donors exacerbates the shortage of suitable organs. This study evaluates the efficacy of the preservation solution Institut Georges Lopez-2 (IGL-2) compared to Histidine-Tryptophan-Ketoglutarate (HTK) and University of Wisconsin (UW) preservation solutions in mitigating ischemia-reperfusion injury (IRI) in steatotic livers. Using Zucker Obese rat livers, we assessed the impact of 24-h static cold storage (SCS) with each solution on transaminase release, glutathione redox balance, antioxidant enzyme activity, lipoperoxidation, and inflammation markers. IGL-2 and UW solutions demonstrated reduced transaminase and lactate levels compared to HTK, indicating better preservation of liver integrity. IGL-2 maintained a higher reduced glutathione/oxidized glutathione (GSH/GSSG) ratio, suggesting more effective management of oxidative stress. Antioxidant enzyme activities catalase, superoxide dismutase, and glutathione peroxidase (CAT, SOD, GPX) were higher in IGL-2 preserved livers, contributing to decreased oxidative damage. Lipid peroxidation markers and inflammatory markers were lower in IGL-2 than in HTK, indicating reduced oxidative stress and inflammation. Additionally, improved mitochondrial function was observed in the IGL-2 group, correlating with reduced reactive oxygen species (ROS) production and lipid peroxidation. These findings suggest that IGL-2 offers superior preservation of liver viability, reduces oxidative stress, and minimizes inflammation compared to HTK and UW solutions. By maintaining a higher ratio of reduced glutathione and antioxidant enzyme activity, IGL-2 effectively mitigates the harmful effects of ischemia-reperfusion injury. The reduced lipid peroxidation and inflammation in the IGL-2 group further underscore its potential in improving liver transplant outcomes. These results highlight the importance of optimizing preservation solutions to enhance the viability and functionality of donor organs, potentially expanding the donor pool and improving the success rates of liver transplantation. Future research should focus on refining preservation techniques and exploring additional protective agents to further improve organ preservation and transplant outcomes.

Prolongation of the Time Window From Traumatic Limb Amputation to Replantation From 6 to 33 Hours Using Ex Vivo Limb Perfusion.

Continuous extracorporeal perfusion (ECP), or machine perfusion, holds promise for prolonged skeletal muscle preservation in limb ischemia-reperfusion injury. This study aimed to extend the amputation-to-replantation time window from currently 6 hours to 33 hours using a 24-hour ECP approach. Six large white pigs underwent surgical forelimb amputation under general anesthesia. After amputation, limbs were kept for 9 hours at room temperature and then perfused by 24-hour ECP with a modified histidine-tryptophan-ketoglutarate (HTK) solution. After ECP, limbs were orthotopically replanted and perfused in vivo for 12 hours. Clinical data, blood, and tissue samples were collected and analyzed. All 6 forelimbs could be successfully replanted and in vivo reperfused for 12 hours after 9 hours of room temperature ischemia followed by 24 hours ECP. Adequate limb perfusion was observed after replantation as shown by thermography and laser Doppler imaging. All pigs survived without severe organ failure, and no significant increase in inflammatory cytokines was found. Macroscopy and histology showed marked interstitial muscular edema of the limbs, whereas myofiber necrosis was not evident, implying the preservation of muscular integrity. The use of a 24-hour ECP has successfully extended limb preservation to 33 hours. The modified histidine-tryptophan-ketoglutarate perfusate demonstrated its ability for muscle protection. This innovative approach not only facilitates limb replantation after combat injuries, surmounting geographical barriers, but also broadens the prospects for well-matched limb allotransplants across countries and continents.

Low Calcium-High Magnesium Krebs-Henseleit Solution Combined with Adenosine and Lidocaine Improved Rat Aortic Function and Structure Following Cold Preservation.

Background and objectives: The main problem of vascular preservation is the maintenance of vessel graft quality and function following extended storage. Conventional preservation solutions such as histidine-tryptophan-ketoglutarate (HTK) solution, Phosphate-Buffer Solution (PBS), or sodium chloride 0.9% has been shown to be inadequate in preserving vascular physiological function after 3 days of cold storage. This study aimed to evaluate whether adenosine and lidocaine (AL) in a modified Krebs-Henseleit (KH) solution can preserve the function and histological structure of rat aortic rings after 6 days. Materials and Methods: Thirty-five aortic rings from male Wistar rats (200-300 g) were harvested and immediately immersed in one of the assigned cold preservation solutions: standard KH, modified KH (mod KH) with lower calcium (Ca2+) and higher magnesium content (Mg2+) with or without adenosine and lidocaine (mod KH-AL), and modified KH with AL, insulin, and melatonin (Mod KH-ALMI). The contraction and relaxation function of the aortic rings were examined using an isometric force transducer after 6 days of cold preservation. Hematoxylin and eosin staining were used to analyze the rings' histological structure. Results: Vascular contraction and relaxation functions were severely affected after a 6-day cold storage period in standard KH. Modifying the KH solution by reducing the Ca2+ and increasing the Mg2+ levels greatly recovered the vessel functions. The addition of AL or ALMI to the modified KH did not further recover vascular contractility. However, only the addition of AL to the modified KH increased the ACh-induced relaxation at 6 days when compared to the conventional KH, suggesting that endothelium preservation is improved. From histological analysis, it was found that the addition of AL but not ALMI further improved the endothelial lining and the structure of the elastic membrane layers of the preserved vessels after 6 days of cold preservation. Conclusions: The addition of AL to low calcium-high magnesium KH solution significantly enhanced endothelial preservation and improved endothelial-induced relaxation of preserved vessels after 6 days of cold storage.

Histidine-Tryptophan-Ketoglutarate Cardioplegia Yields Different Results in Aortic Valve Surgery Depending on Patient Gender: A Pilot Study.

Histidine-tryptophan-ketoglutarate (HTK) cardioplegia induces cardiac arrest through membrane hyperpolarization. Aortic valve pathology leads to pathophysiological changes in left ventricular vascularization that may prevent adequate cardioplegic distribution. The objective of the study was to ascertain whether the use of Bretschneider cardioplegia in aortic valve surgery yields different outcomes for male and female patients. Our study compares the perioperative data of 300 adult patients who underwent aortic valve replacement between June 2023 and June 2024 at the Emergency Cardiac Disease and Transplant Institute, Tîrgu Mures, Romania. Concomitant procedures, age under 18 years, retrograde or combined cardioplegia, and emergency surgery were excluded. The main outcome was operative mortality, and secondary outcomes were postoperative complications and paraclinical data such as ejection fraction and cardiac enzymes. Male patients comprised 190 (62%) of the sample. The most common age group was 61-70 years in both groups. The mortality rate was 6 (5.4%) for women compared to 9 (4.7%) for men. Preoperative left ventricular ejection fraction was the primary covariate determining 30-day postoperative mortality. Left ventricular ejection fraction decreased by 2.2% in men and 1.1% in women 30 days after surgery. The myocardial adaptation to aortic valve pathology exhibits gender-specific differences. However, the utilization of HTK cardioplegia obviates this disparity.

Comparison Between Histidine-Tryptophan-Ketoglutarate Cardioplegia and Cold Blood Cardioplegia for Myocardial Protection in Tetralogy of Fallot Patients Undergoing Surgical Repair: A Randomized Clinical Trial

ObjectivesThis study was conducted to compare the efficacy of histidine-tryptophan-ketoglutarate (HTK) cardioplegia and cold blood cardioplegia (CBC), especially for postoperative right ventricle (RV) function after Tetralogy of Fallot (TOF) repair. DesignRandomized, double-blinded, parallel group, controlled, clinical trial. SettingAin Shams University Hospitals.) ParticipantsA total of 100 children (1-5 years-old) scheduled for TOF repair. InterventionsPatients were allocated (double blinded one: one allocation ratio), to either HTK Group that received HTK cardioplegia (30 ml/kg by antegrade route) or CBC Group that received cold blood cardioplegia with blood to Ringer solution (4:1) in volume of 20 ml/kg. Measurements and Main ResultsThe HTK group showed a statistically significant reduction of the vasoactive inotropic score on admission to pediatric intensive care unit (13.0±4.1) in comparison to CBC (15.5±5.4) with P-value of 0.011 but after 24 hours Vasoactive-Inotropic Score was comparable. Lactate level during the first 24 hours in HTK group (6.2±0.7) mmol/l and (6.9±0.4) mmol/l in CBC group with P-value < 0.0001. Serial troponin measurements were lower in the HTK group (1.49 ± 0.45) in comparison to the CBC group (1.69 ± 0.18) with P-value of 0.005 at the first 72 hours postoperatively. Postoperative echocardiographic assessment of RV function by mean of tricuspid annular plane systolic excursion and myocardial performance index were better in HTK than CBC (P-value<0.05). ConclusionsHTK cardioplegia may offer better cardiac protection to pediatric patients undergoing TOF repair than our institutional standard CBC with better recovery for the hypertrophic RV.

The Potential Neurological Impact of Intraoperative Hyponatremia Using Histidine-Tryptophan-Ketoglutarate Cardioplegia Infusion in Adult Cardiac Surgery.

Background and Objectives: The relationship between histidine-tryptophan-ketoglutarate (HTK)-induced hyponatremia and brain injury in adult cardiac surgery patients is unclear. This study analyzed postoperative neurological outcomes after intraoperative HTK cardioplegia infusion. Materials and Methods: A prospective cohort study was conducted on 60 adult patients who underwent cardiac surgery with cardiopulmonary bypass. Of these patients, 13 and 47 received HTK infusion and conventional hyperkalemic cardioplegia, respectively. The patients' baseline characteristics, intraoperative data, brain injury markers, Mini-Mental State Examination (MMSE) scores, and quantitative electroencephalography (qEEG) data were collected. Electrolyte changes during cardiopulmonary bypass, the degree of hyponatremia, and any associated brain insults were evaluated. Results: The HTK group presented with acute hyponatremia during cardiopulmonary bypass, which was intraoperatively corrected through ultrafiltration and normal saline administration. Postoperative sodium levels were higher in the HTK group than in the conventional cardioplegia group. The change in neuron-specific enolase levels after cardiopulmonary bypass was significantly higher in the HTK group (p = 0.043). The changes showed no significant differences using case-control matching. qEEG analysis revealed a significant increase in relative delta power in the HTK group on postoperative day (POD) 7 (p = 0.018); however, no significant changes were noted on POD 60. The MMSE scores were not significantly different between the two groups on POD 7 and POD 60. Conclusions: HTK-induced acute hyponatremia and rapid correction with normal saline during adult cardiac surgeries were associated with a potential short-term but not long-term neurological impact. Further studies are required to determine the necessity of correction for HTK-induced hyponatremia.

Transcriptomic Changes in the Myocardium and Coronary Artery of Donation after Circulatory Death Hearts following Ex Vivo Machine Perfusion.

Donation after circulatory death (DCD) hearts are predominantly maintained by normothermic blood perfusion (NBP). Nevertheless, it was shown that hypothermic crystalloid perfusion (HCP) is superior to blood perfusion to recondition left ventricular (LV) contractility. However, transcriptomic changes in the myocardium and coronary artery in DCD hearts after HCP and NBP have not been investigated yet. In a pig model, DCD hearts were harvested and maintained for 4 h by NBP (DCD-BP group, N = 8) or HCP with oxygenated histidine-tryptophane-ketoglutarate (HTK) solution (DCD-HTK, N = 8) followed by reperfusion with fresh blood for 2 h. In the DCD group (N = 8), hearts underwent reperfusion immediately after procurement. In the control group (N = 7), no circulatory death was induced. We performed transcriptomics from LV myocardial and left anterior descending (LAD) samples using microarrays (25,470 genes). We applied the Boruta algorithm for variable selection to identify relevant genes. In the DCD-BP group, compared to DCD, six genes were regulated in the myocardium and 1915 genes were regulated in the LAD. In the DCD-HTK group, 259 genes were downregulated in the myocardium and 27 in the LAD; and 52 genes were upregulated in the myocardium and 765 in the LAD, compared to the DCD group. We identified seven genes of relevance for group identification: ITPRIP, G3BP1, ARRDC3, XPO6, NOP2, SPTSSA, and IL-6. NBP resulted in the upregulation of genes involved in mitochondrial calcium accumulation and ROS production, the reduction in microvascular endothelial sprouting, and inflammation. HCP resulted in the downregulation of genes involved in NF-κB-, STAT3-, and SASP-activation and inflammation.

Histidine tryptophan ketoglutarate (HTK) versus University of Wisconsin (UW) for Liver transplant: A Quasi-experimental study

Histidine tryptophan ketoglutarate (HTK) versus University of Wisconsin (UW) for Liver transplant: A Quasi-experimental study

Post-reperfusion syndrome among liver transplant recipients in HTK (Histidine- Tryptophan- Ketoglutarate) versus UW (University of Wisconsin) preservation solution

Post-reperfusion syndrome among liver transplant recipients in HTK (Histidine- Tryptophan- Ketoglutarate) versus UW (University of Wisconsin) preservation solution

Efficacy and short-term outcomes of myocardial protection using single-dose histidine-tryptophan-ketoglutarate cardioplegia during aortic root surgery with different duration of myocardial ischemia

Objective: To explore the efficacy of myocardial protection with single-dose histidine-tryptophan-ketoglutarate (HTK) cardioplegia during aortic root operation, and the correlation between short-term clinical outcomes and duration of myocardial ischemia. Methods: The data of clinical cases undergoing myocardial protection with single-dose HTK cardioplegia during aortic root operation from January 2018 to December 2022 were retrospectively reviewed. Patients were divided into conventional HTK cardioplegia group (<3 h) and prolonged HTK cardioplegia group (≥3 h) according to duration of intraoperative myocardial ischemia. A 1∶1 propensity score matching was performed and the correlations between duration of myocardial ischemia and postoperative short-term outcomes (30-day mortality, readmission, mechanical circulation support and renal insufficiency) were analyzed. Results: A total of 282 patients were included in the final analysis, with 210 cases in the conventional HTK cardioplegia group and 72 cases inthe prolonged HTK cardioplegia group before matching. After matching, there were 64 cases (53 males and 11 females) in the conventional HTK cardioplegia group, with a mean age of (49.4±14.2) years. The prolonged HTK cardioplegia group had 64 cases (55 males and 9 females), with a mean age of (50.5±12.3) years. Higher sensitivity troponin [12 h: 10.1 (4.6, 18.7) μg/Lvs 4.1(2.2, 8.6) μg/L, P=0.002; 24 h: 7.7 (4.5, 19.0) μg/L vs 4.8 (2.2, 11.9) μg/L, P=0.025] and creatine kinase isoenzyme[12 h: 46.3 (28.1, 62.4) μg/L vs 20.7(14.1, 32.9) μg/L, P<0.001; 24 h: 26.3(13.4, 49.2) μg/L vs 14.5 (10.1, 33.5)μg/L, P=0.011] after surgery was detected in prolonged HTK cardioplegia group. Comparisons of other primary and secondary endpoint events showed no significant differences between the two groups (all P>0.05). Multivariate binary logistic regression showed that duration of myocardial ischemia had no significant effect on postoperative 30-day mortality (OR=1.255, 95%CI: 0.500-3.148, P=0.629), 30-day readmission (OR=0.378, 95%CI: 0.069-2.065, P=0.261) and mechanical circulation support (OR=0.991, 95%CI: 0.331-2.970, P=0.998). Conclusion: During aortic root surgery, single-dose HTK cardioplegia may provide satisfactory myocardial protection, and there was no significant correlation between duration of myocardial ischemia and short-term clinical outcomes.

Association of cardiac preservation solution with short-term outcomes after heart transplantation.

There is wide variability in the practice of cardiac preservation for heart transplantation. Prior reports suggest that the type of solution may be linked with a reduced incidence of posttransplantation complications. Adult (≥18 years old) heart recipients who underwent transplantation between 2015 and 2021 in the United States were examined. Recipients were stratified by solution utilized for their grafts at the time of recovery: University of Wisconsin, histidine-tryptophan-ketoglutarate (HTK), or Celsior solution. The primary endpoint was a composite of 30-day mortality, primary graft dysfunction, or re-transplantation. Risk adjustment was performed for the recipient, donor, and procedural characteristics using regression modeling. Among 16 884 recipients, the group distribution was University of Wisconsin solution 53%, HTK 22%, Celsior solution 15%, and other 10%. The observed incidence of the composite endpoint (University of Wisconsin solution = 3.6%, HTK = 4.0%, Celsior solution = 3.7%, P = 0.301) and 1-year survival (University of Wisconsin solution = 91.7%, HTK = 91.3%, Celsior solution = 91.7%, log-rank P = 0.777) were similar between groups. After adjustment, HTK was associated with a higher risk of the composite endpoint [odds ratio (OR) 1.249, 95% confidence interval (CI) 1.019-1.525, P = 0.030] in reference to University of Wisconsin solution. This association was substantially increased among recipients with ischemic periods of greater than 4 h (OR 1.817, 95% CI 1.188-2.730, P = 0.005). The risks were similar between University of Wisconsin solution and Celsior solution (P = 0.454). The use of the histidine-tryptophan-ketoglutarate solution during cold static storage for cardiac preservation is associated with increased rates of early mortality or primary graft dysfunction. Clinician discretion should guide its use, especially when prolonged ischemic times (>4 h) are anticipated.

Del Nido cardioplegia or potassium induces Nrf2 and protects cardiomyocytes against oxidative stress.

Open heart surgery is often an unavoidable procedure for the treatment of coronary artery disease. The procedure-associated reperfusion injury affects postoperative cardiac performance and long-term outcomes. We addressed here whether cardioplegia essential for cardiopulmonary bypass surgery activates Nrf2, a transcription factor regulating the expression of antioxidant and detoxification genes. With commonly used cardioplegic solutions, high K+, low K+, Del Nido (DN), histidine-tryptophan-ketoglutarate (HTK), and Celsior (CS), we found that DN caused a significant increase of Nrf2 protein in AC16 human cardiomyocytes. Tracing the ingredients in DN led to the discovery of KCl at the concentration of 20-60 mM capable of significant Nrf2 protein induction. The antioxidant response element (ARE) luciferase reporter assays confirmed Nrf2 activation by DN or KCl. Transcriptomic profiling using RNA-seq revealed that oxidation-reduction as a main gene ontology group affected by KCl. KCl indeed elevated the expression of classical Nrf2 downstream targets, including TXNRD1, AKR1C, AKR1B1, SRXN1, and G6PD. DN or KCl-induced Nrf2 elevation is Ca2+ concentration dependent. We found that KCl decreased Nrf2 protein ubiquitination and extended the half-life of Nrf2 from 17.8 to 25.1 mins. Knocking out Keap1 blocked Nrf2 induction by K+. Nrf2 induction by DN or KCl correlates with the protection against reactive oxygen species generation or loss of viability by H2O2 treatment. Our data support that high K+ concentration in DN cardioplegic solution can induce Nrf2 protein and protect cardiomyocytes against oxidative damage.NEW & NOTEWORTHY Open heart surgery is often an unavoidable procedure for the treatment of coronary artery disease. The procedure-associated reperfusion injury affects postoperative cardiac performance and long-term outcomes. We report here that Del Nido cardioplegic solution or potassium is an effective inducer of Nrf2 transcription factor, which controls the antioxidant and detoxification response. This indicates that Del Nido solution is not only essential for open heart surgery but also exhibits cardiac protective activity.

A propensity score matched analysis of liver transplantation outcomes in the setting of preservation solution shortage

The recent shortage of the University of Wisconsin (UW) solution prompted increased utilization of histidine-tryptophan-ketoglutarate (HTK) solution for liver graft preservation. This contemporary study analyzed deceased donor liver transplant outcomes following preservation with HTK vs UW. Patients receiving deceased donor liver transplantations between January 1, 2019, and June 30, 2022, were retrospectively identified utilizing the Organ Procurement and Transplant Network database, stratified by preservation with HTK vs UW, and a propensity score matching analysis was performed. Outcomes assessed included rates of primary nonfunction, graft survival, and patient survival. There were 4447 patients in each cohort. Primary nonfunction occurred in 60 (1.35%) patients in the HTK group vs 25 (0.54%) in the UW group (P < .001). HTK was associated with lower 90-day graft survival (94.39% vs 96.09%; P < .001) and 90-day patient survival (95.97% vs 97.38%; P = .001). Unmatched donation after cardiac death-specific analysis of HTK vs UW demonstrated respective rates of primary nonfunction of 1.63% vs 0.82% (P = .20), 90-day graft survival of 92.50% vs 95.29% (P = .069), and 90-day patient survival of 93.90% vs 96.35% (P = .077). These results suggest that HTK may not be an equivalent preservation solution for deceased donor liver transplantation.

N-terminal pro-B type natriuretic peptide as a predictor for myocardial preservation in cases of isolated severe Aortic stenosis

Background Myocardial hypertrophy is a common pathologic finding in the natural history of severe aortic stenosis. A hypertrophied myocardium predisposes the patient to decreased tolerance to ischemia and increased reperfusion injury, myocardial protection is of utmost importance in patients undergoing aortic valve replacement (AVR) for severe aortic valve stenosis. Myocardial protection techniques during cardiac arrest have been extensively investigated in the clinical setting of coronary revascularization. However, fewer studies have been carried out on patients affected by left ventricular (LV) hypertrophy, where the choice of type, and temperature of cardioplegia remains controversial. Aim The study investigates preoperative N-terminal pro-B type natriuretic peptide (NT pro-BNP), its relation to Troponin I levels, and whether it can predict a preferred cardioplegic solution by comparing the short-term outcomes of the two commonly used blood and Histidine-Tryptophan-Ketoglutarate (HTK) cardioplegic solutions in patients undergoing aortic valve replacement for severe aortic stenosis. Patients and methods A total of 72 patients will be randomly allocated into two groups; group (A=36) received HTK solution, and group (B=36) received blood cardioplegia. All anesthesia protocols are unified among all patients. All surgical procedures were conducted on a cardioplegic arrested heart via standard median sternotomy, utilizing full Cardiopulmonary bypass (CPB) via aorto-atrial cannulation and LV venting through a left atrial catheter under moderate hypothermia (28–32°C) by topical cooling. Results There was no statistically significant difference found between group A and group B regarding post-operative ejection fraction (EF) and newly developed postoperative Regional wall motion abnormalities (RWMA). There was no statistically significant difference found between group A and group B regarding the percentage of patients with atrial fibrillation, ventilation hours, and exploration while there was a statistically significant increase in troponin, I level in group B than group A. There was a statistically significant negative correlation between NT pro-BNP preoperative and aortic valve area (AVA) and also with ejection fraction preoperative while there was a statistically significant positive correlation found between NT pro-BNP and troponin I preoperative and postoperative. Conclusion HTK solution and Blood cardioplegia both offer sufficient protection for the myocardium. NT pro-BNP serves as a sensitive indicator for predicting the results and effectiveness of different cardioplegia types

Deceased Donor Flush Volume Similar for Histidine-Tryptophan-Ketoglutarate and University of Wisconsin at a Single US Organ Procurement Organization: Adult and Pediatric Data

Histidine-tryptophan-ketoglutarate (HTK) and University of Wisconsin (UW) solutions are the two primary solid-organ preservation solutions used in the United States (>95%), but flush volumes vary markedly by region and center. This study analyzes data from a single organ procurement organization (OPO) to determine the actual clinical flush volumes used for HTK and UW for liver and pancreas grafts. All procurements at Indiana Donor Network were analyzed (2016-2020), and data were extracted from the on-site records. Variables included procuring center, solution, volumes, and vessels flushed. Brand and generic versions were considered equivalent. No clinical transplant outcomes were available. Data were analyzed from 875 liver and 192 pancreas procurements by over 70 U.S. centers representing 10 of 11 UNOS regions. The large majority of liver grafts were preserved with HTK (n=810, 93%; UW n=93, 7%). All liver donors received an aortic flush (100%), while portal vein flush was 14% in-situ and 88% back table. For liver grafts, the median volume of infused solution was less for HTK when compared to UW (4225mL vs 5500mL, p=0.04). For pancreas procurement, 100% received aortic flush of the graft, with median HTK and UW volumes being equivalent (3000mL; p=0.85). Pediatric organs were flushed with markedly higher weight-based volumes. Flush volumes for HTK and UW are similar at one midwestern OPO, with data comprised of procurements performed by centers from across the U.S. These data demonstrate that low-volume HTK flush is commonly used, and this practice may be considered as a cost-saving measure.

Protective Effects of Different Hypothermal Preservation Solutions on Structure and Function of Isolated Rat Arteries.

With the increasing application of vascular reconstruction in surgical procedures, allogeneic vessels are becoming more popular in clinical practice due to their abundant sources, precise diameter matching, improved histocompatibility, and higher long-term patency rate. This study aimed to investigate the protective effect of various preservation solutions on the function and structure of the isolated rat abdominal aorta preserved under hypothermal conditions. The study utilized a total of 150 Sprague-Dawley (SD) rats, with 144 rats allocated to the experimental groups and 6 rats allocated to the control groups. The abdominal aorta of the rats was chosen as the subject of our research. The aorta in the experimental groups were randomly assigned to 4 groups: University of Wisconsin (UW) solution group, histidine-tryptophan-ketoglutarate (HTK) solution group, normal saline (NS) group, and sodium lactate Ringer's solution (RS) group. Samples were subjected to examination after preservation periods of 1 day, 3 days, 5 days, 7 days, 14 days, 30 days, and 90 days. Evaluation of vascular physiological function involved detecting and assessing vasoconstriction ability and measuring cell viability through the MTT test. Evaluation of the vascular wall structure involved tension tolerance tests and pathological staining. The pathogen-positive rate in the HTK group and NS group at 1 month was 16.7%. Regarding the vascular skeleton structure, both the UW group and HTK group exhibited intact structures after 2 weeks of preservation, with slightly edematous collagen and elastic fibers, which was significantly better than that of the NS group and RS group. In terms of cell activity and contractile function, all preservation groups showed similar effects within 2 weeks. However, after 2 weeks, the UW group showed the most favorable preservation effect (P<0.05). In terms of vascular tension, different groups exhibited similar effects within 1 week. However, after 2 weeks, the UW group showed the best preservation effect (P<0.05). All 4 types of preservation solution had a preservation effect on the structure and function of isolated blood vessels during short-term hypothermal preservation. However, after 2-week preservation, the UW solution was found to be the most suitable solution for the preservation of blood vessels.