Influence of cardioplegic solution on incidence of acute kidney injury after coronary artery bypass surgery procedure: del Nido cardioplegia versus Histidine-Tryptophan-Ketoglutarate solution: Insight of kidney disease improving global outcomes criteria.

INTRODUCTION: We set out to investigate whether the use of Histidine-Tryptophan-Ketoglutarate (HTK) solution or del Nido cardioplegia is linked to an increased incidence of postoperative acute kidney injury (AKI) in patients undergoing coronary artery bypass surgery (CABG). METHODS: A retrospective study was carried out at our center, with a total of 478 patients included in the analysis. Among them, 268 patients were administered the del Nido solution (DN) while 210 patients received the HTK solution. The primary focus of this study was to assess the occurrence of postoperative AKI and the need for renal replacement therapy (RRT). Multivariable logistic regression was used to examine the relationship between the type of cardioplegia used and adverse kidney outcomes. Additionally, serum levels of sodium, potassium, and ionized calcium were monitored during cardiopulmonary bypass (CPB). RESULTS: The incidence of AKI was significantly higher in the HTK group compared to the DN group [(48/220 (21.81%) vs. 24/186 (12.90%), p = .049], although the rate of RRT did not show a statistically significant difference (9/48, 18.75% vs. 6/24, 25%, p = .538). Multivariate logistic regression analysis revealed that HTK was a significant risk factor for AKI. Furthermore, serum sodium and calcium levels were found to decrease following HTK cardioplegic infusion. Conclusion: Our study provides compelling evidence of the impact of cardioplegic solutions on postoperative AKI rates. It underscores the importance of optimizing cardiac arrest protocols. These findings warrant further prospective investigations into the influence of cardioplegic solutions on electrolyte imbalances and postoperative AKI rates.

Nucleotide metabolism during experimental preservation for transplantation with Transmedium Transplant Fluid (TTF) in comparison to Histidine-Tryptophan-Ketoglutarate (HTK).

Organ preservation solutions are essential to diminish ischemic/hypoxic injury during cold storage and to improve graft survival. In our experiments, we investigated novel solutions that target such mechanisms as Transmedium Transplant Fluid (TTF) in comparison to PlegiStore solution (HTK). Rat hearts were infused with TTF or HTK and then subjected to 4 hours of 4 °C preservation followed by 25 minutes of reperfusion in the Langendorff system. Assessment of purine release from the heart, mechanical function, and cardiac nucleotide content in the heart homogenates was done. A significant increase in the uric acid, hypoxanthine, inosine, and total purine metabolite concentrations were observed in the HTK hearts when compared to TTF. The TTF group had lower left ventricular systolic pressure and left ventricular end-diastolic pressure when compared to the HTK. Left ventricular diastolic pressure, minimal dp/dt, and maximal dp/dt in both groups were similar. The concentration of ADP in the heart homogenates of the HTK group was increased when compared to the TTF group. ATP and GTP concentration showed a tendency to increase in the homogenates of TTF hearts when NAD, AMP, GDP, GMP, and ADPR were similar in both groups of rats. TTF provided enhanced cardioprotection as evidenced by inhibiting the purine nucleotide metabolites released from the rat hearts during reperfusion and enhanced systolic and diastolic mechanical function recovery. In particular, better preservation of GTP and ATP concentrations may translate into enhanced protection of endothelium and the cytoskeleton, which are not adequately protected with current preservation techniques.

Histidine-tryptophan-ketoglutarate solution versus multidose cardioplegia for myocardial protection in cardiac surgeries: a systematic review and meta-analysis.

BACKGROUND: Surgical procedures in the heart requires protection of the heart from ischemia-reperfusion injury. Cardioplegia is the primary myocardial protective method in use. Histidine-tryptophan-ketoglutarate (HTK) solution is an intracellular cardioplegic solution that was initially used to preserve organs for transplantation. METHODS: A systematic electronic search was conducted in July 2021, in four databases; PubMed, Scopus, Web of Science, and Cochrane Library for eligible randomized controlled trials. The results were screened and the eligible trials were identified. Thereafter, the relevant data were extracted and pooled as mean difference or risk ratio, and 95% confidence interval in an inverse variance method using RevMan software. RESULTS: This review included 12 trials (n = 1327). HTK solution has resulted significantly in shorter intensive care unit stay (MD = - 0.09; 95% CI [- 0.15, - 0.03], p = 0.006), and shorter hospital stay (MD = - 0.51; 95% CI [- 0.71, - 0.31], p < 0.00001). Moreover, the patients who received the HTK solution had significantly lower levels of creatine kinase (after 4-7 h (MD = - 157.52; 95% CI [- 272.31, - 42.19], p = 0.007), and 24 h (MD = - 136.62; 95% CI [- 267.20, - 6.05], p = 0.04)), as well as creatine kinase muscle brain band (after 44-48 h (MD = - 3.35; 95% CI [- 5.69, - 1.02], p = 0.005)). CONCLUSION: HTK solution had the same efficacy and safety as other cardioplegic solutions in most of the clinical parameters. Furthermore, the solution showed superiority in fastening the recovery and protecting the myocardium at the biochemical level. HTK solution provides longer myocardial protection; therefore, it limits surgical interruption. HTK solution can be used as an alternative to the currently used cardioplegic solutions.

Effectiveness of Bokeria-Boldyrev ACH Solution in Surgerical Treatment of Adult Patients with Obstructive Hypertrophic Cardiomyopathy.

The study examined effectiveness of pharmaco-cold cardioplegia employing solutions of enhanced buffer capacity during surgery of obstructive hypertrophic cardiomyopathy in adult patients (N=51) operated during 2013-2018. In group 1 (N=28), the cardioplegia was performed with HTK (Custodiol) solution, whereas in group 2 (N=23), it was carried out with Bokeria-Boldyrev ACH solution. The mean, minimum, and maximum ages in group 1 were 46, 21, and 64 years, respectively; in group 2 - 42, 14, and 70 years, respectively. In both groups, the patients were subjected to myoectomy of exit pathway in the left ventricle according to Bokeria-Morrow operation and annuloplasty of tricuspid valve accompanied by reconstructive surgery (or replacement) of mitral valve. Atrial fibrillation (if any) was suppressed with cryoablation (-60°Ð¡) of the openings of the right and left pulmonary veins. The surgery was carried out in hypothermic mode at 28°C. The significant intergroup differences were observed in the asystole latent period after the onset of antegrade or retrograde injection of cardioplegic solution. In group 1, the asystole latent periods determined after antegrade or retrograde injection were 53±7 or 170±30 sec, respectively; in group 2 - 32±6 and 97±11 sec (p<0.0001), respectively. The mean times of aortic cross-clumping in groups 1 and 2 were 66±8 and 64±6 min, respectively; the electromechanical action of the heart restored after aortic unclamping in 35±7 and 30±6 sec, respectively. The biochemical and clinical data revealed no significant intergroup differences. Overall, novel Bokeria-Boldyrev ACH cardioplegic solution secured effective protection of the myocardium against intraoperative ischemia in adult patients with obstructive hypertrophic cardiomyopathy and significantly decreased the asystole latent period.

Histidine in Health and Disease: Metabolism, Physiological Importance, and Use as a Supplement.

L-histidine (HIS) is an essential amino acid with unique roles in proton buffering, metal ion chelation, scavenging of reactive oxygen and nitrogen species, erythropoiesis, and the histaminergic system. Several HIS-rich proteins (e.g., haemoproteins, HIS-rich glycoproteins, histatins, HIS-rich calcium-binding protein, and filaggrin), HIS-containing dipeptides (particularly carnosine), and methyl- and sulphur-containing derivatives of HIS (3-methylhistidine, 1-methylhistidine, and ergothioneine) have specific functions. The unique chemical properties and physiological functions are the basis of the theoretical rationale to suggest HIS supplementation in a wide range of conditions. Several decades of experience have confirmed the effectiveness of HIS as a component of solutions used for organ preservation and myocardial protection in cardiac surgery. Further studies are needed to elucidate the effects of HIS supplementation on neurological disorders, atopic dermatitis, metabolic syndrome, diabetes, uraemic anaemia, ulcers, inflammatory bowel diseases, malignancies, and muscle performance during strenuous exercise. Signs of toxicity, mutagenic activity, and allergic reactions or peptic ulcers have not been reported, although HIS is a histamine precursor. Of concern should be findings of hepatic enlargement and increases in ammonia and glutamine and of decrease in branched-chain amino acids (valine, leucine, and isoleucine) in blood plasma indicating that HIS supplementation is inappropriate in patients with liver disease.

Effects of histidine load on ammonia, amino acid, and adenine nucleotide concentrations in rats.

The unique capability of proton buffering is the rationale for using histidine (HIS) as a component of solutions for induction of cardiac arrest and myocardial protection in cardiac surgery. In humans, infusion of cardioplegic solution may increase blood plasma HIS from ~ 70 to ~ 21,000 µM. We examined the effects of a large intravenous dose of HIS on ammonia and amino acid concentrations and energy status of the body. Rats received 198 mM HIS intravenously (20 ml/kg) or vehicle. Samples of blood plasma, urine, liver, and soleus (SOL) and extensor digitorum longus (EDL) muscles were analysed at 2 or 24 h after treatment. At 2 h after HIS load, we found higher HIS concentration in all examined tissues, higher urea and ammonia concentrations in blood and urine, lower ATP content and higher AMP/ATP ratio in the liver and muscles, higher concentrations of almost all examined amino acids in urine, and lower glycine concentration in blood plasma, liver, and muscles when compared with controls. Changes in other amino acids were tissue dependent, markedly increased alanine and glutamate in the blood and the liver. At 24 h, the main findings were lower ATP concentrations in muscles, lower concentrations of branched-chain amino acids (BCAA; valine, leucine, and isoleucine) in blood plasma and muscles, and higher carnosine content in SOL when compared with controls. It is concluded that a load of large HIS dose results in increased ammonia levels and marked alterations in amino acid and energy metabolism. Pathogenesis is discussed in the article.

The effect of antioxidants on angiogenesis in uterine transplantation.

The aim of this study was to investigate the effect of antioxidants on angiogenesis in uterine transplantation. We used 24 female rats equally divided into four groups: Group 1 had the uterus stored in HTK (Histidine-Tryptophan-Ketoglutarate) solution at 4 °C cold storage for 4 h. Group 2 had the uterine tissue stored in HTK solution combined with acetyl L-carnitine (10-8 M) for 4 h at +4 °C. The same procedures with Group 1 and 2 were repeated for 24 h for Groups 3 and 4, respectively. Histological investigation and immunohistochemical analysis were performed. Histological findings showed that storing donor uterus in HTK solution at +4° C for 24 h results in histological alteration in uterus. We also found that immunoreactivity of VEGFR-2 in all layers of rat uterus in Group 2 was lower than that in Group 1, and the expression of the uterus in Group 4 was lower than that in Group 3. We concluded that antioxidant acetyl L-carnitine, which was added to the organ preservation solution HTK, had prevented the formation of free radicals, and thus protected the uterus that was stored in short and long cold storage periods. Impact statement What is already known on this subject? Ischemia-reperfusion is a complex pathophysiological process involve in hypoxia and/or reoxygenation, ionic imbalance-induced oedema and acidosis, oxidative stress, mitochondrial uncoupling, coagulation and endothelium activation. The composition of preservation solutions must be adapted to the severity of ischaemia-reperfusion injuries to reduce cellular damage and inflammation and preserve graft functionality and integrity, thus improving short-term and long-term graft outcome. Clinicians use three types of composition of solution for static cold preservation: intracellular, intermediate and extracellular. HTK will be used frequently, especially with the consideration of lower price and more easy handling aspects. L-carnitine acts as an antioxidant, protects against free radicals and prevents mitochondrial damage. VEGFR-2 plays an important role in angiogenesis, chemotaxis, proliferation and migration of endothelial cells. What this study adds? In this study, we investigate the effect of antioxidants on angiogenesis in uterus transplantation. Our results showed that antioxidant acetyl L-carnitine that added to the organ preservation solution HTK, has prevented the formation of free radicals, thus protect the uterus that was stored in short and long cold storage periods. What the implications are for future studies? Therefore, we will contribute to the literature with the results of this study.

Cytoprotective Mechanisms in Fatty Liver Preservation against Cold Ischemia Injury: A Comparison between IGL-1 and HTK.

Institute Goeorges Lopez 1 (IGL-1) and Histidine-Tryptophan-Ketoglutarate (HTK) preservation solutions are regularly used in clinical for liver transplantation besides University of Wisconsin (UW) solution and Celsior. Several clinical trials and experimental works have been carried out comparing all the solutions, however the comparative IGL-1 and HTK appraisals are poor; especially when they deal with the underlying protection mechanisms of the fatty liver graft during cold storage. Fatty livers from male obese Zücker rats were conserved for 24 h at 4 °C in IGL-1 or HTK preservation solutions. After organ recovery and rinsing of fatty liver grafts with Ringer Lactate solution, we measured the changes in mechanistic target of rapamycin (mTOR) signaling activation, liver autophagy markers (Beclin-1, Beclin-2, LC3B and ATG7) and apoptotic markers (caspase 3, caspase 9 and TUNEL). These determinations were correlated with the prevention of liver injury (aspartate and alanine aminostransferase (AST/ALT), histology) and mitochondrial damage (glutamate dehydrogenase (GLDH) and confocal microscopy findings). Liver grafts preserved in IGL-1 solution showed a marked reduction on p-TOR/mTOR ratio when compared to HTK. This was concomitant with significant increased cyto-protective autophagy and prevention of liver apoptosis, including inflammatory cytokines such as HMGB1. Together, our results revealed that IGL-1 preservation solution better protected fatty liver grafts against cold ischemia damage than HTK solution. IGL-1 protection was associated with a reduced liver damage, higher induced autophagy and decreased apoptosis. All these effects would contribute to limit the subsequent extension of reperfusion injury after graft revascularization in liver transplantation procedures.

Protective Mechanism of containing sevoflurane HTK Solution on Cardiac Electrophysiology in Isolated Rat Cardiac Transplantation / 实用医学杂志

Objective To investigate the electrophysiological protective effect of HTK solution containing sevoflurane on rat cardiac transplantation. Methods Twenty-four male Sprague-Dawley rats were divided into the control group,sevoflurane group and Heptanol group. Rat hearts in 3 groups were stored in HTK solution,containing sevoflurane and sevoflurane+heptanol HTK solution for 6 h. Heart resuscitation time,the duration of arrhythmia and monophasic action potential(MAP)and heart rate(HR)at different time points were recorded.Monophasic action potential duration of repolarization at 50% and 90%(MAPD50 and MAPD90),monophasic action potential amplitude(MAPA)and maximal velocity(Vmax)were analyzed. Results The isolated rat hearts in each group can be successfully restored to the spontaneous heart beat. Compared with group C ,heart resuscitation time in group S and group H was significantly shortened,heart rate(HR)was significantly decreased at T1,MAPD50 and MAPD90 in heart intima and epicardium were shortened at T1 ~ T2,the incidence of ventricular fibrillation and reperfusion arrhythmia Scores were reduced,with the shorter duration of ventricular fibrillation(P<0.05). No significant difference was found in Vmax and MAPA among the three groups at each time point. Conclusion HTK solution containing sevoflurane and HTK solution containing heptanol had similar electrophysiological effects ,which could inhibit the prolonged monophasic action potential(MAP)and reduce arrhythmia. The electrophysiological protective effect of HTK solution containing sevoflurane may be associated with the inhibition of gap junction function.

Assessment of right liver graft perfusion effectiveness between one and two-catheter infusion methods.

BACKGROUNDS/AIMS: Conventional graft perfusion method using one small-caliber catheter takes a relatively long time for right liver graft perfusion, thus some modification is needed. In this study, we intended to assess the effectiveness of right liver graft perfusion methods through comparison of different infusion catheters. METHODS: The study consisted of two parts including one bench experiment to obtain data of hydraulic infusion and one clinical trial of 40 cases on graft perfusion with one- versus two-catheter infusion methods. These two graft infusion methods were compared in terms of the perfusion time and washing-out efficiency. RESULTS: At bench experiment, the infusion flow rate and infusion pressure were 3.3 ml/sec and 1.9 cmH20 in one blood transfusion catheter group, and 11.7 ml/sec and 3.1 cmH20 in single transurethral resection of prostate irrigation catheter group, and 6.6 ml/sec and 2.0 cmH20 in two blood transfusion catheters group, respectively. In clinical trial with 40 right liver grafts, two-catheter group had a shorter graft portal perfusion time for the first 2 L of histidine-tryptophan-ketoglutarate (HTK) solution than the conventional one-catheter group (375±25 seconds vs. 662±34 seconds; p=0.001) and a lower rate of incomplete blood washing-out after the initial 2 L portal perfusion (40% vs. 85%; p=0.03). CONCLUSIONS: The two-catheter infusion method appears to be more effective than the conventional one-catheter infusion method for right liver graft perfusion at the back table. Large size of right liver grafts seems to be its good indication.

Assessment of right liver graft perfusion effectiveness between one and two-catheter infusion methods

BACKGROUNDS/AIMS: Conventional graft perfusion method using one small-caliber catheter takes a relatively long time for right liver graft perfusion, thus some modification is needed. In this study, we intended to assess the effectiveness of right liver graft perfusion methods through comparison of different infusion catheters. METHODS: The study consisted of two parts including one bench experiment to obtain data of hydraulic infusion and one clinical trial of 40 cases on graft perfusion with one- versus two-catheter infusion methods. These two graft infusion methods were compared in terms of the perfusion time and washing-out efficiency. RESULTS: At bench experiment, the infusion flow rate and infusion pressure were 3.3 ml/sec and 1.9 cmH20 in one blood transfusion catheter group, and 11.7 ml/sec and 3.1 cmH20 in single transurethral resection of prostate irrigation catheter group, and 6.6 ml/sec and 2.0 cmH20 in two blood transfusion catheters group, respectively. In clinical trial with 40 right liver grafts, two-catheter group had a shorter graft portal perfusion time for the first 2 L of histidine-tryptophan-ketoglutarate (HTK) solution than the conventional one-catheter group (375+/-25 seconds vs. 662+/-34 seconds; p=0.001) and a lower rate of incomplete blood washing-out after the initial 2 L portal perfusion (40% vs. 85%; p=0.03). CONCLUSIONS: The two-catheter infusion method appears to be more effective than the conventional one-catheter infusion method for right liver graft perfusion at the back table. Large size of right liver grafts seems to be its good indication.

The Effect of Fructose-1,6-diphosphate and HTK Solution on Protecting Primary Cardiac Muscle Cells of Rat with Cold Preservation / 华中科技大学学报（医学）（英德文版）

Summary: In this study we tried to investigate the effect of fructose-1,6-diphosphate and HTK solution on protecting primary cardiac muscle cells of rat with cold preservation. The primary cardiac muscle cells of rat were cultured in vitro with four preservation solutions respectively: 0.9 % sodium chloride solution (group A), FDP (group B), HTK solution (group C) and a mixture of FDP and HTK solution (group D). The cells were preserved for 6, 8 and 10 h at 0-4 ℃. The values of AST and LDH-L and the Na+-K+ ATPase activity in cardiac muscle cells were detected, and the survival rate of cardiac muscle cells was detected with trypan blue staining. The values of AST and LDH-L in group C and group D were remarkable lower those in group A and group B (P<0.001), while the Na+-K+ ATPase activity and the survival rate of cells in group C and group D were much higher than those in group A and group B (P<0.001). The values of AST and LDH-L after 6 hours in group D decreased much more than those in group C (P<0.01), while the Na+-K+ ATPase activity and the survival rate of cells in group D improved more than those in group C (P<0.01). Both of the HTK solution and the mixture of HTK and FDP solution have an evident effect on protecting the primary cardiac muscle cells of rat in vitro with cold preservation, Compared with the HTK solution, the mixture solution has a better short-term protective effect.