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.

Cardioplegia Application with A Hand-Squeezed Cardioplegia Bag. Is It Safe?

OBJECTIVES: Cardioplegia solutions have a role not only in arresting the heart but also in protecting the myocardium from ischemia. While antegrade cardioplegia is given by the heart-lung machine in many centers, it is given by a hand-squeezed bag in very few centers. The pressure of cardioplegia given antegrade from the heart-lung machine is certain (60-90 mmHg). The pressure applied in the cardioplegia method, which is given antegrade with a hand-squeezed bag, is uncertain and variable. We compared the antegrade cardioplegia method applied with a hand-squeezed bag with the antegrade cardioplegia method applied with a roller pump from the heart-lung machine in terms of protecting the myocardium from ischemia. METHODS: Seventy-six patients who did not have an acute myocardial infarction, had normal preoperative cardiac marker (troponin and CK-MB) values, did not undergo redo open heart surgery, had an ejection fraction of 50% and above, and underwent elective two or three-vessel isolated coronary artery bypass surgery were evaluated. While tepid (30-32°C) blood cardioplegia was administered antegrade to 33 patients (Group A) with a hand-squeezed bag, the other 34 patients (Group B) received tepid (30-32°C) antegrade blood cardioplegia from the heart-lung machine. The perioperative and postoperative data of the patients were recorded and compared. To evaluate myocardial damage, postoperative cardiac markers and echocardiography data were evaluated and compared at the fourth hour after the cross-clamp was removed in both groups. RESULTS: When evaluated in terms of preoperative demographic data, preoperative mean EF values and intraoperative data, there was no statistical difference between both groups. When we evaluated in terms of myocardial protection, the mean TnT level was 4.31 ± 1.95 at the 4th hour in Group A and 3.91 ± 1.69 in Group B. Mean 4th hour CK-MB level was 40.84 ± 9.07 in Group A and 38.56 ± 8.07 in Group B. Mean change in EF (%) was -4.09 ± 4.41 in Group A and 3.53 ± 4.53 in Group B. In line with the current data when we evaluated in terms of myocardial protection, we found that there is no statistical difference between the two groups (P = 0.373; P = 0.158; P = 0.523). There was no statistical difference between both groups, in terms of postoperative arrhythmias. None of the patients died, and no patients required an intra-aortic balloon pump. RESULTS: As a result of our study, cardioplegia administration with a certain constant pressure from the roller pump and hand-squeezed bag with uncertain pressure does not make a difference, in terms of myocardial protection. We think that the content and amount of cardioplegia and the preferred time for repeated cardioplegia applications are more important for the protection of the myocardium. METHODS: 76 patients who did not have an acute myocardial infarction, had normal preoperative cardiac marker (troponin and CK-MB) values, did not undergo redo open heart surgery, had an ejection fraction of 50% and above, and underwent elective two or three-vessel isolated coronary artery bypass surgery were evaluated. While tepid(30-32 ° C) blood cardioplegia was administered antegrade to 33 patients(Group A) with a hand-squeezed bag, the other 34 patients(Group B) received tepid(30-32 °C) antegrade blood cardioplegia from the heart-lung machine. The perioperative and postoperative data of the patients were recorded and compared. To evaluate myocardial damage, postoperative cardiac markers and echocardiography data were evaluated and compared at the fourth hour after the cross-clamp was removed in both groups. RESULTS: When evaluated in terms of preoperative demographic data, preoperative mean EF values and intraoperative data there was no statistical difference between both groups. When we evaluated in terms of myocardial protection, the mean TnT level was 4.31 ± 1.95 at the 4th hour in group A and 3.91 ± 1.69 in group B. Mean 4th hour CK-MB level was 40.84 ± 9.07 in group A and 38.56 ± 8.07 in group B. Mean change in EF (%) was -4.09 ± 4.41 in group A and 3.53 ± 4.53 in group B. In line with the current data when we evaluated in terms of myocardial protection; we found that there is no statistical difference between the two groups (p = 0.373; p = 0.158; p = 0.523). There was no statistical difference between both groups in terms of postoperative arrhythmia's. None of the patients died and none of the patients required an intra-aortic balloon pump.

Microplegia in cardiac surgery: Systematic review and meta-analysis.

BACKGROUND: Consensus on the optimum choice of cardioplegia remains elusive. One possibility that has been suggested to have beneficial properties is microplegia, a cardioplegia of reduced crystalloid volume. The aim of this meta-analysis is to comprehensively investigate microplegia against a range of clinical outcomes. METHODS: To identify potential studies, systematic searches were carried out in four databases (eg, Pubmed, EMBASE). The search strategy included the key concepts of "microplegia" OR "mini-cardioplegia" OR "miniplegia" AND "cardiac surgery." This was followed by a meta-analysis investigating: mortality, crystalloid volume; cardiopulmonary bypass time; cross-clamp time; intra-aortic balloon pump use; spontaneous heartbeat recovery; inotropic support; low cardiac output syndrome; myocardial infarction; acute renal failure; atrial fibrillation, reoperation for bleeding; creatine kinase myocardial band (CK-MB); intensive care unit (ICU) time and hospital stay. RESULTS: Eleven studies comprising 5798 participants were analyzed. Microplegia used a lower volume of crystalloids and led to a higher spontaneous return of heartbeat, odds ratio (OR) 4.271 (95% confidence intervals [CIs]: 1.935, 9.423; I2 = 76.57%; P < .001) and a lower requirement for inotropic support, OR: 0.665 (95% CI: 0.47, 0.941; I2 = 3.53%; P = .021). Microplegia was also associated with a lower CK-MB release, mean difference (MD) -6.448 ng/mL (95% CI: -9.386, -3.511; I2 = 0%; P < .001) and a shorter ICU stay, MD: -0.411 days (95% CI: -0.812, -0.009; I2 = 17.65%; P = .045). All other comparisons were nonsignificant. CONCLUSIONS: Microplegia has similar effects to other types of cardioplegia and is beneficial with regard to spontaneous return of heartbeat, inotropic support, ICU stay, and CK-MB release.

Transitioning to Del Nido cardioplegia for all-comers: the next switching gear?

BACKGROUND: Exclusive use of Del Nido cardioplegia administration in all adult patients undergoing cardiac surgery has been studied for operative, postoperative and myocardial protection outcomes. METHODS: From November 2016 to October 2017, Del Nido cardioplegia was used in 131 consecutive patients (DN group). Using a propensity score, DN group was compared to 251 patients having received intermittent cold blood cardioplegia (CB group). RESULTS: Preoperative characteristics were similar in DN and CB groups. Operative outcomes were statistically different (p < 0.0001): cardiopulmonary bypass (CPB) time (DN 105.9 ± 46.5, CB 131.2 ± 38.8); aortic cross-clamp time (DN 80.8 ± 35.5, CB 102.2 ± 31.3); operative time (DN 203.1 ± 65.0, CB 241.5 ± 54.7); total cardioplegia volume (DN 1328 ± 879, CB 3773 ± 1226); and peak glycemia on CPB (DN 8.2 ± 2.3, CB 9.0 ± 1.8). No statistical differences were noted in intensive care unit stay, hospital stay and hospital death. Myocardial protection outcomes were similar: discharge left ventricular ejection fraction (DN 52 ± 11, CB 51 ± 10); Troponin levels at the end of the surgery (DN 871 ± 1623, CB 1958 ± 854), day 1 (DN 853 ± 1139, CB 993 ± 8234) and day 4 (DN 442 ± 540, CB 463 ± 317). CONCLUSION: Del Nido cardioplegia use in all adult cardiac surgeries is associated with improved surgical efficiency. The design of larger trials including adults combined cardiac procedures and emergencies is needed.

Microplegia vs 4:1 Blood Cardioplegia: Effectiveness and Cost Savings in Complex Cardiac Operations.

BACKGROUND: Microplegia has been studied during isolated coronary artery bypass grafting and valve surgery but not in more complex operations. Objectives of this study were to demonstrate safety and effectiveness of microplegia relative to Buckberg cardioplegia during these operations. METHODS: From January 2012 to January 2017, 242 patients underwent multicomponent operations with simplified microplegia delivered via syringe pump and 10,512 with modified Buckberg cardioplegia. Operations included aortic root, arch, or ascending aorta replacement in 424 (94%) patients, aortic valve surgery in 324 (72%) patients, and concomitant coronary artery bypass grafting in 47 (10%) patients. Outcomes were compared in 226 propensity-matched pairs. RESULTS: There was no difference in median postoperative troponin T between groups after adjusting for aortic clamp time. Microplegia patients received significantly less crystalloid with their cardioplegia (mean 27 ± 8.0 mL/operation vs 735 ± 357 mL/operation; P < .001) and had lower peak intraoperative glucose (196 ± 40 mg/dL vs 248 ± 69 mg/dL; P < .001). Microplegia and Buckberg groups had similar in-hospital mortality (2.7% [n = 6] vs 2.2% [n = 5]; P = .8), stroke (2.2% [n = 5] vs 3.6% [n = 8]; P = .4), renal failure (8% [n = 18] vs 5.8% [n = 13]; P = .4), prolonged ventilation (23% [n = 51] vs 24% [n = 54]; P = .7), median postoperative length of stay (both 8.1 days; P > .9), and median red cell units administered to patients requiring transfusion (4 units vs 3 units; P = .14). The mean cost of cardioplegia per case with microplegia was 1/26th that of Buckberg cardioplegia. CONCLUSIONS: Our simplified microplegia technique offers several advantages over Buckberg cardioplegia without compromising myocardial protection or safety in complex, multicomponent operations with extended aortic clamp times.

Modified Glucose-Insulin-Potassium Regimen Provides Cardioprotection With Improved Tissue Perfusion in Patients Undergoing Cardiopulmonary Bypass Surgery.

Background Laboratory studies demonstrate glucose-insulin-potassium (GIK) as a potent cardioprotective intervention, but clinical trials have yielded mixed results, likely because of varying formulas and timing of GIK treatment and different clinical settings. This study sought to evaluate the effects of modified GIK regimen given perioperatively with an insulin-glucose ratio of 1:3 in patients undergoing cardiopulmonary bypass surgery. Methods and Results In this prospective, randomized, double-blinded trial with 930 patients referred for cardiac surgery with cardiopulmonary bypass, GIK (200 g/L glucose, 66.7 U/L insulin, and 80 mmol/L KCl) or placebo treatment was administered intravenously at 1 mL/kg per hour 10 minutes before anesthesia and continuously for 12.5 hours. The primary outcome was the incidence of in-hospital major adverse cardiac events including all-cause death, low cardiac output syndrome, acute myocardial infarction, cardiac arrest with successful resuscitation, congestive heart failure, and arrhythmia. GIK therapy reduced the incidence of major adverse cardiac events and enhanced cardiac function recovery without increasing perioperative blood glucose compared with the control group. Mechanistically, this treatment resulted in increased glucose uptake and less lactate excretion calculated by the differences between arterial and coronary sinus, and increased phosphorylation of insulin receptor substrate-1 and protein kinase B in the hearts of GIK-treated patients. Systemic blood lactate was also reduced in GIK-treated patients during cardiopulmonary bypass surgery. Conclusions A modified GIK regimen administered perioperatively reduces the incidence of in-hospital major adverse cardiac events in patients undergoing cardiopulmonary bypass surgery. These benefits are likely a result of enhanced systemic tissue perfusion and improved myocardial metabolism via activation of insulin signaling by GIK. Clinical Trial Registration URL: clinicaltrials.gov. Identifier: NCT01516138.

Del Nido cardioplegia in isolated adult coronary artery bypass surgery.

BACKGROUND: Del Nido cardioplegia (DC) offers prolonged single-dose myocardial protection in pediatric cardiac surgery. We set out to evaluate the efficacy of DC in adult patients undergoing isolated coronary artery bypass grafting (CABG). METHODS: From January 2012 to October 2017, 851 consecutive isolated CABG surgeries were performed by 2 study surgeons at our center with blood cardioplegia (BC, n = 350), used from January 2012 to April 2014, and DC (n = 501), used from May 2014 to October 2017. Propensity matching was used to yield 325 well-matched pairs. Clinical data were extracted from our local Society of Thoracic Surgeons database and mortality data from the Michigan State Social Security Death Index. RESULTS: Single-dose administration was used in 83% (417/501) of patients receiving DC. In propensity-matched groups, postoperative median troponin T levels (0.28 [0.16-0.59] ng/mL vs 0.46 [0.27-0.81] ng/mL; P < .01) were lower for patients receiving DC, and no difference in ejection fraction on postoperative echocardiography was observed (54 ± 12% and 53 ± 13% for BC and DC, respectively; P = .36). Perioperative outcomes were similar except for greater rate of atrial fibrillation (33% vs 23%; P = .01) in the DC group. Subgroup analyses revealed equivalent myocardial protection and clinical outcomes in patients with age ≥75 years, left ventricular ejection fraction ≤35%, left main disease, or Society of Thoracic Surgeons score ≥2.5%. Four-year survival did not differ between patients undergoing BC or DC. CONCLUSIONS: The current study revealed noninferior myocardial protection and clinical outcomes with DC versus BC in both routine and greater-risk patients undergoing isolated CABG. DC demonstrated the feasibility of single-dose administration for isolated CABG surgery. Larger randomized studies are needed to further explore the safety and efficacy of DC in adult cardiac surgery with longer crossclamp times.

Cardioprotective effect of hyperkalemic cardioplegia in an aquaporin 7-deficient murine heart.

BACKGROUND: Hyperkalemic cardioplegia using St. Thomas' Hospital solution No. 2 (STH2) is commonly used to protect the myocardium during surgery. Mice deficient in the myocyte channel aquaporin 7 (AQP7) show significantly reduced glycerol and ATP contents and develop obesity; however, the influence of AQP7 on cardioplegia effectiveness remains unclear. METHODS: After determining the influence of ischemic duration on cardiac function, isolated hearts of male wild-type (WT) and AQP7-knockout (KO) mice (> 13 weeks old) were aerobically Langendorff-perfused with bicarbonate buffer, and randomly allocated to the control group (25 min of global ischemia) and STH2 group (5 min of STH2 infusion before 20 min of global ischemia, followed by 60 min of reperfusion). RESULTS: Final recovery of left ventricular developed pressure (LVDP) of WT and AQP7-KO hearts in the control group was 24.5 ± 12.4% and 20.6 ± 8.4%, respectively, which were significantly lower than those of the STH2 group (96.4 ± 12.7% and 92.9 ± 27.6%). Troponin T levels of WT and AQP-KO hearts significantly decreased in the STH2 groups (142.9 ± 27.2 and 219.9 ± 197.3) compared to those of the control (1725.0 ± 768.6 and 1710 ± 819.9). CONCLUSIONS: AQP7 was not involved in the protective efficacy of STH2 in this mouse model, suggesting its clinical utility even in complications of metabolic disease.

Single-dose cardioplegia protects myocardium as well as traditional repetitive dosing: A noninferiority randomized study.

OBJECTIVE: The present prospective noninferiority randomized trial was designed to demonstrate the safety and efficacy of a single dose of Custodiol histidine-tryptophan-ketoglutarate compared with repetitive cold-blood cardioplegia. METHODS: From October 2012 to May 2014, 110 patients were randomly assigned to 1 of 2 groups: Group 1 (55 patients) received repetitive cold-blood cardioplegia, and group 2 (55 patients) received single-dose Custodiol histidine-tryptophan-ketoglutarate. Isolated aortic valve replacement, isolated mitral valve replacement, and multivalve procedures represented the most frequent operations, with 39 cases (71%) in group 1 and 49 cases (89%) in group 2. There was no difference in cardiopulmonary bypass time (102 ± 26 minutes vs 99 ± 19 minutes, P = .70) or aortic crossclamp time (77 ± 19 minutes vs 74 ± 17 minutes, P = .33). All patients underwent preoperative electrocardiogram and determination of creatine kinase-MB, troponin I, left ventricular ejection fraction, and regional wall motion. Postoperative cardiac biomarkers were checked at 7, 24, and 48 hours, and an echocardiogram was obtained to check for left ventricular function abnormalities. RESULTS: There was no difference in cardiac biomarkers release between the 2 groups at baseline and 7, 24, and 48 hours postoperatively (creatine kinase, P = .18, troponin P = .23). Left ventricular function was similar between groups preoperatively and at 24 hours after surgery. No death or myocardial infarction was observed in either group. There were no differences in intensive care unit length of stay, incidence of atrial fibrillation, use of inotropes or vasopressors support, time of intubation, or creatinine levels. CONCLUSIONS: A single dose of Custodiol histidine-tryptophan-ketoglutarate cardioplegia is not inferior to repeated cold-blood cardioplegia during elective cardiac surgery.

Single- versus multidose cardioplegia in adult cardiac surgery patients: A meta-analysis.

OBJECTIVE: To compare outcomes of single (intervention group: del Nido [DN], and histamine-tryptophan-ketoglutarate) versus multidose (control group) cardioplegia in the adult cardiac surgery patients. METHODS: Medical search engines were interrogated to identify relevant randomized controlled trials and propensity-score matched cohorts. Meta-analysis was conducted for primary (in-hospital/30-day mortality) and secondary (ischemic and cardiopulmonary bypass [CPB] times, reperfusion fibrillation, peak of cardiac enzymes, myocardial infarction) endpoints. Subgroup analyses were conducted for study design and type of intervention, and meta-regression for primary outcome included type of surgery and left ventricular ejection fraction as moderators. RESULTS: Ten randomized controlled trials and 13 propensity-score matched cohorts were included, reporting on 5516 patients. Estimates are expressed as (parameter value [OR, odds ratio; MD, mean difference; SMD, standardized mean difference]/unit of measure [95% confidence interval], P value). DN reduced ischemic time (MD, -7.18 minutes [-12.52 to -1.84], P < .01), CPB time (MD, -10.44 minutes [-18.99 to -1.88], P .01), reperfusion fibrillation (OR, 0.16 [0.05-0.54], P < .01), and cardiac enzymes (SMD -0.17 [-0.29, 0.05], P < .01) compared with multidose cardioplegia. None of these beneficial effects were reproduced by histamine-tryptophan-ketoglutarate, which instead increased CPB time (MD, 2.04 minutes [0.73-3.37], P < .01) and reperfusion fibrillation (OR, 1.80 [1.20-2.70], P < .01). There was no difference in mortality and myocardial infarction between single and multidose, independently of type of surgery or left ventricular ejection fraction. CONCLUSIONS: DN decreases operative times, reperfusion fibrillation, and surge of cardiac enzymes compared with multidose cardioplegia.

Microplegia versus Cardioplexol® in Coronary Artery Bypass Surgery with Minimal Extracorporeal Circulation: Comparison of Two Cardioplegia Concepts.

BACKGROUND: The aim of this study is to compare the combined use of the Myocardial Protection System and our microplegia (Basel Microplegia Protocol) with Cardioplexol® in coronary artery bypass grafting using the minimal extracorporeal circulation. METHODS: The analysis focused on propensity score matched pairs of patients in whom microplegia or Cardioplexol® was used. Primary efficacy endpoints were high-sensitivity cardiac troponin-T on postoperative day 1 and peak values during hospitalization. Furthermore, we assessed creatine kinase and creatinine kinase-myocardial type, as well as safety endpoints. RESULTS: A total of 56 patients who received microplegia and 155 patients who received Cardioplexol® were included. The use of the microplegia was associated with significantly lower geometric mean (confidence interval) peak values of high-sensitivity cardiac troponin-T (233 ng/L [194-280 ng/L] vs. 362 ng/L [315-416 ng/L]; p = 0.001), creatinine kinase (539 U/L [458-633 U/L] vs. 719 U/L [645-801 U/L]; p = 0.011), and creatinine kinase-myocardial type (13.8 µg/L [9.6-19.9 µg/L] vs. 21.6 µg/L [18.9-24.6 µg/L]; p = 0.026), and a shorter length of stay on the intensive care unit (1.5 days [1.2-1.8 days] vs. 1.9 days [1.7-2.1 days]; p = 0.011). Major adverse cardiac and cerebrovascular events occurred with roughly equal frequency (1.8 vs. 5.2%; p = 0.331). CONCLUSIONS: The use of the Basel Microplegia Protocol was associated with lower peak values of high-sensitivity cardiac troponin-T, creatinine kinase, and creatinine kinase-myocardial type and with a shorter length of stay on the intensive care unit, as compared with the use of Cardioplexol® in isolated coronary artery bypass surgery using minimal extracorporeal circulation.

The Use of del Nido Cardioplegia for Myocardial Protection in Isolated Coronary Artery Bypass Surgery.

BACKGROUND: The del Nido (DN) cardioplegia solution has been widely used in paediatric open-heart surgery for years; however, its application in adult open-heart surgery has not yet gained sufficient popularity. We investigated the safety and efficiency of the DN cardioplegia solution versus the traditional crystalloid cardioplegia solution [St. Thomas' Hospital (STH) cardioplegia solution] in adult patients undergoing coronary artery bypass grafting (CABG). METHODS: A retrospective comparative analysis of 200 consecutive patients undergoing isolated on-pump CABG between April 2016 and September 2017 was performed. Patients were divided into two groups: DN group (n = 100) and STH group (n = 100). Groups were compared with regard to perioperative clinical outcomes, and the safety and efficiency of the DN cardioplegia solution in CABG surgery were evaluated. RESULTS: In the DN group, mean aortic cross-clamp, cardiopulmonary bypass, and total operation times were significantly shorter than in the STH group. After the release of the aortic cross-clamp, the requirement for intraoperative defibrillation was significantly less in the DN group. There were no significant differences between the groups in terms of the levels of perioperative cardiac biomarkers (including creatine kinase-myocardial band and troponin I), major postoperative adverse events, and in-hospital mortality. CONCLUSIONS: This study revealed that the use of the DN cardioplegia solution in adult patients undergoing isolated CABG provides significantly shorter aortic cross-clamp, cardiopulmonary bypass, and total operation times compared with the traditional cardioplegias solution. The DN solution could be used as a safe and efficient alternative to the traditional cardioplegia solutions in CABG surgery.

The del Nido versus cold blood cardioplegia in aortic valve replacement: A randomized trial.

OBJECTIVES: To compare the cardioprotective efficacy of a solution that requires only a single infusion at the start of the ischemic duration versus a solution that requires multiple infusions. METHODS: Aortic valve replacement was performed for 150 patients, who were randomized into the del Nido (DN) cardioplegia group or the cold blood (CB) cardioplegia group. The DN cardioplegia was delivered every 90 minutes and the CB cardioplegia was delivered every 20 to 30 minutes, or whenever cardiac activity was observed. The primary endpoints were electrical cardiac activity during crossclamp, ventricular fibrillation during reperfusion, and postoperative troponin and creatine kinase (CK-MB isoenzyme) at 24 and 48 hours. RESULTS: Electrical activity during crossclamp occurred in 29 (39.7%) patients in the DN group versus 34 (45.3%) patients in the CB group (adjusted P = 1.0). The number of procedures with ventricular fibrillation after removing the crossclamp was 41 (54.7%) in the CB group versus 17 (22.7%) in the DN group (adjusted P = .001; relative risk, 2.41). Troponin values appeared to be lower in the DN group (median, 223.10; interquartile range, 168.35-364.77 pg/mL vs 285.5; 196.20-419.45 pg/mL at 24 hours and 159.60; 125.42-217.20 pg/mL vs 201.60; 160.62-268.45 pg/mL at 48 hours) and CK-MB (median, 14.94; interquartile range, 12.16-20.39 ng/mL vs 17.43; 13.66-22.43 ng/mL at 24 hours and 6.19; 4.41-7.63 ng/mL vs 7.38; 4.74-10.20 ng/mL at 48 hours), but no significance was found. CONCLUSIONS: The del Nido cardioplegia protocol is an acceptable alternative for cold blood cardioplegia in patients undergoing aortic valve replacement.

Myocardial protection with complementary dose of modified Del Nido cardioplegia during heart transplantation.

Myocardial protection during heart transplantation is achieved by a first dose of heart preservation solution during donor heart harvesting, while there is no consensus about the management of complementary doses during implantation in the recipient. We describe a preliminary case series where modified Del Nido Cardioplegia was used as complementary dose at the time of donor heart implantation.

The Relationship between the Use of Cold and Isothermic Blood Cardioplegia Solution for Myocardial Protection during Cardiopulmonary Bypass and the Ischemia-Reperfusion Injury.

PURPOSE: In this study, we aimed to assess myocardial protection and ischemia-reperfusion injury in patients undergoing open heart surgery with isothermic blood cardioplegia (IBC) or hypothermic blood cardioplegia (HBC). MATERIALS AND METHODS: A total of 48 patients who underwent isolated coronary artery bypass grafting or isolated mitral valve surgery between March 2017 and October 2017 were evaluated as randomized prospective study. Study groups (HBC: Group 1, IBC: Group 2) were compared in terms of interleukin 6 (IL-6), IL-8, IL-10, and complement factor 3a (C3a) levels, metabolic parameters, creatine kinase-muscle/brain (CK-MB) and high-sensitivity Troponin I (hsTn-I), and clinical outcomes. RESULTS: Comparison of the markers of ischemia-reperfusion injury showed significantly higher levels of the proinflammatory cytokine IL-6 in the early postoperative period as well as IL-8, in Group 2 (p <0.001), whereas the anti-inflammatory cytokine IL-10 was significantly higher during the X1 time period (p = 0.11) in Group 2, and subsequently it was higher in Group 1. Using myocardial temperature probes, the target myocardial temperatures were measured in the patients undergoing open heart surgery with different routes of cardioplegia, and significant differences were noted (p = 0.000). CONCLUSION: HBC for open heart surgery is associated with less myocardial injury and intraoperative and postoperative morbidity, indicating superior myocardial protection versus IBC.

Prehospital adenosine, lidocaine, and magnesium has inferior survival compared with tactical combat casualty care resuscitation in a porcine model of prolonged hemorrhagic shock.

BACKGROUND: Adenosine, lidocaine, and magnesium (ALM) is a cardioplegic agent shown to improve survival by improving cardiac function, tissue perfusion, and coagulopathy in animal models of shock. We hypothesized prehospital ALM treatment in hemorrhagic shock would improve survival compared to current Tactical Combat Casualty Care (TCCC) resuscitation beyond the golden hour. METHODS: Swine were randomized to: (1) TCCC, (2) 2 mL·kg vehicle control (VC), (3) 2 mL·kg ALM + drip, (4) 4 mL·kg ALM + drip, 5) 4 mL·kg ALM + delayed drip at 0.5 mL·kg·h, 6) 4 mL/kg VC, 7) 4 mL·kg ALM for 15 minutes + delayed drip at 3 mL·kg·h. Animals underwent pressure controlled hemorrhage to mean arterial pressure (MAP) of 30 mm Hg (S = 0). Treatment was administered at T = 0. After 120 minutes of simulated prehospital care (T = 120) blood product resuscitation commenced. Physiologic variables were recorded and laboratories were drawn at specified time points. RESULTS: Tactical Combat Casualty Care demonstrated superior survival to all other agents. The VC and ALM groups had lower MAPs and systolic blood pressures compared with TCCC. Except for the VC groups, lactate levels remained similar with correction of base deficit after prehospital resuscitation in all groups. Kidney function and liver function remained comparable across all groups. Compared with baseline values, TCCC demonstrated significant hypocoagulability. CONCLUSION: Adenosine, lidocaine, and magnesium, as administered in this study, are inferior to current Hextend-based resuscitation for survival from prolonged hemorrhagic shock in this model. In survivors, ALM groups had lower systolic blood pressures and MAPs, but provided a protective effect on coagulopathy as compared to TCCC. Adenosine, lidocaine, and magnesium do not appear to be a suitable low volume replacement to current TCCC resuscitation. The reduced coagulopathy compared to TCCC warrants future studies of ALM, perhaps as a therapeutic adjunct.

Myocardial protection and clinical outcomes in Tetralogy of Fallot patients undergoing intracardiac repair: a randomized study of two cardioplegic techniques.

BACKGROUND: Myocardial protection in Tetralogy of Fallot patients undergoing intracardiac repair is suboptimal due to hypertrophied right ventricle. Hypertrophied myocardium is more susceptible to poor myocardial preservation because of inadequate capillary density as compared to the myocytes. There is a capillary to myocyte ratio mismatch. But del Nido Cardioplegia owing to its less viscosity is able to get more evenly distributed under hypothermic cardiopulmonary bypass as opposed to blood Cardioplegia. We hypothesized that the del Nido Cardioplegia technique, would be beneficial in myocardial protection because of its composition and method of delivery, leading into better early and late clinical outcomes in patients undergoing Tetralogy of Fallot repair as compared to blood cardioplegia reconstituted using St Thomas Cardioplegia solution. The objective of the study was to identify a better technique of myocardial preservation in Tetralogy of Fallot patient. METHODS: In total, 56 Tetralogy of Fallot patients undergoing intracardiac repair under mild hypothermic cardiopulmonary bypass were randomly allocated to receive antegrade Cardioplegia with either standard blood Cardioplegia (Group I) or del Nido Cardioplegia (Group II). Preoperative as well as postoperative data including echocardiographic parameters for right ventricle functions, creatine kinase MB level, inotropic requirement, mechanical ventilation duration, intensive care unit stay and hospital mortality were evaluated. RESULTS: Inotropic score in the first 24 hours postoperatively was significantly lower in Group II compared to Group I (13.4 ± 7.2 vs. 21.2 ± 9.6, p = 0.003). Creatine kinase MB level (ng/mL) was comparable between the groups. Echocardiographic parameters for right ventricle functions were also comparable between the groups during early as well as after 3 to 6 months postoperatively. CONCLUSION: Del Nido Cardioplegia is equally efficacious in providing myocardial protection during intracardiac repair under mild hypothermic cardiopulmonary bypass in Tetralogy of Fallot patients as compared to blood Cardioplegia solution with the added benefit of reducing inotropic requirement in first 24 hours postoperative period.

Myocardial Protection in Minimally Invasive Mitral Valve Surgery: Retrograde Cardioplegia Alone Using Endovascular Coronary Sinus Catheter Compared With Combined Antegrade and Retrograde Cardioplegia.

OBJECTIVE: To compare myocardial protection with retrograde cardioplegia alone with antegrade and retrograde cardioplegia in minimally invasive mitral valve surgery (MIMS). DESIGN: Retrospective study. SETTING: Tertiary care university hospital. PARTICIPANTS: The authors studied 97 MIMS patients using retrograde cardioplegia alone and 118 MIMS patients using antegrade and retrograde cardioplegia. INTERVENTIONS: The data from patients admitted for MIMS using retrograde cardioplegia (MIMS retro) between 2009 to 2012 were compared with the data from patients undergoing MIMS with antegrade and retrograde cardioplegia (MIMS ante-retro) between 2006 and 2010 (control group). Cardioplegia in the MIMS retro group was delivered solely through an endovascular coronary sinus (CS) catheter positioned under echographic and fluoroscopic guidance. Antegrade and retrograde cardioplegia was used in the MIMS ante-retro group. Data regarding myocardial infarction (MI; creatine kinase Mb, troponin T, electrocardiogram), myocardial function, and hemodynamic stability were collected for comparison. MEASUREMENTS AND MAIN RESULTS: Adequate cardioplegia administration (CS pressure >30 mmHg and asystole) was attained in 74.2% of the patients with retrograde cardioplegia alone. In 23.7% of the patients, the addition of an antegrade cardioplegia was necessary. No difference was observed in the incidence of MI (0 MIMS retro v 1 for MIMS ante-retro, p = 0.3623), difficult separation from cardiopulmonary bypass, and postoperative malignant arrhythmia. No difference was found for maximal creatine kinase Mb (39.1 [28.0-49.1] v 37.9 [28.6-50.9]; p = 0.8299) and for maximal troponin T levels (0.39 [0.27-0.70] v 0.47 [0.32-0.79]; p = 0.1231) for MIMS retro and MIMS ante-retro, respectively. However, lactate levels in the MIMS retro group were significantly lower than in the MIMS ante-retro group (2.1 [1.4-3.05] v 2.4 [1.8-3.3], respectively; p = 0.0453). No difference was observed in duration of intensive care unit stay and death. MIMS retro patients had a shorter hospital stay (7.0 [6.0-8.0] v 8.0 [7.0-9.0] days; p = 0.0003). CONCLUSION: Retrograde cardioplegia administration alone provided comparable myocardial protection to antegrade and retrograde cardioplegia during MIMS, but was not sufficient to achieve asystole in one-fifth of patients.

Infused cardioplegia index: A new tool to improve myocardial protection. A cohort study. / Índice de cardioplejía infundida: una nueva herramienta en la protección miocárdica. Un estudio de cohortes.

BACKGROUND: Strategies for cardio-protection are essential in coronary artery bypass graft surgery. The authors explored the relationship between cardioplegia volume, left ventricular mass index and ischemia time by means of the infused cardioplegia index and its relationship with post-operative low cardiac output syndrome. DESIGN: All patients undergoing coronary artery bypass graft surgery between January 2013 and December 2015 were included. Low cardiac output syndrome was defined according to criteria of the SEMICYUC's consensus document. The perioperative factors associated with low cardiac output syndrome were estimated, and using a ROC curve, the optimum cut-off point for the infused cardioplegia index to predict the absence of low cardiac output syndrome was calculated. RESULTS: Of 360 patients included, 116 (32%) developed low cardiac output syndrome. The independent risk predictors were: New York Heart Association Functional Classification (OR 1.8 [95% CI=1.18-2.55]), left ventricle ejection fraction (OR 0.95 (95% CI=0.93-0.98]), ICI (OR 0.99 [95% CI=0.991-0.996]) and retrograde cardioplegia (OR 1.2 [95% CI=1.03-1.50]). The infused cardioplegia index showed an area under the ROC curve of 0.77 (0.70-0.83; P<.001) for the absence of postoperative low cardiac output syndrome using the optimum cut-off point of 23.6ml·min-1(100g/m2 of LV)-1. CONCLUSIONS: The infused cardioplegia index presents an inverse relationship with the development of post-operative low cardiac output syndrome. This index could form part of new strategies aimed at optimising cardio-protection. The total volume of intermittent cardioplegia, especially that of maintenance, should probably be individualised, adjusting for ischemia time and left ventricle mass index.