Blood versus crystalloid cardioplegia during triple valve surgery: A single center experience.

BACKGROUND: The efficacy of different cardioplegia solutions on outcomes of complex cardiac operations such as triple valve surgery (TVS) is scarce. Here we compared the outcomes in TVS patients receiving either crystalloid (Bretschneider) or blood (Calafiore) cardioplegia. METHODS: Screening of our institutional database with prospectively entered data identified 471 consecutive patients (mean age 70.3 ± 9.2 years; 50.9% male), who underwent TVS (replacement or repair of aortic, mitral and tricuspid valve) between December 1994 and January 2013. In 277 patients, cardiac arrest was induced with HTK-Bretschneider solution (HTK, n = 277, 58.8%), whereas 194 received cold blood cardioplegia (BCP) according to Calafiore (n = 194, 41.2%). Comparisons of perioperative and follow up outcomes were made between cardioplegia groups. RESULTS: Preoperative patient characteristics and comorbidities were equally balanced between groups. 30-days mortality was similar between groups (HTK: 16.2%; BCP: 18.2%; p = 0.619). Incidence of the cumulative endpoint (30days mortality, myocardial infarction (MI), arrhythmia, low cardiac output syndrome or need for permanent pacemaker implantation) was also comparable (HTK: 47.6%; BCP: 54.8%, p = 0.149). In patients with reduced left ventricular ejection fraction (LVEF <40%), 30days mortality was higher in the HTK group (HTK 18/71 22.5%; BCP 5/50 10%; p = 0.037). Five-year survival was similar between groups (52 ± 6% for HTK and 55 ± 5% for BCP patients). In-Hospital mortality was best predicted by length of surgery and reperfusion ratio. Decreased age, shorter bypass time, preserved LVEF and concomitant surgical procedures have been found to be protective from long-term mortality. CONCLUSIONS: Myocardial protection with HTK shows equivalent outcomes compared to BCP during TVS. Patients with reduced left ventricular function may benefit from BCP during TVS.

St. Thomas Modified Cardioplegia Effects on Myoblasts' Viability and Morphology.

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

Changes of biventricular function after CABG surgery: does cardioplegia type matter?

AIM: we choose to evaluate, whether type of cardioplegia is an important predictor to determine biventricular function changes after CABG. METHODS: 81 patients who underwent CABG surgery and matched inclusion criteria were enrolled in this study. The exclusion criteria were acute MI within 30 days, impaired systolic left ventricle function (LVEF ⩽35%), atrial fibrillation.TTE was performed for all patients and echocardiographic parameters of biventricular geometry and function were assessed before CABG surgery, first postoperative day and 6 months after surgery. Cardioplegia type was randomly chosen. First group consisted of 49 patients (60.5%) when CC was performed and the others 32 patients (39.5%) formed the second - BC group. RESULTS: Patients' demographic characteristics were similar in both groups, except the lower rates of AH and BSA in BC group (p = 0.015, p = 0.001 respectively). Longer duration of XCT and CBP time was observed in BC group (p = 0.019 and p = 0.028). BC group patients showed more efficient right heart chambers size reduction (p = 0.001 for RV diameter; p = 0.015 for RA diameter) and better improvement of longitudinal RV function (p = 0.02 for TAPSE; p = 0.001 for RV S') 6 months after surgery when compared with CC group patients. RV global systolic function diminished in both groups postoperatively, but the reduction was higher in CC group, although the difference was significant in comparing early postoperative measurements with the late after CABG surgery (p = 0.03). Changes of LV systolic function as well as diameter of LA did not differ between groups (p = 0.165 and p = 0.279, respectively), while diastolic function improved significantly in BC group patients at the late follow-up period: E/e' decreased (p < 0.001) and e' velocity of interventricular septum augmented significantly (p < 0.001). CONCLUSION: BC is associated with better RV reverse remodelling and improvement of longitudinal RV function, as well as LV diastolic function improvement after CABG surgery.

Celsior® crystalloid cardioplegia versus standard hyperkalemic normothermic blood cardioplegia: Analysis of myocardial protection in elective mitral valve repair.

INTRODUCTION: With the increase and refinement of video assisted mitral valve surgery, cristalloïd cardioplegia started regaining popularity. The aim of our study was to evaluate the effectiveness of Celsior®, a crystalloid cardioplegic solution, on myocardial protection in elective surgical mitral valve repair in comparison to blood based hyperkalemic cardioplegia. METHODS: In this observational retrospective study, all consecutive elective isolated surgical mitral valve repair where Celsior® or normothermic hyperkalemic blood cardioplegia were used were included. Primary endpoint was any sign of myocardial protection failure (troponin levels, need for inotropic or mechanical support, rhythm disturbances, mortality). Secondary endpoint was Celsior® safety (allergic reactions, bleeding, organ toxicities). RESULTS: From January 2009 to August 2016, 382 patients underwent elective isolated mitral valve repair in whom normothermic hyperkalemic blood cardioplegia (n = 181) or Celsior® (n = 201) were used. There were no statistically significant differences in baseline characteristics including Euroscore 2. Peak troponin (pg/ml) release and 30-days mortality were not statistically different. Need for cardioversion was significantly more frequent in the Celsior® group (47% vs 13%, p < 0.001). There was no statistical difference in post-operative atrial fibrillation, permanent pacemaker implantation, reoperation for bleeding, transfusion, acute kidney injury, haemoglobin at discharge or length of stay. No allergic reaction to Celsior® occurred. CONCLUSION: Effective myocardial protection was achieved with the Celsior® cardioplegic solution with no unexpected toxicity. Celsior® may be an efficacious and safe cardioprotective strategy in mitral valve repair.

Blood cardioplegia benefits only patients with a long cross-clamp time.

INTRODUCTION: A clear advantage of blood versus crystalloid cardioplegia has not yet been observed in smaller population studies. The purpose of this article was to further investigate the clinical outcomes of blood versus crystalloid cardioplegia in a large propensity-matched cohort of patients who underwent cardiac surgery. METHODS: The study was a single-centre study. Data was withdrawn from the Western Denmark Heart Registry, which comprises a perfusion section for each procedure. A total of 4,852 patients were propensity matched into crystalloid (CC) vs blood cardioplegia (BC) groups. The primary end points were creatinine kinase-MB (CKMB) elevation, acute myocardial infarction (AMI), stroke, dialysis, coronary angiography (CAG) and mortality (30 days and 6 months). RESULTS: We found lower odds ratio in 30-day mortality in the BC group (OR 0.21; CI 0.06-0.68), but no difference in overall 6-month mortality. There was no difference in CKMB elevation, AMI, dialysis or stroke. Several end points were further analysed for different cross-clamp times. In the CC group, ventilation time above 600 minutes was seen more often in almost all cross-clamp time intervals (23.5 % vs 12.2 %; p<0.0001; χ2-test) and 6-month mortality was significantly higher when the cross-clamp time exceeded 210 minutes (64.3 vs 23.8; p=0.018; χ2-test). CONCLUSIONS: We did not find clear evidence of superiority of either type in the uncomplicated patient. When prolonged cross-clamp time or postoperative ventilation is expected, this study indicates that blood cardioplegia might be preferable.

Blood Versus Crystalloid Cardioplegia in Pediatric Cardiac Surgery: A Systematic Review and Meta-analysis.

The benefit of blood cardioplegia (BCP) compared to crystalloid cardioplegia (CCP) is still debatable. Our aim was to systematically review and synthesize all available evidence on the use of BCP and CCP to assess if any modality provides superior outcomes in pediatric cardiac surgery. A systematic literature search of the PubMed and Cochrane databases was performed with respect to the PRISMA statement (end-of-search date: January 30th, 2017). We extracted data on study design, demographics, cardioplegia regimens, and perioperative outcomes as well as relevant biochemical markers, namely cardiac troponin I (cTnI), lactate, and ATP levels at baseline, after reperfusion and postoperatively at 1, 4, 12, and 24 h as applicable. Data were appropriately pooled using random and mixed effects models. Our systematic review includes 56 studies reporting on a total of 7711 pediatric patients. A meta-analysis of the 10 eligible studies directly comparing BCP (n = 416) to CCP (n = 281) was also performed. There was no significant difference between the two groups with regard to cTnI and Lac at any measured time point, ATP levels after reperfusion, length of intensive care unit stay (WMD: -0.08, 95% CI -1.52 to 1.36), length of hospital stay (WMD: 0.13, 95% CI -0.85 to 1.12), and 30-day mortality (OR 1.11, 95% CI 0.43-2.88). Only cTnI levels at 4 h postoperatively were significantly lower with BCP (WMD: -1.62, 95% CI -2.07 to -1.18). Based on the available data, neither cardioplegia modality seems to be superior in terms of clinical outcomes, ischemia severity, and overall functional recovery.

Enhancement of crystalloid cardioplegic protection by structural analogs of apelin-12.

BACKGROUND: C-terminal fragments of adipokine apelin are able to attenuate myocardial ischemia-reperfusion (I/R) injury, but whether their effects are manifested during cardioplegic arrest remain obscure. This study was designed to evaluate the efficacy of natural apelin-12 (H-Arg-Pro-Arg-Leu-Ser-His-Lys-Gly-Pro-Met-Pro-Phe-OH, A12) and its novel structural analogs (H-(N(α)Me)Arg-Pro-Arg-Leu-Ser-His-Lys-Gly-Pro-Nle-Pro-Phe-OH, AI, and N(G)-Arg(N(G)NO2)-Pro-Arg-Leu-Ser-His-Lys-Gly-Pro-Nle-Pro-Phe-NH2, AII) as additives to crystalloid cardioplegia and explore benefits of early reperfusion with these peptides. METHODS: Isolated working rat hearts subjected to normothermic global ischemia and further reperfusion were used. St. Thomas' Hospital cardioplegic solution No.2 (STH2) containing 140 µM A12, AI, or AII was infused for 5 min at 25 °C before ischemia. In separate series, peptide administration was used for 5 min after ischemia. Metabolic state of the hearts was evaluated by myocardial content of high energy phosphates and lactate. Lactate dehydrogenase (LDH) leakage was assessed in myocardial effluent on early reperfusion. RESULTS: Addition of the peptides to STH2 enhanced functional and metabolic recovery of reperfused hearts compared with those of control (STH2 without additives). Cardioplegia with analog AII was the most effective and accompanied by a reduction of postischemic LDH leakage. Infusion of A12, AI, or AII after ischemia improved the majority indices of cardiac function and metabolic state of the heart by the end of reperfusion. However, the overall protective effect of the peptides was less than when they were added to STH2. CONCLUSIONS: Enhancement of apelin bioavailability may minimize myocardial I/R damage during cardiac surgery. Structural analogs of A12 are promising components of clinical cardioplegic solutions.

Cold blood versus crystalloid cardioplegia for myocardial protection in adult cardiac surgery: a meta-analysis of randomized controlled studies.

OBJECTIVE: The purpose of this article was to systematically review randomized controlled trials in which cold blood cardioplegia was compared with cold crystalloid cardioplegia for cardiac surgery. DESIGN: Correlation studies were searched independently in the EMBASE, MEDLINE and Cochrane library databases. The primary endpoints of interest were spontaneous sinus rhythm (SSR) after declamping, perioperative myocardial infarction (MI) and mortality (within 30 days). SETTING: A hospital. PARTICIPANTS: Randomized controlled trials. INTERVENTION: A meta-analysis of 12 studies. MEASUREMENTS AND MAIN RESULTS: The 12 included trials recruited a total of 2866 participants; 1357 patients received cold crystalloid cardioplegia, and 1509 patients received cold blood cardioplegia. The pooled analysis showed no significant difference favoring either cold crystalloid cardioplegia or cold blood cardioplegia in terms of spontaneous sinus rhythm (SSR) after declamping (789/1028 [76.75%] v 773/1025 [75.41%], relative risk (RR) = 0.92 [0.76, 1.13], p = 0.43 with 6 studies included), mortality (within 30 days) (20/1335 [1.50%] v 24/1469 [1.63%], relative risk (RR) = 1.09 [0.62, 1.91], p = 0.77 with 11 studies included), atrial fibrillation (AF) (329/1043 [31.54%] v 365/1040 [35.10%], RR =0.90 [0.80, 1.01], p = 0.08 with 6 studies included) or stroke (45/1114 [4.04%] v 20/1240 [1.61%], RR = 2.18 [0.69, 6.93], p = 0.19 with 4 studies included). The aggregate data showed that the incidence of perioperative myocardial infarction was lower in patients who received cold blood cardioplegia (CB) (32/1310 [2.44%] v 17/1434 [1.19%], RR = 2.30 [1.33, 3.98], p = 0.003 with 11 studies included). CONCLUSIONS: Cold blood cardioplegia reduced perioperative myocardial infarction when compared with cold crystalloid cardioplegia. No differences in the overall incidence rates of spontaneous sinus rhythm, mortality (within 30 days), atrial fibrillation or stroke were observed.

Celsior® vs. St Thomas® cardioplegia: analysis of myocardial protection and clinical safety in neonates.

Objective: To compare the effectiveness and safety of Celsior® crystalloid solution to St Thomas® solution as cardioplegia in pediatric arterial switch surgery. Methods: A retrospective study was conducted on 180 patients who underwent arterial switch operation (ASO) between 2005 and 2019. The patients were divided into two groups: the St Thomas group receiving St Thomas solution and the Celsior® group receiving Celsior® solution. The study aimed to assess myocardial protection while evaluating clinical outcomes of patients between groups. Results: Baseline characteristics not different between groups. The postoperative troponin release trends and blood lactate levels were not different between groups. However, the Celsior® group had a significant lower incidence of delayed sternal closure (9.7% vs. 19.5%; p = 0.09) and mechanical circulatory support (ECMO) (4.9% vs. 24.7%; p < 0.001) compared to the St Thomas group. The length of stay in the intensive care unit (ICU) was significantly shorter in the Celsior® group (4.6 ± 3.36 days vs. 8.72 ± 5.08 days, respectively; p < 0.001). There was no significant difference in 30-day mortality between the two groups (2.9% vs. 2.6%; p = 0.147). Conclusion: The study suggests that Celsior® solution is effective and safe for myocardial protection in pediatric arterial switch surgery. It may offer potential benefits such as reduced need for delayed sternal closure and ECMO support, as well as shorter ICU stay. However, the study has limitations including its retrospective design and the use of different cardioplegic solutions during different time periods. Further prospective randomized trials are needed for confirmation. Clinical Registration Number: ClinicalTrials.gov, ID: NCT04616222.

Single-Dose St. Thomas Versus Custodiol® Cardioplegia for Right Mini-thoracotomy Mitral Valve Surgery.

OBJECTIVE: Custodiol® and St. Thomas cardioplegia are widely employed in mini-thoracotomy mitral valve (MV) operations. One-dose of the former provides 3 h of myocardial protection. Conversely, St. Thomas solution is usually reinfused every 30 min and safety of single delivery is unknown. We aimed to compare single-shot St. Thomas versus Custodiol® cardioplegia. METHODS: Primary endpoint of the prospective observational study was cardiac troponin T level at different post-operative time-points. Propensity-weighted treatment served to adjust for confounding factors. RESULTS: Thirty-nine patients receiving St. Thomas were compared with 25 patients receiving Custodiol® cardioplegia; cross-clamping always exceeded 45 min. No differences were found in postoperative markers of myocardial injury. Ventricular fibrillation at the resumption of electric activity was more frequent following Custodiol® cardioplegia (P = .01). CONCLUSION: Effective myocardial protection exceeding 1 h of ischemic arrest can be achieved with a single-dose St. Thomas cardioplegia in selected patients undergoing right mini-thoracotomy MV surgery.

Myocardial oxygen consumption during histidine-tryptophan-ketoglutarate cardioplegia in young human hearts.

OBJECTIVES: Energy demand and supply need to be balanced to preserve myocardial function during paediatric cardiac surgery. After a latent aerobic period, cardiac cells try to maintain energy production by anaerobic metabolism and by extracting oxygen from the given cardioplegic solution. Myocardial oxygen consumption (MVO2) changes gradually during the administration of cardioplegia. METHODS: MVO2 was measured during cardioplegic perfusion in patients younger than 6 months of age (group N: neonates; group I: infants), with a body weight less than 10 kg. Histidine-tryptophan-ketoglutarate crystalloid solution was used for myocardial protection and was administered during a 5-min interval. To measure pO2 values during cardioplegic arrest, a sample of the cardioplegic fluid was taken from the inflow line before infusion. Three fluid samples were taken from the coronary venous effluent 1, 3 and 5 min after the onset of cardioplegia administration. MVO2 was calculated using the Fick principle. RESULTS: The mean age of group N was 0.2 ± 0.09 versus 4.5 ± 1.1 months in group I. The mean weight was 3.1 ± 0.2 versus 5.7 ± 1.6 kg, respectively. MVO2 decreased similarly in both groups (min 1: 0.16 ± 0.07 vs 0.36 ± 0.1 ml/min; min 3: 0.08 ± 0.04 vs 0.17 ± 0.09 ml/min; min 5: 0.05 ± 0.04 vs 0.07 ± 0.05 ml/min). CONCLUSIONS: We studied MVO2 alterations after aortic cross-clamping and during delivery of cardioplegia in neonates and infants undergoing cardiac surgery. Extended cardioplegic perfusion significantly reduces energy turnover in hearts because the balance procedures are both volume- and above all time-dependent. A reduction in MVO2 indicates the necessity of a prolonged cardioplegic perfusion time to achieve optimized myocardial protection.

Microcirculatory Response to Blood vs. Crystalloid Cardioplegia During Coronary Artery Bypass Grafting With Cardiopulmonary Bypass.

Background: Blood cardioplegia attenuates cardiopulmonary bypass (CPB)-induced systemic inflammatory response in patients undergoing cardiac surgery, which may favorably influence the microvascular system in this cohort. The aim of this study was to investigate whether blood cardioplegia would offer advantages over crystalloid cardioplegia in the preservation of microcirculation in patients undergoing coronary artery bypass grafting (CABG) with CPB. Methods: In this prospective observational cohort study, 20 patients who received crystalloid (n = 10) or blood cardioplegia (n = 10) were analyzed. The microcirculatory measurements were obtained sublingually using incident dark-field imaging at five time points ranging from the induction of anesthesia (T0) to discontinuation of CPB (T5). Results: In the both crystalloid [crystalloid cardioplegia group (CCG)] and blood cardioplegia [blood cardioplegia group (BCG)] groups, perfused vessel density (PVD), total vessel density (TVD), and proportion of perfused vessels (PPV) were reduced after the beginning of CPB. The observed reduction in microcirculatory parameters during CPB was only restored in patients who received blood cardioplegia and increased to baseline levels as demonstrated by the percentage changes from T0 to T5 (%Δ)T0-T5 in all the functional microcirculatory parameters [%ΔTVDT0-T5(CCG): -10.86 ± 2.323 vs. %ΔTVDT0-T5(BCG): 0.0804 ± 1.107, p < 0.001; %ΔPVDT0-T5(CCG): -12.91 ± 2.884 vs. %ΔPVDT0-T5(BCG): 1.528 ± 1.144, p < 0.001; %ΔPPVT0-T5(CCG): -2.345 ± 1.049 vs. %ΔPPVT0-T5(BCG): 1.482 ± 0.576, p < 0.01]. Conclusion: Blood cardioplegia ameliorates CPB-induced microcirculatory alterations better than crystalloid cardioplegia in patients undergoing CABG, which may reflect attenuation of the systemic inflammatory response. Future investigations are needed to identify the underlying mechanisms of the beneficial effects of blood cardioplegia on microcirculation.

Association between cardioplegia and postoperative atrial fibrillation in coronary surgery.

OBJECTIVE: The aim of this multicenter study was to evaluated whether cold or warm cardioplegia are associated with postoperative atrial fibrillation (POAF) and the prognostic role of the latter on early stroke and neurological mortality. METHOD: This was a retrospective analysis of prospective collected data from 9 cardiac centers in Italy and the United States including patients undergoing surgery between 2010 and 2018. From the 9 institutional databases, 17,231 patients underwent isolated CABG on-pump, using either warm cardioplegia (n = 7730) or cold cardioplegia (n = 9501); among the latter group blood and crystalloid cardioplegia were used in 691 and 8810 patients, respectively. After matching, two pairs of 4162 patients (overall cohort 8324) were analyzed. RESULTS: In matched population, the rate of POAF was 18% (1472 cases), 15% (608) in warm group versus 21% (864) in cold group (p < 0.001). Multivariable analysis confirmed that cold cardioplegia was associated with higher rate of POAF, along with age, hypercholesterolemia, LVEF, reoperation, preoperative IABP, previous stroke, cardiopulmonary and cross-clamp. Moreover, cold cardioplegia as well as POAF increased the rate of postoperative stroke as well as early mortality and neurological mortality Propensity-weighted cohort included 11,830 (70%) patients out of 17,231. After adjustment, both cold blood and cold crystalloid cardioplegia negatively influenced POAF, stroke and neurological mortality. CONCLUSIONS: Warm cardioplegia may reduce the rate of POAF in CABG patients with respect to cold cardioplegia, either blood or crystalloid. This has a prognostic impact on postoperative stroke and neurological mortality.

Cardiac surgery in acute myocardial infarction: crystalloid versus blood cardioplegia - an experimental study.

BACKGROUND: Because hearts in acute myocardial infarction are often prone to ischemia-reperfusion damage during cardiac surgery, we investigated the influence of intracellular crystalloid cardioplegia solution (CCP) and extracellular blood cardioplegia solution (BCP) on cardiac function, metabolism, and infarct size in a rat heart model of myocardial infarction. METHODS: Following euthanasia, the hearts of 50 rats were quickly excised, cannulated, and inserted into a blood-perfused isolated heart apparatus. A regional myocardial infarction was created in the infarction group (18 hearts) for 120 min; the control group (32 hearts) was not subjected to infarction. In each group, either Buckberg BCP or Bretschneider CCP was administered for an aortic clamping time of 90 min. Functional parameters were recorded during reperfusion: coronary blood flow, left ventricular developed pressure (LVDP) and contractility (dp/dt max). Infarct size was determined by planimetry. The results were compared between the groups using analysis of variance or parametric tests, as appropriate. RESULTS: Cardiac function after acute myocardial infarction, 90 min of cardioplegic arrest, and 90 min of reperfusion was better preserved with Buckberg BCP than with Bretschneider CCP relative to baseline (BL) values (LVDP 54 ± 11% vs. 9 ± 2.9% [p = 0.0062]; dp/dt max. 73 ± 11% vs. 23 ± 2.7% [p = 0.0001]), whereas coronary flow was similarly impaired (BCP 55 ± 15%, CCP 63 ± 17% [p = 0.99]). The infarct in BCP-treated hearts was smaller (25% of myocardium) and limited to the area of coronary artery ligation, whereas in CCP hearts the infarct was larger (48% of myocardium; p = 0.029) and myocardial necrosis was distributed unevenly to the left ventricular wall. CONCLUSIONS: In a rat model of acute myocardial infarction followed by cardioplegic arrest, application of BCP leads to better myocardial recovery than CCP.

Type of cardioplegic solution as a factor influencing the clinical outcome of open-heart congenital procedures.

INTRODUCTION: Cardioplegia is one of the most important modalities of myocardial protection during heart surgery. AIM: To assess the impact of blood cardioplegia on postoperative variables, in comparison with two types of crystalloid cardioplegic solutions during pediatric heart surgery. MATERIAL AND METHODS: One thousand one hundred and twenty-nine patients underwent surgical correction of congenital heart disease with cardioplegia administration between 2006 and 2012. Nonlinear regression models of postoperative low cardiac output syndrome (LCOS) incidence, catecholamine index and total complication count were developed using a genetic algorithm. The Akaike information criterion was applied for selection of the best model. The following explanatory variables were evaluated: cardioplegia type (ST - Saint Thomas, n = 440; FR - Fresenius, n = 432; BL - Calafiore, n = 257), congenital heart diseases (CHD) type, age, sex, genetic disorder presence, body surface area (BSA), cardiopulmonary bypass (CBP) time, aortic cross-clamp time, operation urgency, redo surgery, surgeon. RESULTS: Low cardiac output syndrome presence and higher than average catecholamine indexes were negatively influenced by use of crystalloid cardioplegia (ST or FR), presence of specific CHDs, redo surgery and prolonged CBP time. Increased complication count was related to: crystalloid cardioplegia, presence of specific CHDs, redo surgery, urgency of operation, operation time and CBP time. Higher BSA had a protective effect against higher catecholamine index and increased complication count. Older age was protective against LCOS. CONCLUSIONS: Cardioplegic solutions type influences postoperative variables in children after heart surgery by the negative impact of crystalloid cardioplegia. Blood cardioplegia presents potential advantages for patients - its application may reduce the incidence of low cardiac output syndrome and related complications.

Cold crystalloid versus warm blood cardioplegia in patients undergoing aortic valve replacement.

BACKGROUND: Myocardial protection techniques during cardiac arrest have been extensively investigated in the clinical setting of coronary revascularization. Fewer studies have been carried out of patients affected by left ventricular hypertrophy, where the choice of type and temperature of cardioplegia remain controversial. We have retrospectively investigated myocardial injury and short-term outcome in patients undergoing aortic valve replacement plus or minus coronary artery bypass grafting with using cold crystalloid cardioplegia (CCC) or warm blood cardioplegia (WBC). METHODS: From January 2015 to October 2016, 191 consecutive patients underwent aortic valve replacement plus or minus coronary artery bypass grafting in normothermic cardiopulmonary bypass. Cardiac arrest was obtained with use of intermittent antegrade CCC group (n=32) or WBC group (n=159), according with the choice of the surgeon. RESULTS: As compared with WBC group, in CCC group creatine-kinase-MB (CK-MB), cardiac troponin I (cTnI), aspartate aminotransferase (AST) release, and their peak levels, were lower during each time points of evaluation, with the greater statistically significant difference at time 0 (P<0.05, for all comparisons). A time 0, CK-MB/CK ratio >10% was 5.9% in CCC group versus 7.8% in WBC group (P<0.0001). At time 0 CK-MB/CK ratio >10% in patients undergoing isolated aortic valve replacement was 6.0% in CCC group versus 8.0% in WBC group (P<0.01). No any difference was found in perioperative myocardial infarction (0% versus 3.8%), postoperative (PO) major complications (15.6% versus 16.4%), in-hospital mortality (3.1% versus 1.3%). CONCLUSIONS: In aortic valve surgery a significant decrease of myocardial enzymes release is observed in favor of CCC, but this difference does not translate into different clinical outcome. However, this study suggests that in presence of cardiac surgical conditions associated with significant left ventricular hypertrophy, i.e., the aortic valve disease, a better myocardial protection can be achieved with the use of a cold rather than a warm cardioplegia. Therefore, CCC can be still safely used.

Novel cardioprotective strategy combining three different preconditioning methods to prevent ischemia/reperfusion injury in aged hearts in an improved rabbit model.

The use of ischemic preconditioning (IPC) to protect the myocardium is usually not effective in elderly patients. The aim of the present study was to design new methods to achieve enhanced myocardial protection, based on the differential role of endogenous adenosine (ADO) and ADO receptors (ARs) in the effects of IPC on young and old animals. An improved New Zealand white rabbit model of ischemia/reperfusion was established based on the Langendorff model. Adult or elderly rabbit hearts, with or without exposure to IPC, were used in order to assess the roles of ADO and ARs in the different effects of IPC. Different protective methods were designed based on a combination of endogenous and exogenous interventions. Cardiac function, as well as biochemical, histopathological and apoptotic indices, were measured in the different intervention groups. The improved Langendorff model was stable, reliable and suitable for the undertaking of the experiments. The ADO levels in the aged rabbit hearts pre- and post-IPC were lower than those in the adult hearts, indicating that ADO levels may be an endogenous factor influencing IPC. A new protection strategy combining ADO-enhanced IPC, A1AR agonist 2-chloro-N(6)-cyclopentyladenosine preconditioning and cold crystalloid cardioplegia had a significant protective effect in aged hearts. The results of the present study suggested that endogenous ADO enhancement, A1AR agonist preconditioning and exogenous treatment yield an additive effect in aged rabbit hearts. The simultaneous application of these three types of intervention provided the most effective myocardial protection in the improved aged rabbit heart model.

Is there a rationale for short cardioplegia re-dosing intervals?

While cardioplegia has been used on millions of patients during the last decades, the debate over the best technique is still going on. Cardioplegia is not only meant to provide a non-contracting heart and a field without blood, thus avoiding the risk of gas emboli, but also used for myocardial protection. Its electromechanical effect is easily confirmed through direct vision of the heart and continuous electrocardiogram monitoring, but there is no consensus on the best way to assess the quality of myocardial protection. The optimal approach is thus far from clear and the considerable amount of literature on the subject fails to provide a definite answer. Cardioplegia composition (crystalloid vs blood, with or without various substrate enhancement), temperature and site(s) of injection have been extensively researched. While less frequently studied, re-dosing interval is also an important factor. A common and intuitive idea is that shorter re-dosing intervals lead to improved myocardial protection. A vast majority of surgeons use re-dosing intervals of 20-30 min, or even less, during coronary artery bypass graft and multidose cardioplegia has been the "gold standard" for decades. However, one-shot cardioplegia is becoming more commonly used and is likely to be a valuable alternative. Some surgeons prefer the comfort of single-shot cardioplegia while others feel more confident with shorter re-dosing intervals. There is no guarantee that a single strategy can be safely applied to all patients, irrespective of their age, comorbidities or cardiopathy. The goal of this review is to discuss the rationale for short re-dosing intervals.