Del Nido cardioplegia versus cold blood cardioplegia in adult cardiac surgery: a meta-analysis of randomized clinical trials

OBJECTIVE

Systematic evaluation of the safety of del Nido cardioplegia compared to cold blood cardioplegia in adult cardiac surgery.

METHODS

We systematically searched PubMed, EMbase, The Cochrane Library and ClinicalTrials.gov for randomized clinical trials (published by 14 January 2024) comparing del Nido cardioplegia to cold blood cardioplegia in adult. Our main endpoints were myocardial injury markers and clinical outcomes. We assessed pooled data by use of a random-effects model or a fixed-effects model.

RESULTS

A total of 10 studies were identified, incorporating 889 patients who received del Nido cardioplegia and 907 patients who received cold blood cardioplegia. The meta-analysis results showed that compared with the cold blood cardioplegia, the del Nido cardioplegia had less volume of cardioplegia, higher rate of spontaneous rhythm recovery after cross clamp release, lower levels of postoperative cardiac troponin T and creatinine kinase-myocardial band, all of which were statistically significant. However, there was no statistically significant difference in postoperative troponin I and postoperative left ventricular ejection fraction. The clinical outcomes including mechanical ventilation time, intensive care unit stay time, hospital stay time, postoperative stroke, postoperative new-onset atrial fibrillation, postoperative heart failure requiring intra-aortic balloon pump mechanical circulation support, and in-hospital mortality of both are comparable.

CONCLUSION

Existing evidence suggests that del Nido cardioplegia reduced volume of cardioplegia administration and attempts of defibrillation. The superior postoperative results in CTnT and CK-MB may provide a direction for further research on improvement of the composition of cardioplegia.

Whole Blood del Nido versus Cold Blood Microplegia in Adult Cardiac Surgery: A Propensity-Matched Analysis

Objectives  Few studies have evaluated the outcomes of whole blood microplegia in adult cardiac surgery. Our novel protocol includes removing the crystalloid portion and using the Quest Myocardial Protection System (MPS) for the delivery of del Nido additives in whole blood. This study sought to compare early and late clinical outcomes of whole blood del Nido microplegia (BDN) versus cold blood cardioplegia (CBC) following adult cardiac surgery. Materials and Methods  A total of 361 patients who underwent cardiac surgery using BDN were compared with a contemporaneous control group of 934 patients receiving CBC. Propensity matching yielded 289 BDN and 289 CBC patients. Chi-square analysis and Fisher's exact test were performed to compare preoperative, operative, and postoperative characteristics on the matched data. Primary outcome was operative mortality, and secondary outcomes included clinical outcomes such as stroke, cardiac arrest, and intra-aortic balloon pump use. The Kaplan-Meier method was used to compare actuarial survival between the two groups using a log-rank test. Results  After matching, preoperative characteristics and surgery type were similar between groups. Cardioplegia type did not affect the primary end point of operative mortality. The rate of postoperative intra-aortic balloon pump was lower in BDN patients compared with CBC patients (0 vs. 2%; p  = 0.01). There was no difference in late survival. Conclusion  Our novel protocol BDN was comparable with CBC, with similar clinical outcomes and no difference in operative mortality or actuarial survival. Further studies should evaluate the long-term outcomes of this technique.

Novel Strategies to Improve the Cardioprotective Effects of Cardioplegia

The use of cardioprotective strategies as adjuvants of cardioplegic solutions has become an ideal alternative for the improvement of post-surgery heart recovery. The choice of the optimal cardioplegia, as well as its distribution mechanism, remains controversial in the field of cardiovascular surgery. There is still a need to search for new and better cardioprotective methods during cardioplegic procedures. New techniques for the management of cardiovascular complications during cardioplegia have evolved with new alternatives and additives, and each new strategy provides a tool to neutralize the damage after ischemia/reperfusion events. Researchers and clinicians have committed themselves to studying the effect of new strategies and adjuvant components with the potential to improve the cardioprotective effect of cardioplegic solutions in preventing myocardial ischemia/reperfusion-induced injury during cardiac surgery. The aim of this review is to explore the different types of cardioplegia, their protection mechanisms, and which strategies have been proposed to enhance the function of these solutions in hearts exposed to cardiovascular pathologies that require surgical alternatives for their corrective progression.

Theoretical and Practical Aspects in the Use of Bretschneider Cardioplegia

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

Relevance and Recommendations for the Application of Cardioplegic Solutions in Cardiopulmonary Bypass Surgery in Pigs

Cardioplegic solutions play a major role in cardiac surgery due to the fact that they create a silent operating field and protect the myocardium against ischemia and reperfusion injury. For studies on cardioplegic solutions, it is important to compare their effects and to have a valid platform for preclinical testing of new cardioplegic solutions and their additives. Due to the strong anatomical and physiological cardiovascular similarities between pigs and humans, porcine models are suitable for investigating the effects of cardioplegic solutions. This review provides an overview of the results of the application of cardioplegic solutions in adult or pediatric pig models over the past 25 years. The advantages, disadvantages, limitations, and refinement strategies of these models are discussed.

Comparison between Custodiol, del Nido and modified del Nido in the myocardial protection - Cardioplegia Trial: a study protocol for a randomised, double-blind clinical trial

INTRODUCTION

Myocardial protection is essential for successful cardiac surgery, and the search for an ideal cardioplegic solution has continued since its beginning. In this context, Custodiol, del Nido and modified del Nido are single-dose cardioplegic solutions with good safety profiles and great relevance in modern surgical practice. While these solutions have all been evaluated for their impact on patient outcomes independently, limited research exists comparing them directly. Thus, the present study aims to examine the effects of these cardioplegic solutions on myocardial protection and clinical outcomes in adult patients undergoing elective cardiac surgery. The assessment of the increase in myocardial injury biomarkers in patients submitted to all treatment methods may be considered a major strength of our study.

METHODS AND ANALYSIS

This is a clinical trial study protocol that will compare myocardial protection and clinical outcomes among three patient groups based on which cardioplegic solution was used. Patients will be randomised to receive del Nido (n=30), modified del Nido (n=30) or Custodiol (n=30). Myocardial injury biomarkers will be measured at the baseline and 2 hours, 12 hours and 24 hours after the cardiopulmonary bypass. Clinical outcomes will be assessed during the trans operative period and the intensive care unit stay, in addition to other haematological parameters.

ETHICS AND DISSEMINATION

This protocol and its related documents were approved by the Research Ethics Committee of the Hospital Nossa Senhora da Conceição, Brazil, registered under no. 4.029.545. The findings of this study will be published in a peer-reviewed journal in the related field.

TRIAL REGISTRATION NUMBER

RBR-7g5s66.

Investigation of myocardial protection during pediatric CPB: Practical experience in 100 Chinese hospitals

Many measures have been proposed for myocardial protection in pediatric congenital heart surgeries, but little data is available for China. This study investigates myocardial protection strategies in pediatric cardiopulmonary bypass (CPB) throughout China. Online questionnaires were delivered to 100 hospitals in 27 provinces. The number of yearly on-pump pediatric cardiovascular surgeries in these hospitals varied greatly. About 91.0% of respondents believe that each surgery should have at least two perfusionists, while only 64.0% of hospitals actually met this requirement. For pediatric patients, crystalloid cardioplegia was more prevalent than blood-based cardioplegia. Histidine-tryptophan-ketoglutarate solution and St. Thomas crystalloid solution were dominant among crystalloid cardioplegia. Del Nido cardioplegia and St. Thomas blood-based cardioplegia ranked the top two in the popularity of blood-based cardioplegia. Dosages varied among different kinds of cardioplegia. In the choice of different cardioplegia, perfusionists mainly focused on myocardial protective effect and cost. Hypothermia of cardioplegia solution was maintained by ice buckets in 3/4 of the hospitals in this survey. In conclusion, the essence of myocardial protection management during pediatric CPB was cardiac arrest induced by cardioplegia under systemic hypothermia. However, there is no uniform standard for the type of cardioplegia, or dosages. Therefore, well-designed multicenter randomized controlled trials are warranted to provide tangible evidence for myocardial protection of cardioplegia in pediatric CPB.

Using near-infrared spectroscopy myocardial oximetry to monitor myocardial oxygen balance in a swine model of cardiac surgery: a descriptive study

Monitoring of the adequacy of myocardial protection with cardioplegia is nearly non-existent in clinical cardiac surgical practice and instead relies on well-defined protocols for delivery of cardioplegia often resulting in inadequate protection. We hypothesized that Near Infrared Spectroscopy technology could be useful in the monitoring of the myocardial oxygen state by attaching the monitors to the epicardium in a porcine model of cardiac surgery. The experiments were conducted with 3 different protocols of 2 pigs each for a total of 6 pigs. The objective was to induce episodic, oxygen supply-demand mismatch. Methods for decreased supply included decreasing coronary blood flow, coronary blood hypoxemia, coronary occlusion, hypovolemia, and hypotension. Methods for increase demand included rapid ventricular pacing and the administration of isoproterenol. Changes in myocardial tissue oximetry were measured and this measurement was then correlated with blood hemoglobin saturations of oxygen from coronary sinus blood samples. We found that decreases in myocardial oxygen supply or increases in demand due to any of the various experimental conditions led to decreases in both myocardial tissue oximetry and hemoglobin oxygen saturation of coronary sinus blood with recovery when the conditions were returned to baseline. Correlation between myocardial tissue oximetry and hemoglobin oxygen saturation of coronary sinus blood was moderate to strong under all tested conditions. This may have translational applications as a monitor of adequacy of myocardial protection and the detection of coronary occlusion.

Myocardial protection in cardiac surgery: how limited are the options? A comprehensive literature review

For patients undergoing cardiopulmonary bypass, myocardial protection is a key for successful recovery and improved outcomes following cardiac surgery that requires cardiac arrest. Different solutions, components and modes of delivery have evolved over the last few decades to optimise myocardial protection. These include cold and warm and blood and crystalloid solution through antegrade, retrograde or combined cardioplegia delivery approach. However, each method has its own advantages and disadvantages, posing a challenge to establish a gold-standard cardioplegic solution with an optimised mode of delivery for enhanced myocardial protection during cardiac surgery. The aim of this review is to provide a brief history of the development of cardioplegia, explain the electrophysiological concepts behind myocardial protection in cardioplegia, analyse the current literature and summarise existing evidence that warrants the use of varying cardioplegic techniques. We provide a comprehensive and comparative overview of the effectiveness of each technique in achieving optimal cardioprotection and propose novel techniques for optimising myocardial protection in the future.

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.

Mitochondrial Dysfunction in Cardiac Surgery

Mitochondria are key to the cellular response to energetic demand, but are also vital to reactive oxygen species signaling, calcium hemostasis, and regulation of cell death. Cardiac surgical patients with diabetes, heart failure, advanced age, or cardiomyopathies may have underlying mitochondrial dysfunction or be more sensitive to perioperative mitochondrial injury. Mitochondrial dysfunction, due to ischemia/reperfusion injury and an increased systemic inflammatory response due to exposure to cardiopulmonary bypass and surgical tissue trauma, impacts myocardial contractility and predisposes to arrhythmias. Strategies for perioperative mitochondrial protection and recovery include both well-established cardioprotective protocols and targeted therapies that remain under investigation.

Safe cross-clamp time using Custodiol®-histidine-tryptophan-ketoglutarate cardioplegia in the adult

INTRODUCTION

Safe cross-clamp time using single-dose Custodiol^®-histidine-tryptophan-ketoglutarate cardioplegia has not been established conclusively.

METHODS

Immediate post-operative outcomes of 1,420 non-consecutive, cardiac surgery patients were reviewed retrospectively. Predictors of a combined endpoint made of in-hospital mortality and any major complication post-surgery were found with the multivariable method. Analysis of variance was used to evaluate the impact of cross-clamp time on most relevant complications. Discriminatory power and cut-off value of cross-clamp time were established for in-hospital mortality and each of the major complications (receiver operating characteristic curve analysis). A comparative analysis (with propensity matching) with multidose cold blood cardioplegia on in-hospital mortality post-surgery was performed in non-coronary surgery patients.

RESULTS

Coronary, aortic valve and mitral valve surgery and surgery on thoracic aorta were performed in 45.4%, 41.9%, 49.5%, 20.6% of cases, respectively. In-hospital mortality and the rate of any major complication post-surgery were 6.5% and 41.9%, respectively. Cross-clamp time had significant impact on in-hospital mortality and almost all major post-operative complications, except neurological dysfunctions (p = 0.084), myocardial infarction (p = 0.12) and mesenteric ischaemia (p = 0.85). Areas under the receiver operating characteristic curve and the optimal cut-off values for in-hospital mortality and any major complication were of 0.657, 0.594, >140 and >127 minutes, respectively. Comorbidities-adjusted odds ratio for any major complication of cross-clamp time <127 minutes was 1.86 (p < 0.0001). Despite similar in-hospital mortality (p = 0.57), there was an earlier significant increase of mortality in Custodiol-HTK than in multidose cold blood propensity-matched, non-coronary surgery patients.

CONCLUSIONS

The use of Custodiol-HTK cardioplegia is associated with a low risk of serious post-operative complications provided that cross-clamp time is of 2 hours or less.

Lidocaine and Pinacidil Added to Blood versus Crystalloid Cardioplegic Solutions: Study in Isolated Hearts

OBJECTIVE

The present study aimed the functional recovery evaluation after long term of cardiac arrest induced by Custodiol (crystalloid-based) versus del Nido (blood-based) solutions, both added lidocaine and pinacidil as cardioplegic agents. Experiments were performed in isolated rat heart perfusion models.

METHODS

Male rat heart perfusions, according to Langendorff technique, were induced to cause 3 hours of cardiac arrest with a single dose. The hearts were assigned to one of the following three groups: (I) control; (II) Custodiol-LP; and (III) del Nido-LP. They were evaluated after ischemia throughout 90 minutes of reperfusion. Left ventricular contractility function was reported as percentage of recovery, expressed by developed pressure, maximum dP/dt, minimum dP/dt, and rate pressure product variables. In addition, coronary resistance and myocardial injury marker by alpha-fodrin degradation were also evaluated.

RESULTS

At 90 minutes of reperfusion, both solutions had superior left ventricular contractile recovery function than the control group. Del Nido-LP was superior to Custodiol-LP in maximum dP/dt (46%±8 vs. 67%±7, P<0.05) and minimum dP/dt (31%±4 vs. 51%±9, P<0.05) variables. Coronary resistance was lower in del Nido-LP group than in Custodiol-LP (395%±50 vs. 307%±13, P<0.05), as well as alpha-fodrin degradation, with lower levels in del Nido-LP group (P<0.05).

CONCLUSION

Del Nido-LP cardioplegia showed higher functional recovery after 3 hours of ischemia. The analysis of alpha-fodrin degradation showed del Nido-LP solution provided greater protection against myocardial ischemia and reperfusion (IR) in this experimental model.

Myocardial protection in on-pump coronary artery bypass grafting surgery: analysis of the effectiveness of the use of retrograde Celsior®

BACKGROUND

We analyzed the adequacy of the myocardial protection achieved with a single dose of retrograde crystalloid Celsior®, compared with an accepted standard (microplegia), in on-pump coronary artery bypass grafting surgery (CABG).

METHODS

This was a retrospective comparative clinical study conducted in a single institution that included all the patients operated on who had elective isolated on-pump CABG, from March 2006 to June 2014. We evaluated maximum postoperative troponin T (TnT) as a marker of myocardial damage, adjusted for possible confounders using propensity score matching. We also analyzed markers of recovery of myocardial function, and the safety of the intravenous use of Celsior®.

RESULTS

During the study period, 261 patients were included, divided in two groups: (a) continuous retrograde blood-based microplegia (114 patients); (b) retrograde single-dose crystalloid Celsior® (147 patients). The propensity score adjusted maximum TnT was significantly lower in the Celsior group [average treatment effect = -0.55 ng/dl; 95% confidence interval (CI) -1.10 to -0.1 ng/dl; p = 0.048]. There were no differences in the postoperative use of intra-aortic balloon of counterpulsation or in the requirements of high-dose inotropic medications. In-hospital mortality was equivalent in both study groups ( p = 0.73); surgical re-exploration because of bleeding was equivalent ( p = 0.37). There were no differences in prolonged mechanical ventilation ( p = 0.65) and intensive care unit length of stay ( p = 0.87).

CONCLUSION

An isolated single dose of retrograde Celsior® may be an effective and safe myocardial protection strategy in on-pump CABG.

Left ventricular dysfunction after two hours of polarizing or depolarizing cardioplegic arrest in a porcine model

INTRODUCTION

This experimental study compares myocardial function after prolonged arrest by St. Thomas' Hospital polarizing cardioplegic solution (esmolol, adenosine, Mg²⁺) with depolarizing (hyperkalaemic) St. Thomas' Hospital No 2, both administered as cold oxygenated blood cardioplegia.

METHODS

Twenty anaesthetized pigs on tepid (34°C) cardiopulmonary bypass (CPB) were randomised to cardioplegic arrest for 120 min with antegrade, repeated, cold, oxygenated, polarizing (STH-POL) or depolarizing (STH-2) blood cardioplegia every 20 min. Cardiac function was evaluated at Baseline and 60, 150 and 240 min after weaning from CPB, using a pressure-conductance catheter and epicardial echocardiography. Regional tissue blood flow, cleaved caspase-3 activity and levels of malondialdehyde were evaluated in myocardial tissue samples.

RESULTS

Preload recruitable stroke work (PRSW) was increased after polarizing compared to depolarizing cardioplegia 150 min after declamping (73.0±3.2 vs. 64.3±2.4 mmHg, p=0.047). Myocardial tissue blood flow rate was high in both groups compared to the Baseline levels and decreased significantly in the STH-POL group only, from 60 min to 150 min after declamping (p<0.005). Blood flow was significantly reduced in the STH-POL compared to the STH-2 group 240 min after declamping (p<0.05). Left ventricular mechanical efficiency, the ratio between total pressure-volume area and blood flow rate, gradually decreased after STH-2 cardioplegia and was significantly reduced compared to STH-POL cardioplegia after 150 and 240 min (p<0.05 for both).

CONCLUSION

Myocardial protection for two hours of polarizing cardioplegic arrest with STH-POL in oxygenated blood is non-inferior compared to STH-2 blood cardioplegia. STH-POL cardioplegia alleviates the mismatch between myocardial function and perfusion after weaning from CPB.

Comparison of del Nido Cardioplegia With Blood Cardioplegia in Adult Combined Surgery

OBJECTIVE

del Nido solution (DNS) is a single-dose cardioplegia designed for pediatric use proposed to offer superior myocardial protection in adults. However, few data support this claim. We hypothesized that DNS and modified blood cardioplegia solution (BS) provide equivalent safety in combined adult valve surgery.

METHODS

Between November 2014 and December 2015, 25 patients underwent primary aortic valve replacement and concomitant coronary artery bypass grafting (CABG) with DNS. Outcomes were compared with 25 patients who underwent the same surgery with BS between September 2013 and August 2015.

RESULTS

All preoperative characteristics, comorbidities, and number of CABG performed were similar between groups. One hospital death occurred in the BS group. Postoperative creatine kinase, MB isotype (16.7 ± 5.3 μg/L vs. 22.1 ± 8.9 μg/L, P = 0.011) and troponin T levels (260 ± 105.3 ng/L vs. 370.5 ± 218.4 ng/L, P = 0.028) were significantly lower in the DNS group. There was no difference in inotropic or vasoactive agent use (P = 0.512). Cardiopulmonary bypass times (65.5 ± 12.5 min vs. 76.6 ± 19.1 min, P = 0.019) and cross-clamp times (55.6 ± 11.2 min vs. 64.3 ± 18.9 min, P = 0.05) were lower in the DNS group but total operating room times (P = 0.198) were similar. Peak postoperative creatinine levels were similar in both groups (P = 0.063). There was no difference in postoperative outcomes including acute renal failure (P > 0.999), atrial fibrillation (P = 0.773), acute respiratory failure (P > 0.999), nor stroke or transient ischemic attack (P > 0.999). Intensive care unit stay (P = 0.213) and hospital stay (P = 0.1) did not differ between groups.

CONCLUSIONS

The DNS can be used as an alternative to BS in adult concomitant aortic valve replacement + CABG surgery. This supports our hypothesis that in this specific setting, DNS provides comparable myocardial protection as BS, with possibly shorter cardiopulmonary bypass and cross-clamp times.

Does the type of cardioplegia used during valve surgery influence operative nadir hematocrit and transfusion requirements?

INTRODUCTION

Myocardial protection is performed using diverse cardioplegic (CP) solutions with various combinations of chemical and blood constituents. Newer CP formulations that extend ischemic intervals may require greater asanguineous volume, contributing to hemodilution.

METHODS

We evaluated intraoperative hemodilution and red blood cell (RBC) transfusion rates among three common CP solutions during cardiac valve surgery. Data from 5,830 adult cardiac primary valve procedures where either four-to-one blood CP (4:1), del Nido solution (DN) or microplegia (MP) was used at 173 United States surgical centers. The primary outcome was the nadir hematocrit (Hct) during cardiopulmonary bypass (CPB), with a secondary outcome of total units of RBC transfused intraoperatively. Outcomes were assessed using mixed-effects regression, with controls for patient size, age, first Hct in the operating room, ultrafiltration volume, net bypass circuit priming volume, anesthesia and perfusion asanguineous volumes, cross-clamp and total procedure times, procedure type, reoperation, hospital, surgeon and twelve other patient and procedural variables.

RESULTS

A total of 2,641 patients received 4:1 (45.3%), 1,864 received DN (32.0%) and 1,325 received MP (22.7%). There were only slight differences in the central tendency (mean (SD)) for crude nadir Hct on CPB: 4:1, 25.5 (4.5), DN, 26.0 (4.6) and MP, 26.5 (4.7). After controlling for numerous operative and patient characteristics, the regression-adjusted estimate of the nadir Hct on CPB for MP was 26.2%, compared to 25.7% for 4:1 and 25.7% for DN; differences between MP and the other methods were statistically significant (p<0.01). Unadjusted mean RBC units transfused per patient was very similar across the groups (4:1, 2.2; MP, 2.3; DN, 2.4). Regression-adjusted estimates for the number of units of RBC transfused intraoperatively showed no statistically significant differences between CP methods.

CONCLUSIONS

In patients undergoing cardiac valve surgery, the type of CP did not have a strong clinical impact on hemodilution or transfusion. Choice of a myocardial preservation solution can be made independently of its effect on intraoperative Hct.

Clinical and economic benefits of advanced microplegia delivery system in cardiac surgery: evidence from 250 hospitals

AIM

Determine the impact of a second generation microplegia delivery system (MPS2) compared with traditional cardioplegia. Materials &  methods: Multivariable difference-in-differences analysis using fixed effects was performed for each outcome: adverse event (AE) composite, total visit cost, medication cost, length of stay (LOS) and  intensive care unit (ICU) days.

RESULTS

A 2.25% absolute risk reduction in AE composite was found with MPS2 compared with traditional cardioplegia, which equates to relative risk reduction of 5.25%. Significant reductions in LOS and ICU days (0.1 α level). Per case reduction of US$1231 total visit and US$192 medication costs were found in MPS2 hospitals.

CONCLUSION

For hospitals with MPS2, significant reductions were seen in AEs, LOS and ICU days, which lead to reductions in total visit and medication costs.

Hearts during ischemia with or without HTK-protection analysed by dielectric spectroscopy

OBJECTIVE

We investigated canine hearts during ischemia after aortic cross clamping (UI, n  =  20) and after HTK-cardioplegia (HTK, n  =  24) at 35 °C, 25 °C, 15 °C, and 5 °C with the aim to compare tissue changes caused by the activity of anaerobic metabolism(AAM), cell membrane destruction(CD), and gap junction uncoupling(GJU).

APPROACH

We measured continuously the complex dielectric spectrum(DS), ATP- and lactate content, extracellular pH, and rigor contracture. To identify changes in DS caused by AAM, CD, and GJU we performed additional experiments on the gap junction-free skeletal muscle. We used heart model simulations to calculate the effect of temperature.

MAIN RESULTS

AAM affected the DS at 10 MHz and we found a strong correlation between DS and the proton concentration with a maximum of DS at 10 mmol g^-1 dry weight in ATP-concentration. The time of GJU was detected by a characteristic increase in DS and CD by a characteristic decrease at 13 kHz. In comparison to UI, GJU, AAM and CD were delayed by HTK and by hypothermia, indicating a minimization of energy consumption and an improved preservation of tissue structure.

SIGNIFICANCE

The novel findings were that in UI at 5 °C GJU occurred earlier and AAM remained constant, indicating a less effective preservation in UI by deep hypothermia in contrast to HTK.