Bretschneider and del Nido solutions: Are they safe for coronary artery bypass grafting? If so, how should we use them?

[Clinical, biochemical and histological indicators of Del Nido cardioplegia efficacy in patients with severe myocardial hypertrophy]

OBJECTIVE

To evaluate the effectiveness of two cardioplegia techniques in patients with severe myocardial hypertrophy undergoing septal myectomy or aortic valve replacement.

MATERIAL AND METHODS

A comparative pilot prospective single-center randomized study included 46 patients between 2022 and 2023. Patients were randomized into 2 groups: Del Nido (n=23) and Custodiol (n=23). We analyzed perioperative echocardiography data, troponin I at several time points, perioperative complications and histological data.

RESULTS

Both groups were comparable in time of myocardial ischemia, cardiopulmonary bypass, duration of anesthesia and surgery (p>0.05). The maximum ischemia time in the Del Nido group was 84 min. The same group showed significantly higher percentage of spontaneous rhythm recovery (65.2% vs. 30%, p=0.008). None patient required mechanical support, high-dose inotropes or vasopressors. Troponin I in 2 hours after cardiopulmonary bypass (p=0.415), 12 (p=0.528) and 24 hours after admission to the intensive care unit (p=0.281) were similar in both groups. No significant difference was found in ventilation time, ICU- and hospital-stay.

CONCLUSION

Del Nido cardioplegia has some advantages compared to Custodiol and does not lead to perioperative complications in case of aortic cross-clamping time <90 min in patients with myocardial hypertrophy.

Del Nido cardioplegia for myocardial protection in adult cardiac surgery: a systematic review and update meta-analysis

OBJECTIVE

Although the application of del Nido cardioplegia solution (DNC) in adult cardiac surgery is accumulating, the feasibility and safety of this myocardial protection strategy in adults remains controversial. We aimed to update our previous meta-analysis to determine the myocardial protective effect of DNC versus conventional cardioplegia (CC) in adult cardiac surgery.

METHODS

A comprehensive literature search was performed using PubMed, EMBASE, the Cochrane Library, and International Clinical Trials Registry Platform databases through November 2020.

RESULTS

Thirty-seven observational studies and four randomized controlled trials (RCTs) including 21,779 patients were identified. The DNC group was associated with decreased postoperative cardiac enzymes [troponin T (cTnT) and creatine kinase-MB (CK-MB)] [standardized mean differences (SMD): -0.59, 95% confidence interval (CI): -0.99 to -0.19, p = 0.004], cardiopulmonary bypass (CPB) time (MD: -9.31, 95% CI: -13.10 to -5.51, p < 0.00001), aortic cross-clamp (ACC) time (MD: -7.20, 95% CI: -10.31 to -4.09, p < 0.00001), and cardioplegia volume (SMD: -1.95, 95% CI: -2.46 to -1.44, p < 0.00001). Intraoperative defibrillation requirement was less in the DNC group [relative risk (RR): 0.50, 95% CI: 0.33 to 0.75, p = 0.0007]. The pooled analysis revealed no significant difference in operative mortality among the patients assigned to DNC and those undergoing CC.

CONCLUSION

In adult cardiac surgery, compared to CC, myocardial protection used with DNC yield similar or better short-term clinical outcomes. More high-quality trials and RCTs reflecting long-term follow-up morbidity and mortality are required in the future to confirm these findings.

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.

Del Nido versus HTK cardioplegia for myocardial protection during adult complex valve surgery: a retrospective study

BACKGROUND

Histidine-tryptophan-ketoglutarate (HTK) and del Nido (DN) cardioplegia are intracellular-type and extracellular-type solution respectively, both can provide a long period of myocardial protection with single-dose infusion, but studies comparing the two are rare for adult cardiac surgery. This study aims to evaluate whether DN is suitable for cardioplegia in complex and high-risk valve surgery with long-term cardiac ischemia when compared with HTK.

METHODS

The perioperative records of adult patients infused with DN/HTK as a cardioplegic solution who underwent complex valve surgery with an expected myocardial ischaemic duration longer than 90 min between Oct 2018 and Oct 2019 were analysed retrospectively.

RESULTS

Of the 160 patients who received DN/HTK and underwent complex valve surgery, we propensity matched 73 pairs. Both groups achieved satisfactory cardiac arrest effects, and no significant difference was found in their cTnI and CK-MB levels within 12 to 72 h postoperatively. The DN group had a higher rate of return to spontaneous rhythm (0.88 v 0.52, P < 0.001), a lower frequency of postoperative severe arrythmias (12% v 26%, P = 0.036), a higher postoperative stroke volume (65 v 59 ml, P = 0.011) and a higher cardiac output (6.0 v 4.9 L/min, P = 0.007) as evaluated by echocardiography, fewer transfusions and shorter ICU stays (both P < 0.05). The two groups had similar inotrope usage and similar incidences of low cardiac output, morbidities and mortality. Subgroup analysis showed that when the aortic clamping time was greater than 120 min, the advantages of DN were weakened.

CONCLUSIONS

DN can be safely applied to complex valve surgery, and it has a similar myocardial protection effect as HTK. Further prospective studies are required to verify these retrospective findings. Trial registration retrospectively registered.

Del Nido versus warm blood cardioplegia in adult patients with a low ejection fraction

Background

Del Nido cardioplegia was recently introduced to adult cardiac surgery with encouraging results. The effect of Del Nido cardioplegia in patients with low ejection fraction (EF) has not been thoroughly evaluated. The objective of this study was to assess the safety of Del Nido cardioplegia in adult patients with low EF compared to intermittent warm blood cardioplegia.

Results

During 2018 and 2019, 73 adult patients with an EF of ≤ 40% underwent cardiac surgery using Del Nido cardioplegia. The patients were compared to a historical cohort of consecutive patients with low EF who had intermitted warm blood cardioplegia (n = 81). Patients who had Del Nido cardioplegia had significantly lower EuroSCORE II (2.73 (1.7–4.1) vs. 4.5 (2.4–7.4), P = 0.004). There were no differences in creatinine clearance and preoperative echocardiographic data between the groups. Cardiopulmonary bypass and cross-clamp times were non-significantly lower with Del Nido cardioplegia. There were no differences in stroke and postoperative echocardiographic data between the groups. No hospital mortality was reported in both groups. Peak troponin levels were significantly higher in patients who had Del Nido cardioplegia (0.88 (0.58–1.47) vs. 0.7 (0.44–1.01) ng/dL; P = 0.01); however, after multivariable regression analysis, cardiopulmonary bypass time was the only predictor of postoperative troponin level (coefficient 0.005 (95% CI: 0.003–0.008); P < 0.001). ICU stay was significantly longer in patients who had Del Nido cardioplegia (4 (3–6) vs. 2(1–4) days, P < 0.001), while postoperative hospital stay did not differ between the groups. After multivariable regression, the use of intermittent warm blood cardioplegia was significantly associated with shorter ICU stay (coefficient − 1.80 (95% CI − 3.06 – -0.55); P = 0.01).

Conclusions

Prolonged ICU was reported with Del Nido cardioplegia; however, there were no differences in the duration of hospital stay and the clinical outcomes between the groups. Despite the proven efficacy of intermittent warm blood cardioplegia, the use of Del Nido cardioplegia might be safe in patients with low EF.

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.

Mitral valve surgery: current status and future prospects of the minimally invasive approach

Introduction: During the past five years the approach to procedural planning, operative techniques and perfusion strategies for minimally invasive mitral valve surgery (MIMVS) has evolved. With the goal to provide a maximum of patient safety the procedure has been modified according to individual patient characteristics and is largely based on preoperative imaging.Areas covered: In this review article we describe the important factors in image based therapy planning and simulation, different access strategies, the operative key-steps, a rationale use of devices, and highlight a few future developments in the field of MIMVS. Published studies were identified through pearl growing, citation chasing, a search of PubMed using the systematic review methods filter, and the authors' topic knowledge.Expert opinion: With the help of expert teams including surgeons specialized in mitral repair, anesthesiologists and perfusionists a broad spectrum of mitral valve pathologies and related pathologies can be treated with excellent functional outcomes. Avoiding procedure related complications is the key for success for any MIMVS program.

Minimally invasive mitral valve surgery

There is considerable interest and demand in the application of minimally invasive techniques in cardiac surgery driven by multiple factors including patient cosmesis and satisfaction, reduction of surgical trauma and the development of specialized instrumentation that allows these procedures to be performed safely. Minimally invasive mitral valve surgery (MIMVS) has been conducted for more than 25 years and has been shown to offer multiple benefits including better cosmetic results, enhanced post-operative recovery, improved patient satisfaction and most importantly, equivalent clinical outcomes with regards to quality and safety when compared to the standard sternotomy approach. MIMVS may be particularly beneficial in certain subgroups of patients, for example patients undergoing redo mitral valve surgery. In this article, we discuss patient selection criteria for MIMVS, the merits and drawbacks of MIMVS relative to conventional sternotomy approaches, and detail procedural aspects including anaesthetic management, intraoperative technique, and important considerations in myocardial protection and cardiopulmonary bypass (CPB). When considering developing a MIMVS programme, as for any new technique, a team approach to the introduction of the programme is essential. Although it is clear that patient selection is important, particularly early in a surgical programme, with experience complex repairs can be performed through a minimally invasive approach with excellent outcomes.

Myocardial Protection in Adult Cardiac Surgery With del Nido Versus Blood Cardioplegia: A Systematic Review and Meta-Analysis

BACKGROUND

Myocardial protection in adult cardiac surgery is commonly achieved with either multidose blood cardioplegia or single-dose del Nido crystalloid cardioplegia.

AIM

The aim of this systematic review and meta-analysis was to compare the outcomes of del Nido cardioplegia versus blood cardioplegia in adult cardiac surgery.

METHOD

All English-language articles were searched in MEDLINE (PubMed), the Cochrane Central Register of Controlled Trials (CENTRAL), and Google Scholar up to March 2020, to identify randomised control trials, prospective observational studies, and retrospective analyses (with or without propensity matching) reporting any or all of the primary and secondary endpoints. The primary endpoint was all-cause mortality. Secondary endpoints included cardiopulmonary bypass (CPB) and aortic cross-clamp (AoX) time; cardioplegia volume; need for defibrillation after AoX release; intraoperative glucose; postoperative myocardial enzyme release; postoperative left ventricular ejection fraction (LVEF); incidence of postoperative acute kidney injury (AKI), atrial fibrillation (AF), stroke, and low cardiac output syndrome (LCOS); postoperative blood transfusion; duration of mechanical ventilation; and length of intensive care unit (ICU) and hospital stay.

RESULTS

Twenty-nine (29) studies were included. There was no difference in the primary outcome of mortality between the two groups (odds ratio [OR], 1.18; 95% confidence interval [CI], 0.82-1.72 [p=0.37]). del Nido cardioplegia was associated with significantly shorter CPB (mean difference [MD], -7.42 minutes; 95% CI, -12.53 to -2.31 [p=0.004]) and AoX times (MD, -6.39 minutes; 95% CI, -10.30 to -2.48 [p=0.001]), and lower cardioplegia volumes. Significantly fewer patients required defibrillation after AoX release in the del Nido group. Intraoperative glucose homeostasis was better preserved in the del Nido group. Postoperative cardiac troponin T release and the number of patients needing transfusions were less in the del Nido group. No differences were seen in postoperative LVEF, or in the incidence of AKI, stroke, AF, and LCOS. Duration of mechanical ventilation, and length of ICU and hospital stay were similar.

CONCLUSIONS

Although this meta-analysis failed to find any mortality benefits with del Nido cardioplegia, significant benefits were seen in a number of intraoperative and postoperative variables. del Nido cardioplegia is a safe and favourable alternative to blood cardioplegia in adult cardiac surgery.

St. Thomas and del Nido cardioplegia are superior to Custodiol cardioplegia in a rat model of donor heart

OBJECTIVES

Cardiac transplantation is an effective treatment for advanced heart disease and protection of the donor organ is directly associated with post-transplantation outcomes. Cardioplegic strategies intend to protect the donor heart against ischemic injury during transplantation procedures. In our study, the effects of three different cardioplegia solutions were evaluated in a rat heart donor model in terms of cellular base. Design. Cardioplegia solutions as St. Thomas, del Nido or Custodiol were administered to male Wistar albino rats until cardiac arrest. Arrested hearts were excised and incubated in cold cardioplegia solutions for 4 h. Organ bath experiments were performed using the right ventricular free wall strips of the heart tissues. ATP, sialic acid, TNF-α levels and MMP-9 activities were measured in heart tissues. Incubation media were also used to measure TNF-α and troponin-I levels following organ baths experiments. Results. Custodiol administration led to reduced myocardial contraction (p < .05), decreased ATP levels (p < .001) and increased both TNF-α levels (p < .05), and MMP-9 activity (p < .05). Additionally, troponin-I and TNF-α levels in media were significantly increased (p < .05), TNF-α levels were positively correlated with MMP-9 activities (r = .93, p = .007) and negatively correlated with ATP levels (r = -.91, p = .01) in the Custodiol group. Also, MMP-9 activities were negatively correlated with ATP levels (r = -.90, p = .01) Conclusion. Custodiol cardioplegia cannot prevent functional and cellular damage in donor heart tissue. St. Thomas or del Nido cardioplegia could result in superior functional and biochemical improvement during transplantation procedures. In this respect, these cardioplegic solutions may be more advantageous as cellular and functional.

Clinical outcomes of single-dose cardioplegia in high-risk coronary bypass

BACKGROUND

Despite the increasing popularity of single-dose cardioplegia techniques in coronary artery bypass grafting, the time window for successful reperfusion remains unclear. This study aimed to compare different cardioplegic techniques based on early and 30-day clinical outcomes via thorough monitoring.

METHODS

This prospective cohort study included high-risk patients undergoing coronary artery bypass grafting and receiving 3 different types of cardioplegia between January 2017 and June 2019. Group 1 (n = 101) had a single dose of del Nido cardioplegia, group 2 (n = 92) had a single dose of histidine-tryptophane-ketoglutarate, and group 3 (n = 119) had cold blood cardioplegia. Patients were examined perioperatively by memory loop recording and auto-triggered memory loop recording for 30 days, with documentation of predefined events.

RESULTS

Interleukin-6 and cardiac troponin levels in group 1 were significantly higher than those in groups 2 and 3. The incidence of predefined events as markers of inadequate myocardial protection was significantly higher group 1, with more frequent atrial fibrillation attacks and more hospital readmissions. The readmission rate was 17.6% in group 1, 9% in group 2, and 8% in group 3.

CONCLUSIONS

Our data demonstrate the long-term efficacy of cardioplegic techniques, which may become more crucial in high-risk patients who genuinely have a chance to benefit from adjunct myocardial protection. Patients given del Nido cardioplegia had a significantly more prominent inflammatory response and higher troponin levels after cardiopulmonary bypass. This group had issues in the longer term with significantly more cardiac events and a higher rehospitalization rate.

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.

Excellent Restoration of Left Ventricular Compliance After Prolonged Del Nido Single-Dose Cardioplegia in an In Vivo Piglet Model

Del Nido cardioplegia (DN) is used in congenital heart surgery and recently in adults, a single dose has been administered. However, the tolerable ischemic time has not been established. The objective is to evaluate the left ventricular (LV) function recovery and accompanying biochemical and histologic markers to clarify the tolerable ischemic time in an in vivo cardiopulmonary bypass (CPB) piglet model. Twenty-one piglets were subjected to either 90 minutes (with or without topical cooling; TC) or 120 minutes (with TC) of global ischemia induced by single-dose DN, while the other 7 served as the control group (CPB only). The CPB temperature was established with a perfusion temperature of 30°C. The LV function recovery was assessed by the percent change in end-systolic elastance (Ees) and the end-diastolic pressure-volume relationship (EDPVR). Creatine kinase-MB (CK-MB) levels and the mitochondrial score were also assessed. LV contractility assessed by %Ees after 90 and 120 minutes of ischemia (89.3 ± 20.6% and 57.9 ± 17.8%) was lower compared with the control group (122.6 ± 35.8%, P = 0.001). Conversely, LV compliance assessed by %EDPVR was preserved in both groups (102.7 ± 28.2% and 88.5 ± 24.0%), which was comparable to the control group (105.8 ± 36.9%, P = 0.531). There was no change in LV contractility after 90 minutes of ischemia with or without TC (89.3 ± 20.6% or 84.8 ± 16.2%, P = 0.657), whereas LV compliance was lower but not statistically different without TC (102.7 ± 28.2% vs 78.0 ± 38.9%). CK-MB and the mitochondrial score were equivalent between all groups. The proposed single-dose ischemic time for redosing is 90 minutes using TC.

Single-dose del Nido cardioplegia used in adult minimally invasive valve surgery

Background

To analyze the protective effect of single-dose del Nido cardioplegia (DNC) in adult minimally invasive valve surgery.

Methods

From January to December 2017, 165 consecutive adult patients who underwent minimally invasive valve surgery by the same team of surgeons were divided into two cohorts based on the type of cardioplegia administered during surgery: (I) single-dose DNC (DNC group (n=76, male 41, female 35) used in patients from May to December, 2017 and (II) intermittent standard 4:1 blood cardioplegia based on St.Thomas solution (SBC group, n=89, male 45, female 44) used in patients from January to April, 2017. Preoperative baseline demographics, preoperative comorbidities, operative variables, postoperative complications, and patient outcomes were collected and compared between the two groups.

Results

Preoperative characteristics were shown to be similar between the two groups before and after propensity matching. Patients in the DNC group required a significantly lower volume of cardioplegia. The volume of ultrafiltration in the DNC group was substantially higher than that in the SBC group. The spontaneous return of heartbeat rate in the DNC group was considerably higher than that in the SBC group (97.0% vs. 78.8%, P=0.006). The Euroscore II in the DNC group was markedly lower than that in the SBC group (2.00 vs. 3.00, P<0.05). The level of blood urea nitrogen (BUN) in the DNC group was significantly lower than that in the SBC group (6.20 vs. 6.95, P<0.05). There were no differences in surgery procedure, cross-clamp time, bypass time, Apache score, troponin T (cTnT), brain natriuretic peptide (BNP), liver and renal function, postoperative complications or patient outcomes between two groups. Regression analysis showed that cTnT increased with the prolongation of myocardial ischemia time, and was closely related to the type of operation, but had no significant correlation with the type of cardioplegia.

Conclusions

In our initial experience, single-dose DNC in adult minimally invasive valve surgery in which the cross-clamp time was mostly less than 90 min, achieved equivalent myocardial protection and clinical outcomes when compared with standard whole blood cardioplegia. In addition, single-dose DNC made the minimally invasive valve surgery procedure progress in a smoother and more convenient fashion.

Comparative Effects of Blood and Crystalloid Cardioplegia on Cellular Injury and Oxidative Stress in Cardiovascular Surgery

Purpose: The purpose of this study was to evaluate the effect of different cardioplegic solutions on endothelial integrity and oxidative stress in cardiovascular surgery.

Methods: In this randomized prospective study, after ethics approval and informed consent, 60 surgical patients were included. Patients undergoing coronary bypass surgery were randomized into two groups as warm blood cardioplegia (n = 30) and cold crystalloid cardioplegia (n = 30) following the cross-clamping. Measurements were performed at three time points: before induction of anesthesia (T1), at admission to intensive care unit (ICU) (T2) and at the 24th postoperative hour (T3). Besides biochemical routine hemodynamic monitoring, patients were assessed for the sialic acid (SA), ischemic-modified albumin (IMA), advanced oxide protein products (AOPPs), total thiol (SH), and free hemoglobin (fHb) level.

Results: Neither crystalloid nor blood cardioplegia led to significant changes in the AOPPs, T-SH, and SA level (p >0.05). Crystalloid cardioplegia, however, increased IMA level compared to both baseline (p <0.01) and blood cardioplegia group (p <0.05). fHb levels were transiently increased in both groups at the second-time point (p <0.001). fHb level was lower in the crystalloid group compared to that in the other group (p <0.05) at T2.

Conclusion: Cardioplegia type creates similar effects on glycocalyx integrity. However, myocardial protection could be provided with warm blood cardioplegia.