Randomized trial of HTK versus warm blood cardioplegia for right ventricular protection in mitral surgery

Comparison of Bretschneider HTK cardioplegia solution and blood cardioplegia in terms of postoperative results in patients who underwent isolated supracoronary ascending aortic replacement

INTRODUCTION

Cardiac arrest with cardioplegia is the most common and reliable method of myocardial protection in cardiac surgery, but there is no definite consensus on the use of different types of cardioplegia. Two of the commonly used types of cardioplegia are Bretschneider histidine-tryptophan-ketoglutarate solution (Custodiol) and conventional blood cardioplegia. In this study, Custodiol solution and conventional blood cardioplegia used in patients with type A aortic dissection who underwent supracoronary ascending aortic replacement were aimed to be compared in terms of postoperative results.

METHODS

70 patients with type A aortic dissection who underwent supracoronary ascending aortic replacement in our clinic between January 2011 - October 2020 were included. Patients were divided into two groups, blood cardioplegia group (n = 48) and Custodiol group (n = 22) and they were compared regarding preoperative, perioperative and postoperative variables.

RESULTS

There was no significant difference between cardiopulmonary bypass time and cross-clamp time (p = 0.17 and p = 0.16, respectively). Mechanical ventilator weaning time, intensive care unit stay and hospital stay were shorter in Custodiol group (p = 0.04,p = 0.03 and p = 0.05, respectively). While inotropic support need was higher in the blood cardioplegia group (p = 0.001), there was no significant difference in terms of mortality, arrhythmia, neurological complications and renal complications.

CONCLUSIONS

Our results show that Custodiol cardioplegia solution may be superior to blood cardioplegia in reducing mechanical ventilation weaning period, intensive care and hospital stay, and reducing the use of inotropic agents in patients with type A aortic dissection undergoing supracoronary ascending aorta replacement.

Comparison Between Histidine-Tryptophan-Ketoglutarate Cardioplegia and Cold Blood Cardioplegia for Myocardial Protection in Tetralogy of Fallot Patients Undergoing Surgical Repair: A Randomized Clinical Trial

OBJECTIVES

This study was conducted to compare the efficacy of histidine-tryptophan-ketoglutarate (HTK) cardioplegia and cold blood cardioplegia (CBC), especially for postoperative right ventricular (RV) function after tetralogy of Fallot repair.

DESIGN

Randomized, double-blinded, parallel-group, controlled clinical trial.

SETTING

Ain Shams University Hospitals.

PARTICIPANTS

A total of 100 children (1 to 5 years old) scheduled for tetralogy of Fallot repair.

INTERVENTIONS

Patients were allocated (double-blinded 1:1 allocation ratio) to either the HTK group that received HTK cardioplegia (30 mL/kg via antegrade route) or the CBC group that received cold blood cardioplegia with blood-to-Ringer solution (4:1) in a volume of 20 mL/kg.

MEASUREMENTS AND MAIN RESULTS

The HTK group showed a statistically significant reduction of the vasoactive inotropic score on admission to the pediatric intensive care unit (13.0 ± 4.1) in comparison to the CBC group (15.5 ± 5.4), with a p value of 0.011. However, after 24 hours, the vasoactive-inotropic score was comparable. Lactate level during the first 24 hours was 6.2 ± 0.7 mmol/L in the HTK group and 6.9 ± 0.4 mmol/L in the CBC group (p < 0.0001). Serial troponin measurements were lower in the HTK group (1.49 ± 0.45) compared to the CBC group (1.69 ± 0.18) at the first 72 hours postoperatively (p = 0.005). Postoperative echocardiographic assessment of RV function by means of tricuspid annular plane systolic excursion and myocardial performance index were better in the HTK group than in the CBC grpup (p < 0.05).

CONCLUSIONS

HTK cardioplegia may offer better cardiac protection to pediatric patients undergoing tetralogy of Fallot repair than our institutional standard CBC with better recovery for the hypertrophic RV.

Comparison of Bretschneider HTK and Blood Cardioplegia (4:1): A Prospective Randomized Study

BACKGROUND

We compared the effect of intermittent blood and histidine-tryptophan-ketoglutarate (HTK) solution of Bretschneider on myocardial histopathology and perioperative outcome.

METHODS

Forty adult cardiac surgery patients were grouped into two (n = 20 for each): (1) Intermittent blood cardioplegia (IBC): had repeated cold 4:1 blood cardioplegia and (2) HTK: had a single dose of cold HTK for cardioprotection. Creatine kinase (CK)-MB, Troponin-I (cTn-I), pH, and lactate were studied in coronary sinus blood before and after aortic cross-clamping (AXC) and systemic blood at postoperative 6th, 24th, and 48th hours. Myocardial biopsy was performed before and after AXC for light microscopy. Vacuolation, inflammation, edema, and glycogen were graded semiquantitatively (from 0 to 3). The myocardial apoptotic index was evaluated via the terminal deoxynucleotidyl transferase dUTP nick end labeling.

RESULTS

There were no differences in perioperative clinical outcomes between the groups. The coronary sinus samples after AXC were more acidotic (7.15 ± 0.14 vs. 7.32 ± 0.07, p = 0.001) and revealed higher CK-MB (21.0 ± 12.81 vs. 12.60 ± 11.80, p = 0.008) in HTK compared with IBC. The HTK had significantly a higher amount of erythrocyte suspension intraoperatively compared with IBC (0.21 ± 0.53 vs. 1.68 ± 0.93 U, p = 0.001). Microscopically, myocardial edema was more pronounced in HTK compared with IBC after AXC (2.25 ± 0.91 vs. 1.50 ± 0.04, p = 0.013). While a significant increase in the apoptotic index was seen after AXC in both groups (p = 0.001), no difference was detected between the groups (p = 0.417).

CONCLUSION

IBC and HTK have a similar clinical outcome and protective effect, except for more pronounced myocardial edema and increased need for intraoperative transfusion with HTK.

Myocardial protection with phosphocreatine in high-risk cardiac surgery patients: a randomized trial

BACKGROUND

This study was conducted to test the hypothesis that phosphocreatine (PCr), administered intravenously and as cardioplegia adjuvant in patients undergoing cardiac surgery with prolonged aortic cross clamping and cardiopulmonary bypass (CPB) time, would decrease troponin I concentration after surgery.

METHODS

In this randomized, double-blind, placebo-controlled pilot study we included 120 patients undergoing double/triple valve repair/replacement under cardiopulmonary bypass in the cardiac surgery department of a tertiary hospital. The treatment group received: intravenous administration of 2 g of PCr after anesthesia induction; 2.5 g of PCr in every 1 L of cardioplegic solution (concentration = 10 mmol/L); intravenous administration of 2 g of PCr immediately after heart recovery following aorta declamping; 4 g of PCr at intensive care unit admission. The control group received an equivolume dose of normosaline.

RESULTS

The primary endpoint was peak concentration of troponin I after surgery. Secondary endpoints included peak concentration of serum creatinine, need for, and dosage of inotropic support, number of defibrillations after aortic declamping, incidence of arrhythmias, duration of Intensive Care Unit (ICU) stay, length of hospitalization. There was no difference in peak troponin I concentration after surgery (PCr, 10,508 pg/ml [IQR 6,838-19,034]; placebo, 11,328 pg/ml [IQR 7.660-22.894]; p = 0.24). There were also no differences in median peak serum creatinine (PCr, 100 µmol/L [IQR 85.0-117.0]; placebo, 99.5 µmol/L [IQR 90.0-117.0]; p = 0.87), the number of patients on vasopressor/inotropic agents (PCr, 49 [88%]; placebo, 57 [91%]; p = 0.60), the inotropic score on postoperative day 1 (PCr, 4.0 (0-7); placebo, 4.0 (0-10); p = 0.47), mean SOFA score on postoperative day 1 (PCr, 5.25 ± 2.33; placebo, 5,45 ± 2,65; p = 0.83), need for defibrillation after declamping of aorta (PCr, 22 [39%]; placebo, 25 [40%]; p = 0.9),, duration of ICU stay and length of hospitalization as well as 30-day mortality (PCr, 0 (0%); placebo,1 (4.3%); p = 0.4).

CONCLUSION

PCr administration to patients undergoing double/triple valve surgery under cardiopulmonary bypass is safe but is not associated with a decrease in troponin I concentration. Phosphocreatine had no beneficial effect on clinical outcomes after surgery.

TRIAL REGISTRATION

The study is registered at ClinicalTrials.gov with the Identifier: NCT02757443. First posted (published): 02/05/2016.

Coronary artery bypass grafting in left ventricular dysfunction: when and how

PURPOSE OF REVIEW

The surgical management of patients undergoing coronary artery bypass grafting (CABG) with low ejection fraction presents unique challenges that require meticulous attention to details and good surgical technique and judgement. This review details the latest evidence and best practices in the care of such patients.

RECENT FINDINGS

CABG in patients with low ejection fraction carries a significant risk of perioperative mortality and morbidity related to the development of postcardiotomy shock. Preoperative optimization with pharmacological or mechanical support is required, especially in patients with cardiogenic shock. Rapid and complete revascularization is what CABG surgeons aim to achieve. Multiple arterial revascularization should be reserved to selected patients. Off-pump CABG, on-pump breathing heart CABG, and new cardioplegic solutions remain of uncertain benefit compared with traditional CABG.

SUMMARY

Tremendous advancements in CABG allowed surgeons to offer revascularization to patients with severe left ventricular dysfunction and multivessel disease with acceptable risk. Despite that, there is a lack of comprehensive and robust studies particularly on long-term outcomes. Individualized patient assessment and a heart team approach should be used to determine the optimal surgical strategy for each patient.

An infant with suspected missed diagnosis of Williams syndrome failed weaning off CPB after surgical correction of pulmonary stenosis: a case report and literature review

Williams syndrome (WS) is a rare congenital developmental disorder caused by the deletion of between 26 and 28 genes on chromosome 7q11.23. For patients with WS, in view of the particularity of the supravalvular aortic stenosis, choosing appropriate arterial cannula, maintaining higher perfusion pressure as well as strengthening myocardial protection during cardiopulmonary bypass (CPB) is essential to the clinical outcome. Here, we report a child with pulmonary artery valvular stenosis who failed to wean off CPB because of malignant arrhythmias and cardiac insufficiency after surgical correction of pulmonary valvular stenosis. With the assistance of extracorporeal membrane oxygenation (ECMO), emergency cardiac catheterization revealed supravalvular aortic stenosis (SVAS), which suggests a suspected missed diagnosis of WS. Finally, under the support of ECMO, the cardiac function gradually returned to normal, and the child was discharged 23 days after surgery.

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.

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

Background

Surgical procedures in the heart requires protection of the heart from ischemia–reperfusion injury. Cardioplegia is the primary myocardial protective method in use. Histidine–tryptophan–ketoglutarate (HTK) solution is an intracellular cardioplegic solution that was initially used to preserve organs for transplantation.

Methods

A systematic electronic search was conducted in July 2021, in four databases; PubMed, Scopus, Web of Science, and Cochrane Library for eligible randomized controlled trials. The results were screened and the eligible trials were identified. Thereafter, the relevant data were extracted and pooled as mean difference or risk ratio, and 95% confidence interval in an inverse variance method using RevMan software.

Results

This review included 12 trials (n = 1327). HTK solution has resulted significantly in shorter intensive care unit stay (MD = − 0.09; 95% CI [− 0.15, − 0.03], p = 0.006), and shorter hospital stay (MD = − 0.51; 95% CI [− 0.71, − 0.31], p < 0.00001). Moreover, the patients who received the HTK solution had significantly lower levels of creatine kinase (after 4–7 h (MD = − 157.52; 95% CI [− 272.31, − 42.19], p = 0.007), and 24 h (MD = − 136.62; 95% CI [− 267.20, − 6.05], p = 0.04)), as well as creatine kinase muscle brain band (after 44–48 h (MD = − 3.35; 95% CI [− 5.69, − 1.02], p = 0.005)).

Conclusion

HTK solution had the same efficacy and safety as other cardioplegic solutions in most of the clinical parameters. Furthermore, the solution showed superiority in fastening the recovery and protecting the myocardium at the biochemical level. HTK solution provides longer myocardial protection; therefore, it limits surgical interruption. HTK solution can be used as an alternative to the currently used cardioplegic solutions.

Comparable prognosis in different neonatal histidine-tryptophan-ketoglutarate dosage management

Background:

Histidine-tryptophan-ketoglutarate (HTK) is a solution commonly used for organ transplantation. However, there is no certified fixed regimen for on-pump heart surgery in neonates. We aimed to retrospectively evaluate the outcomes related to different HTK dosages and to analyze the safety of high-dosage perfusion.

Methods:

A total of 146 neonates who underwent on-pump heart surgery with single-shot HTK perfusion were divided into two groups according to HTK dosages: a standard-dose (SD) group (n = 63, 40 mL/kg < HTK ≤ 60 mL/kg) and a high-dose (HD) group (n = 83, HTK >60 mL/kg). Propensity score matching (PSM) was performed to control confounding bias.

Results:

The SD group had a higher weight (3.7 ± 0.4 vs. 3.4 ± 0.4 kg, P < 0.0001), a lower proportion of complete transposition of the great artery (69.8% vs. 85.5%, P = 0.022), a lower cardiopulmonary bypass (CPB) time (123.5 [108.0, 136.0] vs. 132.5 [114.8, 152.5] min, P = 0.034), and a lower aortic x-clamp time (82.9 ± 27.1 vs. 95.5 ± 26.0 min, P = 0.005). After PSM, 44 patients were assigned to each group; baseline characteristics and CPB parameters between the two groups were comparable. There were no significant differences in peri-CPB blood product consumption after PSM (P > 0.05). The incidences of post-operative complications were not significantly different between the two groups. There were no significant differences in ventilation time, intensive care unit stay, and post-operative hospital stay (P > 0.05). Follow-up echocardiography outcomes at 1 month, 3 to 6 months, and 1 year showed that left ventricular ejection fraction and end-diastolic dimension were comparable between the two groups.

Conclusions:

In neonatal on-pump cardiac surgery patients, single-shot HD (>60 mL/kg) HTK perfusion had a comparable heart protection effect and short-term post-operative prognosis as standard dosage perfusion of 40 to 60 mL/kg. Thus, this study provides supporting evidence of the safety of HD HTK perfusion.

Warm versus cold cardioplegia in cardiac surgery: A meta-analysis with trial sequential analysis

Objective

This meta-analysis aimed to compare clinical outcomes of warm and cold cardioplegia in cardiac surgeries in adult patients, with trial sequential analysis (TSA) used to determine the conclusiveness of the results.

Methods

Electronic searches were performed on PubMed, Medline, Scopus, EMBASE, and Cochrane library to identify all studies that compared warm and cold cardioplegia in cardiac surgeries. Primary end points were in-hospital or 30-day mortality, myocardial infarction, low cardiac output syndrome, intra-aortic balloon pump use, stroke, and new atrial fibrillation. Secondary end points were acute kidney injury, hospital length of stay, and intensive care unit length of stay. Prespecified subgroup analyses were performed for (1) studies published since publication of Fan and colleagues in 2010, (2) randomized controlled studies, (3) studies with low risk of bias, (4) coronary artery bypass graft surgeries, and (5) studies with cold blood versus those with cold crystalloid cardioplegia. TSA was performed to determine conclusiveness of the results, using on all outcomes without significant heterogeneity from studies of low risk of bias.

Results

No significant differences were found between post-operative rates of mortality, myocardial infarction, low cardiac output syndrome, intra-aortic balloon pump use, stroke, new atrial fibrillation, and acute kidney injury between warm and cold cardioplegia. TSA concluded that current evidence was sufficient to rule out a 20% relative risk reduction in these outcomes.

Conclusions

Concerning safety outcomes, current evidence suggests that the choice between warm and cold cardioplegia remains in the surgeon's preference.

Guidelines for enhanced recovery after cardiac surgery. Consensus document of Spanish Societies of Anesthesia (SEDAR), Cardiovascular Surgery (SECCE) and Perfusionists (AEP)

The ERAS guidelines are intended to identify, disseminate and promote the implementation of the best, scientific evidence-based actions to decrease variability in clinical practice. The implementation of these practices in the global clinical process will promote better outcomes and the shortening of hospital and critical care unit stays, thereby resulting in a reduction in costs and in greater efficiency. After completing a systematic review at each of the points of the perioperative process in cardiac surgery, recommendations have been developed based on the best scientific evidence currently available with the consensus of the scientific societies involved.

HTK versus multidose cardioplegias for myocardial protection in adult cardiac surgery: A meta-analysis

BACKGROUND

Histidine-tryptophan-ketoglutarate (HTK) cardioplegia for myocardial protection obviates the need for maintenance cardioplegia doses, and thus allows for greater focus on procedure accuracy. The aim of this meta-analysis is to evaluate the safety and efficacy of HTK versus multidose cardioplegias during cardiac surgery in an adult population.

METHODS

Electronic searches were performed using PubMed, Science Direct, and Google Scholar databases. The key search terms included HTK cardioplegia AND cardiac surgery AND adult. This was followed by a meta-analysis investigating cardiopulmonary bypass (CPB) duration, cross-clamp duration, spontaneous defibrillation, inotropic support, mortality, atrial fibrillation, creatine kinase muscle brain band (CK-MB) and troponin I (TnI).

RESULTS

Seven randomized controlled trials (n = 804) were analyzed. Spontaneous defibrillation following aortic cross-clamp removal significantly favored HTK (odds ratio [OR], 2.809; 95% confidence interval [CI], 1.574 to 5.012; I²  = 0%; p < .01). There were no other notable significant differences between HTK and multidose cardioplegia in any of the parameters measured. In particular, the OR for mortality was 1.237 (95% CI, 0.385 to 3.978; I²  = 0%; p = .721) and the mean difference for CPB duration overall was 2.072 min (95% CI, -2.405 to 6.548; I²  = 74%; p = .364).

CONCLUSION

HTK is safe and effective during adult cardiac surgery when compared with multidose cardioplegias for myocardial protection during surgical correction of acquired pathology in the adult population. HTK may, therefore, be suitable for complex cases or those of extensive duration, without the prospect of increased postoperative morbidity or mortality.

Long-Term Protective Effects of Single-Dose Cardioplegic Solutions in Cell Culture Models

Despite the popularity of single-dose cardioplegic techniques, the time window and targeted population for successful reperfusion remain unclear. We tested currently available techniques based on cell viability and integrity to demonstrate long-term cardioprotection and clarify whether these solutions were performed on neonatal/adult endothelium and myocardium by examining different cell lines. Cell viability with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test proliferation assay and membrane integrity with the lactic dehydrogenase (LDH) cytotoxicity test were documented in a cell culture/microscopy setting on adult (human umbilical vein endothelium [HUVEC]), neonatal (H9C2-cardiomyocytes), and myofibroblast (L929) cell lines. Apoptotic cell activity and necrosis were evaluated by acridine orange/propidium iodide (AO/PI) staining. Twenty-four hours after seeding, cells were incubated in control (Dulbecco's modified Eagle), St. Thomas and blood cardioplegia (4:1), histidine-tryptophan-ketoglutarate (HTK), and del Nido solutions at 32°C followed by an additional 6, 24, and 48 hours in standard conditions (37°C, 5% CO2). Experiments were repeated eight times. In MTT cell viability analysis, HTK protection was significantly better than the control medium in L929 cell lines at 48th hours follow-up and acted markedly better on the HUVEC cell line at 24th and 48th hours. del Nido and HTK provided significantly better protection on H9C2 (at 24th and 48th hours). Apoptotic and necrotic cell scoring as a result of AO/PI staining was found consistent with MTT results. The LDH test demonstrated that the level of cell disruption was significantly higher for St. Thomas and blood cardioplegia in H9c2 cells. Experimental studies on cardioplegia aimed at assessing myocardial protection use time-consuming and often expensive approaches that are unrealistic in clinical practice. We have focused on identifying the most effective cell types and the direct consequences of different cardioplegia solutions to document long-term effects that we believe are the most underestimated ones in the cardioplegia literature.

Comparison between the Effects of Bretschneider's HTK Solution and Cold Blood Cardioplegia on Systemic Endothelial Functions in Patients who Undergo Coronary Artery Bypass Surgery: a Prospective Randomized and Controlled Trial

Objective

To investigate the effects of Bretschneider’s histidine-tryptophan-ketoglutarate (HTK) solution and cold blood cardioplegia on systemic endothelial functions.

Methods

A total of 50 patients who underwent isolated coronary artery bypass surgery between March 2018 and May 2018 were randomly divided into two groups - group 1 (Bretschneider’s HTK solution, n=25) and group 2 (cold blood cardioplegia, n=25). Data related to the indicators of endothelial dysfunction were recorded. Flow-mediated dilation was measured together with the assessment of the values of endothelin-1, von Willebrand factor, and asymmetric dimethylarginine to identify endothelial dysfunction. Then, the two groups were compared regarding these values.

Results

The most significant result of our study was that the endothelin-1 level was significantly higher in group 2 than in group 1 (P<0.001). The value of flow-mediated dilation was found to increase to a lesser degree on the postoperative days compared to the value at the day of admission in group 1 (P=0.002 and P=0.030, respectively).

Conclusion

Cardiopulmonary bypass leads to endothelial dysfunction. Our results revealed that Bretschneider’s HTK solution causes less severe endothelial injury than cold blood cardioplegia.

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.

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.

Is cold blood cardioplegia absolutely superior to cold crystalloid cardioplegia in aortic valve surgery?

BACKGROUND

Experimental evidence suggests that blood cardioplegia (BCP) may be superior to cold crystalloid cardioplegia (CCP) for myocardial protection. However, robust clinical data are lacking. We compared postoperative outcome of patients undergoing aortic valve replacement (AVR) using cold anterograde-retrograde intermittent BCP versus anterograde (CCP).

METHODS

Adult consecutive isolated AVR performed between April 2006 and February 2011 at the Royal Infirmary Hospital of Edinburgh were retrospectively analyzed. The use of anterograde CCP was compared with that of intermittent anterograde-retrograde cold BCP. End points were intra-operative mortality, 30-day hospital re-admission, need for RBC or platelet transfusion, mechanical ventilation time and renal failure.

RESULTS

Of total 774 cases analyzed, 592 cases of BCP and 182 cases of CCP were identified. Demographics did not differ between groups (mean age: 67±12 years in CCP and 69±12 years in BCP). Groups (BCP vs. CCP) were indistinguishable (P>0.05, not significant) based on: average aortic cross clamp time 77.01±14.47 vs. 75.78±18.78 minutes, cardiopulmonary bypass time 104.07±43.70 vs. 100.34±25.90 minutes, surgery time 190.53±61.80 vs. 204.04±51.09 minutes and postoperative total blood consumption 1.38±2.11 vs. 1.61±2.4 units. The percentage of patients who required platelets' transfusion was similar: 12.8% BCP and 18.7% CCP (Fisher's exact test, P=0.053). Prevalence of respiratory failure was lower in BCP than in CCP: 2.6% vs. 6.3% (P=0.028). Admission time (days) at ICU was 3.63± 21.90 in BCP and 3.07±8.04 in CCP (not significant). Intra-hospital mortality, 30-day hospital re-admission, renal failure, sepsis, wound healing and stroke did not differ between groups.

CONCLUSIONS

BCP was strictly not superior to CCP in every aspect. In particular it was definitely not superior in terms of postoperative ventricular function. Our results question the absolute superiority of BCP over CCP in terms of hard outcomes. Likelihood of serious complications should be considered to improve risk profile of patients before choosing a cardioplegic solution.

Custodiol for myocardial protection and preservation: a systematic review

INTRODUCTION

Custodiol cardioplegia is attractive for minimally invasive cardiac surgery, as a single dose provides a long period of myocardial protection. Despite widespread use in Europe, there is little data confirming its efficacy compared with conventional (blood or crystalloid) cardioplegia. There is similar enthusiasm for its use in organ preservation for transplant, but also a lack of data. This systematic review aimed to assess the evidence for the efficacy of Custodiol in myocardial protection and as a preservation solution in heart transplant.

METHODS

Electronic searches were performed of six databases from inception to October 2013. Reviewers independently identified studies that compared Custodiol with conventional cardioplegia (blood or extracellular crystalloid) in adult patients for meta-analysis; large case series that reported results using Custodiol were analyzed. Next, we identified studies that compared Custodiol with other organ preservation solutions for organ preservation in heart transplant.

RESULTS

Fourteen studies compared Custodiol with conventional cardioplegia for myocardial protection in adult cardiac surgery. No difference was identified in mortality; there was a trend for increased incidence of ventricular fibrillation in the Custodiol group that did not reach statistical significance. No difference was identified in studies that compared Custodiol with other solutions for heart transplant.

CONCLUSIONS

Despite widespread clinical use, the evidence supporting the superiority of Custodiol over other solutions for myocardial protection or organ preservation is limited. Large randomised trials are required.