Comparison of del Nido and St Thomas Cardioplegia Solutions in Pediatric Patients: A Prospective Randomized Clinical Trial

Management of a Rare Case of Multiple Coronary Artery Fistulas Associated with Ascending Aortic and Root Aneurysm: Case Report and Review of Literature

Coronary artery fistulas draining into the left ventricle is a rare finding. They can be associated with other congenital cardiac anomalies like ventricular septal defect or tetralogy of Fallot. While most of them are asymptomatic, they can lead to severe cardiac complications like infective endocarditis, heart failure, or myocardial ischemia. Symptomatic coronary artery fistulas can be managed surgically or percutaneously. We present a case of a 61-year-old male patient with both left anterior descending artery and right coronary artery fistulas draining into the left ventricle associated with ascending aorta and root aneurysm. Preoperative assessment for myocardial ischemia and the size and location of the fistulas was performed. The echocardiography stress test was negative. Surgery consisted of replacement of the ascending aorta and reconstruction of the noncoronary sinus with a Dacron patch with aortic valve preservation and no intervention for the coronary artery fistulas. The surgical strategy was adapted for cardioplegia administration to compensate for the volume of coronary blood drained into the left ventricle and for better protection of the distal myocardium.

Redosing of long acting cardioplegic solutions in adult cardiac surgery: A comparative study

INTRODUCTION

Despite promising results regarding using long-acting cardioplegia in the adult population, little data exists specifically for operations requiring prolonged aortic cross-clamp needing additional doses. In this pilot study, we evaluated the outcomes of patients undergoing surgery with prolonged cross-clamp time based on four different redosing compositions.

METHODS

During the period from January 2019 until June 2022, 288 patients undergoing cardiac surgery with an expected cross-clamp time over 60 min were prospectively randomized regarding the type of the cardioplegia used: Group 1 (N = 150)- single-dose del Nido antegrade cardioplegia and Group 2 (N = 138)- single-dose Histidine-Tryptophane-Ketoglutarate (HTK) antegrade cardioplegia. In patients with ischemic time over 60 min, needing a redosing were further analyzed separately in four subgroups: (A) Cold whole blood (CWB) (4:1) (N = 95); (A1: DN-CWB; A2: HTK-CWB) and (B) St Thomas Solution (N = 92) (B1: DN-St Thomas; B2: HTK-St Thomas. Control groups were C1 (DN redosed by DN) and C2 (HTK by HTK).

RESULTS

Troponin levels in A1 and B1 groups were significantly lower than in DN-control. Respiratory support time and incidence of atrial fibrillation were significantly lower in Group A1 versus DN-control.

CONCLUSIONS

Long-acting cardioplegic techniques are becoming widely utilized in the adult population, with minimal data on redosing methods/compositions for prolonged cases. Due to the small patient population, further investigation is needed to delineate optimal redosing methods, but this report brings to attention the initial success of multiple strategies.

Which is better for pediatric and adult cardiac surgery: del Nido or St. Thomas cardioplegia? A systematic review and meta-analysis

Background

Although recently it has been extended for use in adult cardiac surgery, del Nido cardioplegia was originally indicated for pediatric cardiac surgery. In this meta-analysis, we compare del Nido cardioplegia vs St. Thomas cardioplegia in pediatric and adult cardiac surgery.

Methods

A comprehensive systematic literature review was performed to identify observational and randomized controlled trials (RCTs) comparing del Nido cardioplegia with St. Thomas cardioplegia. An analysis of both random and fixed effects was conducted. The measure of the effect was by the mean difference (MD) and the risk ratio (RR) with a 95% confidence interval (95% CI).

Results

A total of 1893 patients from 12 studies were included (5 RCTs and 7 observational studies). Compared to St. Thomas solution, del Nido cardioplegia was associated with a shorter aortic cross-clamp in adult cardiac surgery (RCT MD - 19.83, 95% CI - 21.89-17.78; observational - 5.85; 95% CI - 11.59, - 0.11 respectively), but no difference in pediatric cardiac surgery. Additionally, del Nido cardioplegia was associated with lower cardiopulmonary bypass time in both adults (observational, MD - 29.15; 95% CI - 31.76-26.55) and pediatric cardiac surgery (RCTs, MD - 7.15; 95% CI - 13.25-1.05). Defibrillation rates were also significantly lower with del Nido cardioplegia group in both adult (RR 0.35, 95% CI 0.24-0.50, I2 = 50%) and pediatric cardiac surgery (odds ratio (OR) 0.30, 95% CI 0.18-0.49, I2 = 92%).

Conclusion

In both adults and pediatric cardiac surgery, del Nido cardioplegia helps in lowering cardiopulmonary bypass duration, defibrillation rates, and hospital stay, compared to St. Thomas solution. Among adults, del Nido cardioplegia lessens the aortic cross clamp times with no difference observed in all-cause mortality, intensive care unit stay, or mechanical ventilation.

Open-heart surgery using Del-Nido cardioplegia in two dogs: partial atrioventricular septal defect and mitral repair

Del-Nido cardioplegia (DNc) is a single-dose cardioplegia that is widely used in human medicine because of its long duration. In this report, we describe two cases of open-heart surgery with cardiopulmonary bypass (CPB) using DNc. One dog was diagnosed with partial atrioventricular septal defect, and the other dog was diagnosed with myxomatous mitral valve disease stage D. Both dogs were treated with open-heart surgery with DNc to induce temporary cardiac arrest. No complications from DNc were observed, and the patients were discharged. Veterinary heart surgeons should consider DNc as an option for temporary cardiac arrest during open-heart surgery with CPB.

Comparison between Del Nido and conventional blood cardioplegia in pediatric open-heart surgery

BACKGROUND

Del Nido cardioplegia (DNc) was designed for superior myocardial protection during cardiopulmonary bypass (CPB). We conducted a retrospective review to explore if DNc was associated with increase in systemic ventricle dysfunction (sVD) following pediatric CPB.

METHODS AND RESULTS

This single-center, retrospective study included 1534 patients undergoing CPB between 2013 and 2016, 997 prior to center-wide conversion to DNc and 537 following. The primary outcome was new postoperative ≥moderate sVD by echocardiogram. Secondary outcomes included sVD of any severity and right ventricular dysfunction. Data was evaluated by interrupted time-series analysis. Groups had similar cardiac diagnoses and surgical complexity. Del Nido cardioplegia was associated with longer median (IQR) CPB [117 (84-158) vs 108 (81-154), p = 0.04], and aortic cross-clamp [83 (55-119) vs 76 (53-106), p = 0.03], and fewer cardioplegia doses [2 (1-2) vs 3 (2-4), p < 0.0001]. Mortality was similar in both groups. Frequency of sVD was unchanged following DNc, including predetermine subgroups (neonates, infants, and prolonged cross-clamp). Logistic regression showed a significant rise in right ventricular dysfunction (OR 5.886 [95% CI: 0.588, 11.185], p = 0.03) but similar slope.

CONCLUSIONS

Use of DNc was not associated with increased in reported sVD, and provided similar myocardical protection to the systemic ventricle compared to conventional cardioplegia but may possibly impact right ventricular function. Studies evaluating quantitative systolic and diastolic function are needed.

Cardioplegia in Open Heart Surgery: Age Matters

INTRODUCTION

Cardioplegia is a pharmacological approach essential for the protection of the heart from ischemia-reperfusion (I-R) injury. Over the years, numerous cardioplegic solutions have been developed, with each cardioplegic approach having its advantages and disadvantages. Cardioplegic solutions can be divided into crystalloid and blood cardioplegic solutions, and an experienced surgeon chooses the type of solution based on the individual needs of patients in order to provide optimal heart protection. Importantly, the pediatric immature myocardium is structurally, physiologically, and metabolically different from the adult heart, and consequently its needs to achieve cardioplegic arrest strongly differ. Therefore, the present review aimed to provide a summary of the cardioplegic solutions available to pediatric patients with a special focus on emphasizing differences in heart injury after various cardioplegic solutions, the dosing strategies, and regimens.

MATERIAL AND METHODS

The PubMed database was searched using the terms cardioplegia, I-R, and pediatric population, and studies that investigated the influence of cardioplegic strategies on markers of cardiac muscle damage were further analyzed in this review.

CONCLUSIONS

A large body of evidence suggested more prominent benefits achieved with blood compared to those with crystalloid cardioplegia in pediatric myocardium preservation. However, standardized and uniform protocols have not been established so far, and an experienced surgeon chooses the type of cardioplegia solution based on the individual needs of patients, while the severity of myocardial damage strongly depends on the type and duration of the surgical procedure, overall patient condition, and presence of comorbidities, etc.

Plasmalyte-A Based del Nido Cardioplegia Versus Plain Ringer Based del Nido Cardioplegia: Double-Blind Randomized Trial

Background: In this prospective randomized controlled trial, we compared the standard del Nido cardioplegia solution (SDN) with the modified del Nido cardioplegia solution (MDN) in which the base solution was the plain Ringer solution. Methods: A total of 80 patients aged < 12 years undergoing intracardiac repair of Tetralogy of Fallot were randomized into SDN (n = 39) or MDN (n = 41) groups. The primary outcome was a change in cardiac index (CI). Secondary outcomes were ventricular arrhythmias after the release of aortic-cross clamp, postoperative inotropic score (IS), time to peripheral rewarming, duration of mechanical ventilation, intensive care unit (ICU) length of stay, and hospital length of stay, and electron microscopic differences between the 2 groups. Cardiac Troponin-I, inflammatory markers tumor necrosis factor-α (TNF-α), and interleukin-L (IL-6) were measured. Results: Applying the noninferiority confidence interval approach, the difference between the changes in CI between the 2 groups was -0.093 L/min/m2 (95% CI: -0.46-0.27 L/min/m2) which was within the noninferiority threshold of -0.5 indicating that CI was similar in both SDN and MDN. Ventricular arrhythmias postclamp release (P = .91), IS (P = .09), duration of mechanical ventilation (P = .27), ICU length of stay (P = .50), hospital length of stay (P = .57), IL-6 (P = .19), TNF-α (P = .17), Troponin-I (P = .15), electron microscopy changes (P > .05) were not different between groups. Conclusion: MDN was shown to be noninferior to the SDN cardioplegia in terms of preservation of cardiac index. In addition, other metrics indicative of myocardial protection were similar between groups. In developing nations where SDN is not available or is expensive, MDN cardioplegia is an acceptable alternative.

High-sensitivity cardiac troponins in pediatric population

Apparently healthy children often complain of chest pain, especially after physical exercise. Cardiac biomarker levels are often measured, but the clinical relevance of these assays in children is still debated, even when a cardiac disease is present. Coronary artery disease is exceedingly rare in children, but elevated circulating levels of cardiac troponin I (cTnI) and T (cTnT) in an acute setting may help detect heart failure due to an unknown cardiac disorder, or worsening heart failure, particularly in combination with other biomarkers such as B-type natriuretic peptides. However, the interpretation of biomarkers is often challenging, especially when institutions transition from conventional cTn assays to high-sensitivity (hs-cTn) methods, as well demonstrated in the emergency setting for adult patients. From a clinical perspective, the lack of established reference values in the pediatric age is the main problem limiting the use of hs-cTn methods for the diagnosis and managements of cardiac diseases in infants, children and adolescents. This review aims to discuss the possibility to use hs-cTnI and hs-cTnT to detect cardiac disease and to explore age-related differences in biomarker levels in the pediatric age. We start from some analytical and pathophysiological considerations related to hs-cTn assays. Then, after a systematic literature search, we discuss the current evidence and possible limitations of hs-cTn assay as indicators of cardiac disease in the most frequently cardiac disease in pediatric setting.

Clinical outcomes of del nido cardioplegia and st thomas blood cardioplegia in neonatal congenital heart surgery

Objectives:

Cardioplegia is essential for adequate myocardial protection. There continues to remain ambiguity regarding the ideal cardioplegia for adequate myocardial protection in congenital heart surgery. This study compares clinical outcomes using St Thomas II solution and Del Nido cardioplegia in neonates undergoing cardiac surgery.

Methods:

All neonates (<30 days) from 2011 to 2017 who underwent surgery requiring cardioplegic arrest were analyzed retrospectively. We divided the cohort into two groups depending on cardioplegia received, as group A (Blood cardioplegia with St Thomas II solution, n = 56) and group B (Del Nido cardioplegia, n = 48). Various demographic, intraoperative, early postoperative, and discharge variables were analyzed.

Results:

Two groups were similar in age, gender, pre-operative diagnosis, and risk category. Cardiopulmonary bypass (CPB) time (P = 0.002), aortic cross-clamp (ACC) time (P = 0.018), and the number of doses of cardioplegia (P < 0.001) were significantly lower with Del Nido group. Though vasoactive inotropic score (VIS) (P = 0.036) was high during the first 24 h in the immediate postoperative period in group A, there was no difference in early mortality among both groups (P = 0.749). Both groups did not show significant differences related to various postoperative and discharge variables.

Conclusion:

When compared to St. Thomas solution, the use of Del Nido cardioplegia solution in neonates is associated with a significant decrease in CPB and ACC times and VIS in the first 24 h after surgery. The choice of cardioplegia (St Thomas/Del Nido) in neonates does not affect early mortality and early postoperative clinical outcomes.

Modified del Nido versus blood cardioplegia in congenital cardiac surgery

BACKGROUND

Lactated Ringer-based del Nido cardioplegia has been reported to be safe for acquired cardiac surgery. The original Plasma-Lyte-based solution has been proved for congenital cardiac surgery but its modification has not been adequately examined. We compared the clinical outcomes of congenital cardiac surgery using lactated Ringer-based del Nido cardioplegia versus cold blood cardioplegia.

METHODS

Between September 2018 and November 2020, 116 consecutive patients with congenital heart disease undergoing operations with cardioplegic arrest performed by a single surgeon at Faculty of Medicine Siriraj hospital; 66 with modified del Nido solution and 50 with institutional's blood cardioplegia. The patient risk profiles, operative details, mortality rates, care durations, inotrope use, blood transfusion and complications were compared.

RESULTS

Preoperative characteristics were similar between groups, including median age (2.5 vs. 3.1 years; p = 0.49), size, and gender. The Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery score of 3 to 5 was more prevalent in the del Nido group (24.2% vs. 10%; p = 0.049). There were 4 deaths in the modified del Nido group (risk category score of 4) but none in the cold blood group (p = 0.13). There was no significant difference in median intubation duration, length of intensive care unit stay, and vasoactive medications immediately and 24 h after the operation. The del Nido group required 70 to 100 ml less blood transfusion (p = 0.04). All complications were similar between the two groups.

CONCLUSIONS

Clinical outcomes of lactated Ringer-based del Nido cardioplegia were comparable to those of blood cardioplegia in congenital cardiac surgery.

Initial experience with del Nido cardioplegia solution at a Pediatric and Congenital Cardiac Surgery Program in Brazil

OBJECTIVE

The aim of this study was to evaluate outcome measures between our standard multidose cardioplegia protocol and a del Nido cardioplegia protocol in congenital heart surgery patients.

METHODS

Retrospective single-center study including 250 consecutive patients that received del Nido cardioplegia (DN group) with a mandatory reperfusion period of 30% of cross clamp time and 250 patients that received a modified St. Thomas' solution (ST group). Groups were matched by age, weight, gender, and Risk Adjustment for Congenital Heart Surgery (RACHS-1) scores. Preoperative hematocrit and oxygen saturation were also recorded. Outcomes analyzed were the vasoactive inotropic score (VIS), lactate, ventilation time, ventricular dysfunction with low cardiac output syndrome (LCOS), intensive care unit (ICU) length of stay (LOS), hospital LOS, bypass and aortic cross-clamp times, and in-hospital mortality.

RESULTS

Both groups were comparable demographically. Statistically significant differences (p ⩽ 0.05) were noted for cardiac dysfunction with LCOS, hematocrit at end of surgery (p = 0.0038), VIS on ICU admission and at end of surgery (p = 0.0111), and ICU LOS (p = 0.00118) with patients in the DN group having more desirable values for those parameters. Other outcome measures did not reach statistical significance.

CONCLUSION

In our congenital cardiac surgery population, del Nido cardioplegia strategy was associated with less ventricular dysfunction with LCOS, a lower VIS and decreased ICU LOS compared with patients that received our standard myocardial protection using a modified St. Thomas' solution. Despite the limitation of this study, including its retrospective nature and cohort size, these data supported our transition to incorporate del Nido cardioplegia solution with a mandatory reperfusion period as the preferred myocardial protection method in our program.

Single-Dose del Nido Cardioplegia Compared With Standard Cardioplegia During Coronary Artery Bypass Grafting at a Veterans Affairs Hospital

Del Nido cardioplegic solution (DNC), used chiefly in pediatric patients, rapidly induces prolonged cardiac arrest during cardiac surgery. To determine whether surgical outcomes after coronary artery bypass grafting in a United States military veteran population differed when DNC was used instead of our standard Plegisol cardioplegia, we retrospectively reviewed 155 consecutive operations performed from July 2016 through June 2017. Del Nido cardioplegia was used to induce cardiac arrest in 70 patients, and Plegisol in 85. Compared with the Plegisol group, the DNC group had a shorter mean cardiopulmonary bypass time (96.8 vs 117 min; P <0.01) and aortic cross-clamp time (63.9 vs 71.7 min; P=0.02). On multiple linear regression, DNC use and number of bypasses performed were predictors of cardiopulmonary bypass time. The groups were similar in median number of bypasses performed, median time to extubation, intensive care unit stay, and total postoperative stay; however, the DNC group had a shorter mean operating room time (285.8 vs 364.5 min; P <0.01). Del Nido cardioplegia, number of bypasses, cardiopulmonary bypass time, and red blood cell transfusion were predictors of operating room time. Outcomes in the groups were similar for 30- and 180-day death, stroke, renal failure, ventilation time >48 hours, atrial fibrillation, tracheostomy, reintubation, and mechanical circulatory support. We conclude that single-dose DNC is safe, effective, and cost-effective for achieving cardiac arrest in U.S. veteran populations.

International Pediatric Perfusion Practice: 2016 Survey Results

New cardiopulmonary bypass device techniques emerge and are reported in the scientific literature. The extent to which they are actually adopted into clinical practice is not well known. Since 1989, we have periodically surveyed pediatric cardiac centers to ascertain practice patterns. In December 2016, a 186-question perfusion survey was distributed to pediatric cardiac surgery centers all over the world using a Web-based survey tool. Responses were received from 93 North American (NA) centers (the United States and Canada) and 67 non-NA (NNA) centers, representing 19,645 cumulative annual procedures in NA and 27,776 in NNA centers on patients <18 years. Wide variation in practice was evident across geographic regions. However, the most common pediatric circuit consisted of a hard-shell (open) venous reservoir, an arterial roller pump, and a hollow-fiber membrane oxygenator with a separate or integrated arterial filter. Compared with our previous surveys, there was increased utilization of all types of safety devices. The use of an electronic perfusion record was reported by 50% of NA centers and 31% of NNA centers. There was wide regional variation in cardioplegia delivery systems and cardioplegia solutions. Seventy-nine percent of the centers reported the use of some form of modified ultrafiltration. The survey demonstrated that there remains variation in perfusion practice for pediatric patients. Future surveys will be useful to evaluate the adoption of emerging perfusion practice guidelines.

Comparison of del Nido and histidine-tryptophan-ketoglutarate cardioplegic solutions in minimally invasive cardiac surgery

OBJECTIVE

We examined the safety and efficacy of del Nido cardioplegic solution compared with histidine-tryptophan-ketoglutarate cardioplegic solution in minimally invasive cardiac surgery.

METHODS

Patients who underwent minimally invasive cardiac surgery using del Nido or histidine-tryptophan-ketoglutarate from 2015 to 2019 were enrolled. Various clinical outcomes were compared between the groups. Postoperative laboratory findings including the levels of electrolytes, cardiac enzymes (creatine kinase-MB and troponin I), and serial blood lactate were also measured and compared. Based on 28 baseline covariates, propensity score matching was performed to reduce selection bias.

RESULTS

Among 766 patients, del Nido and histidine-tryptophan-ketoglutarate were used in 330 patients (43.1%) and 436 patients (56.9%), respectively. There were no significant intergroup differences in postoperative clinical outcomes and early adverse outcomes among 228 pairs of propensity score-matched patients. Immediate postoperative sodium levels were within the normal range in both groups without a significant difference (P = .50). However, peak creatine kinase-MB (median, 31.9 vs 37.7 ng/mL, P = .026) and troponin I (6.9 vs 9.1 ng/mL, P = .014) levels were significantly lower in the del Nido group. Linear regression analysis revealed a significant association between the peak cardiac enzyme levels and the cardiac ischemic time depending on the cardioplegia type, with lower cardiac isoenzymes for del Nido over histidine-tryptophan-ketoglutarate (P < .001) until the crossover point at the cardiac ischemic time over 100 minutes.

CONCLUSIONS

In comparison with histidine-tryptophan-ketoglutarate solution, del Nido solution seems to have acceptable safety and efficacy with good myocardial protection in minimally invasive cardiac surgery. Further studies focusing on complex surgeries requiring longer cardiac ischemic time are needed.

Use of del Nido Cardioplegia for Adult Heart Surgery: How Long Is Not Too Long?

The most apparent practical advantage of del Nido cardioplegia (DNC) is that it allows the surgeon a longer arrest period before a subsequent dose is needed, as opposed to the conventional St. Thomas' cardioplegia solution where the recommended ischemic time is ∼15-20 minutes. In this study, we explored the incidence of arrhythmia after cross-clamp removal as a surrogate for a safe myocardial ischemic time with the use of DNC in adult heart surgery. A total of 113 patients who had undergone heart valve repair and/or replacement surgery at the National University Hospital, Singapore, were investigated. This single-center retrospective study was conducted on a population where DNC had been used for myocardial protection between January 2017 and April 2019. Cardioplegia ischemic time interval groups were not significant predictors of postoperative arrhythmia, defibrillation, and intraoperative intra-aortic balloon pump usage. Crude comparison of postoperative outcomes showed no significant differences in any other postoperative variables, including mortality and total hospital stay. From the results of the present study, it appears that there is no optimal ischemic time interval for the administration of DNC within a 120-minute time period. It is likely that DNC has a redosing interval of, and may provide adequate myocardial protection, for up to 120 minutes.

DelNido cardioplegia versus St Thomas cardioplegia solution in double valve replacement: a single centre experience

INTRODUCTION

The role of cardioplegia cannot be underrated in cardiac surgery. St Thomas solution is the most widely used cardioplegic, but needs repeated dosing. Del Nido solution provides long duration of asystole with adequate protection; but has been used mainly in paediatric patients. This study was aimed to compare Del Nido cardioplegia with St Thomas cardioplegia in adult cardiac surgeries, requiring double valve replacement and compare the outcomes.

METHODOLOGY

This retrospective, observational, descriptive study was conducted over a time period spanning from January 2016 to December 2019. A total of 209 patients were included and were separated in two groups DC group (n = 114) and BC group (n = 95) on the basis of cardioplegic solution used. Del Nido solution was administered as single dose. Parameters noted were CPB time, cross clamp time, wean off bypass time, DC shocks given, inotropic support required, ventilation duration, duration of ICU and hospital stay.

RESULTS

There was significantly shorter aortic cross clamp time (72.6 ± 10.2 vs. 98.2 ± 9.2), CPB time (92.1 ± 12.3 vs.129.5 ± 11) and wean off bypass time (19.4 ± 5.9 vs. 31.3 ± 7.6) and less requirement of DC shocks (21.2% vs. 65.9%) in DC group. Inotropic requirement in immediate post-operative period was significantly less in DC group both on day of surgery (5.35 ± 1.44 vs. 7.52 ± 3.8) and 24 hours later (3.4 ± 2.12 vs. 2.18 ± 0.72). There was no significant difference in duration of ventilation, ICU and hospital stay.

CONCLUSION

Del Nido can be used safely in long duration adult cardiac surgeries and in a single dose with better intra operative and immediate post-operative outcomes as compared to St Thomas solution.

Safety and Effectiveness of Del Nido Cardioplegia in Comparison to Blood-Based St. Thomas Cardioplegia in Congenital Heart Surgeries: A Prospective Randomized Controlled Study

Background:

To compare the safety and effectiveness of del Nido cardioplegia with blood-based St Thomas Hospital (BSTH) cardioplegia in myocardial protection in congenital heart surgery.

Methods:

It is a prospective, open-labeled, randomized controlled study conducted at National Heart Institute, Kuala Lumpur from July 2018 to July 2019. All patients with simple and complex congenital heart diseases (CHD) with good left ventricular function (left ventricular ejection fraction [LVEF] >50%) were included while those with LVEF <50% were excluded. A total of 100 patients were randomized into two groups of 50 each receiving either del Nido or BSTH cardioplegia. Primary end points were the spontaneous return of activity following aortic cross-clamp release and ventricular function between two groups. Secondary end point was myocardial injury as assessed by troponin T levels.

Results:

Cardiopulmonary bypass and aortic cross-clamp time, return of spontaneous cardiac activity following the aortic cross-clamp release, the duration of mechanical ventilation, and intensive care unit stay were comparable between two groups. Statistically significant difference was seen in the amount and number of cardioplegia doses delivered ( P < .001). The hemodilution was significantly less in the del Nido complex CHD group compared to BSTH cardioplegia ( P = .001) but no difference in blood usage ( P = .36). The myocardial injury was lesser (lower troponin T release) with del Nido compared to BSTH cardioplegia ( P = .6).

Conclusion:

Our study showed that both del Nido and BSTH cardioplegia are comparable in terms of myocardial protection. However, single, less frequent, and lesser volume of del Nido cardioplegia makes it more suitable for complex repair.

Comparative Effects of Single-Dose Cardioplegic Solutions Especially in Repeated Doses During Minimally Invasive Aortic Valve Surgery

OBJECTIVE

This study aims to compare del Nido cardioplegia (DNC) and histidine-tryptophan-ketoglutarate (HTK) cardioplegic solutions in minimally invasive aortic valve replacement (mini-AVR) surgery to discuss the safety level of myocardial protection and rationale for redosing intervals.

METHODS

During the period from January 2017 to June 2019, 200 patients undergoing mini-AVR (solely or with concomitant procedures) were prospectively randomized to DNC (n = 100) andHTK (n = 100), both up to 90 minutes ischemic time. Patients with ischemic time over 90 minutes, needing a redosing, were further analyzed in 2 subgroups with DNC-R (n = 30) and HTK-R (n = 36). Sensitive biomarkers, in addition to routine biochemistry, were also documented at baseline (T1), after cessation of cardiopulmonary bypass (T2), and on the first postoperative day (T3). Transmural myocardial biopsies were sampled for staining.

RESULTS

No statistical differences could be demonstrated in DNC and HTK groups with up to 90 minutes cross-clamp times in routine biochemical measurements and basic perioperative clinical outcomes. DNC-R showed significantly more arrhythmia/AV block incidence resulting in more extended intensive care unit (ICU) stay. Interleukin-6 and syndecan-1 in DNC and DNC-R groups were substantially higher at T2. Aquaporin-4 levels were significantly lower in the DNC-R group, demonstrating unsatisfactory response of cells to an excessive volume at T2.

CONCLUSIONS

DNC and HTK provided acceptable myocardial protection as single-dose applications. DNC-R had significantly unbalanced levels of biomarkers, and more arrhythmia/AV block incidence resulting in more extended ICU stay. For patients who may need redosing HTK may be preferable to DNC.

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.

Effect of single-dose crystalloid cardioplegic agent compared to bloody cardioplegic agent in cardiac surgery in children with Tetralogy of Fallot

BACKGROUND

Cardioplegia is one of the main post-operative cardiac protective factors widely used in recent decades in the form of crystalloid (St. Thomas) and bloody solutions [del Nido (DN)]. The purpose of this study was to compare the effect of a crystalloid cardioplegic agent (St. Thomas) with that of a bloody cardioplegic agent (DN) in pediatric cardiac surgery among children with Tetralogy of Fallot (TOF).

METHODS

This study was performed on 60 children with TOF, who were candidates for heart repair surgery. The participants were randomly divided into two groups of crystalloid cardioplegic agent and bloody cardioplegic agent. Operative outcomes such as required time for onset of heart arrest, duration of returning to normal heart rhythm, and cardiopulmonary bypass (CPB) time, and operative complications were compared between the two groups.

RESULTS

The duration of returning to normal heart rhythm (50.43 ± 10.93 seconds vs. 43.03 ± 16.35 seconds; P = 0.044) and duration of inotropy (80.40 ± 27.14 hours vs. 63.20 ± 26.91 hours; P = 0.017) were significantly higher in the DN group compared to the St. Thomas group. However, there were no significant differences between the two groups in terms of heart arrest time, cross-clamp time, CPB time, supplementary lasix time, duration of intubation, and intensive care unit (ICU) and hospital length of stay (LOS) (P > 0.050).

CONCLUSION

The use of St. Thomas cardioplegic solution was more effective in reducing the duration of returning to normal heart rhythm and inotropy compared with DN cardioplegic agent, and a single dose of these two cardioplegic agents can keep the mean cardiac arrest duration within the range of 50-70 minutes. It seems that the use of St. Thomas cardioplegic solution can be suggested in pediatric heart surgery.

Comparison of outcomes of the use of Del Nido and St. Thomas cardioplegia in adult and paediatric cardiac surgery: a systematic review and meta-analysis

Background:

In recent years, the use of del Nido cardioplegia, initially intended for paediatric cardiac surgery, has been extended to adult cardiac surgery in many institutions. Our aim was thus to compare the outcomes of the use of del Nido cardioplegia with that of conventional cardioplegia and discuss its role in both adult and paediatric cardiac surgery.

Method:

A systematic literature search was conducted in August 2019 on Medline (via PubMed), Embase and Cochrane electronic databases according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Any retrospective studies and randomised controlled trials that reported findings comparing the outcomes of the use of del Nido cardioplegia with that of St. Thomas cardioplegia were included.

Results:

We observed shorter aortic cross-clamp time (mean difference: −15.18, confidence interval: −27.21 to −3.15, p = 0.01) and cardiopulmonary bypass time (mean difference: −13.52, confidence interval: −20.64 to −6.39, p = 0.0002) associated with the use of del Nido cardioplegia in adult cardiac surgery as compared to St. Thomas cardioplegia. Defibrillation rates were significantly lower in patients who had been given del Nido cardioplegia, in both adult (relative risk: 0.28, confidence interval: 0.12 to 0.64, p = 0.003) and paediatric patients (relative risk: 0.25, confidence interval: 0.08 to 0.79, p = 0.02).

Conclusion:

Del Nido cardioplegia may be a viable alternative to the use of St. Thomas cardioplegia in both adult and paediatric patients, providing similar postoperative outcomes while also affording the additional advantage of shorter aortic cross-clamp time and cardiopulmonary bypass time (in adult cardiac surgery) and decreased rates of defibrillation (in both adult and paediatric cardiac surgery).

Modified Del Nido Cardioplegia and Its Evaluation in a Piglet Model

Del Nido cardioplegia (DN) is not available worldwide as the required solution is made from a commercial base (PlasmaLyte) that is not approved in all countries. We report our own modified DN solution and confirm its safety and effectiveness. Fourteen piglets were subjected to 90 minutes of global ischemia on cardiopulmonary bypass induced by original DN (n = 7) or NS (normal saline)-based DN (n = 7). Our DN solution begins with a base of NS (800 mL) and distilled water (200 mL), to which are added 15 mL KCl (2 mEq/mL), 17 mL NaHCO₃ (1 mEq/mL), 10 mL MgSO₄ (0.2 g/mL), 13 mL lidocaine 1%, and 13 mL mannitol 25%. LV function recovery was assessed in end-systolic elastance (EES) as systolic function and end-diastolic pressure-volume relationship (EDPVR) as diastolic function using a conductance catheter. Creatine kinase-MB (CK-MB) and mitochondrial score were also measured. Left ventricular (LV) contractility after ischemia (%EES ± SD) was not significantly different between the group induced by original DN (89.3 ± 20.6%) and the group induced by NS-based DN (99.3 ± 18.4%). LV compliance (%EDPVR ± SD) was likewise not significantly different between these groups (102.7 ± 28.2% vs 94.4 ± 22.8%, PL vs NS, respectively). CK-MB was equivalent between the groups. Mitochondrial scores were not significantly different between the groups, and this difference did not cause severe damage. NS-based DN preserves LV function recovery after prolonged global ischemia as effectively and as safely as original DN does. NS-based modified DN can be substituted for original DN.

Investigating the physiology of normothermic ex vivo heart perfusion in an isolated slaughterhouse porcine model used for device testing and training

Background

The PhysioHeart™ is a mature acute platform, based isolated slaughterhouse hearts and able to validate cardiac devices and techniques in working mode. Despite perfusion, myocardial edema and time-dependent function degradation are reported. Therefore, monitoring several variables is necessary to identify which of these should be controlled to preserve the heart function. This study presents biochemical, electrophysiological and hemodynamic changes in the PhysioHeart™ to understand the pitfalls of ex vivo slaughterhouse heart hemoperfusion.

Methods

Seven porcine hearts were harvested, arrested and revived using the PhysioHeart™. Cardiac output, SaO2, glucose and pH were maintained at physiological levels. Blood analyses were performed hourly and unipolar epicardial electrograms (UEG), pressures and flows were recorded to assess the physiological performance.

Results

Normal cardiac performance was attained in terms of mean cardiac output (5.1 ± 1.7 l/min) and pressures but deteriorated over time. Across the experiments, homeostasis was maintained for 171.4 ± 54 min, osmolarity and blood electrolytes increased significantly between 10 and 80%, heart weight increased by 144 ± 41 g, free fatty acids (− 60%), glucose and lactate diminished, ammonia increased by 273 ± 76% and myocardial necrosis and UEG alterations appeared and aggravated. Progressively deteriorating electrophysiological and hemodynamic functions can be explained by reperfusion injury, waste product intoxication (i.e. hyperammonemia), lack of essential nutrients, ion imbalances and cardiac necrosis as a consequence of hepatological and nephrological plasma clearance absence.

Conclusions

The PhysioHeart™ is an acute model, suitable for cardiac device and therapy assessment, which can precede conventional animal studies. However, observations indicate that ex vivo slaughterhouse hearts resemble cardiac physiology of deteriorating hearts in a multi-organ failure situation and signalize the need for plasma clearance during perfusion to attenuate time-dependent function degradation. The presented study therefore provides an in-dept understanding of the sources and reasons causing the cardiac function loss, as a first step for future effort to prolong cardiac perfusion in the PhysioHeart™. These findings could be also of potential interest for other cardiac platforms.

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.

Del Nido cardioplegia - what is the current evidence?

Del Nido cardioplegia is believed to be both clinically and economically efficient. The interest in this myocardial protection method has been continuously growing. However, the evidence is not clear. The article summarizes recent reports regarding del Nido cardioplegia.

Oral thyroxin supplementation in infants undergoing cardiac surgery: A double-blind placebo-controlled randomized clinical trial

BACKGROUND

Decreases in serum total thyroxin and total triiodothyronine occurs after cardiopulmonary bypass, and is reflected as poor immediate outcome. We studied effects of oral thyroxin supplementation in infants who underwent open-heart surgery.

METHODS

In this prospective study, 100 patients were randomized into 2 groups: 50 in the thyroxin group (TH) and 50 in the placebo group (PL). Patients in the TH group received oral thyroxin (5 μg/kg) 12 hours before surgery and once daily for the remainder of their intensive care unit (ICU) stay. Data on intraoperative and postoperative variables were recorded. Cardiac index (CI) was measured. Perioperative serum thyroid hormone levels and serum interleukin-6 and tumor necrosis factor-α were measured. Secondary analysis was performed by dividing patients into simple and complex subcategories.

RESULTS

Results of the primary analysis indicated a higher CI in the TH compared with the PL. In the complex category, the mean duration of mechanical ventilation was 3.85 ± 0.93 and 4.66 ± 1.55 days in the TH and PL, respectively (P = .001). Mean ICU stay was 6.79 ± 2.26 and 8.33 ± 3.09 days (P = .03), and mean hospital stay was 15.70 ± 4.77 and 18.90 ± 4.48 days (P = .01) in the TH and PL, respectively. There were no significant differences between the TH and the PL in the simple category. CI was higher in the TH at all time points (P = .004). The average therapeutic intervention scoring system scores for the first 2 days were higher in the PL in the complex category.

CONCLUSIONS

Oral thyroxin supplementation improves the CI and reduces the inotropic requirement. In addition, it reduces the duration of mechanical ventilation, ICU and hospital stay, and therapeutic intervention scoring system in infants after surgery for complex congenital heart defects.

Recent innovations in perfusion and cardiopulmonary bypass for neonatal and infant cardiac surgery

The development and refinement of cardiopulmonary bypass (CPB) has made the repair of complex congenital heart defects possible in neonates and infants. In the past, the primary goal for these procedures was patient survival. Now that substantial survival rates have been achieved for even the most complex of repairs in these patients, focus has been given to the reduction of morbidity. Although a necessity for these complex neonatal and infant heart defect repairs, CPB can also be an important source of perioperative complications. Recent innovations have been developed to mitigate these risks and is the topic of this review. Specifically, we will discuss improvements in minimizing blood transfusions, CPB circuit design, monitoring, perfusion techniques, temperature management, and myocardial protection, and then conclude with a brief discussion of how further systematic improvements can be made in these areas.