Postoperative Extracorporeal Membrane Oxygenation Research Articles

Comparison of HTK-Custodiol and St-Thomas solution as cardiac preservation solutions on early and midterm outcomes following heart transplantation.

The choice of the cardiac preservation solution for myocardial protection at time of heart procurement remains controversial and uncertainties persist regarding its effect on the early and midterm heart transplantation (HTx) outcomes. We retrospectively compared our adult HTx performed with 2 different solutions, in terms of hospital mortality, mid-term survival, inotropic score, primary graft dysfunction and rejection score. From January 2009 to December 2020, 154 consecutive HTx of adult patients, followed up in pre- and post-transplantation by 2 different tertiary centres, were performed at the University Hospital of Lausanne, Switzerland. From 2009 to 2015, the cardiac preservation solution used was exclusively St-Thomas, whereafter an institutional decision was made to use HTK-Custodiol only. Patients were classified in 2 groups accordingly. There were 75 patients in the St-Thomas group and 79 patients in the HTK-Custodiol group. The 2 groups were comparable in terms of preoperative and intraoperative characteristics. Postoperatively, compared to the St-Thomas group, the Custodiol group patients showed significantly lower inotropic scores [median (interquartile range): 35.7 (17.5-60.2) vs 71.8 (31.8-127), P < 0.001], rejection scores [0.08 (0.0-0.25) vs 0.14 (0.05-0.5), P = 0.036] and 30-day mortality rate (2.5% vs 14.7%, P = 0.007) even after adjusting for potential confounders. Microscopic analysis of the endomyocardial biopsies also showed less specific histological features of subendothelial ischaemia (3.8% vs 17.3%, P = 0.006). There was no difference in primary graft dysfunction requiring postoperative extracorporeal membrane oxygenation. The use of HTK-Custodiol solution significantly improved midterm survival (Custodiol versus St-Thomas: hazard ratio = 0.20, 95% confidence interval: 0.069-0.60, P = 0.004). This retrospective study comparing St-Thomas solution and HTK-Custodiol as myocardial protection during heart procurement showed that Custodiol improves outcomes after HTx, including postoperative inotropic score, rejection score, 30-day mortality and midterm survival.

The Perioperative Period of Heart Transplantation Is Affected by Thyroid Hormone Status.

Background: Orthotopic heart transplantation (HTx) is a long-term surgical therapeutic approach for patients with end-stage heart failure. The objective of the present study was to uncover associations between altered thyroid hormone (TH) status and adverse outcomes after HTx. Methods: In this prospective, single-center cohort study, 283 patients underwent HTx between 2013 and 2020 at the Heart and Vascular Center of Semmelweis University in Hungary. We measured serum free triiodothyronine (fT3), free thyroxine (fT4), and thyrotropin (TSH) pre- and postoperatively. TaqMan qPCR was used to measure type 2 deiodinase and type 3 deiodinase mRNA (Dio2 and Dio3, respectively) levels from the diseased heart bioptates. To assess the local TH action of the heart, mRNA levels of Hcn2 and Myh7 were measured in a subgroup of patients receiving extracorporeal membrane oxygenation (ECMO) postoperatively. Groups were compared using nonparametric tests. Cox regression analysis and logistic regression test were used to investigate the outcomes. The connection between serum TH parameters and cardiac gene expressions was assessed using linear regression. Results: Serum TSH (p = 0.009), fT3 (p < 0.001), and fT4 (p < 0.001) levels were lower after HTx than preoperatively. Levothyroxine (LT4) administered to donors was associated with better survival after 30 days (p = 0.049). LT4 replacement given to recipients after HTx was associated with better survival after 30 days (p = 0.018), 1 year (p = 0.002), and 2 years (p = 0.001). Dio3 mRNA level was significantly increased in patients who were treated with ECMO (p = 0.026), left ventricular assist device (LVAD) (p = 0.008), and biventricular assist device (BiVAD) (p = 0.013) preoperatively, and ECMO (p = 0.042) postoperatively, compared with those who did not require any type of mechanical circulatory support (MCS). We found no significant difference in the expression of the Hcn2 and Myh7 marker genes between patients on postoperative ECMO and those without MCS, and neither did they correlate with serum hormone levels (p = 0.519 and p = 0.056, respectively). Conclusions: We conclude that TH status plays an important role in HTx patients, and monitoring of TH status in the perioperative period may contribute to improved treatment outcomes. Our findings require independent confirmation in a randomized controlled clinical trial.

Early outcomes of moderate-to-high-risk pediatric congenital cardiac surgery and predictors of extracorporeal circulatory life support requirement.

Cardiopulmonary failure refractory to medical management after moderate-to-high-risk congenital cardiac surgery may necessitate mechanical support with veno-arterial extracorporeal membrane oxygenation (ECMO). On the extreme, ECMO can also be initiated in the setting of cardiac arrest (extracorporeal cardiopulmonary resuscitation, ECPR) unresponsive to conventional resuscitative measures. This was a single-center retrospective cohort study of patients (n = 510) aged <3 years old who underwent cardiac surgery with cardiopulmonary bypass with a RACHS-1 score ≥3 between 2011 and 2014. Perioperative factors were reviewed to identify predictors of ECMO initiation and mortality in the operating room (OR) and the intensive care unit (ICU). A total of 510 patients with a mean surgical age of 10.0 ± 13.4 months were included. Among them, 21 (4%) patients received postoperative ECMO-12 were initiated in the OR and 9 in the ICU. ECMO cannulation was associated with cardiopulmonary bypass duration, aortopulmonary shunt, residual severe mitral regurgitation, vaso-inotropic score, and postprocedural lactate (p < 0.001). Of the 32 (6%) total deaths, 7 (22%) were ECMO patients-4 were elective OR cannulations and 3 were ICU ECPR. Prematurity [hazard ratio (HR): 2.61, p < 0.01), Norwood or Damus-Kaye-Stansel procedure (HR: 4.29, p < 0.001), postoperative left ventricular dysfunction (HR: 5.10, p = 0.01), residual severe tricuspid regurgitation (HR: 6.06, p < 0.001), and postoperative ECMO (ECPR: HR: 15.42, p < 0.001 vs. elective: HR: 5.26, p = 0.01) were associated with mortality. The two patients who were electively cannulated in the ICU survived. Although uncommon, postoperative ECMO in children after congenital cardiac surgery is associated with high mortality, especially in cases of ECPR. Patients with long cardiopulmonary bypass time, residual cardiac lesions, or increased vaso-inotropic requirement are at higher risk of receiving ECMO. Pre-emptive or early ECMO initiation before deterioration into cardiac arrest may improve survival.

Extended ischemic time (>15 hours) using controlled hypothermic storage in lung transplantation: A multicenter experience

Static ice storage has long been the standard-of-care for lung preservation, although freezing injury limits ischemic time (IT). Controlled hypothermic storage (CHS) at elevated temperature could safely extend IT. This retrospective analysis assesses feasibility and safety of CHS with IT>15h. Three lung transplant (LuTx) centers (April-October 2023) included demographics, storage details, IT and short-term outcome from 13 LuTx recipients (8 male, 59 years old). Donor lungs were preserved in a portable CHS-device at 7(5-9.3)°C. Indication was overnight bridging and/or long-distance transport. IT of second-implanted lung was 17.3(15.1-22)h. LuTx were successful, 4/13 exhibited primary graft dysfunction grade 3 within 72h and 0/13 at 72h. Post-LuTx mechanical ventilation was 29(7-442)h. Intensive care unit stay was 9(5-28) and hospital stay 30(16-90) days. Four patients needed post-operative extracorporeal membrane oxygenation (ECMO). One patient died (day seven) following malpositioning of an ECMO cannula. This multi-center experience demonstrates the possibility of safely extending IT>15h by CHS.

Role of extracorporeal life support for traumatic hemopericardium: A single level I trauma center review

BackgroundTraumatic hemopericardium may lead to cardiac tamponade, arrhythmia, arrest, or death and requires emergency surgery. We reviewed cases of traumatic hemopericardium in our center and the role of extracorporeal life support in these cases. MethodsFrom November 2011 to January 2022, 28 patients with significant hemopericardium and suspected cardiac injury were enrolled. In our center, surgery is the primary treatment of choice; however, if the patient is in an unstable condition, extracorporeal life support is administered in the emergency room prior to surgery. ResultsPreoperative extracorporeal life support was applied to 10 patients (36 %). Two patients (20 %) were converted from extracorporeal life support to cardiopulmonary bypass during operation. After surgery, 2 patients (20 %) needed postoperative extracorporeal membrane oxygenation support. Overall, 21 patients (75 %) survived; of these, 6 (29 %) received extracorporeal life support. Meanwhile, 7 patients (25 %) died; of these, 4 patients (57 %) received extracorporeal life support. ConclusionResuscitation method is the most crucial survival strategy in patients with severe chest trauma. Extracorporeal life support in cases of traumatic hemopericardium may be beneficial and efficient in stabilizing patients prior to surgery.

Lung recovery utilizing thoracoabdominal normothermic regional perfusion during donation after circulatory death: The Colorado experience

ObjectiveDonation after circulatory death (DCD) procurement and transplantation after thoracoabdominal normothermic regional perfusion (TA-NRP) remains a novel technique to improve cardiac and hepatic allograft preservation but may be complicated by lung allograft pulmonary edema. We present a single-center series on early implementation of a lung-protective protocol with strategies to mitigate posttransplant pulmonary edema in DCD lung allografts after TA-NRP procurement. MethodsData from all lung transplantations performed using a TA-NRP procurement strategy from October 2022 to April 2023 are presented. Donor management consisted of key factors to reduce lung allograft pulmonary edema: aggressive predonation and early posttransplant diuresis, complete venous drainage at TA-NRP initiation, and early pulmonary artery venting upon initiation of systemic perfusion. Donor and recipient characteristics, procurement characteristics such as TA-NRP intervals, and 30-day postoperative outcomes were assessed. ResultsDuring the study period, 8 lung transplants were performed utilizing TA-NRP procurement from DCD donors. Donor ages ranged from 16 to 39 years and extubation time to declaration of death ranged from 10 to 90 minutes. Time from declaration to TA-NRP initiation was 7 to 17 minutes with TA-NRP perfusion times of 49 to 111 minutes. Median left and right allograft warm ischemia times were 55.5 minutes (interquartile range, 46.5-67.5 minutes) and 41.0 minutes (interquartile range, 39.0-53.0 minutes, respectively, with 2 recipients supported with cardiopulmonary bypass or venoarterial extracorporeal membrane oxygenation during implantation. No postoperative extracorporeal membrane oxygenation was required. There were no pulmonary-related deaths; however, 1 patient died from complications of severe necrotizing pancreatitis with a normal functioning allograft. All patients were extubated within 24 hours. Index intensive care unit length of stay ranged from 3 to 11 days with a hospital length of stay of 13 to 37 days. ConclusionsDespite concern regarding quality of DCD lung allografts recovered using the TA-NRP technique, we report initial success using this procurement method. Implementation of strategies to mitigate pulmonary edema can result in acceptable outcomes following lung transplantation. Demonstration of short- and long-term safety and efficacy of this technique will become increasingly important as the use of TA-NRP for thoracic and abdominal allografts in DCD donors expands.

National In-Hospital Outcomes of Mechanical Mitral Valve Replacement in the Pediatric Population.

Background: National data about the outcomes of children undergoing mechanical mitral valve replacement (m-MVR) are scarce. Methods: A retrospective review of hospitalizations from the Kids' Inpatient Database was performed for patients ≤18 years of age in the United States. A total of 500 patients underwent m-MVR in 2009, 2012, 2016, and 2019. Patients with single ventricle physiology were excluded (n = 13). These patients were categorized into three groups according to age: neonates (<1 month, n = 20), infants (1-12 months, n = 76 patients), and children (1-18 years, n = 404). Outcomes were compared between the three groups. Results: The proportion of m-MVR involving children undergoing MV procedures (repair and replacement) has increased from 17.3% in 2009 to 30.8% in 2019 (Ptrend < .01). History of cardiac surgery was present in 256 patients (51.2%). Concomitant procedures were performed in 119 patients (23.8%). Intra- or postoperative extracorporeal membrane oxygenation was required in 19 patients (3.8%). The overall in-hospital mortality was 4.8% and was significantly higher in neonates and infants compared with older children (10% vs 11.8% vs 3.2%, P = .003). The length of hospital stay was longer in the neonatal group (median, 57 days, interquartile range, [24.8-90] vs 29.5 days [15.5-61] vs 10 days [7-18], P < .01). Nonhome discharges were more common in neonates and infants (40% vs 36.8% vs 13.1%, P < .01). Conclusion: Mechanical mitral valve replacement is increasingly performed over time with acceptable in-hospital morbidity and mortality, especially in older children and adolescents. Neonates and infants are associated with worse hospital survival, prolonged hospitalization, and significant rates of nonhome discharges.

Disparity Analysis for Cardiac Surgical Outcomes: The Citizenship Factor.

(1) Background: Disparity in clinical care on the basis of gender, socioeconomic status, ethnic and racial variation is an established phenomenon. The focus on health disparities was led on by the report of the Secretary's Task Force on Black & Minority Health, which emphasized that the burden of death and illness was in excess among black people and other minorities. In Saudi Arabia, cardiac health care is being provided to a heterogeneous group of patients during pilgrimage time. This mixed population comprises different socio-economic backgrounds, demographics, ethnicities and languages. This study was carried out to assess for any disparities in cardiac surgical outcomes after isolated CABG surgery between Saudi citizens and non-Saudi patients. (2) Methods: The data of 2178 patients who underwent isolated coronary artery bypass surgery at King Abdullah Medical City from December 2014 to July 2020 were extracted. Patient demographics, clinical features, comorbidities, diagnoses, surgical procedures, complications, length of hospital stay and mortality were included in the data. The primary outcome was mortality after coronary artery bypass grafting surgery. (3) Results: A total of 2178 isolated CABG procedures were conducted during the study period with almost 57.5% of patients being Saudi citizens in comparison with 42.5% of non-Saudi citizens. The male gender represented the majority of the population, with a total of 1584 patients, representing 72.7% of the total study population. The rate of mortality had no statistical significance with the mortality rate of 5% vs. 5.3% (p < 0.786). The postoperative morbidities were comparable for all the parameters except for postoperative extracorporeal membrane oxygenation (ECMO). (4) Conclusions: In the present study, the chances of survival and postoperative outcomes are not associated with nationality per se, but with underlying comorbidities.

Heart transplantation as a rescue strategy for patients with refractory electrical storm.

Heart transplantation (HT) can be proposed as a therapeutic strategy for patients with severe refractory electrical storm (ES). Data in the literature are scarce and based on case reports. We aimed at determining the characteristics and survival of patients transplanted for refractory ES. Patients registered on HT waiting list during the following days after ES and eventually transplanted, from 2010 to 2021, were retrospectively included in 11 French centers. The primary endpoint was in-hospital mortality. 45 patients were included (82% men; 55.0 (47.8-59.3) years old; 42.2% and 26.7% non-ischemic dilated or ischemic cardiomyopathies, respectively). Among them, 42 (93.3%) received amiodarone, 29 (64.4%) betablockers; 19 (42.2%) required deep sedation, 22 (48.9%) mechanical circulatory support, and 9 (20.0%) had radiofrequency catheter ablation. Twenty-two patients (62%) were in cardiogenic shock. Inscription on wait list and transplantation occurred 3.0 (1.0-5.0) days and 9.0 (4.0-14.0) days after ES onset, respectively. After transplantation, 20 patients (44.4%) needed immediate hemodynamic support by extracorporeal membrane oxygenation (ECMO). In-hospital mortality rate was 28.9%. Predictors of in-hospital mortality were serum creatinine/urea levels, need for immediate post-operative ECMO support, post-operative complications, and surgical re-interventions. One-year survival was 68.9%. ES is a rare indication of HT but may be lifesaving in those patients presenting intractable arrhythmias despite usual care. Most patients can be safely discharged from hospital, although post-operative mortality remains substantial in this context of emergency transplantation. Larger studies are warranted to precisely determine those patients at higher risk of in-hospital mortality.

The effect of allograft ischemic time on outcomes following bilateral, single, and reoperative lung transplantation

ObjectiveTo determine whether allograft ischemic times affect outcomes following bilateral, single, and redo lung transplantation. MethodsA nationwide cohort of lung transplant recipients from 2005 through 2020 was examined using the Organ Procurement and Transplantation Network registry. The effects of standard (<6 hours) and extended (≥6 hours) ischemic times on outcomes following primary bilateral (n = 19,624), primary single (n = 688), redo bilateral (n = 8461), and redo single (n = 449) lung transplantation were analyzed. A priori subgroup analysis was performed in the primary and redo bilateral-lung transplant cohorts by further stratifying the extended ischemic time group into mild (≥6 and <8 hours), moderate (≥8 and <10 hours), and long (≥10 hours) subgroups. Primary outcomes included 30-day mortality, 1-year mortality, intubation at 72 hours' posttransplant, extracorporeal membrane oxygenation (ECMO) support at 72 hours' posttransplant, and a composite variable of intubation or ECMO at 72 hours' posttransplant. Secondary outcomes included acute rejection, postoperative dialysis, and hospital length of stay. ResultsRecipients of allografts with ischemic times ≥6 hours experienced increased 30-day and 1-year mortality following primary bilateral-lung transplantation, but increased mortality was not observed following primary single, redo bilateral, or redo single-lung transplants. Extended ischemic times correlated with prolonged intubation or increased postoperative ECMO support in the primary bilateral, primary single, and redo bilateral-lung transplant cohorts but did not affect these outcomes following redo single-lung transplantation. ConclusionsSince prolonged allograft ischemia correlates with worse transplant outcomes, the decision to use donor lungs with extended ischemic times must consider the specific benefits and risks associated with individual recipient factors and institutional expertise.

Tricuspid Regurgitation After Heart Transplantation: The Cause or the Result of Graft Dysfunction?

Tricuspid regurgitation (TR) is common following heart transplantation and has been shown to adversely influence patient outcomes. The aim of this study was to identify causes of progression to moderate-severe TR in the first 2 y after transplantation. This was a retrospective, single-center study of all patients who underwent heart transplantation over a 6-y period. Transthoracic echocardiogram (TTE) was performed at month 0, between 6 and 12 mo, and 1-2 y postoperatively to determine the presence and severity of TR. A total of 163 patients were included, of whom 142 underwent TTE before first endomyocardial biopsy. At month 0, 127 (78%) patients had nil-mild TR before first biopsy, whereas 36 (22%) had moderate-severe TR. In patients with nil-mild TR, 9 (7%) progressed to moderate-severe TR by 6 mo and 1 underwent tricuspid valve (TV) surgery. Of patients with moderate-severe TR before first biopsy, by 2 y, 3 had undergone TV surgery. The use of postoperative extracorporeal membrane oxygenation (ECMO) in the latter group was significant (78%; P < 0.05) as was rejection profile ( P = 0.02). Patients with late progressive moderate-severe TR had a significantly higher 2-y mortality than those who had moderate-severe TR immediately. Overall, our study has shown that in the 2 main groups of interest (early moderate-severe TR and progression from nil-mild to moderate-severe TR), TR is more likely to be the result of significant underling graft dysfunction rather than the cause of it.

The importance of timing in postcardiotomy venoarterial extracorporeal membrane oxygenation: A descriptive multicenter observational study

ObjectivesPostcardiotomy extracorporeal membrane oxygenation (ECMO) can be initiated intraoperatively or postoperatively based on indications, settings, patient profile, and conditions. The topic of implantation timing only recently gained attention from the clinical community. We compare patient characteristics as well as in-hospital and long-term survival between intraoperative and postoperative ECMO. MethodsThe retrospective, multicenter, observational Postcardiotomy Extracorporeal Life Support (PELS-1) study includes adults who required ECMO due to postcardiotomy shock between 2000 and 2020. We compared patients who received ECMO in the operating theater (intraoperative) with those in the intensive care unit (postoperative) on in-hospital and postdischarge outcomes. ResultsWe studied 2003 patients (women: 41.1%; median age: 65 years; interquartile range [IQR], 55.0-72.0). Intraoperative ECMO patients (n = 1287) compared with postoperative ECMO patients (n = 716) had worse preoperative risk profiles. Cardiogenic shock (45.3%), right ventricular failure (15.9%), and cardiac arrest (14.3%) were the main indications for postoperative ECMO initiation, with cannulation occurring after (median) 1 day (IQR, 1-3 days). Compared with intraoperative application, patients who received postoperative ECMO showed more complications, cardiac reoperations (intraoperative: 19.7%; postoperative: 24.8%, P = .011), percutaneous coronary interventions (intraoperative: 1.8%; postoperative: 3.6%, P = .026), and had greater in-hospital mortality (intraoperative: 57.5%; postoperative: 64.5%, P = .002). Among hospital survivors, ECMO duration was shorter after intraoperative ECMO (median, 104; IQR, 67.8-164.2 hours) compared with postoperative ECMO (median, 139.7; IQR, 95.8-192 hours, P < .001), whereas postdischarge long-term survival was similar between the 2 groups (P = .86). ConclusionsIntraoperative and postoperative ECMO implantations are associated with different patient characteristics and outcomes, with greater complications and in-hospital mortality after postoperative ECMO. Strategies to identify the optimal location and timing of postcardiotomy ECMO in relation to specific patient characteristics are warranted to optimize in-hospital outcomes.

Capillary Refill Time and Serum Lactate as Predictors of Mortality and Postoperative Extracorporeal Membrane Oxygenation Requirement in Congenital Heart Surgery.

Multiple tissue perfusion markers are described to guide therapy in critically ill pediatric patients undergoing congenital heart surgery. Given the advantages of capillary refill time, our goal is to determine its predictive capacity for mortality and postoperative extracorporeal oxygenation requirements in congenital heart surgery and compare it to serum lactate. We conducted a prospective cohort observational study in a single high-complexity university hospital. Serum lactate and capillary refill time were measured at five predetermined time points: preoperative, immediate postoperative, 6, 12, and 24 h after the surgery. Prolonged immediate postoperative, 6 h, and 12 h capillary refill time measurements turned out to be independent risk factors for both outcomes. The capillary refill time area under the curve ranged between 0.70 and 0.80, while the serum lactate resulted between 0.79 and 0.92 for both outcomes. Both tissue perfusion markers resulted in mortality and extracorporeal oxygenation requirement predictors. Given the advantages of capillary refill time over serum lactate, a monitoring strategy including these two perfusion markers should be considered for congenital heart surgeries.

Machine Learning–Based Prognostic Model for Patients After Lung Transplantation

Although numerous prognostic factors have been found for patients after lung transplantation (LTx) over the years, an accurate prognostic tool for LTx recipients remains unavailable. To develop and validate a prognostic model for predicting overall survival in patients after LTx using random survival forests (RSF), a machine learning algorithm. This retrospective prognostic study included patients who underwent LTx between January 2017 and December 2020. The LTx recipients were randomly assigned to training and test sets in accordance with a ratio of 7:3. Feature selection was performed using variable importance with bootstrapping resampling. The prognostic model was fitted using the RSF algorithm, and a Cox regression model was set as a benchmark. The integrated area under the curve (iAUC) and integrated Brier score (iBS) were applied to assess model performance in the test set. Data were analyzed from January 2017 to December 2019. Overall survival in patients after LTx. A total of 504 patients were eligible for this study, consisting of 353 patients in the training set (mean [SD] age, 55.03 [12.78] years; 235 [66.6%] male patients) and 151 patients in the test set (mean [SD] age, 56.79 [10.95] years; 99 [65.6%] male patients). According to the variable importance of each factor, 16 were selected for the final RSF model, and postoperative extracorporeal membrane oxygenation time was identified as the most valuable factor. The RSF model had excellent performance with an iAUC of 0.879 (95% CI, 0.832-0.921) and an iBS of 0.130 (95% CI, 0.106-0.154). The Cox regression model fitted by the same modeling factors to the RSF model was significantly inferior to the RSF model with an iAUC of 0.658 (95% CI, 0.572-0.747; P < .001) and an iBS of 0.205 (95% CI, 0.176-0.233; P < .001). According to the RSF model predictions, the patients after LTx were stratified into 2 prognostic groups displaying significant difference, with mean overall survival of 52.91 months (95% CI, 48.51-57.32) and 14.83 months (95% CI, 9.44-20.22; log-rank P < .001), respectively. In this prognostic study, the findings first demonstrated that RSF could provide more accurate overall survival prediction and remarkable prognostic stratification than the Cox regression model for patients after LTx.

Extension of Cold Static Donor Lung Preservation at 10°C

BackgroundLung transplantation is performed on a 24/7 schedule to minimize organ ischemic time. Recent preclinical studies demonstrated superior graft preservation at 10°C compared with storage in an ice cooler (gold standard).MethodsIn this prospective, multicenter, nonrandomized clinical trial, we studied transplants from donors with overnight cross-clamp times (6:00 p.m. to 4:00 a.m.) that had an earliest allowed starting time of 6:00 a.m. Lungs meeting criteria for transplantation were retrieved, transported, and immediately transferred to a 10°C temperature-controlled incubator until implantation; 70 patients and 140 matched controls were included in this study.ResultsTotal preservation times for lungs in the study group were 12 hours, 28 minutes (interquartile range, 10 hours, 14 minutes to 14 hours, 12 minutes) and 14 hours, 9 minutes (interquartile range, 12 hours, 3 minutes to 15 hours, 45 minutes) for the first and second lung implanted, respectively. Primary graft dysfunction grade 3 at 72 hours (primary outcome) was 5.7% in the study group versus 9.3% in matched controls (difference, −3.6; 95% confidence interval [CI], −10.5 to 5.3). No meaningful differences were observed in the need for postoperative extracorporeal membrane oxygenation (5.7 vs. 9.3%), median intensive care unit stay (5 vs. 5 days), or median hospital stay (25 vs. 30 days) between the two groups. One-year Kaplan–Meier survival was similar between the two groups (94 vs. 87%; hazard ratio, 0.65; 95% CI, 0.26 to 1.6).ConclusionsExtension of cold static preservation times at 10°C appears to be safe and has the potential to improve transplantation logistics and performance. (Funded by the UHN Foundation; Clinicaltrials.gov number, NCT04616365).

Delayed Sternal Closure Using a Vacuum-Assisted Closure System in Adult Cardiac Surgery.

Delayed sternal closure (DSC) is a useful option for patients with intractable bleeding and hemodynamic instability due to prolonged cardiopulmonary bypass and a preoperative bleeding tendency. Vacuum-assisted closure (VAC) has been widely used for sternal wound problems, but only rarely for DSC, and its efficacy for mediastinal drainage immediately after cardiac surgery has not been well established. Therefore, we evaluated the usefulness of DSC using VAC in adult cardiac surgery. We analyzed 33 patients who underwent DSC using VAC from January 2017 to July 2022. After packing sterile gauze around the heart surface and great vessels, VAC was applied directly without sternal self-retaining retractors and mediastinal drain tubes. Twenty-one patients (63.6%) underwent emergency surgery for conditions including type A acute aortic dissection (n=13), and 8 patients (24.2%) received postoperative extracorporeal membrane oxygenation support. Intractable bleeding (n=25) was the most common reason for an open sternum. The median duration of open sternum was 2 days (interquartile range [25th-75th pertentiles], 2-3.25 days) and 9 patients underwent VAC application more than once. The overall in-hospital mortality rate was 27.3%. Superficial wound problems occurred in 10 patients (30.3%), and there were no deep sternal wound infections. For patients with an open sternum, VAC alone, which is effective for mediastinal drainage and cardiac decompression, had an acceptable superficial wound infection rate and no deep sternal wound infections. In adult cardiac surgery, DSC using VAC may be useful in patients with intractable bleeding or unstable hemodynamics with myocardial edema.

(405) Predictors and Outcomes of Post-Operative Extracorporeal Membrane Oxygenation at 72 Hours Following Lung Transplantation

(405) Predictors and Outcomes of Post-Operative Extracorporeal Membrane Oxygenation at 72 Hours Following Lung Transplantation

Mildly Elevated Pulmonary Artery Systolic Pressure is Associated with Extracorporeal Membrane Oxygenation Support after Heart Transplantation

Background. Pulmonary hypertension is a well-known risk factor for hemodynamic instability after heart transplantation. However, it remains unclear whether a mild elevation of pulmonary artery systolic pressure (PASP) is associated with higher risks of graft dysfunction and resultant extracorporeal membrane oxygenation (ECMO) support. Methods. From 2016 to 2021, 102 adult recipients undergoing orthotopic heart transplantation at our institution were investigated (mean age, 48.5 ± 13.2 years; 22.5% female). This study cohort was stratified into 3 groups based on the PASP measured by right heart catheterization before surgery: &gt;50 mmHg, 35–50 mmHg, and &lt;35 mmHg. The primary end point was ECMO support after procedure. Results. ECMO was implemented in 24 (23.5%) patients due to difficult weaning from cardiopulmonary bypass or cardiac low output in the intensive care unit, which was likely to be associated with higher mortality ( P = 0.053 ). Age, gender, comorbidities, preoperative medications, and graft ischemia time were comparable across the 3 groups. The use of ECMO was significantly more common in patients with baseline PASP &gt;50 mmHg (11/36, 30.6%) and 35–50 mmHg (12/38, 31.6%), while only 1 (3.6%) patient with baseline PASP &lt;35 mmHg required ECMO support after transplant ( P = 0.007 ). Multivariate logistic models demonstrated that PASP (odds ratio = 2.34; P = 0.028 ) and cardiopulmonary bypass time (odds ratio = 1.01; P &lt; 0.001 ) were independent risk factors for postoperative ECMO. Conclusions. A mild elevation of pretransplant PASP (e.g., 35–50 mmHg) is related to low cardiac output and subsequent ECMO after heart transplantation, for which prompt administration of vasodilators before transplant may be protective.

Correlation of N-terminal-pro-brain natriuretic peptide with postoperative outcomes of older patients undergoing transcatheter aortic valve replacement.

Patients undergoing transcatheter aortic valve replacement surgery (TAVR) are typically older adults with multiple chronic diseases and therefore have a high surgical risk. The N-terminal of brain natriuretic peptide (BNP) and pro-BNP, referred to as NT-pro-BNP, is an easily measurable biomarker of heart failure. Studies on correlation between higher NT-pro-BNP levels and adverse prognoses after TAVR have yielded inconsistent results. Here, we investigated whether preoperative NT-pro-BNP levels are correlated with outcomes among older adults undergoing TAVR. This retrospective study included older adults with severe aortic stenosis (AS) who received TAVR from a medical center between January 2013 and June 2017. The patients' demographics, preoperative laboratory data, postoperative complications, and 1-year mortality were recorded. They were divided into two groups based on their preoperative NT-pro-BNP levels. The post-TAVR outcomes in the two groups were analyzed using a multivariate logistic regression analysis of the binary results. Of the 132 patients included (mean age: 81.5 ± 8.1 years; 47% men), 96 (72.7%) had preoperative NT-pro-BNP levels ≤ 4853 ng/L, and 36 (27.3%) had preoperative NT-pro-BNP levels > 4853 ng/L. The postoperative outcomes were significantly better in the NT-pro-BNP≤4853 group than in the NT-pro-BNP>4853 group: postoperative extracorporeal membrane oxygenation fittings (4.2% vs 16.7%, p = 0.025), number of days in hospital (17.5 ± 21.0 vs 27 ± 17.0, p = 0.009), in-hospital mortality (4.2% vs 16.7%, p = 0.025), and 1-year mortality (11.5% vs 38.9%, p = 0.001); the significant differences persisted after controlling for other variables. For older patients undergoing TAVR with NT-pro-BNP levels > 4853 ng/L, their postoperative outcomes and 1-year mortality were correlated. Thus, NT-pro-BNP is useful for the risk assessment of patients undergoing TAVR and should be regarded as a biomarker in future risk assessments.

Chicken or Egg: Tricuspid Regurgitation-The Cause or the Consequence of Post-Heart Transplant Allograft Dysfunction.

Tricuspid regurgitation (TR) is the most common valvular abnormality in cardiac transplant recipients.1 The causes of posttransplant TR are often obscure and can be multifactorial.2,3 The prognostic significance of posttransplant TR and the clinical implications of the severity of TR remain unclear and undefined.4-6 To clarify these questions, Bart et al7 conducted a retrospective study of their heart transplant patients over a 6-y period, examining transthoracic echocardiograms in 163 patients. Of these patients, 142 had a transthoracic echocardiograms before their first posttransplant endomyocardial biopsy (EMB). At month 0 posttransplant, 127 patients (78%) had no or mild TR before their first EMB, whereas 36 patients (22%) had moderate–severe TR.7 In patients with no or mild TR, 9 (7%) progressed to moderate–severe TR by 6 mo and 1 underwent tricuspid valve (TV) surgery.7 Of the patients with moderate–severe TR before the first biopsy, by 2 y, 3 had undergone TV surgery. Furthermore, in the moderate–severe TR before first biopsy group, postoperative extracorporeal membrane oxygenation (ECMO) use was significantly more common (78%; P < 0.05), as was rejection frequency (P = 0.02).7 Patients with late progressive moderate–severe TR had a significantly higher 2-y mortality than those who had moderate–severe TR immediately.7 Severe TR post–heart transplant is associated with a worse outcome8 although the clinical outcomes are otherwise variable.4 The consequences of severe TR can result in right ventricular dilatation with hepatic and renal congestion and subsequent dysfunction. Major causes of posttransplant TR include damage to the TV from the EMB and perioperative complications such as primary graft dysfunction (PGD), which often requires ECMO. This would explain the association of ECMO with moderate–severe TR. Additionally, rejection frequency was associated with greater severity of TR. This may be because of injury to the allograft from rejection as well as performing more EMB to make the diagnosis of rejection with concomitant damage to the TV. There has been some evidence that bicaval heart transplants are less likely to develop severe TR as opposed to the older biatrial transplant technique.9,10 However, the current study did not observe a difference. This retrospective study has significant limitations, which are clearly delineated by the authors. A retrospective, single-center study is likely not able to determine if there are specific factors that have causality in the development of TR, its severity, and its progression. The predominant use of the biatrial approach among this study’s patients would limit the ability to distinguish one surgical approach from another in terms of causality of TR. The increasing use of the bicaval approach may reduce the likelihood of developing TR or severe TR. The correlation of ECMO with the development of moderate–severe TR and worse prognoses would suggest that the presence of moderate–severe TR would be a consequence of severe allograft dysfunction posttransplant, necessitating resorting to ECMO for postoperative support. These patients would have worse prognoses on the basis of having PGD, and the severity of TR would, in essence, be an epiphenomenon and a surrogate marker of severe allograft dysfunction posttransplant, given the increased likelihood of developing hepatic and renal congestion and subsequent end-organ dysfunction with severe TR. We can conclude from the results of the current study that TR severity and progression are unsurprisingly associated with severe posttransplant allograft dysfunction with damage to the valve and allograft function. This and the concomitant TV valve damage would adversely affect posttransplant outcomes. The association of rejection frequency with TV severity could be associated with EMB-induced TR, which is also not surprising. What is missing from this study is a more prospective assessment of the relationship of pretransplant and posttransplant pulmonary hemodynamics and volume status to the development of and the severity of TR as well as the relationship with risk factors of PGD. This article serves as a starting point for future investigations. Ultimately, to resolve the questions raised by this article and to better understand the causes and risk factors of TR and prognostic factors of TR development and severity, a larger, prospective, multicenter study collecting echocardiographic information of TR severity, relationship of TR with type of transplant surgery performed, correlation of pulmonary hemodynamics with severity of TR, and prognosis and correlation of number of biopsies and rejection episodes with severity of TR should be performed. The care of transplant patients has changed with greater reliance on noninvasive biomarkers to assess the need for performing EMB, thus reducing the numbers of EMB. This may reduce the incidence and severity of TR. Given the large number of heart transplant programs in the United States that have switched to a biomarker-guided posttransplant strategy (donor-derived cell-free DNA, gene expression profiling) with biopsy minimization, it may be difficult to compare this approach with the more traditional biopsy-guided approach in terms of the impact on TR.