Association of procurement technique with organ yield and cost following donation after circulatory death.

Donation after circulatory death (DCD) could account for the largest expansion of the donor allograft pool in the contemporary era. However, the organ yield and associated costs of normothermic regional perfusion (NRP) compared to super-rapid recovery (SRR) with ex-situ normothermic machine perfusion, remain unreported. The Organ Procurement and Transplantation Network (December 2019 to June 2023) was analyzed to determine the number of organs recovered per donor. A cost analysis was performed based on our institution's experience since 2022. Of 43 502 donors, 30 646 (70%) were donors after brain death (DBD), 12 536 (29%) DCD-SRR and 320 (0.7%) DCD-NRP. The mean number of organs recovered was 3.70 for DBD, 3.71 for DCD-NRP (P < .001), and 2.45 for DCD-SRR (P < .001). Following risk adjustment, DCD-NRP (adjusted odds ratio 1.34, confidence interval 1.04-1.75) and DCD-SRR (adjusted odds ratio 2.11, confidence interval 2.01-2.21; reference: DBD) remained associated with greater odds of allograft nonuse. Including incomplete and completed procurement runs, the total average cost of DCD-NRP was $9463.22 per donor. By conservative estimates, we found that approximately 31 donor allografts could be procured using DCD-NRP for the cost equivalent of 1 allograft procured via DCD-SRR with ex-situ normothermic machine perfusion. In conclusion, DCD-SRR procurements were associated with the lowest organ yield compared to other procurement methods. To facilitate broader adoption of DCD procurement, a comprehensive understanding of the trade-offs inherent in each technique is imperative.

Reduced Morbidity and Mortality Associated With Minimally Invasive Single-vessel Coronary Artery Bypass Compared With Conventional Sternotomy.

OBJECTIVE: We aimed to describe the safety and clinical benefits of minimally invasive, nonsternotomy coronary artery bypass grafting (MICABG) using data from The Society of Thoracic Surgeons (STS) National Database. BACKGROUND: MICABG has gained popularity, owing to expected lower perioperative morbidity and shorter recovery. Despite this, concerns remain regarding anastomotic quality and the validity of proposed perioperative benefits. METHODS: We queried the STS National Database for all patients who underwent single-vessel coronary artery bypass grafting (CABG) from January 2014 to December 2016 to compare outcomes of MICABG with conventional CABG. Patients who underwent concomitant or emergent procedures were excluded. Propensity-weighted cohorts were compared by operative approach with adjustment for variability across institutions. RESULTS: Of 12,406 eligible patients, 2688 (21.7%) underwent MICABG, and 9818 (78.3%) underwent conventional CABG. Propensity weighting produced excellent balance in patient characteristics, including completeness of revascularization, body mass index, and STS predictive risk scores. MICABG was associated with significant reduction of in-hospital mortality [odds ratio (OR)=0.32, absolute reduction (AR)=0.91%, P <0.0001]; 30-day mortality (OR=0.51, AR=0.88%, P =0.001), duration of ventilation (8.62 vs 12.6 hours, P <0.0001), prolonged hospitalization (OR=0.77, AR=1.6, P =0.043), deep wound infection (OR=0.33, AR=0.68, P <0.004), postoperative transfusions (OR=0.52, AR=7.7%, P <0.0001), and STS composite morbidity (OR=0.72, AR=1.19%, P =0.008). Subgroup analysis of only off-pump left internal mammary artery-left anterior descending CABG showed similar findings. Major adverse cardiac events and graft occlusion did not differ between groups. CONCLUSIONS: MICABG is associated with lower mortality and perioperative morbidity compared with conventional sternotomy CABG. MICABG may have a role in treating single-vessel disease.

Extracorporeal membrane oxygenation for COVID-19: An evolving experience through multiple waves.

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) has shown variable results in COVID-19 pneumonia however, some evidence supports benefit. Here we compare our institution's ECMO outcomes across multiple waves of the COVID-19 pandemic. METHODS: All patients who received ECMO for COVID-19 between March 1, 2020, and March 1, 2021, were reviewed. Patients received venovenous (VV) or right ventricular assist device (RVAD/ECMO) ECMO. Early (March 1-July 6, 2020, Era 1) and late (July 7, 2020-March 1, 2021, Era 2) pandemic RVAD/ECMO patients were compared. RESULTS: Fifty-four patients received ECMO of which 16 (29.6%) patients received VV ECMO and 38 (70.4%) RVAD/ECMO. Median age was 53.0 years, body mass index 36.1 kg/m2 , 41.2% female, and 49% Caucasian. The most common pre-cannulation treatments included steroids (79.6%) and convalescent plasma (70.4%). Median time from admission to cannulation was 7.0 days. Median support time was 30.5 days (VV ECMO 35.0 days, RVAD/ECMO 26.0 days). In- hospital mortality was 42.6% (39.5% RVAD/ECMO, 50.0% VV ECMO). Significant morbidities included infection (80.8%), bleeding events (74.5%), and renal replacement therapy (30.8%). Cumulative mortality 120-days post-cannulation was 45.7% (VV ECMO 60.8%, RVAD/ECMO 40.0%). RVAD/ECMO Era 1 demonstrated a significantly lower cumulative mortality (16.2%) compared to Era 2 (60.4%). Competing risk analysis found age (HR 0.95, [95% CI 0.92, 0.98] p = 0.005) to be a protective factor for survival. CONCLUSION: ECMO support for COVID-19 is beneficial but carries significant morbidity. RVAD/ECMO support demonstrated consistent advantages in survival to VV-ECMO, but with declining efficacy across time during the COVID-19 pandemic.

Extracorporeal Membrane Oxygenation with Right Ventricular Assist Device for COVID-19 ARDS.

BACKGROUND: Right ventricular failure is an underrecognized consequence of COVID-19 pneumonia. Those with severe disease are treated with extracorporeal membrane oxygenation (ECMO) but with poor outcomes. Concomitant right ventricular assist device (RVAD) may be beneficial. METHODS: A retrospective analysis of intensive care unit patients admitted with COVID-19 ARDS (Acute Respiratory Distress Syndrome) was performed. Nonintubated patients, those with acute kidney injury, and age > 75 were excluded. Patients who underwent RVAD/ECMO support were compared with those managed via invasive mechanical ventilation (IMV) alone. The primary outcome was in-hospital mortality. Secondary outcomes included 30-d mortality, acute kidney injury, length of ICU stay, and duration of mechanical ventilation. RESULTS: A total of 145 patients were admitted to the ICU with COVID-19. Thirty-nine patients met inclusion criteria. Of these, 21 received IMV, and 18 received RVAD/ECMO. In-hospital (52.4 versus 11.1%, P = 0.008) and 30-d mortality (42.9 versus 5.6%, P= 0.011) were significantly lower in patients treated with RVAD/ECMO. Acute kidney injury occurred in 15 (71.4%) patients in the IMV group and zero RVAD/ECMO patients (P< 0.001). ICU (11.5 versus 21 d, P= 0.067) and hospital (14 versus 25.5 d, P = 0.054) length of stay were not significantly different. There were no RVAD/ECMO device complications. The duration of mechanical ventilation was not significantly different (10 versus 5 d, P = 0.44). CONCLUSIONS: RVAD support at the time of ECMO initiation resulted in the no secondary end-organ damage and higher in-hospital and 30-d survival versus IMV in specially selected patients with severe COVID-19 ARDS. Management of severe COVID-19 ARDS should prioritize right ventricular support.

Minimally invasive single-vessel left internal mammary to left anterior descending artery bypass grafting improves outcomes over conventional sternotomy: A single-institution retrospective cohort study.

BACKGROUND: Coronary artery bypass grafting (CABG) can be performed through a variety of approaches. Minimally-invasive CABG (MICABG) may reduce perioperative morbidity. Previous results demonstrate improved perioperative outcomes; however, adoption has been limited. METHODS: The Society of Thoracic Surgeons (STS) database and electronic medical record at a single institution were reviewed for isolated left internal mammary to left anterior descending artery (LIMA-LAD) bypass procedures performed between 2011 and 2018. Patients were grouped on the basis of operative approach, comparing sternotomy to non-sternotomy (minimally-invasive). Patient characteristics, perioperative variables, and short- and long-term outcomes were compared. Primary outcomes included mortality and major adverse cardiac events (MACE). Secondary outcomes were morbidity. RESULTS: A total of 42 MICABG and 54 conventional LIMA-LAD procedures were performed with 95.2% of MICABG procedures performed by two surgeons. MICABG were more often elective (83.3 vs 38.9%, P < .001). STS risk scores predicted equitable mortality and morbidity for MICABG dependent on operative indication. MICABG was associated with fewer pulmonary complications (0.0 vs 11.1%, P = .033), in-hospital events (11.9 vs 37.0%, P = .005), and shorter intensive care unit (34.1 vs 66.0 hours, P = .022) and total length of stay (3.7 vs 6.5 days, P = .002). There were no observed strokes, myocardial infarctions, or reoperations. MICABG patients demonstrated reduced thirty-day mortality (0.0 vs 10.9%, P = .036) and improved Kaplan-Meier 5-year (95.2 vs 77.9%, P = .016) and MACE-free survival (89.2 vs 63.9%, P = .010). CONCLUSIONS: Minimally-invasive LIMA-LAD CABG demonstrates improved early postoperative morbidity and a long-term mortality benefit. In select patients, minimally-invasive approaches to single-vessel grafting may be beneficial when performed by experienced surgeons in the elective setting.

Characterization of binding mode of action of a blocking anti-platelet-derived growth factor (PDGF)-B monoclonal antibody, MOR8457, reveals conformational flexibility and avidity needed for PDGF-BB to bind PDGF receptor-ß.

Platelet derived growth factor-BB (PDGF-BB) is an important mitogen and cell survival factor during development. PDGF-BB binds PDGF receptor-ß (PDGFRß) to trigger receptor dimerization and tyrosine kinase activation. We present the pharmacological and biophysical characterization of a blocking PDGF-BB monoclonal antibody, MOR8457, and contrast this to PDGFRß. MOR8457 binds to PDGF-BB with high affinity and selectivity, and prevents PDGF-BB induced cell proliferation competitively and with high potency. The structural characterization of the MOR8457-PDGF-BB complex indicates that MOR8457 binds with a 2:1 stoichiometry, but that binding of a single MOR8457 moiety is sufficient to prevent binding to PDGFRß. Comparison of the MOR8457-PDGF-BB structure with that of the PDGFRß-PDGF-BB complex suggested the potential reason for this was a substantial bending and twisting of PDGF-BB in the MOR8457 structure, relative to the structures of PDGF-BB alone, bound to a PDGF-BB aptamer or PDGFRß, which makes it nonpermissive for PDGFRß binding. These biochemical and structural data offer insights into the permissive structure of PDGF-BB needed for agonism as well as strategies for developing specific PDGF ligand antagonists.

Impact of denervated myocardium on improving risk stratification for sudden cardiac death.

Between 184,000 and 462,000 Americans die suddenly each year. Fifty percent to 70% of these deaths are due to ventricular tachycardia/fibrillation (VT/VF). We tested whether hibernating myocardium or myocardial sympathetic denervation identifies patients at high-risk for developing VT/VF independently of ejection fraction (EF). Positron emission tomography (PET) was used to quantify myocardial sympathetic denervation ((11)C-meta-hydroxyephedrine [(11)C-HED]), perfusion ((13)N-ammonia), and viability (insulin-stimulated (18)F-2-deoxyglucose [(18)FDG]) in patients with ischemic cardiomyopathy (EF < 35%) eligible for a primary prevention implantable cardioverter defibrillator (ICD). The primary end-point was sudden cardiac arrest (SCA) defined as arrhythmic death or ICD discharge for VT/VF > 240 bpm. Volumes of total denervated (P = .001) and viable denervated myocardium ((11)C-HED-(18)FDG mismatch, P = .03) predicted SCA, whereas hibernating and infarcted myocardium did not. Multivariate analysis identified four independent predictors of SCA: denervated myocardium > 37.6% of left ventricule (LV), LV end-diastolic volume > 98 mL/m(2), creatinine level > 1.49 mg/dL, and no angiotensin- inhibition therapy. Denervated myocardium had a hazard ratio of 3.5 for SCA (10.3%/year vs. 3.0%/year, p=0.001). Absence of all four factors predicted low risk (44% of cohort; SCA <1%/y) whereas two or more factors identified subjects at high-risk (20% of cohort; SCA 12%/y). Denervated myocardium quantified using PET strongly predicts risk of SCA, and is independent of EF, infarct volume, and other clinical variables.

Interventional radiology workflow management in the electronic medical record.

The electronic medical record (EMR) has significantly improved efficiency in many areas of radiology workflow. Following implementation of an electronic protocol selection process for cross-sectional imaging at the University of Colorado Hospital, the interventional radiology (IR) division desired to have a similar tool. Evaluation of the IR workflow demonstrated the need for a multilayered solution, which accounted for consultation, physician review, authorization and scheduling, pre-procedural nursing evaluation, physician rounding, and resource allocation and prioritization. This paper outlines the rationale for and components of this process.

Noteworthy in Cardiothoracic Surgery 2023.

Noteworthy in Cardiothoracic Surgery 2023 summarizes a few of the most high-impact trials and provocative trends in cardiothoracic surgery and transplantation this past year. Transplantation using organs procured from donation after circulatory death (DCD) continues to increase, and the American Society of Transplant Surgeons released recommendations on best practices in 2023. We review a summary of data on the impact of DCD on heart and lung transplantation. There has been increased interest in extracorporeal life support (ECLS), particularly after the COVID-19 pandemic, and we review the results of the highly discussed ECLS-SHOCK trial, which randomized patients in cardiogenic shock with planned revascularization to ECLS vs usual care. With improving survival outcomes in complex aortic surgery, there is a need for higher-quality evidence to guide which cooling and cerebral perfusion strategies may optimize cognitive outcomes in these patients. We review the short-term outcomes of the GOT ICE trial (Cognitive Effects of Body Temperature During Hypothermic Circulatory Arrest), a multicenter, randomized controlled trial of three different nadir temperatures, evaluating outcomes in cognition and associated changes in functional magnetic resonance imaging. Finally, both the Society of Thoracic Surgeons (STS) and the American College of Cardiology, American Heart Association, American College of Chest Physicians and Heart Rhythm Society (ACC/AHA/ACCP/HRS) updated atrial fibrillation guidelines in 2023, and we review surgically relevant updates to the guidelines and the evidence behind them.