Utility of a fusion protein T-cell co-stimulation blocker Belatacept in heart transplant recipients: Real world experience from a high volume center.

BACKGROUND: Belatacept (BTC), a fusion protein, selectively inhibits T-cell co-stimulation by binding to the CD80 and CD86 receptors on antigen-presenting cells (APCs) and has been used as immunosuppression in adult renal transplant recipients. However, data regarding its use in heart transplant (HT) recipients are limited. This retrospective cohort study aimed to delineate BTC's application in HT, focusing on efficacy, safety, and associated complications at a high-volume HT center. METHODS: A retrospective cohort study was conducted of patients who underwent HT between January 2017 and December 2021 and subsequently received BTC as part of their immunosuppressive regimen. Twenty-one HT recipients were identified. Baseline characteristics, history of rejection, and indication for BTC use were collected. Outcomes included renal function, graft function, allograft rejection and mortality. Follow-up data were collected through December 2023. RESULTS: Among 776 patients monitored from January 2017 to December 2021 21 (2.7%) received BTC treatment. Average age at transplantation was 53 years (± 12 years), and 38% were women. BTC administration began, on average, 689 [483, 1830] days post-HT. The primary indications for BTC were elevated pre-formed donor-specific antibodies in highly sensitized patients (66.6%) and renal sparing (23.8%), in conjunction with reduced calcineurin inhibitor dosage. Only one (4.8%) patient encountered rejection within a year of starting BTC. Graft function by echocardiography remained stable at 6 and 12 months posttreatment. An improvement was observed in serum creatinine levels (76.2% of patients), decreasing from a median of 1.58 to 1.45 (IQR [1.0-2.1] to [1.1-1.9]) over 12 months (p = .054). eGFR improved at 3 and 6 months compared with 3 months pre- BTC levels; however, this was not statistically significant (p = .24). Treatment discontinuation occurred in seven patients (33.3%) of whom four (19%) were switched back to full dose CNI. Infections occurred in 11 patients (52.4%), leading to BTC discontinuation in 4 patients (19%). CONCLUSION: In this cohort, BTC therapy was used as alternative immunosuppression for management of highly sensitized patients or for renal sparing. BTC therapy when combined with CNI dose reduction resulted in stabilization in renal function as measured through renal surrogate markers, which did not, however, reach statistical significance. Patients on BTC maintained a low rejection rate and preserved graft function. Infections were common during BTC therapy and were associated with medication pause/discontinuation in 19% of patients. Further randomized studies are needed to assess the efficacy and safety of BTC in HT recipients.

Long-term outcomes for pediatric heart transplant recipients transitioning to adult care teams.

BACKGROUND: There are limited data evaluating the success of a structured transition plan specifically for pediatric heart transplant (HT) recipients following their transfer of care to an adult specialist. We sought to identify risk factors for poor adherence, graft failure, and mortality following the transfer of care to adult HT care teams. METHODS: We retrospectively reviewed all patients who underwent transition from the pediatric to adult HT program at our center between January 2011 and June 2021. Demographic characteristics, comorbid conditions, and psychosocial history were collected at the time of HT, the time of transition, and the most recent follow-up. Adverse events including mortality, graft rejection, infection, and renal function were also captured before and after the transition. RESULTS: Seventy-two patients were identified (54.1% male, 54.2% Caucasian). Mean age at the time of transition was 23 years after a median of 11.6 years in the pediatric program. The use of calcineurin inhibitors was associated with reduced mortality (HR .04, 95% CI .0-.6, p = .015), while prior psychiatric hospitalization (HR 45.3, 95% CI, 6.144-333.9, p = .0001) was associated with increased mortality following transition. Medication nonadherence and young age at the time of transition were markers for high-risk individuals prior to the transition of care. CONCLUSIONS: Transition of HT recipients from a pediatric program to an adult program occurs during a vulnerable time of emerging adulthood, and we have identified risk factors for mortality following transition. Development of a formalized transition plan with a large multidisciplinary team with focused attention on high-risk patients, including those with psychiatric comorbidities, may favorably influence outcomes.

Hemodynamic Optimization by Invasive Ramp Test in Patients Supported With HeartMate 3 Left Ventricular Assist Device.

In patients supported by the HeartMate 3 left ventricular assist device (HM3 LVAD), pump speed adjustments may improve hemodynamics. We investigated the hemodynamic implications of speed adjustments in HM3 recipients undergoing hemodynamic ramp tests. Clinically stable HM3 recipients who underwent routine invasive hemodynamic ramp tests between 2015 and 2022 at our center were included. Filling pressure optimization, defined as central venous pressure (CVP) <12 mm Hg and pulmonary capillary wedge pressure (PCWP) <18 mm Hg, was assessed at baseline and final pump speeds. Patients with optimized pressures were compared to nonoptimized patients. Overall 60 HM3 recipients with a median age of 62 years (56, 71) and time from LVAD implantation of 187 days (124, 476) were included. Optimized filling pressures were found in 35 patients (58%) at baseline speed. Speed was adjusted in 84% of the nonoptimized patients. Consequently, 39 patients (65%) had optimized pressures at final speed. There were no significant differences in hemodynamic findings between baseline and final speeds (p > 0.05 for all). Six and 12 month readmission-free rates were higher in optimized compared with nonoptimized patients (p = 0.03 for both), predominantly due to lower cardiac readmission-free rates (p = 0.052). In stable outpatients supported with HM3 who underwent routine ramp tests, optimized hemodynamics were achieved in only 2 of 3 of the patients. Patients with optimized pressures had lower all-cause readmission rates, primarily driven by fewer cardiac-related hospitalizations.

Impact of Interventricular Interaction on Ventricular Function: Insights From Right Ventricular Pressure-Volume Analysis.

BACKGROUND: Interventricular interactions may be responsible for the decline in ventricular performance observed in various disease states that primarily affect the contralateral ventricle. OBJECTIVES: This study sought to quantify the impact of such interactions on right ventricular (RV) size and function using clinically stable individuals with left ventricular assist devices (LVADs) as a model for assessing RV hemodynamics while LV loading conditions were acutely manipulated by changing device speed during hemodynamic optimization studies (ie, ramp tests). METHODS: The investigators recorded RV pressure-volume loops with a conductance catheter at various speeds during ramp tests in 20 clinically stable HeartMate3 recipients. RESULTS: With faster LVAD speeds and greater LV unloading, indexed RV end-diastolic volume increased (72.28 ± 15.07 mL at low speed vs 75.95 ± 16.90 at high speed; P = 0.04) whereas indexed end-systolic volumes remained neutral. This resulted in larger RV stroke volumes and shallower end-diastolic pressure-volume relationships. Concurrently, RV end-systolic pressure decreased (31.58 ± 9.75 mL at low speed vs 29.58 ± 9.41 mL at high speed; P = 0.02), but contractility, as measured by end-systolic elastance, did not change significantly. The reduction in RV end-systolic pressure was associated with a reduction in effective arterial elastance from 0.65 ± 0.43 mm Hg/mL at low speed to 0.54 ± 0.33 mm Hg/mL at high speed (P = 0.02). CONCLUSIONS: Interventricular interactions resulted in improved RV compliance, diminished afterload, and did not reduce RV contractility. These data challenge the prevailing view that interventricular interactions compromise RV function, which has important implications for the understanding of RV-LV interactions in various disease states, including post-LVAD RV dysfunction.

The Hemodynamic Effects of Aortic Regurgitation in Patients Supported by a HeartMate 3 Left Ventricular Assist Device.

BACKGROUND: Aortic regurgitation (AR) is a common complication following left ventricular assist device (LVAD) implantation. We evaluated the hemodynamic implications of AR in patients with HeartMate 3 (HM3) LVAD at baseline and in response to speed changes. METHODS AND RESULTS: Clinically stable outpatients supported by HM3 who underwent a routine hemodynamic ramp test were retrospectively enrolled in this analysis. Patients were stratified based on the presence of at least mild AR at baseline speed. Hemodynamic and echocardiographic parameters were compared between the AR and non-AR groups. Sixty-two patients were identified. At the baseline LVAD speed, 29 patients (47%) had AR, while 33 patients (53%) did not. Patients with AR were older and supported on HM3 for a longer duration. At baseline speed, all hemodynamic parameters were similar between the groups including central venous pressure, pulmonary capillary wedge pressure, pulmonary arterial pressures, cardiac output and index, and pulmonary artery pulsatility index (p > 0.05 for all). During the subacute assessment, AR worsened in some, but not all, patients, with increases in LVAD speed. There were no significant differences in 1-year mortality or hospitalization rates between the groups, however, at 1-year, ≥ moderate AR and right ventricular failure (RVF) were detected in higher rates among the AR group compared to the non-AR group (45% vs. 0%; p < 0.01, and 75% vs. 36.8%; p = 0.02, respectively). CONCLUSIONS: In a cohort of stable outpatients supported with HM3 who underwent a routine hemodynamic ramp test, the presence of mild or greater AR did not impact the ability of HM3 LVADs to effectively unload the left ventricle during early subacute assessment. Although the presence of AR did not affect mortality and hospitalization rates, it resulted in higher rates of late hemodynamic-related events in the form of progressive AR and RVF.

Acute kidney injury during extracorporeal life support in cardiogenic shock: Does flow matter?

BACKGROUND: This study examines the role of extracorporeal life support flow in the development of acute kidney injury in cardiogenic shock. METHODS: We performed a retrospective analysis of 465 patients placed on extracorporeal life support at our institution between January 2015 and December 2020 for cardiogenic shock. Flow index was calculated by dividing mean flow by body surface. Stages of acute kidney injury were determined according to Kidney Disease: Improving Global Outcomes (KDIGO) organization guidelines. RESULTS: There were 179 (38.5%) patients who developed acute kidney injury, 63.1% of which were classified as Stage 3--the only subgroup associated with 1-year mortality (hazard ratio = 2.03, p < .001). Risk of kidney injury increased up to a flow index of 1.6 L/min/m2, and kidney injury was more common among patients with flow index greater than 1.6 L/min/m2 (p = .034). Those with kidney injury had higher baseline lactate levels (4.4 vs 3.1, p = .04), and Stage 3 was associated wit higher baseline creatinine (p < .001). CONCLUSIONS: In our cohort, kidney injury was common and Stage 3 kidney injury was associated with worse outcomes compared to other stages. Low flow was not associated with increased risk of kidney injury. Elevated baseline lactate and creatinine among patients with acute kidney injury suggest underlying illness severity, rather than flow, may influence kidney injury risk.

Fulminant myocarditis proven by early biopsy and outcomes.

BACKGROUND AND AIMS: While endomyocardial biopsy (EMB) is recommended in adult patients with fulminant myocarditis, the clinical impact of its timing is still unclear. METHODS: Data were collected from 419 adult patients with clinically suspected fulminant myocarditis admitted to intensive care units across 36 tertiary centres in 15 countries worldwide. The diagnosis of myocarditis was histologically proven in 210 (50%) patients, either by EMB (n = 183, 44%) or by autopsy/explanted heart examination (n = 27, 6%), and clinically suspected cardiac magnetic resonance imaging confirmed in 96 (23%) patients. The primary outcome of survival free of heart transplantation (HTx) or left ventricular assist device (LVAD) at 1 year was specifically compared between patients with early EMB (within 2 days after intensive care unit admission, n = 103) and delayed EMB (n = 80). A propensity score-weighted analysis was done to control for confounders. RESULTS: Median age on admission was 40 (29-52) years, and 322 (77%) patients received temporary mechanical circulatory support. A total of 273 (65%) patients survived without HTx/LVAD. The primary outcome was significantly different between patients with early and delayed EMB (70% vs. 49%, P = .004). After propensity score weighting, the early EMB group still significantly differed from the delayed EMB group in terms of survival free of HTx/LVAD (63% vs. 40%, P = .021). Moreover, early EMB was independently associated with a lower rate of death or HTx/LVAD at 1 year (odds ratio of 0.44; 95% confidence interval: 0.22-0.86; P = .016). CONCLUSIONS: Endomyocardial biopsy should be broadly and promptly used in patients admitted to the intensive care unit for clinically suspected fulminant myocarditis.

Pumping for Two: Pregnancy in Patients Supported With a Left Ventricular Assist Device.

This review discusses the challenges and outcomes associated with pregnancy during left ventricular assist device (LVAD) support. Women account for a third of the heart failure population in the United States. Left ventricular assist devices have emerged as a safe and effective treatment option for patients with advanced heart failure. Pregnancy during LVAD support can occur, and it presents significant risks to both mother and fetus, including hemodynamic stress, thrombotic events, medication-associated teratogenicity, and uterine impingement. This literature review identified 10 cases of confirmed pregnancy during LVAD support, of which eight resulted in successful births. Maternal and fetal mortality occurred in one case, and there was a spontaneous abortion in one case. The review highlights the importance of a multidisciplinary approach, promotion of shared decision-making, thoughtful anticoagulation, adjustment of LVAD speed, and medication optimization to maintain hemodynamic support during pregnancy. Hemodynamic changes during pregnancy include increased cardiac output, heart rate, and plasma volume, as well as decreased systemic vascular resistance, which can impact LVAD support. Despite reduced pulsatility in LVAD-supported patients, ovulation and reproductive capacity might be preserved, and viable pregnancies may be achieved with appropriate management. The review provides insights into the risks and considerations for a viable pregnancy during LVAD support, including the need for ongoing research to inform joined decision-making.

Age and associated outcomes among patients receiving venoarterial extracorporeal membrane oxygenation-analysis of the Extracorporeal Life Support Organization registry.

PURPOSE: Venoarterial extracorporeal membrane oxygenation (V-A ECMO) can be used to support severely ill patients with cardiogenic shock. While age is commonly used in patient selection, little is known regarding its association with outcomes in this population. We sought to evaluate the association between increasing age and outcomes following V-A ECMO. METHODS: We used individual-level patient data from 440 centers in the international Extracorporeal Life Support Organization registry. We included all adult patients receiving V-A ECMO from 2017 to 2019. The primary outcome was hospital mortality. Secondary outcomes included a composite of complications following initiation of V-A ECMO. We conducted Bayesian analyses of the relationship between increasing age and outcomes of interest. RESULTS: We included 15,172 patients receiving V-A ECMO. Of these, 8172 (53.9%) died in hospital. For the analysis conducted using weakly informed priors, and as compared to the reference category of age 18-29, the age bracket of 30-39 (odds ratio [OR] 0.94, 95% credible interval [CrI] 0.79-1.10) was not associated with hospital mortality, but age brackets 40-49 (odds ratio [OR] 1.26, 95% CrI: 1.08-1.47), 50-59 (OR 1.78, 95% CrI: 1.55-2.06), 60-69 (OR 2.24, 95% CrI: 1.94-2.59), 70-79 (OR 2.90, 95% CrI: 2.49-3.39) and ≥ 80 (OR 4.02, 95% CrI: 3.13-5.20) were independently associated with increasing hospital mortality. Similar results were found in the analysis conducted with an informative prior, as well as between increasing age and post-ECMO complications. CONCLUSIONS: Among patients receiving V-A ECMO for cardiogenic shock, increasing age is strongly associated with increasing odds of death and complications, and this association emerges as early as 40 years of age.

The utilization of molecular microscope in management of heart transplant recipients in the era of noninvasive monitoring.

INTRODUCTION: Monitoring for graft rejection is a fundamental tenet of post-transplant follow-up. In heart transplantation (HT) in particular, rejection has been traditionally assessed with endomyocardial biopsy (EMB). EMB has potential complications and noted limitations, including interobserver variability in interpretation. Additional tests, such as basic cardiac biomarkers, cardiac imaging, gene expression profiling (GEP) scores, donor-derived cell-free DNA (dd-cfDNA) and the novel molecular microscope diagnostic system (MMDx) have become critical tools in rejection surveillance beyond standard EMB. METHODS: This paper describes an illustrative case followed by a review of MMDx within the context of other noninvasive screening modalities for rejection. CONCLUSIONS: We suggest MMDx be used to assist with early detection of rejection in cases of discordance between EMB and other noninvasive studies.

How I manage differential gas exchange in peripheral venoarterial extracorporeal membrane oxygenation.

Dual circulation is a common but underrecognized physiological occurrence associated with peripheral venoarterial extracorporeal membrane oxygenation (ECMO). Competitive flow will develop between blood ejected from the heart and blood travelling retrograde within the aorta from the ECMO reinfusion cannula. The intersection of these two competitive flows is referred to as the "mixing point". The location of this mixing point, which depends upon the relative strengths of the native and extracorporeal pumps, will determine which regions of the body are perfused with blood ejected from the left ventricle and which regions are perfused by reinfused blood from the ECMO circuit, effectively establishing dual circulations. Because gas exchange within these circulations is dictated by the native lungs and membrane lung, respectively, oxygenation and carbon dioxide removal may differ between regions-depending on how well gas exchange is preserved within each circulation-potentially leading to differential oxygenation or differential carbon dioxide, each of which may have important clinical implications. In this perspective, we address the identification and management of dual circulation and differential gas exchange through various clinical scenarios of venoarterial ECMO. Recognition of dual circulation, proper monitoring for differential gas exchange, and understanding the various strategies to resolve differential oxygenation and carbon dioxide may allow for more optimal patient management and improved clinical outcomes.

Long-term outcomes of patients bridged to recovery with venoarterial extracorporeal life support.

OBJECTIVE: Our study examines the long-term outcomes of patients discharged from the hospital without heart replacement therapy (HRT) after recovery from cardiogenic shock using venoarterial extracorporeal life support (VA-ECLS). METHODS: We retrospectively reviewed 615 cardiogenic shock patients who recovered from VA-ECLS at our institution between January 2015 and July 2021. Of those, 166 patients (27.0%) who recovered from VA-ECLS without HRT were included in this study. Baseline characteristics, discharge labs, vitals, electrocardiograms and echocardiograms were assessed. Patients were contacted to determine vital status. The primary outcome was post-discharge mortality. RESULTS: Of 166 patients, 158 patients (95.2%) had post-discharge follow-up, with a median time of follow-up of 2 years (IQR: [1 year, 4 years]). At discharge, the median ejection fraction (EF) was 52.5% (IQR: [32.5, 57.5]). At discharge, 92 patients (56%) were prescribed ß-blockers, 28 (17%) were prescribed an ACE inhibitor, ARB or ARNI, and 50 (30%) were prescribed loop diuretics. Kaplan-Meier analysis showed a 1-year survival rate of 85.6% (95% CI: [80.1%, 91.2%]) and a 5-year survival rate of 60.6% (95% CI: [49.9%, 71.3%]). A Cox regression model demonstrated that a history of congestive heart failure (CHF) was strongly predictive of increased mortality hazard (HR = 1.929; p = 0.036), while neither discharge EF nor etiology of VA-ECLS were associated with increased post-discharge mortality. CONCLUSIONS: Patients discharged from the hospital after full myocardial recovery from VA-ECLS support without HRT should have close outpatient follow-up due to the risk of recurrent heart failure and increased mortality in these patients.

Aortic Root Thrombosis in patients with HeartMate 3 left ventricular assist device support.

BACKGROUND: Aortic root thrombosis(ART) is a complication of continuous-flow left ventricular assist device therapy. However, the incidence and related complications of ART in HeartMate 3 (HM3) patients remain unknown. METHODS: Patients who underwent HM3 implantation from November 2014 to August 2020 at a quaternary academic medical center were included. Demographics and outcomes were abstracted from the medical record. Echocardiograms and contrast-enhanced computed tomography studies were reviewed to identify patients who developed ART and/or moderate or greater aortic insufficiency (AI) on HM3 support. RESULTS: The study cohort included 197 HM3 patients with a median postimplant follow-up of 17.5 months. Nineteen patients (9.6%) developed ART during HM3 support, and 15 patients (7.6%) developed moderate or greater AI. Baseline age, gender, race, implantation strategy, and INTERMACS classification were similar between the ART and no-ART groups. ART was associated with an increased risk of death, stroke, or aortic valve (AV) intervention (subhazard ratio [SHR] 3.60 [95% confidence interval (CI) 1.71-7.56]; p = 0.001) and moderate or greater AI (SHR 11.1 [CI 3.60-34.1]; p < 0.001) but was not associated with a statistically significantly increased risk of death or stroke on HM3 support (2.12 [0.86-5.22]; p = 0.10). Of the 19 patients with ART, 6 (31.6%) developed moderate or greater AI, necessitating more frequent AV interventions (ART: 5 AV interventions [3 surgical repairs, 1 surgical replacement, 1 transcatheter replacement; 26.3%]; no-ART: 0). CONCLUSIONS: Nearly 10% of HM3 patients developed ART during device support. ART was associated with increased risk of a composite end-point of death, stroke, or AV intervention as well as moderate or greater AI.

New system, old problem: Increased wait time for high-priority transplant candidates.

The 2018 heart allocation policy sought to improve risk stratification and reduce waitlist mortality for the sickest patients. This study sought to evaluate changes in wait times for the highest priority patients since policy implementation. All adult single-organ transplant recipients were identified in the United Network for Organ Sharing registry from October 18, 2018, to July 8, 2022, and separated into 4 periods. Outcomes were compared by blood type and UNOS region. Over the study period, 897 of 9,143 patients were listed as status 1 with no significant change in median wait time by blood type or region. More patients were listed as status 2 (4,523/9,143), and each subsequent period postpolicy change was associated with a 4.2-day increase in mean status 2 waitlist time (95% confidence interval 3.0-5.5, p < 0.0001). Wait times were longest for candidates with blood type O and shortest for AB & A. Regional variations continued, however, wait time increased in every region over time.

Impact of preheart transplant spirometry and DCLO measurement on post-transplant pulmonary outcomes.

BACKGROUND: Pulmonary function tests (PFT) are a frequent component of heart transplant evaluation. In cardiac surgery abnormal PFTs, especially reduced DLCO, have been associated with poor outcomes. We sought to evaluate the impact of pretransplant PFTs on post-transplant pulmonary outcomes and patient survival. METHODS: Among the 652 adult heart transplant recipients between January 1, 2010 and July 31, 2021, 462 had PFTs and constituted the patient cohort. Obstructive ventilatory defects (OVD), restrictive ventilatory defects (RVD), and reduced DLCO were defined according to established criteria. The primary outcome was the combined endpoint of a post-transplant pulmonary complication defined as reintubation, postoperative pneumonia, prolonged intubation, or tracheostomy. Secondary outcomes included 90-day all-cause mortality, length of stay, and the odds of individual pulmonary complications. Kaplan-Meier survival analysis, multivariable Cox proportional-hazards regression, and multivariable logistic regression were performed to compare outcomes between the groups. RESULTS: Patients with severe OVD (OR 1.48, 95% CI 1.18-5.23, p = 0.02) or severely reduced DLCO (OR 1.95, 95% CI 1.19-3.20, p = 0.008) had increased odds of post-transplant pulmonary complications. Following multivariable adjustment, severe OVD (aOR 2.67, 95% CI 1.15-6.19, p = 0.02) and severely reduced DLCO (aOR 1.79, 95% CI 1.05-3.04) remained strongly associated with post-transplant pulmonary complications. Patients with any degree of extrinsic RVD, moderate or less OVD, or moderately reduced DLCO or less did not have increased odds of post-transplant pulmonary complications. Ninety-day post-transplant survival was significantly reduced for both severe OVD (97.2% vs 86.5%, p = 0.04) and severely reduced DLCO (97.3% vs 90.4%, p = 0.004). Post-transplant ICU and hospital length of stay were nominally longer for both groups as well. CONCLUSIONS: Severe OVD or severely reduced DLCO on preheart transplant PFTs were associated with increased odds of post-transplant pulmonary complications and early mortality.

Early post-transplant leukopenia in heart transplant recipients and its impact on outcomes.

BACKGROUND: Leukopenia in the early period following heart transplantation (HT) is not well-studied. The aim of this study was to evaluate risk factors for the development of post-transplant leukopenia and its consequences for HT recipients. METHODS: Adult patients at a large-volume transplant center who received HT between January 1, 2010 and December 31, 2020 were included. The incidence of leukopenia (WBC ≤3 × 103 /µL) in the first 90-days following HT, individual risk factors, and its effect on 1-year outcomes were evaluated. RESULTS: Of 506 HT recipients, 184 (36%) developed leukopenia within 90-days. Median duration of the first leukopenia episode was 15.5 days (IQR 8-42.5 days). Individuals who developed leukopenia had lower pre-transplant WBC counts compared to those who did not (6.1 × 103 /µL vs. 6.9 × 103 /µL, p = .02). Initial immunosuppressive and infectious chemoprophylactic regimens were not significantly different between groups. Early leukopenia was associated with a higher mortality at 1-year (6.6% vs. 2.1%, p = .008; adjusted HR 3.0) and an increased risk of recurrent episodes. Rates of infection and rejection were not significantly different between the two groups. CONCLUSIONS: Leukopenia in the early period following HT is common and associated with an increased risk of mortality. Further study is needed to identify individuals at highest risk for leukopenia prior to transplant and optimize immunosuppressive and infectious chemoprophylactic regimens for this subgroup.

Society for Cardiovascular Angiography and Interventions Shock Classification to Stratify Outcomes of Extracorporeal Membrane Oxygenation.

We applied the Society for Cardiovascular Angiography and Interventions (SCAI) schema to cardiogenic shock (CS) patients treated with venoarterial extracorporeal membrane oxygenation (VA-ECMO) to assess performance in this high acuity group of patients. Records of adult patients receiving VA-ECMO for CS at our institution from 01/2015 to 12/2019 were reviewed. Post-cardiotomy and noncardiogenic shock patients were excluded. A total of 245 patients were included, with a median age of 59 years [IQR: 48-67]; 159 (65%) were male. There were 34 (14%) patients in Stage C, 82 (33%) in D, and 129 (53%) in E. Of E patients, 88 (68%) were undergoing cardiopulmonary resuscitation. Median ECMO duration decreased with stage (C:7, D:6, E:4 days, P < 0.001). In-hospital mortality increased (C:35%, D:56%, E:71%, P < 0.001) and myocardial recovery decreased with stage (C:65%, D:35%, E:30%, P < 0.001). Acute kidney injury (C:35%, D:45%, E:54%, P = 0.045), acute liver failure (C:32%, D:66%, E:76%, P < 0.001), and infection (C:35%, D:28%, E:16%, P = 0.004) varied among groups. Multivariable analysis revealed age (HR=1.02), male sex (HR=0.62), and E classification (HR=2.69) as independently associated with 1-year mortality. Competing-risks regression identified D (SHR=0.53) and E classification (SHR=0.45) as inversely associated with myocardial recovery. In patients treated with VA-ECMO for CS, the SCAI classification provided robust risk stratification.

Continuous near-infrared reflectance spectroscopy monitoring to guide distal perfusion can minimize limb ischemia surgery for patients requiring femoral venoarterial extracorporeal life support.

BACKGROUND: Patients requiring femoral venoarterial (VA) extracorporeal life support (ECLS) are at risk of distal lower limb hypoperfusion and ischemia of the cannulated leg. In the present study, we evaluated the effect of using continuous noninvasive lower limb oximetry with near-infrared reflectance spectroscopy (NIRS) to detect tissue hypoxia and guide distal perfusion catheter (DPC) placement on the rates of leg ischemia requiring surgical intervention. METHODS: We performed a retrospective analysis of patients who had undergone femoral VA-ECLS at our institution from 2010 to 2014 (pre-NIRS era) and 2017 to 2021 (NIRS era). Patients who had undergone cannulation during the 2015 to 2016 transition era were excluded. The baseline characteristics, short-term outcomes, and ischemic complications requiring surgical intervention (eg, fasciotomy, thrombectomy, amputation, exploration) were compared across the two cohorts. RESULTS: Of the 490 patients included in the present study, 141 (28.8%) and 349 (71.2%) had undergone cannulation before and after the routine use of NIRS to direct DPC placement, respectively. The patients in the NIRS cohort had had a greater incidence of hyperlipidemia (53.7% vs 41.1%; P = .015) and hypertension (71.4% vs 60%; P = .020) at baseline, although they were less likely to have been supported with an intra-aortic balloon pump before ECLS cannulation (26.9% vs 37.6%; P = .026). These patients were also more likely to have experienced cardiac arrest (22.9% vs 7.8%; P ≤ .001) and a pulmonary cause (5.2% vs 0.7%; P = .04) as an indication for ECLS, with ECLS initiated less often for acute myocardial infarction (15.8% vs 34%; P ≤ .001). The patients in the NIRS cohort had had a smaller arterial cannula size (P ≤ .001) and a longer duration of ECLS support (5 vs 3.25 days; P ≤ .001) but significantly lower rates of surgical intervention for limb ischemia (2.6% vs 8.5%; P = .007) despite comparable rates of DPC placement (49.1% vs 44.7%; P = .427), with only two patients (1.1%) not identified by NIRS ultimately requiring surgical intervention. CONCLUSIONS: The use of a smaller arterial cannula (≤15F) and continuous NIRS monitoring to guide selective insertion of DPCs could be a valid and effective strategy associated with a reduced incidence of ischemic events requiring surgical intervention.

Outflow Graft Narrowing of the HeartMate 3 Left Ventricular Assist Device.

BACKGROUND: In patients with the HeartMate 3 (HM3, Abbott) left ventricular (LV) assist device (LVAD), outflow graft narrowing has been reported as a result of accumulation of biodebris either internal or external to the graft. This study describes the prevalence, imaging findings, and clinical outcomes associated with HM3 LVAD outflow graft narrowing. METHODS: A single-center retrospective cohort study was performed in patients who received an HM3 LVAD between November 2014 and July 2019. All patients with a computed tomographic (CT) angiogram or a CT scan with intravenous contrast sufficient to evaluate the outflow graft lumen were included. Narrowing was defined as a hypodensity of ≥3 mm. RESULTS: Of 165 HM3 LVAD recipients, 46 (28%) had qualifying imaging. Outflow graft narrowing was present in 33% (15/46). One patient had complete obstruction requiring emergency surgery, whereas 14 patients had a median hypodensity of 4.5 mm (interquartile range, 3.3-5.8 mm). The presence of outflow graft narrowing was significantly associated with a longer duration of LVAD support (588.2 ± 277.5 days vs 131.5 ± 170.9 days; P < .0001). One-year survival after identification of narrowing was 93%, with death occurring in 1 patient with complete obstruction. LV unloading (mean percent decrease in LV end-diastolic diameter at time of CT imaging vs pre-LVAD) was 16.7% vs 17.7% in patients with and without narrowing, respectively (P = .86). CONCLUSIONS: Among patients with adequate imaging, one-third have evidence of narrowing. Outflow graft narrowing secondary to biodebris was more likely to be found in HM3 LVAD recipients with longer duration of LVAD support. There was no significant difference in LV unloading between patients with and without narrowing.