Extracorporeal Membrane Oxygenation in New York State: Trends, Outcomes, and Implications for Patient Selection

Scrutinizing the Role of Venoarterial Extracorporeal Membrane Oxygenation: Has Clinical Practice Outpaced the Evidence?

The use of venoarterial extracorporeal membrane oxygenation (VA-ECMO) for temporary mechanical circulatory support in various clinical scenarios has been increasing consistently, despite the lack of sufficient evidence regarding its benefit and safety from adequately powered randomized controlled trials. Although the ARREST trial (Advanced Reperfusion Strategies for Patients with Out-of-Hospital Cardiac Arrest and Refractory Ventricular Fibrillation) and a secondary analysis of the PRAGUE OHCA trial (Prague Out-of-Hospital Cardiac Arrest) provided some evidence in favor of VA-ECMO in the setting of out-of-hospital cardiac arrest, the INCEPTION trial (Early Initiation of Extracorporeal Life Support in Refractory Out-of-Hospital Cardiac Arrest) has not found a relevant improvement of short-term mortality with extracorporeal cardiopulmonary resuscitation. In addition, the results of the recently published ECLS-SHOCK trial (Extracorporeal Life Support in Cardiogenic Shock) and ECMO-CS trial (Extracorporeal Membrane Oxygenation in the Therapy of Cardiogenic Shock) discourage the routine use of VA-ECMO in patients with infarct-related cardiogenic shock. Ongoing clinical trials (ANCHOR [Assessment of ECMO in Acute Myocardial Infarction Cardiogenic Shock, NCT04184635], REVERSE [Impella CP With VA ECMO for Cardiogenic Shock, NCT03431467], UNLOAD ECMO [Left Ventricular Unloading to Improve Outcome in Cardiogenic Shock Patients on VA-ECMO, NCT05577195], PIONEER [Hemodynamic Support With ECMO and IABP in Elective Complex High-risk PCI, NCT04045873]) may clarify the usefulness of VA-ECMO in specific patient subpopulations and the efficacy of combined mechanical circulatory support strategies. Pending further data to refine patient selection and management recommendations for VA-ECMO, it remains uncertain whether the present usage of this device improves outcomes.

The use of veno-arterial extracorporeal membrane oxygenation in the octogenarian population: A single-center experience

INTRODUCTION

Advanced age is a known risk factor for poor outcomes after veno-arterial extracorporeal membrane oxygenation (V-A ECMO) for cardiac support. The use of ECMO support in patients over the age of 80 is controversial, and sometimes its use is contraindicated. We aimed to assess the use of ECMO in octogenarian patients to determine survival and complication rates.

METHODS

A single-center, retrospective analysis was completed at a large, urban academic medical center. Patients requiring V-A ECMO support between December of 2012 and November of 2019 were included as long as the patient was at least 80 years of age at the time of cannulation. Post cardiotomy shock patients were excluded.

RESULTS

A total of 46 patients met eligibility criteria; all received V-A ECMO support. Overall, the majority of patients (71.7%; 33/46) survived to decannulation, and 43.5% (20/46) survived to discharge. Patients who were previously rescued from percutaneous interventions tend to have a better survival than other patients (p = .06). The most common complications were renal and hemorrhagic.

CONCLUSIONS

We demonstrated that advanced age alone should not disqualify patients from cannulating and supporting with V-A ECMO.

Risk stratification of patients listed for heart transplantation while supported with extracorporeal membrane oxygenation

OBJECTIVES

Extracorporeal membrane oxygenation (ECMO) is used to support patients in severe cardiogenic shock. In the absence of recovery, these patients may need to be listed for heart transplant (HT), which offers the best long-term prognosis. However, posttransplantation mortality is significantly elevated in patients who receive ECMO. The objective of the present study was to describe and risk-stratify different profiles of patients listed for HT supported by ECMO.

METHODS

Patients listed for HT in the United Network for Organ Sharing database were analyzed. The primary outcome was 1-year survival and was assessed in patients bridged to transplant with ECMO (ECMO_BTT) and patients who were previously supported on ECMO but had it removed before HT (ECMO_REMOVED).

RESULTS

Among 65,636 adult candidates listed for HT (between 2001 and 2017), 712 were supported on ECMO, 292 of whom (41%) underwent HT (ECMO_BTT, n = 202; ECMO_REMOVED, n = 90). Most of the patients with ECMO_REMOVED were transplanted with a ventricular assist device. In ECMO_BTT, recipient age (each 10-year increase), time on the waitlist (both defined as minor risk factors), need for dialysis, and need for mechanical ventilation (both defined as major risk factors) were independent predictors of mortality. ECMO_REMOVED and ECMO_BTT with no risk factors showed 1-year survival comparable to that in patients who were never supported on ECMO. Compared with patients who were never on ECMO, patients in ECMO_BTT group with minor risk factors, 1 major risk factor, and 2 major risk factors had ~2-, ~5-, and >10-fold greater 1-year mortality, respectively (P < .05).

CONCLUSIONS

The HT recipients in the ECMO_REMOVED and ECMO_BTT groups with no risk factors showed similar survival as the HT recipients who were never supported on ECMO. In the ECMO_BTT group, posttransplantation mortality increased significantly with increasing risk factors.

Mechanical Assist Device-Assisted Percutaneous Coronary Intervention: The Use of Impella Versus Extracorporeal Membrane Oxygenation as an Emerging Frontier in Revascularization in Cardiogenic Shock

The extracorporeal membrane oxygenation (ECMO) procedure aids in the provision of prolonged cardiopulmonary support, whereas the Impella device (Abiomed, Danvers, MA) is a ventricular assist device that maintains circulation by pumping blood into the aorta from the left ventricle. Blood is circulated in parallel with the heart by Impella. It draws blood straight into the aorta from the left ventricle, hence preserving the physiological flow. ECMO bypasses the left atrium and the left ventricle, and the end consequence is a non-physiological flow. In this article, we conducted a detailed analysis of various publications in the literature and examined various modalities pertaining to the use of ECMO and Impella for cardiogenic shocks, such as efficacy, clinical outcomes, cost-effectiveness, device-related complications, and limitations. The Impella completely unloads the left ventricle, thereby significantly reducing the effort of the heart. Comparatively, ECMO only stabilizes a patient with cardiogenic shock for a short stretch of time and does not lessen the efforts of the left ventricle ("unload" it). In the acute setting, both devices reduced left ventricular end-diastolic pressure and provided adequate hemodynamic support. By comparing patients on Impella to those receiving ECMO, it was found that patients on Impella were associated with better clinical results, quicker recovery, limited complications, and reduced healthcare costs; however, there is a lack of conclusive studies performed demonstrating the reduction in long-term mortality rates. Considering the effectiveness of given modalities and taking into account the various studies described in the literature, Impella has reported better clinical outcomes although more clinical trials are needed for establishing the effectiveness of these interventional approaches in revascularization in cardiogenic shock.

Impella versus extracorporeal membranous oxygenation (ECMO) for cardiogenic shock: a systematic review and meta-analysis

BACKGROUND

The use of mechanical circulatory support (MCS) in cardiogenic shock (CS) is increasing. We conducted a systematic review and meta-analysis to compare outcomes with the Impella device vs. ECMO in patients with CS.

METHODS

We searched the Medline, EMBASE, Cochrane, and Clinicaltrials.gov databases for observational studies comparing Impella to ECMO in patients with CS. Risk ratios (RRs) for categorical variables and standardized mean differences (SMDs) for continuous variables were calculated with 95% confidence intervals (CIs) using a random-effects model.

RESULTS

Twelve retrospective studies and one prospective study (Impella n=6652, ECMO n=1232) were identified. Impella use was associated with lower incidence of in-hospital mortality (RR 0.88 [95% CI 0.80-0.94], p=0.0004), stroke (RR 0.30 [0.21-0.42], p<0.00001), access-site bleeding (RR 0.50 [0.37-0.69], p<0.0001), major bleeding (RR 0.56 [0.39-0.80], p=0.002), and limb ischemia (RR 0.42 [0.27-0.65], p=0.0001). Baseline lactate levels were significantly lower in the Impella group (SMD -0.52 [-0.73- -0.31], p<0.00001). There was no significant difference in mortality at 6-12 months, MCS duration, need for MCS escalation, bridge-to-LVAD or heart transplant, and renal replacement therapy use between Impella and ECMO groups.

CONCLUSION

In patients with CS, Impella device use was associated with lower in-hospital mortality, stroke, and device-related complications than ECMO. However, patients in the ECMO group had higher baseline lactate levels.

Short-term mechanical circulatory support in elderly patients

BACKGROUND

Age over 70 years seems to confer poor prognosis for patients under mechanical circulatory support (MCS). Advanced age is usually a relative contraindication. Our objective was to assess the impact of age on survival of patients with short-term MCS.

METHODS

Retrospective analysis of ≥70-year-old patients supported with veno-arterial extracorporeal membrane oxygenation (VA-ECMO) or Impella CP® due to cardiogenic shock and other situations of hemodynamic instability in a referral hospital (elderly group), compared with younger patients (<70 years). We analyze factors associated with survival in elderly group.

RESULTS

Out of 164 short-term MCS implants from 2013 to October 2020, 45 (27.4%) correspond to ≥70-year-old patients (73.3% VA-ECMO; 26.7% Impella CP®), 80% as bridge to recovery and 15.6% for high-risk percutaneous coronary intervention (PCI). We found no significant differences in complications developed between both groups. Survivals at discharge (40% vs. 43.7%, p = 0.403) and at follow-up (median 13.6 [30] months) were similar in elderly and young patients (35.6% vs. 37.8%, log-rank p = 0.061). Predictive factors of mortality in elderly patients were peripheral artery disease (p = 0.037), higher lactate (p = 0.003) and creatinine (p = 0.035) at implant, longer cardiac arrest (p = 0.003), and worse post-implantation left ventricular ejection fraction (p = 0.003). Patients with indication of MCS for high-risk PCI had higher survival compared to other indications (p = 0.013).

CONCLUSION

Short-term MCS with VA-ECMO or Impella CP® in elderly patients may be a reasonable option in hemodynamic compromise situations as bridge to recovery or elective high-risk PCI, without a significant increase in complications or mortality. Age should not be an absolute contraindication, but careful selection of candidate patients is necessary.

Extracorporeal Life Support for Cardiac Arrest and Cardiogenic Shock

The rising incidence and recognition of cardiogenic shock has led to an increase in the use of veno-arterial extracorporeal membrane oxygenation (VA-ECMO). As clinical experience with this therapy has increased, there has also been a rapid growth in the body of observational and randomized data describing the clinical and logistical considerations required to institute a VA-ECMO program with successful clinical outcomes. The aim of this review is to summarize this contemporary data in the context of four key themes that pertain to VA-ECMO programs: the principles of patient selection; basic hemodynamic and technical principles underlying VA-ECMO; contraindications to VA-ECMO therapy; and common complications and intensive care considerations that are encountered in the setting of VA-ECMO therapy.

Key Factors in Decision Making for ECLS: A Binational Factorial Survey

Background

Extracorporeal life support (ECLS) provides support to patients with cardiopulmonary failure refractory to conventional therapy. While ECLS is potentially life-saving, it is associated with severe complications; decision making to initiate ECLS must, therefore, carefully consider which patients ECLS potentially benefits despite its consequences.

Objective

To answer 2 questions: First, which medically relevant patient factors influence decisions to initiate ECLS? Second, what are factors relevant to decisions to withdraw a running ECLS treatment?

Methods

We conducted a factorial survey among 420 physicians from 111 hospitals in Switzerland and Germany. The study included 2 scenarios: 1 explored willingness to initiate ECLS, and 1 explored willingness to withdraw a running ECLS treatment. Each participant responded to 5 different vignettes for each scenario. Vignettes were analyzed using mixed-effects regression models with random intercepts.

Results

Factors in the vignettes such as patients’ age, treatment costs, therapeutic goal, comorbidities, and neurological outcome significantly influenced the decision to initiate ECLS. When it came to the decision to withdraw ECLS, patients’ age, days on ECLS, criteria for discontinuation, condition of the patient, comorbidities, and neurological outcome were significant factors. In both scenarios, patients’ age and neurological outcome were the most influential factors.

Conclusions

This study provided insights into physicians’ decision making processes about ECLS initiation and withdrawal. Patients’ age and neurological status were the strongest factors influencing decisions regarding initiation of ECLS as well as for ECLS withdrawal. The findings may contribute to a more refined understanding of complex decision making for ECLS.

Outcomes of Venoarterial Extracorporeal Membrane Oxygenation for Cardiac Arrest in Adult Patients in the United States

Background

Factors associated with poor prognosis following receipt of extracorporeal membrane oxygenation (ECMO) in adults with cardiac arrest remain unclear. We aimed to identify predictors of mortality in adults with cardiac arrest receiving ECMO in a nationally representative sample.

Methods and Results

The US Healthcare Cost and Utilization Project's National Inpatient Sample was used to identify 782 adults hospitalized with cardiac arrest who received ECMO between 2006 and 2014. The primary outcome of interest was all‐cause in‐hospital mortality. Factors associated with mortality were analyzed using multivariable logistic regression. The overall in‐hospital mortality rate was 60.4% (n=472). Patients who died were older and more often men, of non‐White race, and with lower household income than those surviving to discharge. In the risk‐adjusted analysis, independent predictors of mortality included older age, male sex, lower annual income, absence of ventricular arrhythmia, absence of percutaneous coronary intervention, and presence of therapeutic hypothermia.

Conclusions

Demographic and therapeutic factors are independently associated with mortality in patients with cardiac arrest receiving ECMO. Identification of which patients with cardiac arrest may receive the utmost benefit from ECMO may aid with decision‐making regarding its implementation. Larger‐scale studies are warranted to assess the appropriate candidates for ECMO in cardiac arrest.

SEDAR/SECCE ECMO management consensus document

ECMO is an extracorporeal cardiorespiratory support system whose use has been increased in the last decade. Respiratory failure, postcardiotomy shock, and lung or heart primary graft failure may require the use of cardiorespiratory mechanical assistance. In this scenario perioperative medical and surgical management is crucial. Despite the evolution of technology in the area of extracorporeal support, morbidity and mortality of these patients continues to be high, and therefore the indication as well as the ECMO removal should be established within a multidisciplinary team with expertise in the area. This consensus document aims to unify medical knowledge and provides recommendations based on both the recent bibliography and the main national ECMO implantation centres experience with the goal of improving comprehensive patient care.

Comparison of in-hospital outcomes of patients with vs. without ischaemic cardiomyopathy undergoing veno-arterial-extracorporeal membrane oxygenation

AIMS

This study aimed to investigate differences in baseline and treatment characteristics, and in-hospital mortality according to the aetiologies of cardiogenic shock in patients undergoing veno-arterial-extracorporeal membrane oxygenation (VA-ECMO).

METHODS AND RESULTS

The RESCUE registry is a multicentre, observational cohort that includes 1247 patients with cardiogenic shock from 12 centres. A total of 496 patients requiring VA-ECMO were finally selected, and the study population was stratified by cardiogenic shock aetiology [ischaemic cardiomyopathy (ICM, n = 342) and non-ICM (NICM, n = 154)]. The primary outcome of interest was in-hospital mortality. Sensitivity analyses including propensity-score matching adjustments were performed. Mean age of the entire population was 61.8 ± 14.2, and 30.8% were women. There were significant differences in baseline characteristics; notable differences included the older age of patients with ICM (65.1 ± 13.7 vs. 58.2 ± 13.8, P < 0.001), preponderance of males [258 (75.4%) vs. 85 (55.2%), P < 0.001], and higher prevalence of diabetes mellitus [140 (40.9%) vs. 39 (25.3%), P = 0.001] compared with patients in the NICM aetiology group. Patients with ischaemic cardiogenic shock were more likely to have longer shock duration before VA-ECMO implantation (518.7 ± 941.4 min vs. 292.4 ± 707.8 min, P = 0.003) and were less likely to undergo distal limb perfusion than those with NICM [108 (31.6%) vs. 79 (51.3%), P < 0.001]. In-hospital mortality in the overall cohort was 52.2%; patients with ICM had a higher unadjusted risk of in-hospital mortality [203 (59.4%) vs. 56 (36.4%); unadjusted hazard ratio, 2.295; 95% confidence interval, 1.698-3.100; P < 0.001]. There were no significant differences in the primary outcome between the two aetiologies following propensity-score matching multiple adjustments (adjusted hazard ratio, 1.265; 95% confidence interval, 0.840-1.906; P = 0.260).

CONCLUSIONS

Results of the current study indicated among patients with cardiogenic shock undergoing VA-ECMO, ischaemic aetiology does not seem to impact in-hospital mortality. These findings underline that early initiation and appropriate treatment strategies of VA-ECMO for patients with ICM shock are required.

Temporary Mechanical Circulatory Support as a Bridge to Heart Transplant or Durable Left Ventricular Assist Device

Advanced heart failure refractory to medical therapy can result in patients presenting with progressively worsening hypoperfusion and cardiogenic shock. Temporary mechanical circulatory support is often necessary as a bridge to heart transplant or durable ventricular assist devices. These devices increase cardiac output. Several options are available for left ventricular support. With the exception of venoarterial extracorporeal membrane oxygenation, all other devices decrease left ventricular end-diastolic pressure. The choice of device should be driven by patient needs and the treating teams comfort. Timely identification of cardiogenic shock and use of shock teams are potential strategies that can help improve survival.

Contemporary Use of Venoarterial Extracorporeal Membrane Oxygenation: Insights from the Multicenter RESCUE Registry

BACKGROUND

Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is increasingly used as a life-saving therapy for patients with cardiovascular collapse, but identifying patients unlikely to benefit remains a challenge.

METHODS AND RESULTS

We created the RESCUE registry, a retrospective, observational registry of adult patients treated with VA-ECMO between January 2007 and June 2017 at 3 high-volume centers (Columbia University, Duke University, and Washington University) to describe short-term patient outcomes. In 723 patients treated with VA-ECMO, the most common indications for deployment were postcardiotomy shock (31%), cardiomyopathy (including acute heart failure) (26%), and myocardial infarction (17%). Patients frequently suffered in-hospital complications, including acute renal dysfunction (45%), major bleeding (41%), and infection (33%). Only 40% of patients (n = 290) survived to discharge, with a minority receiving durable cardiac support (left ventricular assist device [n = 48] or heart transplantation [n = 7]). Multivariable regression analysis identified risk factors for mortality on ECMO as older age (odds ratio [OR], 1.26; 95% confidence interval [CI], 1.12-1.42) and female sex (OR, 1.44; 95% CI, 1.02-2.02) and risk factors for mortality after decannulation as higher body mass index (OR 1.17; 95% CI, 1.01-1.35) and major bleeding while on ECMO support (OR, 1.92; 95% CI, 1.23-2.99).

CONCLUSIONS

Despite contemporary care at high-volume centers, patients treated with VA-ECMO continue to have significant in-hospital morbidity and mortality. The optimization of outcomes will require refinements in patient selection and improvement of care delivery.

Outcomes of Hospitalizations for Cardiogenic Shock at Left Ventricular Assist Device Versus Non-Left Ventricular Assist Device Centers

Background Cardiogenic shock (CS) is a complex syndrome associated with high morbidity and mortality. In recent years, many US hospitals have formed multidisciplinary shock teams capable of rapid diagnosis and triage. Because of preexisting collaborative systems of care, hospitals with left ventricular assist device (LVAD) programs may also represent "centers of excellence" for CS care. However, the outcomes of patients with CS at LVAD centers have not been previously evaluated. Methods and Results Patients with CS were identified in the 2012 to 2014 National Inpatient Sample. Clinical characteristics, revascularization rates, and use of mechanical circulatory support were analyzed in LVAD versus non-LVAD centers. The association between hospital type and in-hospital mortality was examined using multivariable logistic regression models. Of 272 075 hospitalizations, 26.0% were in LVAD centers. CS attributable to causes other than acute myocardial infarction represented most cases. In-hospital mortality was lower in LVAD centers (38.9% versus 43.3%; P<0.001). In multivariable analysis, the odds of mortality remained significantly lower for hospitalizations in LVAD centers (odds ratio, 0.89; P<0.001). In patients with CS secondary to acute myocardial infarction, revascularization rates were similar between LVAD and non-LVAD centers. The use of intra-aortic balloon pump (18.7% versus 18.8%) and Impella/TandemHeart (2.6% versus 1.9%) was similar between hospital types, whereas extracorporeal membrane oxygenation was used more frequently in LVAD centers (4.3% versus 0.2%; P<0.001). Conclusions Risk-adjusted mortality was lower in patients with CS who were hospitalized at LVAD centers. These centers likely represent specialized, shock team capable institutions across the country that may be best suited to manage patients with CS.

The science of safety: complications associated with the use of mechanical circulatory support in cardiogenic shock and best practices to maximize safety

Acute mechanical circulatory support (MCS) devices are widely used in cardiogenic shock (CS) despite a lack of high-quality clinical evidence to guide their use. Multiple devices exist across a spectrum from modest to complete support, and each is associated with unique risks. In this review, we summarize existing data on complications associated with the three most widely used acute MCS platforms: the intra-aortic balloon pump (IABP), Impella systems, and veno-arterial extracorporeal membrane oxygenation (VA-ECMO). We review evidence from available randomized trials and highlight challenges comparing complication rates from case series and comparative observational studies where a lack of granular data precludes appropriate matching of patients by CS severity. We further offer a series of best practices to help shock practitioners minimize the risk of MCS-associated complications and ensure the best possible outcomes for patients.

Favorable Outcomes of a Direct Heart Transplantation Strategy in Selected Patients on Extracorporeal Membrane Oxygenation Support

OBJECTIVES

Heart transplantation in patients supported by venoarterial extracorporeal membrane oxygenation has been associated with poor prognosis. A specific protocol for extracorporeal membrane oxygenation management encompassing patient selection, implantation strategy, and preoperative and perioperative treatment is applied at our institution. Our aim was to compare posttransplant outcomes of patients supported or not by extracorporeal membrane oxygenation at the time of heart transplantation.

DESIGN

A large observational single-center retrospective study was conducted. The primary endpoint was overall survival after heart transplantation. Secondary endpoints included death-censored rejection-free survival and the frequency of extracorporeal membrane oxygenation-related complications.

SETTING

One heart transplantation and extracorporeal membrane oxygenation high-volume center.

PATIENTS

All consecutive patients over 18 years old with a first noncombined heart transplantation performed between 2012 and 2016 were included.

INTERVENTIONS

None (retrospective observational study).

MEASUREMENTS AND MAIN RESULTS

Among the 415 transplanted patients, 118 (28.4%) were on extracorporeal membrane oxygenation at the time of transplantation (peripheral, 94%; intrathoracic, 6%). Median time on extracorporeal membrane oxygenation before heart transplantation was 9 days (interquartile range, 5-15 d) and median follow-up post heart transplantation was 20.7 months. Posttransplant survival did not differ significantly between the two groups (1-yr survival = 85.5% and 80.7% in extracorporeal membrane oxygenation vs nonextracorporeal membrane oxygenation patients; hazard ratio, 0.69; 95% CI, 0.43-1.11; p = 0.12, respectively). Donor age, body mass index, creatinine clearance, and ischemic time were independently associated with overall mortality, but not extracorporeal membrane oxygenation at the time of heart transplantation. Rejection-free survival also did not significantly differ between groups (hazard ratio, 0.85; 95% CI, 0.60-1.23; p = 0.39). Local wound infection was the most frequent complication after extracorporeal membrane oxygenation (37% of patients).

CONCLUSIONS

With the implementation of a specific protocol, patients bridged to heart transplantation on extracorporeal membrane oxygenation had similar survival compared with those not supported by extracorporeal membrane oxygenation.

Cost-utility of venoarterial extracorporeal membrane oxygenation in cardiogenic shock and cardiac arrest

BACKGROUND

The use of venoarterial extracorporeal membrane oxygenation in cardiogenic shock keeps increasing, but its cost-utility is unknown.

METHODS

We studied retrospectively the cost-utility of venoarterial extracorporeal membrane oxygenation in a five-year cohort of consequent patients treated due to refractory cardiogenic shock or cardiac arrest in a transplant centre in 2013-2017. In our centre, venoarterial extracorporeal membrane oxygenation is considered for all cardiogenic shock patients potentially eligible for heart transplantation, and for selected postcardiotomy patients. We assessed the costs of the index hospitalization and of the one-year hospital costs, and the patients' health-related quality of life (response rate 71.7%). Based on the data and the population-based life expectancies, we calculated the amount and the costs of quality-adjusted life years gained both without discount and with an annual discount of 3.5%.

RESULTS

The cohort included 102 patients (78 cardiogenic shock; 24 cardiac arrest) of whom 67 (65.7%) survived to discharge and 66 (64.7%) to one year. The effective costs per one hospital survivor were 242,303€. Median in-hospital costs of the index hospitalization per patient were 129,967€ (interquartile range 150,340€). Mean predicted number of quality-adjusted life years gained by the treatment was 20.9 (standard deviation 9.7) without discount, and the median cost per quality-adjusted life year was 7474€ (interquartile range 10,973€). With the annual discount of 3.5%, 13.0 (standard deviation 4.8) quality-adjusted life years were gained with the cost of 12,642€ per quality-adjusted life year (interquartile range 15,059€).

CONCLUSIONS

We found the use of venoarterial extracorporeal membrane oxygenation in refractory cardiogenic shock and cardiac arrest justified from the cost-utility point of view in a transplant centre setting.

Extracorporeal Membrane Oxygenation Use in Cardiogenic Shock: Impact of Age on In-Hospital Mortality, Length of Stay, and Costs

OBJECTIVES

Increasing age is a well-recognized risk factor for in-hospital mortality in patients receiving extracorporeal membrane oxygenation for cardiogenic shock, but the shape of this relationship is unknown. In addition, the impact of age on hospital length of stay, patterns of patient disposition, and costs has been incompletely characterized.

DESIGN

Retrospective analysis of the National Inpatient Sample.

SETTING

U.S. nonfederal hospitals, years 2004-2016.

PATIENTS

Adults with cardiogenic shock treated with extracorporeal membrane oxygenation (3,094; weighted national estimate: 15,415).

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The mean age of extracorporeal membrane oxygenation recipients was 54.8 ± 15.4 years (range, 18-90 yr). Crude in-hospital mortality was 57.7%. Median time-to-death was 8 days (interquartile range, 3-17 d). A linear relationship between age and in-hospital mortality was observed with a 14% increase in the adjusted odds of in-hospital mortality for every 10-year increase in age (adjusted odds ratio, 1.14; 95% CI, 1.08-1.21; p < 0.0001). Thirty-four percent of patients were discharged alive at a median time of 30 days (interquartile range, 19-48 d). The median length of stay and total hospitalization costs were 14 days (interquartile range, [5-29 d]) and $134,573 ($71,782-$239,439), respectively, both of which differed significantly by age group (length of stay range from 17 d [18-49 yr] to 9 d [80-90 yr]; p < 0.0001 and cost range $147,548 [18-49 yr] to $105,350 [80-90 yr]; p < 0.0001).

CONCLUSIONS

Age is linearly associated with increasing in-hospital mortality in individuals receiving extracorporeal membrane oxygenation for cardiogenic shock without evidence of a threshold effect. Median time-to-death is approximately 1 week. One third of patients are discharged from the hospital alive, but the median time-to-discharge is 1 month. Median length of stay ranges from 9 to 17 days depending on age. Hospitalization costs exceed $100,000 in all age groups.

Numerical analysis of aortic hemodynamics under the support of venoarterial extracorporeal membrane oxygenation and intra-aortic balloon pump

BACKGROUND AND OBJECTIVE

A gap still exists in the hemodynamic effect of intra-aortic balloon pump (IABP), venoarterial extracorporeal membrane oxygenation (VA-ECMO), and VA-ECMO plus IABP on the blood perfusion of the coronary artery, brain, and lower limb; the relation between heart flow and ECMO flow; and the wall stress of vessels.

METHODS

A finite-element model of the aorta, ECMO, and IABP was proposed to calculate the mechanical response via fluid-structure interaction. Heart failure (HF), IABP, ECMO, and ECMO plus IABP were utilized to study the effect of support models.

RESULTS

For the pressure curve, VA-ECMO weakened the dicrotic notch of pressure compared with HF and the pulsatile index (0.494 vs. 0.706 vs. 0.471 vs. 0.613). IABP, ECMO, and ECMO plus IABP increased the perfusion of the coronary, brain, and renal artery compared with HF. However, ECMO and ECMO plus IABP clearly reduced the blood flow of the left arteria femoralis compared to that of the right arteria femoralis (ECMO: 194.04 vs. 730.80 mL/min; ECMO plus IABP: 342.15 vs. 947.22 mL/min). In addition, the flow of ECMO accessed the renal artery more than the left ventricular flow. Greater ventricular flow perfused to the renal artery at a diastolic period for ECMO plus IABP, especially at the time points of 2.192 s and 2.304 s. Compared to the velocity distribution with ECMO, the flow of the right arteria femoralis was increased in the process of IABP-on. According to these four cases, the stress of the vascular wall was increased for ECMO support at the systolic period. The peak wall stress of ECMO is increased by 20% at 1.68 s.

CONCLUSIONS

ECMO plus IABP is more conducive to the blood supply than other cases from the result of numerical simulation. The location of blood intersection was generated in the region of the renal artery, which is estimated carefully.

Impact of age on outcomes of patients assisted by veno-arterial or veno-venous extra-corporeal membrane oxygenation: 403 patients between 2005 and 2015

INTRODUCTION

To assess the impact of age on early outcomes and mortality in veno-arterial extra-corporeal membrane oxygenation and veno-venous extra-corporeal membrane oxygenation recipients, and to investigate predictors of mortality.

METHODS

Single-center retrospective study on prospectively collected data including all patients treated by veno-venous extra-corporeal membrane oxygenation and veno-arterial extra-corporeal membrane oxygenation (January 2005-July 2015). Outcomes were compared among two subgroups: aged less than 65 years (Group 1) versus more than 65 years (Group 2) and by type of support (veno-arterial extra-corporeal membrane oxygenation or veno-venous extra-corporeal membrane oxygenation).

RESULTS

Among 403 patients, 20.3% were treated by veno-venous extra-corporeal membrane oxygenation and 79.7% by veno-arterial extra-corporeal membrane oxygenation. Veno-arterial extra-corporeal membrane oxygenation group: 76.6% were included in Group 1 and were more severe (pH 7.30 ± 0.19 vs. 7.35 ± 0.13 in Group 2, p = 0.003; lactates 7.5 ± 5.6 mmol/L vs. 5.8 ± 4.5 mmol/L in Group 2, p = 0.003). Weaning rate was higher in Group 1 (63.8% vs. 45.3%, p = 0.0043). The 30-day survival was higher in Group 1 (52.0% vs. 25.3%, p < 0.001). Univariate analysis identified higher Simplified Acute Physiology Score II (p = 0.02) and noradrenaline (p = 0.04) to be associated with mortality. Veno-venous extra-corporeal membrane oxygenation group: 80.5% were in Group 1. Mean PaO₂ was 73.5 ± 42.9 mm Hg versus 100.8 ± 80.3 mm Hg (p = 0.24); FiO₂ 90.1% ± 18% versus 89.4% ± 16.4% (p = 0.89); and 30-day survival 56.1% versus 25.0% (p = 0.048).

CONCLUSION

Patients older than 65 years have higher mortality after veno-arterial extra-corporeal membrane oxygenation or veno-venous extra-corporeal membrane oxygenation. This therapeutic strategy is feasible in the elderly, but comorbidities and clinical presentation have a major impact on prognosis and need to be seriously considered to avoid futile treatment.

Hemolysis and Nonhemorrhagic Stroke During Venoarterial Extracorporeal Membrane Oxygenation

BACKGROUND

Hemolysis, even at low levels, activates platelets to create a prothrombotic state and is common during mechanical circulatory support. We examined the association of low-level hemolysis (LLH) and nonhemorrhagic stroke during venoarterial extracorporeal membrane oxygenation (VA ECMO) support.

METHODS

A single-center retrospective review of all adult patients placed on VA ECMO from January 2012 to September 2017 was conducted. To determine the association between LLH and nonhemorrhagic stroke, patients were categorized as those with and without LLH. LLH was defined by 48-hour plasma free hemoglobin (PFHb) of 11 to 50 mg/dL after VA ECMO implantation.

RESULTS

Of 201 patients who underwent VA ECMO placement, 150 (75%) met inclusion criteria and comprised the study population. They were 55 ± 14 years of age and 50 (33%) were women. Sixty-two (41%) patients had LLH. Patients with LLH had a higher likelihood of incident nonhemorrhagic stroke during VA ECMO support (20 [32%] versus 4 [5%]; adjusted hazard ratio [HR], 7.6; 95% confidence interval [CI], 2.2 to 25.9; p = 0.001). The severity of LLH was associated with an incrementally higher likelihood of a nonhemorrhagic stroke (PFHb 26 to 50 mg/dL: HR, 11.3; 95% CI, 3.6 to 35.1; p = 0.001; PFHb 11 to 25 mg/dL: HR, 4.4; 95% CI, 1.36 to 14.85; p = 0.014) in comparison with no LLH. Those with LLH had a 2-fold greater increase in mean platelet volume after VA ECMO placement (0.98 ± 1.1 fL versus 0.49 ± 0.96 fL; p = 0.03). Patients with a nonhemorrhagic stroke had a higher operative mortality (20 [83%] versus 57 [45%]; adjusted HR, 3.1; 95% CI, 1.8 to 5.3; p < 0.001).

CONCLUSIONS

Hemolysis at low levels during VA ECMO support is associated with subsequent nonhemorrhagic stroke.

Venoarterial extracorporeal membrane oxygenation: A systematic review of selection criteria, outcome measures and definitions of complications

PURPOSE

The purpose of this study was to systematically investigate the reporting of selection criteria and outcome measures, and to examine definitions of complications used in venoarterial extracorporeal membrane oxygenation studies (V-A ECMO).

MATERIALS AND METHODS

Medline, EMBASE and the Cochrane central register were searched for V-A ECMO studies from January 2005 to July 2017. Studies with ≤99 patients or without patient centered outcomes were excluded. Two reviewers independently assessed search results and undertook data extraction.

RESULTS

Forty-six studies met the inclusion criteria, and all were retrospective, observational studies. Inconsistent reporting of selection criteria, ECMO management and outcome measures was common. In-hospital mortality was the most common primary outcome (41% of studies), followed by 30-day mortality (11%). Bleeding was the most frequent complication reported, most commonly defined as "bleeding requiring transfusion" (median ≥ 2 Units/day). Significant variation in reporting and definitions was also evident for vascular, neurological renal and infectious complications.

CONCLUSION

This systematic review provides clinicians with the most commonly reported selection criteria, outcome measures and complications used in ECMO practice. However non-standardized definitions and inconsistent reporting limits their ability to inform practice. New consensus driven definitions of complications and patient centred outcomes are urgently needed.

Venoarterial Extracorporeal Membrane Oxygenation in Cardiogenic Shock

Venoarterial extracorporeal membrane oxygenation has emerged as a viable treatment for patients in cardiogenic shock with biventricular failure and pulmonary dysfunction. Advances in pump and oxygenator technology, cannulation strategies, patient selection and management, and durable mechanical circulatory support have contributed to expanded utilization of this technology. However, challenges remain that require investigation to improve outcomes.