The use of venoarterial extracorporeal membrane oxygenation in cardiogenic shock: a narrative review.

Aims: Cardiogenic shock (CS) develops in up to 10% of patients with acute myocardial infarction (AMI) and carries a 50% risk of mortality. Despite the paucity of evidence regarding its benefits, venoarterial extracorporeal membrane oxygenation (VA-ECMO) is increasingly used in clinical practice in patients with AMI in CS (AMI-CS). This review aims to provide an in-depth description of the four available randomized controlled trials to date designed to evaluate the benefit of VA-ECMO in patients with AMI-CS. Methods and results: The literature search was conducted on PubMed, Google Scholar, and clinicaltrials.gov to identify the four relevant randomized control trials from years of inception to October 2023. Despite differences in patient selection, nuances in trial conduction, and variability in trial endpoints, all four trials (ECLS-SHOCK I, ECMO-CS, EUROSHOCK, and ECLS-SHOCK) failed to demonstrate a mortality benefit with the use of VA-ECMO in AMI-CS, with high rates of device-related complications. However, the outcome of these trials is nuanced by the limitations of each study that include small sample sizes, challenging patient selection, and high cross-over rates to the intervention group, and lack of use of left ventricular unloading strategies. Conclusion: The presented literature of VA-ECMO in CS does not support its routine use in clinical practice. We have yet to identify which subset of patients would benefit most from this intervention. This review emphasizes the need for designing adequately powered trials to properly assess the role of VA-ECMO in AMI-CS, in order to build evidence for best practices.

The Ramus Intermedius: A Bridge to Survival in the Setting of Triple-Vessel Total Occlusion.

Coronary artery disease continues to remain the leading cause of mortality worldwide. Coronary blood supply is provided through the right and left main coronary arteries. The left main coronary artery (LMCA) in turn gives rise to the left anterior descending (LAD) and left circumflex (LCX) arteries. In some cases, LMCA may trifurcate into the ramus intermedius (RI) in addition to the LAD and LCX arteries. Atherosclerotic plaque formation and rupture with subsequent clot formation and occlusion of coronary arteries are the underlying mechanisms of myocardial infarction. Though the clinical implications of the presence of ramus intermedius (RI) are controversial some data suggest that the RI is associated with an increased risk of atherosclerotic plaque formation in the LMCA and the proximal LAD. Conversely, it has been proposed that the RI provides an additional collateral source of blood supply to the myocardium and may potentially contribute to improved survival. Case reports tout the benefits of RI, specifically in the setting of multivessel coronary artery occlusions. Whether it increases the risk of atherosclerotic plaque formation or whether it is protective has yet to be determined. We present a case of a 58-year-old male who presented with acute coronary syndrome and cardiogenic shock due to total ostial occlusion of LAD. The patient had also chronic total occlusions of the right coronary artery and LCX but a patent RI, which was the only source of blood supply to the myocardium and practically determined the patient's survival. Additionally, we performed a literature review to identify similar cases, to support RI's potentially protective role in enhancing survival.

Navigating the Storm: Myxedema Coma-Induced Cardiomyopathy Culminating in Refractory Cardiogenic Shock.

Myxedema coma is a rare and life-threatening consequence of severe hypothyroidism, often precipitated by physiologic stressors. While cardiac manifestations are common, they are typically reversible with prompt treatment. Here, we report a case of a 23-year-old male with untreated hypothyroidism who presented with myxedema coma-induced cardiomyopathy leading to refractory cardiogenic shock requiring veno-arterial extracorporeal membrane oxygenation (VA-ECMO) and, ultimately, orthotopic heart transplantation (OHT). Our case highlights a rare occurrence of refractory shock necessitating mechanical support as a bridge to a cardiac transplant. We emphasize early recognition, aggressive management, and a low threshold to escalate care to mitigate the high mortality associated with myxedema coma.

Factors Influencing Successful Weaning From Venoarterial Extracorporeal Membrane Oxygenation: A Systematic Review.

With advancements in extracorporeal life support (ECLS) technologies, venoarterial extracorporeal membrane oxygenation (VA-ECMO) has emerged as a crucial cardiopulmonary support mechanism. This review explores the significance of VA-ECMO system configuration, cannulation strategies, and timing of initiation. Through an analysis of medication management strategies, complication management, and comprehensive preweaning assessments, it aims to establish a multidimensional evaluation framework to assist clinicians in making informed decisions regarding weaning from VA-ECMO, thereby ensuring the safe and effective transition of patients.

Successful prehospital ECMO in drowning resuscitation after prolonged submersion.

An 18-year-old drowning victim was successfully resuscitated using prehospital veno-arterial extracorporeal membrane oxygenation (VA-ECMO). Despite 24 min of submersion in water with a surface temperature of 15 °C, the patient was cannulated on-scene and transported to a trauma center. After ICU admission on VA-ECMO, he was decannulated and extubated by day 5. He was transferred to a peripheral hospital on day 6 and discharged home after 3.5 weeks with favorable neurological outcome of a Cerebral Performance Categories (CPC) score of 1 out of 5. This case underscores the potential of prehospital ECMO in drowning cases within a well-equipped emergency response system.

Single center outcomes after temporary mechanical circulatory assist device prior to Heartmate 3 implantation - a retrospective cohort study.

Objectives. Temporary mechanical circulatory support (TMCS) has become a component in the therapeutic strategy for treatment of cardiogenic shock as a bridge-to-decision. TMCS can facilitate recovery of cardiopulmonary function, end-organ function, and potentially reduce the surgical risk of left ventricular assist device (LVAD) implantation. Despite the improvements of hemodynamics and end-organ function, post-LVAD operative morbidity might be increased in these high-risk patients. The aim of the study was to compare outcomes after Heartmate 3 (HM3) implantation in patients with and without TMCS prior to HM3 implant. Methods. In this retrospective cohort study of all HM3 patients in the period between November 2015 and October 2021, patients with and without prior TMCS were compared. Patients' demographics, baseline clinical characteristics, laboratory tests, intraoperative variables, postoperative outcomes, and adverse events were collected from patient records. Results. The TMCS group showed an improvement in hemodynamics prior to LVAD implantation. Median TMCS duration was 19.5 (14-26) days. However, the TMCS group were more coagulopathic, had more wound infections, neurological complications, and more patients were on dialysis compared with patient without TMCS prior to HM3 implantation. Survival four years after HM3 implantation was 80 and 82% in the TMCS (N = 22) and non-TMCS group (N = 41), respectively. Conclusion. Patients on TMCS had an acceptable short and long-term survival and comparable to patients receiving HM3 without prior TMCS. However, they had a more complicated postoperative course.

Left ventricular unloading via percutaneous assist device during extracorporeal membrane oxygenation in acute myocardial infarction and cardiac arrest.

INTRODUCTION: A feared complication of an acute myocardial infarction (AMI) is cardiac arrest (CA). Even if return of spontaneous circulation is achieved, cardiogenic shock (CS) is common. Venoarterial extracorporeal membrane oxygenation (VA-ECMO) supports patients with CS and is often used in conjunction with an Impella device (2.5 and CP) to off-load the left ventricle, although limited evidence supports this approach. METHODS: The goal of this study was to determine whether a mortality difference was observed in VA-ECMO alone versus VA-ECMO with Impella (ECPELLA) in patients with CS from AMI and CA. A retrospective chart review of 50 patients with AMI-CS and CA and were supported with VA-ECMO (n = 34) or ECPELLA (n = 16) was performed. The primary outcome was all-cause mortality at 6-months from VA-ECMO or Impella implantation. Secondary outcomes included in-hospital mortality and complication rates between both cohorts and intensive care unit data. RESULTS: Baseline characteristics were similar, except patients with ST-elevation myocardial infarction were more likely to be in the VA-ECMO group (p = 0.044). The ECPELLA cohort had significantly worse survival after VA-ECMO (SAVE) score (p = 0.032). Six-month all-cause mortality was not significantly different between the cohorts, even when adjusting for SAVE score. Secondary outcomes were notable for an increased rate of minor complications without an increased rate of major complications in the ECPELLA group. CONCLUSIONS: Randomized trials are needed to determine if a mortality difference exists between VA-ECMO and ECPELLA platforms in patients with AMI complicated by CA and CS.

Cardiovascular Collapse Requiring Veno-Arterial Extracorporeal Membrane Oxygenation and Lidocaine: A Case of Massive Bupropion Overdose.

Bupropion is an antidepressant used in the treatment of major depressive disorder, seasonal affective disorder, nicotine addiction, and weight loss. It primarily functions via norepinephrine and dopamine reuptake inhibition. At toxic doses, bupropion can elicit seizures, as well as precipitate corrected QT interval (QTc) and QRS prolongation. We describe a case of an 18-year-old female who reportedly ingested 28 grams of extended-release bupropion, a dose much higher than in previously reported cases. Toxic ingestion precipitated status epilepticus, prolonged QTc, widened QRS, pulseless ventricular tachycardia (pVT), and subsequent cardiovascular collapse necessitating veno-arterial extracorporeal membrane oxygenation (ECMO) and Impella support. Historically, the cardiotoxic effects of bupropion toxicity have largely been treated with supportive care, sometimes requiring ECMO. This patient's course was complicated by a widening QRS despite aggressive bicarbonate therapy and recurrent pVT, which was ultimately aborted with lidocaine. Neurological prognostication was further complicated by a lack of brainstem reflexes on the exam. With maximal supportive care, the patient was liberated from Impella, ECMO, and the ventilator by hospital day seven. At discharge, she was neurologically intact with full recovery of cardiac function. This case emphasizes the need for early consideration of transfer to an ECMO center in the setting of a bupropion overdose and offers a potentially effective treatment option for bupropion-induced ventricular arrhythmia.

Bilateral orthotopic lung transplant via a clamshell thoracosternotomy from a donor with extended cold static lung preservation.

In this video tutorial, we present a comprehensive step-by-step operative technique for a bilateral orthotopic lung transplant using a bilateral transverse thoracosternotomy in a patient with idiopathic pulmonary fibrosis lung disease. The donor lungs were exposed to extended cold static ischaemic storage at 10° C for the semi-elective operation.

Invisible Active Bleeding Due to the Watershed Phenomenon.

A case is presented of an 83-year-old female patient with a strong suspicion of active bleeding, but no diagnostic contrast blush could be seen on the original computed tomography (CT) scan. Teaching point: When performing CT angiography in veno-arterial extracorporeal membrane oxygenation (VA-ECMO), it is important to understand the altered haemodynamics, as flow-related artefacts such as the vascular watershed phenomenon can obscure bleeding.

Cardiac Extracorporeal Membrane Oxygenation in Community Cardiac Surgery Program: Are the Results Comparable?

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) outcomes in small centers are commonly considered less favorable than in large-volume centers. New ECMO protocols and procedures were established in our regional community hospital system as part of a cardiogenic shock initiative. This retrospective study aims to evaluate the outcomes of veno-arterial extracorporeal membrane oxygenation (VA ECMO) and extracorporeal cardiopulmonary resuscitation (ECPR) in a community hospital system with cardiac surgery capability and assess whether protocol optimization and cannulation standards result in comparable outcomes to larger centers whether the outcomes of this new ECMO program at the community hospital setting were comparable to the United States averages. METHODS: Our regional system comprises five hospitals with 1500 beds covering southwestern New Jersey, with only one of these hospitals having cardiac surgery and ECMO capability. In May 2021, the new ECMO program was initiated. Patients were screened by a multidisciplinary call, cannulated by our ECMO team, and subsequently treated by the designated team. We reviewed our cardiac ECMO outcomes over two years, from May 2021 to April 2023, in patients who required ECMO due to cardiogenic shock or as a part of extracorporeal cardiopulmonary resuscitation (ECPR). RESULTS: A total of 60 patients underwent cardiac ECMO, and all were VA ECMO, including 18 (30%) patients who required ECPR for cardiac arrest. The overall survival rate for our cardiac ECMO program turned out to be 48% (29/60), with 50% (22/42) in VA ECMO excluding ECPR and 39% (7/18) in the ECPR group. The hospital survival rate for the VA ECMO and ECPR groups was 36% (15/42) and 28% (5/18), respectively. The ELSO-reported national average for hospital survival is 48% for VA ECMO and 30% for ECPR. Considering these benchmarks, the hospital survival rate of our program did not significantly lag behind the national average. CONCLUSIONS: With protocol, cannulation standards, and ECMO management optimized, the VA ECMO results of a community hospital system with cardiac surgery capability were not inferior to those of larger centers.

Evaluating the efficacy and safety of temporary mechanical circulatory support devices in acute cardiogenic shock: A subgroup-specific systematic review.

OBJECTIVE: This systematic review aims to assess the comparative effectiveness and safety of temporary mechanical circulatory support (MCS) devices in various subgroups of patients with acute cardiogenic shock, providing insights for personalized clinical decision-making. METHODS: We conducted a comprehensive search across major databases to identify studies that reported on the use of temporary MCS devices like TandemHeart, Impella, and VA-ECMO in acute cardiogenic shock. Special attention was given to subgroup analyses based on etiologies of shock, patient demographics, and comorbid conditions. RESULTS: Our analysis revealed that while devices like TandemHeart and Impella offer significant hemodynamic support, their effectiveness and safety profiles vary across different patient subgroups. VA-ECMO demonstrated the highest flow rates and potential for mortality benefits but requires careful management due to associated risks. The lack of randomized controlled trials in specific patient subgroups highlights a gap in the current literature, underscoring the need for targeted research. CONCLUSION: The review underscores the necessity of a personalized approach in selecting temporary MCS devices for patients with acute cardiogenic shock, guided by specific patient characteristics and clinical scenarios. Future research should focus on addressing the identified evidence gaps through well-designed studies that provide robust subgroup-specific data, enabling clinicians to optimize treatment strategies and improve patient outcomes in this critical care context.

Flow capabilities of arterial and drainage cannulae during venoarterial extracorporeal membrane oxygenation: A simulation model.

BACKGROUND: Large cannulae can increase cannula-related complications during venoarterial extracorporeal membrane oxygenation (VA ECMO). Conversely, the ability for small cannulae to provide adequate support is poorly understood. Therefore, we aimed to evaluate a range of cannula sizes and VA ECMO flow rates in a simulated patient under various disease states. METHODS: Arterial cannulae sizes between 13 and 21 Fr and drainage cannula sizes between 21 and 25 Fr were tested in a VA ECMO circuit connected to a mock circulation loop simulating a patient with severe left ventricular failure. Systemic and pulmonary hypertension, physiologically normal, and hypotension were simulated by varying systemic and pulmonary vascular resistances (SVR and PVR, respectively). All cannula combinations were evaluated against all combinations of SVR, PVR, and VA ECMO flow rates. RESULTS: A 15 Fr arterial cannula combined with a 21 Fr drainage cannula could provide >4 L/min of total flow and a mean arterial pressure of 81.1 mmHg. Changes in SVR produced marked changes to all measured parameters, while changes to PVR had minimal effect. Larger drainage cannulae only increased maximum circuit flow rates when combined with larger arterial cannulae. CONCLUSION: Smaller cannulae and lower flow rates could sufficiently support the simulated patient under various disease states. We found arterial cannula size and SVR to be key factors in determining the flow-delivering capabilities for any given VA ECMO circuit. Overall, our results challenge the notion that larger cannulae and high flows must be used to achieve adequate ECMO support.

Point-of-Care Ultrasound (POCUS)-Guided Management of Cardiogenic Shock in COVID-19 Fulminant Myocarditis With Combined Veno-Arterial Extracorporeal Membrane Oxygenation and Impella (ECPELLA): A Case Report.

The COVID-19 pandemic, which has been raging globally, has been reported to cause not only pneumonia but also various cardiovascular diseases. In particular, myocarditis poses a serious risk if it becomes severe. As a characteristic of myocardial damage in this disease, right ventricular dysfunction is frequently reported, and biventricular failure is not uncommon. In cases where cardiogenic shock occurs, ECPELLA, which combines veno-arterial extracorporeal membrane oxygenation and Impella, is used for management. Currently, in Japan, ECPELLA is the central treatment for severe biventricular failure in the acute phase. However, its management method has not been established. Weaning from ECPELLA requires the following three conditions: (1) improvement of left ventricular function; (2) improvement of right ventricular function; and (3) optimization of circulating plasma volume. However, since these conditions change moment by moment, frequent and detailed assessments are necessary. Nevertheless, considering the need for isolation due to COVID-19, there are limitations on the tests that can be performed. In this regard, point-of-care ultrasound (POCUS) allows repeated bedside evaluations while maintaining infection protection. We report that in the case of severe COVID-19-related myocarditis, the use of POCUS enabled the preservation of cardiac function and appropriate timing for weaning from ECPELLA.

Intraoperative Catastrophic Acute Pulmonary Embolism: A Case Report.

This case report describes a 75-year-old female with a medical history including recurrent bowel obstruction due to sigmoid stricture, atrial fibrillation managed with rivaroxaban, a 50-year one pack-per-day smoking history, hypertension, hyperlipidemia, peripheral vascular disease with bilateral iliac stents (2015), stage III chronic kidney disease, and renal artery stenosis with bilateral stenting. She was transferred from outside hospital for an elective sigmoidectomy with ileorectal anastomosis following several recent admissions due to bowel obstruction that had been managed non-operatively. She was deemed optimized for surgery by the primary care team; however, during induction, she developed pulseless ventricular tachycardia requiring extensive resuscitative efforts. Intraoperative findings revealed biventricular failure and a clot in the right pulmonary artery. Despite aggressive treatment, including veno-arterial extracorporeal membrane oxygenation (VA ECMO), the patient's condition deteriorated, and life support was ultimately withdrawn. This case highlights the challenges of managing complex surgical patients and underscores the importance of multidisciplinary care in such cases.

Impact of Left Ventricular Unloading on Outcome of Heart Transplant Bridging With Extracorporeal Membrane Oxygenation Support in New Allocation Policy.

BACKGROUND: The new heart allocation policy places veno-arterial extracorporeal membrane oxygenation (VA-ECMO)-supported heart transplant (HT) candidates at the highest priority status. Despite increasing evidence supporting left ventricular (LV) unloading during VA-ECMO, the effect of LV unloading on transplant outcomes following bridging to HT with VA-ECMO remains unknown. METHODS AND RESULTS: From October 18, 2018 to March 21, 2023, 624 patients on VA-ECMO at the time of HT were identified in the United Network for Organ Sharing database and were divided into 2 groups: VA-ECMO alone (N=384) versus VA-ECMO with LV unloading (N=240). Subanalysis was performed in the LV unloading group: Impella (N=106) versus intra-aortic balloon pump (N=134). Recipient age was younger in the VA-ECMO alone group (48 versus 53 years, P=0.018), as was donor age (VA-ECMO alone, 29 years versus LV unloading, 32 years, P=0.041). One-year survival was comparable between groups (VA-ECMO alone, 88.0±1.8% versus LV unloading, 90.4±2.1%; P=0.92). Multivariable Cox hazard model showed LV unloading was not associated with posttransplant mortality after HT (hazard ratio, 0.92; P=0.70). Different LV unloading methods had similar 1-year survival (intra-aortic balloon pump, 89.2±3.0% versus Impella, 92.4±2.8%; P=0.65). Posttransplant survival was comparable between different Impella versions (Impella 2.5, versus Impella CP, versus Impella 5.0, versus Impella 5.5). CONCLUSIONS: Under the current allocation policy, LV unloading did not impact waitlist outcome and posttransplant survival in patients bridged to HT with VA-ECMO, nor did mode of LV unloading. This highlights the importance of a tailored approach in HT candidates on VA-ECMO, where routine LV unloading may not be universally necessary.

Why VA-ECMO should not be used routinely in AMI-Cardiogenic Shock.

This review summarizes the current evidence regarding efficacy and safety of venoarterial extracorporeal membrane oxygenation (VA-ECMO) in the setting of cardiogenic shock. Currently, there is evidence from 4 randomized controlled trials which all do not support a mortality benefit and increased complication rates by VA-ECMO. Based on current evidence, possible subgroups will be discussed and indications in selected very small patient groups be discussed.

Critical Circulatory Failure Accompanied With the aVR Sign Caused by Severe Graft Kinking Related to Acute Pseudoaneurysm Formation After Type A Acute Aortic Dissection Repair.

The aVR sign characterized by ST-segment elevation in lead aVR and diffuse ST-segment depression on the electrocardiogram indicates potential life-threatening conditions. We report the case of a 53-year-old male with a history of ascending aortic replacement for acute aortic dissection, who presented to our institution in shock. The initial electrocardiogram revealed the aVR sign, consisting of ST-segment elevation in lead aVR and ST-segment depression in leads II, III, aVF, and V3-6, leading to the initiation of salvage veno-arterial extracorporeal membrane oxygenation (ECMO) due to deteriorating hemodynamics. The aVR sign resolved shortly after ECMO initiation, and hemodynamics stabilized even with reduced ECMO flow. Subsequent coronary angiography showed no impaired coronary perfusion, whereas contrast-enhanced CT revealed severe supra-valvular stenosis due to pseudoaneurysm-induced graft kinking. The patient was then managed with emergency surgery for the pseudoaneurysm. In this report, we encountered a salvaged case of critical circulatory failure presenting with the aVR sign due to severe graft kinking caused by pseudoaneurysm formation.

Fat embolism syndrome: A severe case diagnosed early using dual-energy CT and saved with VA-ECMO and inhaled nitric oxide.

Diagnosing FES is difficult and time-consuming, and identify FES as an etiology of right ventricular volume overload for early diagnosis. Because FES is a reversible condition, even severe cases can bse treated if the patient survives the acute phase.

The importance of schistocytes in a patient in VA-ECMO.

The presence of schistocytes can be responsible for spurious thrombocytosis and spuriously low red blood count (RBC). The hemoglobin concentration will be correct (as the method usually used, destroys the red cells and converts a substantial proportion of the hemoglobin to a stable pigment) but mean corpuscular hemoglobin (MCH) is falsely high. The platelets and RBC histograms of the full blood count analyzers play an important role in the identification of schistocytes and must be carefully analyzed before reporting the previously full blood count parameters. In patients in ECMO, where can be expected the presence of a small number of schistocytes, this evaluation is particularly important to avoid wrong clinical decisions.