Cannula associated deep vein thromboses in COVID-19 patients supported with VV ECMO

BACKGROUND

VV ECMO is increasingly used as a rescue strategy for hypercarbic and hypoxic respiratory failure refractory to conventional management, and more than 14,000 patients with COVID-19 related respiratory failure have been supported with VV ECMO to date. One of the known complications of VV ECMO support is the development of cannula-associated deep vein thromboses (CaDVT). The purpose of this study was to identify the incidence of CaDVT in COVID-19 patients supported with VV ECMO as compared to non-COVID-19 patients. We hypothesized that due to the hypercoagulable state and longer duration of VV ECMO support required for patients with COVID-19, a higher incidence of CaDVT would be observed in these patients.

METHODS

This is a single center, retrospective observational study. About 291 non-trauma adult patients who were cannulated for VV ECMO and managed at our institution from January 1, 2014 to January 10, 2022 were included. The primary outcome was the presence of CaDVT 24 h after decannulation in COVID-19 versus non-COVID-19 patients. Our secondary outcome was continued presence of DVT on follow up imaging. CaDVT were defined as venous thrombi detected at prior cannulation sites.

RESULTS

Both groups had a high incidence of CaDVT. There was no significant difference in the incidence of CaDVT in COVID-19 patients compared to non-COVID-19 patients (95% vs 88%, p = 0.13). Patients with COVID-19 had an increased incidence of persistent CaDVT on repeat imaging (78% vs 56%, p = 0.03).

CONCLUSION

Given the high number of post-decannulation CaDVT in both groups, routine screening should be a part of post ECMO care in both populations. Repeat venous duplex ultrasound should be performed to assess for the need for ongoing treatment given the high incidence of CaDVT that persisted on repeat duplex scans.

Body mass index does not impact survival in COVID-19 patients requiring veno-venous extracorporeal membrane oxygenation

INTRODUCTION

With the increased demand for veno-venous extracorporeal membrane oxygenation (VV ECMO) during the COVID-19 pandemic, guidelines for patient candidacy have often limited this modality for patients with a body mass index (BMI) less than 40 kg/m2. We hypothesize that COVID-19 VV ECMO patients with at least class III obesity (BMI ≥ 40) have decreased in-hospital mortality when compared to non-COVID-19 and non-class III obese COVID-19 VV ECMO populations.

METHODS

This is a single-center retrospective study of COVID-19 VV ECMO patients from January 1, 2014, to November 30, 2021. Our institution used BMI ≥ 40 as part of a multi-disciplinary VV ECMO candidate screening process in COVID-19 patients. BMI criteria were not considered for exclusion criteria in non-COVID-19 patients. Univariate and multivariable analyses were performed to assess in-hospital mortality differences.

RESULTS

A total of 380 patients were included in our analysis: The COVID-19 group had a lower survival rate that was not statistically significant (65.7% vs.74.9%, p = .07). The median BMI between BMI ≥ 40 COVID-19 and non-COVID-19 patients was not different (44.5 vs 45.5, p = .2). There was no difference in survival between the groups (73.3% vs. 78.5%, p = .58), nor was there a difference in survival between the COVID-19 BMI ≥ 40 and BMI < 40 patients (73.3, 62.7, p= .29). Multivariable logistic regression with the outcome of in-hospital mortality was performed and BMI was not found to be significant (OR 0.99, 95% CI 0.89, 1.01; p = .92).

CONCLUSION

BMI ≥ 40 was not an independent risk factor for decreased in-hospital survival in this cohort of VV ECMO patients at a high-volume center. BMI should not be the sole factor when deciding VV ECMO candidacy in patients with COVID-19.

Case Report: emergent percutaneous directional thrombectomy in a patient with cardiogenic shock and large mobile thrombus in the right atrium

Background

New percutaneous techniques for the management of acute pulmonary embolism (PE) are emerging, but there is lack of data regarding the approach of mobile thrombus in the right chambers, with the added risk of potential thrombus dislodgement that may prevent from mechanical circulatory support devices to be implanted in unstable patients.

Case summary

We present the case of a 65-year-old male with cardiogenic shock of unknown aetiology, severe biventricular dysfunction, and large mobile thrombus in the right atrium. Mechanical circulatory support devices could not be implanted, and current thromboaspiration systems were either too small or not available at that time. However, the patient's condition deteriorated rapidly with thrombus in transit, hence, a novel approach was required: using a deflectable 14 Fr sheath, directional thrombectomy was performed, achieving complete extraction of the thrombi and allowing for circulatory support with extracorporeal membrane oxygenation (ECMO) to be implanted with outstanding results and progressive weaning of all intensive care measures.

Discussion

Despite the growing interest in the development of percutaneous strategies for acute PE, there is no evidence-based guidelines regarding the treatment of mobile right heart thrombus. Even though some cases of percutaneous right heart thrombectomy have been reported, it is still a challenging scenario, given the potential risk of thrombus dislodgement and atrial perforation. We describe a novel technique of percutaneous directional thrombectomy in a patient with cardiogenic shock of unknown aetiology and large mobile thrombi in the right atrium as a bridge to ECMO proving to be a feasible alternative to treat thrombus in transit.

Perioperative extracorporeal membrane oxygenation in pediatric congenital heart disease: Chinese expert consensus

BACKGROUND

Congenital heart disease (CHD) is one of the main supportive diseases of extracorporeal membrane oxygenation in children. The management of extracorporeal membrane oxygenation (ECMO) for pediatric CHD faces more severe challenges due to the complex anatomical structure of the heart, special pathophysiology, perioperative complications and various concomitant malformations. The survival rate of ECMO for CHD was significantly lower than other classifications of diseases according to the Extracorporeal Life Support Organization database. This expert consensus aims to improve the survival rate and reduce the morbidity of this patient population by standardizing the clinical strategy.

METHODS

The editing group of this consensus gathered 11 well-known experts in pediatric cardiac surgery and ECMO field in China to develop clinical recommendations formulated on the basis of existing evidences and expert opinions.

RESULTS

The primary concern of ECMO management in the perioperative period of CHD are patient selection, cannulation strategy, pump flow/ventilator parameters/vasoactive drug dosage setting, anticoagulation management, residual lesion screening, fluid and wound management and weaning or transition strategy. Prevention and treatment of complications of bleeding, thromboembolism and brain injury are emphatically discussed here. Special conditions of ECMO management related to the cardiovascular anatomy, haemodynamics and the surgical procedures of common complex CHD should be considered.

CONCLUSIONS

The consensus could provide a reference for patient selection, management and risk identification of perioperative ECMO in children with CHD. Video abstract (MP4 104726 kb).

The economic burden and long-term mortality in survivors of extracorporeal membrane oxygenation in South Korea

Background

The economic burden for extracorporeal membrane oxygenation (ECMO) survivors is a critical issue. We investigated the total healthcare costs for one year following ECMO support and its association with three-year all-cause mortality.

Methods

This population-based cohort study used data from the National Health Insurance Service (NHIS) in South Korea. Adult ECMO survivors (age ≥18 years who were alive ≥365 days following ECMO support) from January 1, 2005, to December 31, 2018, were included. The total healthcare costs for one year included all the expenses for hospital and outpatient clinic visits after discharge.

Results

In total, 6,044 patients were included in the final analysis comprising 3,566 (59.0%) in the cardiac indication group, 658 (10.9%) in the respiratory indication group, and 1,820 (30.1%) in the "other" group. The median total healthcare cost was United States Dollars (USD) 46,308.0 [interquartile range (IQR): 25,727.0-86,924.8]. The median ECMO support and hospital stay durations were three (IQR: 1-7) days and 25 (IQR: 15-31) days. In the multivariable Cox regression model, a USD 1,000 increase in the total healthcare cost was associated with an increase in the three-year all-cause mortality (hazard ratio, 1.01; 95% CI: 1.00-1.01; P=0.015).

Conclusions

After one year, ECMO survivors accrued USD 46,308 in healthcare costs in South Korea. An increase in the total healthcare cost was associated with a higher risk of three-year all-cause mortality among ECMO survivors.

Extracorporeal membrane oxygenation as a bridge to durable mechanical circulatory support or heart transplantation

BACKGROUND

Patients with cardiogenic shock may require extracorporeal membrane oxygenation (ECMO) prior to durable mechanical circulatory support (dMCS) or heart transplantation (HTx).

METHODS

We investigated the clinical characteristics and outcomes of adult patients with ECMO support as bridge to dMCS or HTx between 1/1/13 and 12/31/20.

RESULTS

Of 57 patients who underwent bridging ECMO, 41 (72%) received dMCS (approximately half with biventricular support) and 16 (28%) underwent HTx, 13 (81%) after the 2018 UNOS allocation system change. ECMO → HTx patients had shorter ventilatory time (3.5 vs 7.5 days; p = 0.018), ICU stay (6 vs 18 days; p = 0.001), and less need for inpatient rehabilitation (18.8% vs 57.5%; p = 0.016). The 1-year survival post HTx was 81.3% in the ECMO → HTx group and 86.4% in the ECMO → dMCS group (p = 0.11). For those patients in the ECMO → dMCS group who did not undergo HTx, 1-year survival was significantly lower, 31.6% (p = 0.001).

CONCLUSION

Patients on ECMO who undergo HTx, with or without dMCS bridge, have acceptable post-HTx survival. These findings suggest that HTx from ECMO is a viable option for carefully selected patients deemed acceptable to proceed with definitive advanced therapies, especially in the era of the new UNOS allocation system.

The dominant left ventricular assist device: lessons from an era

The production and distribution of the HeartWare ventricular assist device has come to an abrupt end, but with this end comes the opportunity to reflect upon lessons learned from its lifespan. Running counter to the standard of evidence-based practice, the era of the HeartWare ventricular assist device was marred with fragmented data in relation to its primary counterpart, the HeartMate III. This created an incomplete understanding of devices, limited individualized patient care, and effectively positioned providers to make inferences regarding device superiority. We briefly review pertinent literature on this topic among the most commonly implanted durable devices from the era, detail the inherent limitations of this data, and argue the necessity of randomized clinical trials among novel devices towards the optimization of patient care.

[ECMO for post cardiotomy refractory cardiogenic shock: Experience of the cardiac surgery department of the Grenoble Alpes University Hospital]

OBJECTIVE

The objective of our study is to detail our experience relating to ECMO implantations for post-cardiotomy refractory shock, by analyzing the pre-ECMO factors (history, type of surgery, LVEF), factors relating to ECMO (implantation time, duration) and post-ECMO factors (weaning, complications) in order to highlight those possibly associated with high mortality.

METHODS

This is a univariate and multivariate retrospective study of ECMO data implemented between 2011 and 2019 at the Grenoble Alpes University Hospital Center following cardiac surgery. The time to implantation of ECMO was less than 3hours (intraoperative) between 3 and 24hours (early postoperative) and between 24 and 48hours after aortic unclamping (late postoperative). Preoperative or postoperative intra-aortic balloon counterpulsation (CPBIA) could be associated.

RESULTS

114 veino-arterial ECMOs were implanted for refractory cardiogenic shock after 5702 cardiac surgeries (1.9%) with a survival rate of 30.7%. The mean age of the patients was 68.6+- 10.5 years. The implantation of ECMO was performed intraoperatively in 71 patients (62.2%), early postoperatively in 22 patients (19.2%) and late postoperatively in 21 patients (18.4%). The duration of assistance was less than 48hours in 27 patients (23.6%), between 48hours and one week in 58 patients (50.9%) and more than one week in 29 patients (25.5%). Univariate analysis revealed a statistically significant association between mortality rate and male sex (P=0.002), association absent with other preoperative characteristics, delay in implantation of ECMO, installation of CPBIA, post-operative characteristics and resuscitation suites. Multivariate analysis of the entire study population demonstrated that the use of ECMO for cardio-respiratory arrest was the only independent risk factor for mortality (OR=7.57 [1.41-40, 62]). After multivariate reanalysis excluding patients with ECMO placement for cardio respiratory arrest, age, preoperative renal failure, type of procedure and EuroSCORE II were risk factors for mortality.

CONCLUSION

In this study, male gender, type of intervention, occurrence of cardiac arrest were significantly associated with the death rate. A study of greater power, multicentric, and with a larger sample, will have to be carried out to reach significance.

Intermittent Occlusion of the Superior Vena Cava Reduces Cardiac Filling Pressures in Preclinical Models of Heart Failure

Congestion is a major determinant of clinical outcomes in heart failure (HF). We compared the acute hemodynamic effects of occlusion of the superior (SVC) versus the inferior vena cava (IVC) and tested a novel SVC occlusion system in swine models of HF. IVC occlusion acutely reduced left ventricular (LV) systolic and diastolic pressures, LV volumes, cardiac output (CO), and mean arterial pressure (MAP). SVC occlusion reduced LV diastolic pressure and volumes without affecting CO or MAP. The preCARDIA system is a balloon occlusion catheter and pump console which enables controlled delivery and removal of fluid into the occlusion balloon. At 6, 12, and 18 h, SVC therapy with the system provided a sustained reduction in cardiac filling pressures with stable CO and MAP. Intermittent SVC occlusion is a novel approach to reduce biventricular filling pressures in HF. The VENUS-HF trial will test the safety and feasibility of SVC therapy in HF.

High-risk PCI under support of a pulsatile left ventricular assist device - First German experience with the iVAC2L system

BACKGROUND

During high-risk percutaneous coronary intervention (PCI) complications may occur, leading to unstable hemodynamic conditions. Circulatory support devices might help to intercept these conditions by supporting cardiac output. We investigated in a prospective trial the performance of the pulsatile iVAC2L system in the setting of high-risk PCI.

METHODS

Circulatory support by the iVAC2L device was attempted in 20 consecutive patients (three females, mean age 72 ± 9 years, LVEF 44 ± 12%) undergoing high-risk PCI. Aortic pressure data were collected after device placement and immediately after PCI.

RESULTS

Successful device placement was achieved in 17 (85%) patients; kinking of iliac artery and device length limited correct device placement in the remaining three patients. PCI success was 100%. With ongoing support (overall support time 122 ± 32min) systolic, diastolic and mean blood pressure increased significantly and kept the higher level until device removal. Critical events occurred in three patients (massive vasospasm, coronary perforation, no-flow in LCA after wire placement), but the iVAC2L device helped to maintain stable hemodynamic conditions with no need for cardiopulmonary resuscitation. Serial controls of hemolysis related parameters in a subgroup of ten patients revealed no significant device related hemolysis after the performance of the iVAC2l system.

CONCLUSIONS

High-risk PCI under hemodynamic support by the iVAC2L device is feasible and safe. Aortic pressure increases with ongoing support. The device helps to stabilize hemodynamic situations if complications occur.

Limb ischemia in peripheral veno-arterial extracorporeal membrane oxygenation: a narrative review of incidence, prevention, monitoring, and treatment

Veno-arterial extracorporeal membrane oxygenation (V-A ECMO) is an increasingly adopted life-saving mechanical circulatory support for a number of potentially reversible or treatable cardiac diseases. It is also started as a bridge-to-transplantation/ventricular assist device in the case of unrecoverable cardiac or cardio-respiratory illness. In recent years, principally for non-post-cardiotomy shock, peripheral cannulation using the femoral vessels has been the approach of choice because it does not need the chest opening, can be quickly established, can be applied percutaneously, and is less likely to cause bleeding and infections than central cannulation. Peripheral ECMO, however, is characterized by a higher rate of vascular complications. The mechanisms of such adverse events are often multifactorial, including suboptimal arterial perfusion and hemodynamic instability due to the underlying disease, peripheral vascular disease, and placement of cannulas that nearly occlude the vessel. The effect of femoral artery damage and/or significant reduced limb perfusion can be devastating because limb ischemia can lead to compartment syndrome, requiring fasciotomy and, occasionally, even limb amputation, thereby negatively impacting hospital stay, long-term functional outcomes, and survival. Data on this topic are highly fragmentary, and there are no clear-cut recommendations. Accordingly, the strategies adopted to cope with this complication vary a great deal, ranging from preventive placement of antegrade distal perfusion cannulas to rescue interventions and vascular surgery after the complication has manifested.This review aims to provide a comprehensive overview of limb ischemia during femoral cannulation for VA-ECMO in adults, focusing on incidence, tools for early diagnosis, risk factors, and preventive and treating strategies.

[Antagonistic function of the heart muscle : Part II: Clinical implications]

In the hypertrophic heart the myostructural afterload in the form of endoepicardial networks is predominant, which enhances myocardial hypertrophy. The intrinsic antagonism is derailed. Likewise, the connective tissue scaffold, i.e. the stromatogenic afterload, is enriched in the response to the derailment of antagonism in a hypertrophic heart up to regional captivation of the heart musculature. Due to the selective susceptibility of the auxotonic, contracting oblique transmural myocardial network for low dose negative inotropic medication, this promises to attenuate progress in myocardial hypertrophy. Volume reduction surgery is most effective in reducing wall stress as long as the myocardium is not critically fettered by fibrosis. The use of external mechanical circulatory support is then effective if the heart is supported in its resting mode, which means around a middle width and at minimal amplitude of motion. The takotsubo cardiomyopathy might possibly reflect an isolated, extreme stimulation of the intrinsic antagonism as a response to hormonally induced sensitization of the myocardium to catecholamine. A particular significant conclusion with respect to the diseased heart is that clinical diagnostics need new impulses with a focus on the analysis of local motion patterns and on myocardial stiffness reflecting disease-dependent antagonistic intensity. This would become a relevant diagnostic marker if corresponding (noninvasive) measurement techniques would become available.

Effects of Preoperative Curcumin on the Inflammatory Response During Mechanical Circulatory Support: A Porcine Model

Background

Curcumin is a polyphenol extracted from the turmeric plant which may have anti-inflammatory properties. We hypothesized that curcumin pretreatment would result in a reduction in inflammatory markers in a large animal model of extracorporeal support.

Methods

A total of seven samples were obtained from three swine treated with curcumin and 16 samples were obtained from six swine in the control group (procedure terminated in two swine before last sample could be obtained).

Results

Samples for interleukin (IL)-8 and IL-1b had concentrations below the limit of detection at all points and were discarded from further analysis. IL-6, tumor necrosis factor (TNF)-α, and intercellular adhesion molecule (ICAM)-1 concentrations were lower in curcumin pretreated animals when compared to control animals. This decrease was statistically significant for TNF-α, and ICAM-1.

Conclusions

This project may provide information for the development of a translational study in humans as we noted that curcumin pretreatment in a large animal model of cardiopulmonary bypass (CPB) and extracorporeal support resulted in a decrease in TNF-α and ICAM-1 expression compared to control animals.

First successful prevention of cardiopulmonary resuscitation during high-risk percutaneous coronary intervention by use of a pulsatile left ventricular assist device: baptism of fire of the iVAC2L device: a case report

Introduction

Efforts in percutaneous coronary intervention (PCI) lead to interventional treatment of complex stenoses as an alternative to coronary bypass surgery. Nevertheless, complications during PCI can occur with sudden need for circulatory support. Circulatory support devices are helpful tools during high-risk PCI to generate additional output or maintain sufficient circulation in critical situations.

Case description

We report the case of the first successful prevention of cardiopulmonary resuscitation by use of transfemoral pulsatile ventricular assist device with up to 2l additional cardiac output during a high-risk PCI in an 80-year old man with complex stenosis and a history of ventricular fibrillation during prior coronary angiography.

Discussion

The device managed to maintain an adequate circulation during massive vasospasm and bradycardia. The iVAC2L seems to be a useful tool in high-risk PCI. Its general effect on haemodynamics and patients' outcome has to be evaluated in larger multi-centre studies.

[Cardiogenic shock : Current evidence]

This CME article addresses the pathophysiology, incidence, current survival outcome and treatment options for patients with cardiogenic shock as a complication of acute myocardial infarction. The shock spiral of left heart failure due to cardiac infarction, subsequent vasoconstriction and paradoxical vasodilation due to the systemic inflammation response syndrome (SIRS) is a vicious circle which must be interrupted. Treatment focuses on the evidence from randomized clinical trials and the current guideline recommendations. With respect to interventional and surgical treatment the question of culprit lesion vs. complete revascularization is still unsolved. For medicinal treatment acetylsalicylic acid (ASA) and heparin are more often supplemented with prasugrel and ticagrelor. In the case of inotropes, dobutamine remains the first-line treatment option and for vasopressors norepinephrine. The calcium sensitizer levosimendan has not provided the hoped for superiority over conventional treatment in randomized trials. The use of intra-aortic balloon pumps (IABP) is no longer recommended as circulatory support in acute heart failure (reduced to class III). The use of percutaneous implantable mechanical circulatory support devices has not shown a survival benefit in the few randomized trials carried out so far even when compared with IABP, due to increased bleeding complications.

[Indications and strategies in mechanical circulatory support : Rise of the machines?]

Terminal heart failure is an emerging problem with a continuously growing number of diseased patients worldwide. Because of the limited number of donor hearts, mechanical circulatory support is increasingly becoming an integral part of surgical treatment for end-stage heart failure, especially in patients deemed for destination therapy. Accurate patient selection, appropriate indication, and the optimal implantation time point guarantee a good outcome for these patients. This review article gives a systematic overview of the possible indication settings and treatment strategies for various patient groups in need of mechanical circulatory support.

Anesthesia for Heart Transplantation

This article seeks to evaluate current practices in heart transplantation. The goals of this article were to review current practices for heart transplantation and its anesthesia management. The article reviews current demographics and discusses the current criteria for candidacy for heart transplantation. The process for donor and receipt selection is reviewed. This is followed by a review of mechanical circulatory support devices as they pertain to heart transplantation. The preanesthesia and intraoperative considerations are also discussed. Finally, management after transplantation is also reviewed.

Cardiac Arrest in Acute Myocardial Infarction: Concept of Circulatory Support With Mechanical Chest Compression and Impella to Facilitate Percutaneous Coronary Intervention

Cardiogenic shock in the context of acute ST-elevation myocardial infarction (STEMI) remains a challenge to manage and results in significant mortality and morbidity, cardiac arrest in this setting even more so. The increase in myocardial oxygen demand and consumption with the use of inotropes is recognised as increasing mortality. Alternatives include the intra-aortic balloon pump (IABP), which has yet to be shown to improve outcomes, and extracorporeal membrane oxygenation (ECMO), which requires super-specialised techniques not widely available. We report a case of Anterior STEMI from a left main stem occlusion suffering with cardiac arrest on reaching the catheter laboratory table necessitating external mechanical compression with an Autopulse™. The patient remained in pulseless electrical activity (PEA) throughout, and was Autopulse dependent despite successful percutaneous coronary intervention (PCI). An Impella^® was inserted for additional mechanical support and facilitated successful weaning from cardiopulmonary resuscitation (CPR). Despite 105minutes without a spontaneous output, we describe the first documented case of simultaneous use of Impella with mechanical CPR with a successful outcome; demonstrating a potential technique of good mechanical haemodynamic support to aide early revascularisation that may have potential utility in the treatment of cardiogenic shock and arrest.

Minimally invasive approach for percutaneous CentriMag right ventricular assist device support using a single PROTEKDuo Cannula

Background

Right ventricular failure is a serious complication after left ventricular assist device placement.

Case Presentation

A 70-year-old male in decompensated heart failure with right ventricular failure after the placement of a left ventricular assist device. A single dual-lumen PROTEKDuo cannula was inserted percutaneously via the internal jugular vein to draw blood from the right atrium and return into the pulmonary artery using the CentriMag system, by passing the failing ventricle. The patient was successfully weaned from right ventricular assist device.

Conclusions

In comparison to two-cannula conventional procedures, this right ventrivular assist device system improves patient rehabilitation and minimizes blood loss and risk of infection, while shortening procedure time and improving clinical outcomes in right ventricular failure.

Technique for minimizing and treating driveline infections

Left ventricular assist devices (LVADs) are increasingly utilized in the management of advanced heart failure. A transcutaneous driveline is necessary to power the LVAD, and although this technology has improved over the years in terms of smaller size and increased durability, driveline complications continue to develop in up to 20% of all devices implanted. Driveline infections are associated with significant morbidity and mortality. As more patients live longer with ventricular assist devices, minimizing driveline infections is paramount. A systematic, multidisciplinary approach can be used to develop a strategy to prevent, recognize and treat driveline infections. In this paper, we describe our approach to driveline management which has resulted in zero driveline infections between January 2012 and March 2014.

Accelerated heart function recovery after therapeutic plasma exchange in patient treated with biventricular mechanical circulatory support for severe peripartum cardiomyopathy

We describe a case of severe peripartum cardiomyopathy treated with biventricular mechanical circulatory support, where rapid haemodynamic recovery was observed after therapeutic plasma exchange, used as an adjunct to the inhibition of prolactin release. The patient recovered and after 2 months was discharged from the hospital without clinical symptoms of heart disease.

Hold or fold--proteins in advanced heart failure and myocardial recovery

Advanced heart failure (AHF) describes the subset of heart failure patients refractory to conventional medical therapy. For some AHF patients, the use of mechanical circulatory support (MCS) provides an intermediary "bridge" step for transplant-eligible patients or an alternative therapy for transplant-ineligible patients. Over the past 20 years, clinical observations have revealed that approximately 1% of patients with MCS undergo significant reverse remodeling to the point where the device can be explanted. Unfortunately, it is unclear why some patients experience durable, sustained myocardial remission, while others redevelop heart failure (i.e. which hearts "hold" and which hearts "fold"). In this review, we outline unmet clinical needs related to treating patients with MCS, provide an overview of protein dynamics in the reverse-remodeling process, and propose specific areas where we expect MS and proteomic analyses will have significant impact on our understanding of disease progression, molecular mechanisms of recovery, and provide new markers with prognostic value that can positively impact patient care. Complimentary perspectives are provided with the goal of making this important topic accessible and relevant to both a clinical and basic science audience, as the intersection of these disciplines is required to advance the field.

Argentina]

INTRODUCTION

Mechanical circulatory support provides oxygen to the tissues in patients with cardiac and/or respiratory reversible disease refractory to conventional treatments.

OBJECTIVE

The aim of this study is to show our initial results of mechanical circulatory support in children with heart disease.

METHOD

Retrospective cohort between March 2006 and March 2012. Demographic data (age, sex, weight, cardiac diagnosis), surgery (technique, pump, aortic cross clamping time) and mechanical circulatory support (type of assistance, indication, duration, complications and outcome) were collected.

RESULTS

Thirty-three patients were supported (1.3% of all surgeries), extracorporeal membrane oxygenation 32 cases and one ventricular assist device. The median age 7.4 months (one day-18 years) and weight 6kg (2.3-75). The most frequent cardiac malformations supported were the transpositions of the great arteries associated with other anomalies and the corrected transpositions (ventricular inversion or double discordance). The most common reason for admission was post-cardiotomy biventricular dysfunction. Twenty-eight patients were supported in the postoperative period, 4 in the preoperative period and in one with myocarditis. Median days of support were 3 days (1-10). The most common complications were infection (21%), bleeding (21%). Elective decannulation was achieved in 94% of cases. Hospital discharge survival: 52%.

CONCLUSIONS

The mechanical circulatory support in our institution is a safe and standard procedure. We have been using it in a small number of cases with a similar survival to that reported internationally. This complex procedure is widely justified because it allows for the recovery of more than half of the patients who otherwise would have died.

Hemodynamic Support: Science and Evaluation of the Assisted Circulation with Percutaneous Assist Devices

Pathophysiologic mechanisms that lead to hemodynamic abnormalities in cardiogenic shock (including hypotension, hypoperfusion, and elevated venous pressures) are reviewed within the framework of pressure-volume analysis. This approach provides the foundation for understanding how different modes of circulatory support impact key these cardiovascular parameters in various clinical settings. Four fundamentally different modes of circulatory support are reviewed, including aortic counterpulsation, left atrial-to-arterial pumping, right atrial-to-arterial pumping, and left ventricular-to-aortic pumping. Each approach has a distinct hemodynamic fingerprint with regard to effects on the ventricular pressure-volume loop and key hemodynamic and metabolic parameters.