Microaxial Flow Pump or Standard Care in Infarct-Related Cardiogenic Shock.

BACKGROUND: The effects of temporary mechanical circulatory support with a microaxial flow pump on mortality among patients with ST-segment elevation myocardial infarction (STEMI) complicated by cardiogenic shock remains unclear. METHODS: In an international, multicenter, randomized trial, we assigned patients with STEMI and cardiogenic shock to receive a microaxial flow pump (Impella CP) plus standard care or standard care alone. The primary end point was death from any cause at 180 days. A composite safety end point was severe bleeding, limb ischemia, hemolysis, device failure, or worsening aortic regurgitation. RESULTS: A total of 360 patients underwent randomization, of whom 355 were included in the final analysis (179 in the microaxial-flow-pump group and 176 in the standard-care group). The median age of the patients was 67 years, and 79.2% were men. Death from any cause occurred in 82 of 179 patients (45.8%) in the microaxial-flow-pump group and in 103 of 176 patients (58.5%) in the standard-care group (hazard ratio, 0.74; 95% confidence interval [CI], 0.55 to 0.99; P = 0.04). A composite safety end-point event occurred in 43 patients (24.0%) in the microaxial-flow-pump group and in 11 (6.2%) in the standard-care group (relative risk, 4.74; 95% CI, 2.36 to 9.55). Renal-replacement therapy was administered to 75 patients (41.9%) in the microaxial-flow-pump group and to 47 patients (26.7%) in the standard-care group (relative risk, 1.98; 95% CI, 1.27 to 3.09). CONCLUSIONS: The routine use of a microaxial flow pump with standard care in the treatment of patients with STEMI-related cardiogenic shock led to a lower risk of death from any cause at 180 days than standard care alone. The incidence of a composite of adverse events was higher with the use of the microaxial flow pump. (Funded by the Danish Heart Foundation and Abiomed; DanGer Shock ClinicalTrials.gov number, NCT01633502.).

Matrix-Degrading Enzyme Expression and Aortic Fibrosis During Continuous-Flow Left Ventricular Mechanical Support.

BACKGROUND: The effects of nonphysiological flow generated by continuous-flow (CF) left ventricular assist devices (LVADs) on the aorta remain poorly understood. OBJECTIVES: The authors sought to quantify indexes of fibrosis and determine the molecular signature of post-CF-LVAD vascular remodeling. METHODS: Paired aortic tissue was collected at CF-LVAD implant and subsequently at transplant from 22 patients. Aortic wall morphometry and fibrillar collagen content (a measure of fibrosis) was quantified. In addition, whole-transcriptome profiling by RNA sequencing and follow-up immunohistochemistry were performed to evaluate CF-LVAD-mediated changes in aortic mRNA and protein expression. RESULTS: The mean age was 52 ± 12 years, with a mean duration of CF-LVAD of 224 ± 193 days (range 45-798 days). There was a significant increase in the thickness of the collagen-rich adventitial layer from 218 ± 110 µm pre-LVAD to 410 ± 209 µm post-LVAD (P < 0.01). Furthermore, there was an increase in intimal and medial mean fibrillar collagen intensity from 22 ± 11 a.u. pre-LVAD to 41 ± 24 a.u. post-LVAD (P < 0.0001). The magnitude of this increase in fibrosis was greater among patients with longer durations of CF-LVAD support. CF-LVAD led to profound down-regulation in expression of extracellular matrix-degrading enzymes, such as matrix metalloproteinase-19 and ADAMTS4, whereas no evidence of fibroblast activation was noted. CONCLUSIONS: There is aortic remodeling and fibrosis after CF-LVAD that correlates with the duration of support. This fibrosis is due, at least in part, to suppression of extracellular matrix-degrading enzyme expression. Further research is needed to examine the contribution of nonphysiological flow patterns on vascular function and whether modulation of pulsatility may improve vascular remodeling and long-term outcomes.

Neutrophil injury and function alterations induced by high mechanical shear stress with short exposure time.

High mechanical shear stresses (HMSS) can cause damage to blood, which manifests as morphologic changes, shortened life span, biochemical alterations, and complete rupture of blood cells and proteins, leading to the alterations of normal blood function. The aim of this study is to determine the state of neutrophil activation and function alterations caused by HMSS with short exposure time relevant to ventricular assist devices. Blood from healthy donors was exposed to three levels of HMSS (75Pa, 125Pa, and 175Pa) for a short exposure time (0.5 s) using our Couette-type blood-shearing device. Neutrophil activation (Mac-1, platelet-neutrophil aggregates) and surface expression levels of two key functional receptors (CD62L and CD162) on neutrophils were evaluated by flow cytometry. Neutrophil phagocytosis and transmigration were also examined with functional assays. Results showed that the expression of Mac-1 on neutrophils and platelet-neutrophil aggregates increased significantly while the level of CD62L expression on neutrophils decreased significantly after the exposure to HMSS. The Mac-1 expression progressively increased while the CD62L expression progressively decreased with the increased level of HMSS. The level of CD162 expression on neutrophils slightly increased after the exposure to HMSS, but the increase was not significant. The phagocytosis assay data revealed that the ability of neutrophils to phagocytose latex beads coated with fluorescently labeled rabbit IgG increased significantly with the increased level of HMSS. The transmigration ability of neutrophils slightly increased after the exposure to HMSS, but did not reach a significant level. In summary, HMSS with a short exposure time of 0.5 seconds could induce neutrophil activation, platelet-neutrophil aggregation, shedding of CD62L receptor, and increased phagocytic ability. However, the exposure to the three levels of HMSS did not cause a significant change in neutrophil transmigration capacity and shedding of CD162 receptor on neutrophils.

Modeling Clot Formation of Shear-Injured Platelets in Flow by a Dissipative Particle Dynamics Method.

The regions with high non-physiological shear stresses (NPSS) are inevitable in blood-contacting medical devices (BCMDs) used for mechanically assisted circulatory support. NPSS can cause platelet activation and receptor shedding potentially resulting in the alteration of hemostatic function. In this study, we developed a dissipative particle dynamics model to characterize clot formation (platelet-collagen and inter-platelet adhesion) of NPSS-traumatized blood at a vascular injury site. A rectangular tube of 50 × 50 × 200 µm with an 8 × 8 µm collagen-coated area was modeled as a small blood vessel and perfusion with blood. Clot formation dynamics during perfusion was simulated. NPSS-traumatized blood was modeled to have more activated platelet and fewer adhesion receptors with weakened inter-platelet binding. Computational results showed that clots grew at a faster rate while the structure of the clots was less stable and collapsed more frequently for NPSS-traumatized blood compared with normal blood. The finding that NPSS-traumatized platelets could result in quicker but more easily breakable blood clots at injury sites may explain why increased risks of thrombotic and bleeding complications occurred concurrently in patients implanted with BCMDs.

Frequency and Impact of Bleeding on Outcome in Patients With Cardiogenic Shock.

OBJECTIVES: This study sought to determine frequency, associated factors, and impact of bleeding in infarct-related cardiogenic shock. BACKGROUND: Early revascularization is associated with improved survival in patients with acute myocardial infarction complicated by cardiogenic shock. On the downside, invasive treatment and accompanying antithrombotic therapies are associated with an increased bleeding risk. Prospective data assessing the incidence, severity, risk factors, and prognostic implication of bleeding in patients with cardiogenic shock are scarce. METHODS: As a pre-defined subanalysis of the CULPRIT-SHOCK (PCI Strategies in Patients with Acute Myocardial Infarction and Cardiogenic Shock) randomized trial, we examined distribution of bleeding events in 684 patients with infarct-related cardiogenic shock and compared patients with any bleeding to those without. RESULTS: A total of 21.5% patients experienced at least 1 bleeding event until 30 days after randomization. The vast majority of bleeding (57%) occurred within the first 2 days of hospitalization. Patients with bleeding had prolonged catecholamine treatment and mechanical ventilation and there was a significant association with sepsis, peripheral ischemic complications, new atrial fibrillation, and ventricular fibrillation. In multivariable analysis, bleeding was associated with a significantly higher mortality (hazard ratio: 2.11; 95% confidence interval: 1.63 to 2.75; p < 0.0001). Treatment with active mechanical support by extracorporeal membrane oxygenation or Impella emerged as the major risk factor for bleeding. CONCLUSIONS: Risk of bleeding in infarct-related cardiogenic shock is high and associated with increased mortality.

Surgical Results for Infective Endocarditis Complicated With Cardiogenic Shock.

BACKGROUND: Infective endocarditis remains associated with substantial mortality and morbidity rates, and the presence of acute heart failure (AHF) compromises clinical results after valve surgery; however, little is known in cardiogenic shock (CGS) patients. This study evaluated the clinical results and risk of mortality in CGS patients after valve surgery.Methods and Results:This study enrolled 585 patients who underwent valve surgery for active endocarditis at 14 institutions between 2009 and 2017. Of these patients, 69 (12%) were in CGS, which was defined as systolic blood pressure <80 mmHg and severe pulmonary congestion, requiring mechanical ventilation and/or mechanical circulatory support, preoperatively. The predictors of CGS were analyzed, and clinical results of patients with non-CGS AHF (n=215) were evaluated and compared.Staphylococcus aureusinfection (odds ratio [OR] 2.19; P=0.044), double valve involvement (OR 3.37; P=0.003), and larger vegetation (OR 1.05; P=0.036) were risk factors for CGS. Hospital mortality occurred in 27 (13%) non-CGS AHF patients and in 15 (22%) CGS patients (P=0.079). Overall survival at 1 and 5 years in CGS patients was 76% and 69%, respectively, and there were no significant differences in overall survival compared with non-CGS AHF patients (P=1.000). CONCLUSIONS: Clinical results after valve surgery in CGS patients remain challenging; however, mid-term results were equivalent to those of non-CGS AHF patients.

Catheter Ablation in Patients With Cardiogenic Shock and Refractory Ventricular Tachycardia.

BACKGROUND: There is paucity of data regarding radiofrequency ablation for ventricular tachycardia (VT) in patients with cardiogenic shock and concomitant VT refractory to antiarrhythmic drugs on mechanical support. METHODS: Patients undergoing VT ablation at our center were enrolled in a prospectively maintained registry and screened for the current study (2010-2017). RESULTS: All 21 consecutive patients with cardiogenic shock and concomitant refractory ventricular arrhythmia undergoing bailout ablation due to inability to wean off mechanical support were included. Median age was 61 years, 86% were men, median left ventricular ejection fraction was 20%, 81% had ischemic cardiomyopathy, and PAINESD score was 18±5. The type of mechanical support in place before the procedure was intra-aortic balloon pump in 14 patients (67%), Impella CP in 2, extracorporeal membrane oxygenation in 2, extracorporeal membrane oxygenation and intra-aortic balloon pump in 2, and extracorporeal membrane oxygenation and Impella CP in 1. Endocardial voltage maps showed myocardial scar in 19 patients (90%). The clinical VTs were inducible in 13 patients (62%), whereas 6 patients had premature ventricular contraction-induced ventricular fibrillation/VT (29%), and VT could not be induced in 2 patients (9%). Activation mapping was possible in all 13 with inducible clinical VTs. Substrate modification was performed in 15 patients with scar (79%). After ablation and scar modification, the arrhythmia was noninducible in 19 patients (91%). Seventeen (81%) were eventually weaned off mechanical support successfully, but 6 (29%) died during the index admission from persistent cardiogenic shock. Patients who had ventricular arrhythmia and cardiogenic shock on presentation had a trend toward lower in-hospital mortality compared with those who presented with cardiogenic shock and later developed ventricular arrhythmia. CONCLUSIONS: Bailout ablation for refractory ventricular arrhythmia in cardiogenic shock allowed successful weaning from mechanical support in a large proportion of patients. Mortality remains high, but the majority of patients were discharged home and survived beyond 1 year.

Mechanical Circulatory Support Combined With Immunosuppression for the Treatment of Giant Cell Myocarditis　- A Single-Center Experience in Japan.

BACKGROUND: The therapeutic strategy for giant cell myocarditis (GCM) remains controversial, so we reviewed the clinical status of Japanese patients with GCM.Methods and Results:We retrospectively reviewed 6 consecutive patients with GCM requiring percutaneous mechanical circulatory support (p-MCS), with 3 further requiring ventricular assist devices. One patient died during p-MCS. Cardiac function improved in the other 5 with immunosuppressive therapy, but only 3 patients treated with dual immunosuppressants, including cyclosporine (CyA), achieved >1-year survival. CONCLUSIONS: The prognosis of patients with fulminant GCM is poor, but a treatment that combines MCS and early administration of CyA-based immunosuppressants will be useful.

Outcome of rescue ablation in patients with refractory ventricular electrical storm requiring mechanical circulation support.

BACKGROUND: The management of refractory electrical storm (ES) requiring mechanical circulation support (MCS) remains a clinical challenge in structural heart disease (SHD). OBJECTIVE: The study sought to explore the 30-day and 1-year outcome of rescue ablation for refractory ES requiring MCS in SHD. METHODS: A total of 81 patients (mean age: 55.3 ± 18.9, 73 men [90.1%]) undergoing ablation were investigated, including 26 patients with ES requiring MCS (group 1) and 55 patients without (group 2). The 30-day and 1-year outcome, including mortality and recurrent ventricular tachyarrhythmias (VAs) receiving appropriate implantable cardioverter defibrillators therapies, were assessed. RESULTS: The patients in group 1 were characterized by older age, more ischemic cardiomyopathies, worse left ventricular ejection fraction, and more comorbidities. Thirty days after ablation, overall events were seen in 15 patients (mortality in 10 and recurrent VA in 7), including pumping failure-related mortality in 6 (60%). During a 30-day follow-up, higher mortality was noted in group 1. After a 1-year follow-up, in spite of the higher mortality in group 1 (P < .001), the overall events and VA recurrences were similar between these two groups (P = .154 and P = .466, respectively). There was a significant reduction of VA burden in both groups and two patients had recurrent ES. CONCLUSION: Higher 30-day mortality was observed in patients undergoing rescue ablation for refractory ES requiring MCS, and pumping failure was the major cause of periprocedural death. Rescue ablation successfully prevented VA recurrences and resulted in a comparable 1-year prognosis between ES with and without MCS.

Usefulness of regional right ventricular and right atrial strain for prediction of early and late right ventricular failure following a left ventricular assist device implant: A machine learning approach.

BACKGROUND: Identifying candidates for left ventricular assist device surgery at risk of right ventricular failure remains difficult. The aim was to identify the most accurate predictors of right ventricular failure among clinical, biological, and imaging markers, assessed by agreement of different supervised machine learning algorithms. METHODS: Seventy-four patients, referred to HeartWare left ventricular assist device since 2010 in two Italian centers, were recruited. Biomarkers, right ventricular standard, and strain echocardiography, as well as cath-lab measures, were compared among patients who did not develop right ventricular failure (N = 56), those with acute-right ventricular failure (N = 8, 11%) or chronic-right ventricular failure (N = 10, 14%). Logistic regression, penalized logistic regression, linear support vector machines, and naïve Bayes algorithms with leave-one-out validation were used to evaluate the efficiency of any combination of three collected variables in an "all-subsets" approach. RESULTS: Michigan risk score combined with central venous pressure assessed invasively and apical longitudinal systolic strain of the right ventricular-free wall were the most significant predictors of acute-right ventricular failure (maximum receiver operating characteristic-area under the curve = 0.95, 95% confidence interval = 0.91-1.00, by the naïve Bayes), while the right ventricular-free wall systolic strain of the middle segment, right atrial strain (QRS-synced), and tricuspid annular plane systolic excursion were the most significant predictors of Chronic-RVF (receiver operating characteristic-area under the curve = 0.97, 95% confidence interval = 0.91-1.00, according to naïve Bayes). CONCLUSION: Apical right ventricular strain as well as right atrial strain provides complementary information, both critical to predict acute-right ventricular failure and chronic-right ventricular failure, respectively.

Mechanical antithrombogenic properties by vibrational excitation of the impeller in a magnetically levitated centrifugal blood pump.

Mechanical circulatory support devices have been used clinically for patients with heart failure for over 10 years. However, thrombus formation inside blood pumps remains a risk to patient life, causing pump failure and contributing to neurological damage through embolization. In this article, we propose a method for preventing thrombus formation by applying vibrational excitation to the impeller. We evaluate the ability of this method to enhance the antithrombogenic properties of a magnetically levitated centrifugal blood pump and ensure that the impeller vibration does not cause undue hemolysis. First, 3 vibrational conditions were compared using an isolated pump without a mock circulation loop; the vibrational excitation frequencies and amplitudes for the impeller were set to (a) 0 Hz-0 µm, (b) 70 Hz-10 µm, and (c) 300 Hz-2.5 µm. The motor torque was measured to detect thrombus formation and obtain blood coagulation time by calculating the derivative of the torque. Upon thrombus detection, the pump was stopped and thrombi size were evaluated. The results showed an increase in the blood coagulation time and a decrease in the rate of thrombus formation in pumps with the impeller vibration. Second, an in vitro hemolysis test was performed for each vibrational condition to determine the effect of impeller vibration on hemolysis. The results revealed that there was no significant difference in hemolysis levels between each condition. Finally, the selected vibration based on the above test results and the non-vibration as control were compared to investigate antithrombogenic properties under the continuous flow condition. The blood coagulation time and thrombi size were investigated. As a result, vibrational excitation of the impeller at a frequency of 300 Hz and amplitude of 2.5 µm was found to significantly lengthen clotting time, decreasing the rate of pump thrombus compared to the non-vibration condition. We indicate the potential of impeller vibration as a novel mechanical antithrombogenic mechanism for rotary blood pumps.

Right ventricular failure following left ventricular assist device implantation is associated with a preoperative pro-inflammatory response.

BACKGROUND: Systemic inflammation during implant of a durable left ventricular assist device (LVAD) may contribute to adverse outcomes. We investigated the association of the preoperative inflammatory markers with subsequent right ventricular failure (RVF). MATERIALS AND METHODS: Prospective data was collected on 489 patients from 2003 through 2017 who underwent implantation of a durable LVAD. Uni- and multivariable correlation with leukocytosis was determined using linear and binary logistic regression. The population was also separated into low (< 10.5 K/ul, n = 362) and high (> 10.5 K/ul, n = 127) white blood cell count (WBC) groups. Mantel-Cox statistics was used to analyze survival data. RESULTS: Postop RVF was associated with a higher preop WBC (11.3 + 5.7 vs 8.7 + 3.1) and C-reactive protein (CRP, 5.6 + 4.4 vs 3.3 + 4.7) levels. Multivariable analysis identified an independent association between increased WBC preoperatively with increased lactate dehydrogenase (LDH, P < 0.001), heart rate (P < 0.001), CRP (P = 0.006), creatinine (P = 0.048), and INR (P = 0.049). The high WBC group was more likely to be on preoperative temporary circulatory support (17.3% vs 6.4%, P < 0.001) with a trend towards greater use of an intra-aortic balloon pump (55.9% vs 47.2%, P = 0.093). The high WBC group had poorer mid-term survival (P = 0.042). CONCLUSIONS: Postop RVF is associated with a preoperative pro-inflammatory environment. This may be secondary to the increased systemic stress of decompensated heart failure. Systemic inflammation in the decompensated heart failure may contribute to RVF after LVAD implant.

The Effect of LVAD Pressure Sensitivity on the Assisted Circulation Under Consideration of a Mitral Insufficiency: An In Vitro Study.

Current left ventricular assist devices (LVADs) differ with respect to their pump characteristics as described by the pump characteristic curve (also called HQ-curve). Pressure sensitive LVADs depict a flat characteristic curve while most available LVADs have a steep, less pressure sensitive characteristic curve. This in vitro study investigated the effect of LVAD pressure sensitivity with a focus on the afterload of the right ventricle (RV) which is one out of many factors influencing right heart failure (RHF). To this end, two laboratory pumps differing in pressure sensitivity were tested as LVAD in an established, active mock circulation loop (MCL). The MCL represented patients with left heart failure and mitral insufficiency as another contributing factor to RV afterload. The results show that the pressure-volume loop (PV-loop) of the left ventricle (LV) undergoes a leftward and thus somewhat of a downward-shift for highly pressure sensitive support. Consequently, the LV is unloaded to a higher degree at comparable arterial blood pressure and identical cardiac output, pulmonary and systemic vascular resistance and ventricular contractility. This causes a concomitant decrease of RV afterload. This effect seems to be due to increased unloading during systole. In case of a severe concomitant mitral insufficiency and looking at left atrial pressure, the difference is 18.5%. Without mitral insufficiency, the difference is reduced to 10.2%.

Video capsule endoscopy is safe and effective in suspected small bowel bleeding among left ventricular assist device recipients.

INTRODUCTION:: Suspected small bowel bleeding is frequently encountered in left ventricular assist device recipients and the identification of the culprit lesion may be challenging. Data regarding the safety and yield of small bowel capsule in the investigation of suspected small bowel bleeding are limited. We aimed to evaluate the safety and efficacy of small bowel video capsule endoscopy for the investigation of suspected small bowel bleeding among left ventricular assist device recipients. METHODS:: Patients with left ventricular assist device who underwent video capsule endoscopy for the investigation of suspected small bowel bleeding were identified. Suspected small bowel bleeding was defined as the presence of overt bleeding at least 30 days following left ventricular assist device implantation with no identifiable cause in upper and lower endoscopy. RESULTS:: A total of 10 patients with left ventricular assist device associated suspected small bowel bleeding performed 12 small bowel capsule endoscopies between January 2008 and December 2015 at our tertiary medical care facility. There were no cases of capsule retention or any other serious adverse events during the exams. A significant finding was identified in 8 out of 10 patients, including 3 cases of small bowel angioectasia, 2 cases of small bowel ulcers, 1 case of cecal polyp, and 2 cases of active bleeding with no apparent bleeding source. Small bowel enteroscopy identified and treated bleeding angioectasia in the latter two cases. CONCLUSION:: Small bowel capsule endoscopy is safe and effective in the investigation of left ventricular assist device associated suspected small bowel bleeding.

Accurate Method of Quantification of Aortic Insufficiency During Left Ventricular Assist Device Support by Thermodilution Analysis: Proof of Concept and Validation by a Mock Circulatory System.

Aortic insufficiency (AI) is an intractable complication during long term left ventricular assist device (LVAD) support. Conventional evaluation of AI depends on ultrasound evaluation, which is mainly a qualitative, not a quantitative method. The pathophysiology of AI during LVAD is shunt formation. Conversely, the methods to quantify the shunt of congenital heart disease are already established, and among these is the thermodilution technique. To develop an accurate quantification method for AI (namely, a shunt), we have adopted this conventional thermodilution technique. The purpose of this study was to determine whether this technique could calculate the shunt magnitude accurately in a simulated cardiac circuit. The magnitude of AI was represented by the recirculation rate (RR), defined by regurgitant flow (RF) divided by pump flow (PF). A mock circulatory system for an LVAD endurance test (Laboheart NCVC; Iwaki & Co., Ltd, Tokyo, Japan) was used. A centrifugal LVAD was equipped in the Laboheart in parallel from the left ventricle to the aorta. A parallel shunt circuit was created across the aortic valve to mimic AI. To control the magnitude of AI, the resistance of the AI circuit was changed. Heart failure was simulated by controlling the parameters of the Laboheart. The LVAD was driven in full bypass condition, confirming that the heart did not eject forward flow via the aortic valve. PF, RF, and the temperatures of two points of the outflow graft measured with two thermistors were monitored. Analyses were started after confirming that circuit water temperature was the same as room temperature. Hot water was injected from a port between the two thermistors of the outflow conduit. The time-temperature curves of both thermistors were recorded, and RR was calculated. Two values of RR calculated in two different ways (by analyzing thermistors and by calculating from flowmeter values) were compared. Multiple measurements were done by changing the magnitude of AI. The existence of AI could be easily confirmed by analyzing the temperature data. There was a good correlation between RR by thermistor and RR by flowmeter data (r = 0.984). Furthermore, the two RR values were almost the same. This novel technique could provide an accurate method for quantifying AI during LVAD support. This method can be clinically applied by left-sided cardiac catheterization if a dedicated catheter with two thermistors and an injection hole is developed.

Mechanical circulatory support in patients with cardiogenic shock in intensive care units: A position paper of the "Unité de Soins Intensifs de Cardiologie" group of the French Society of Cardiology, endorsed by the "Groupe Athérome et Cardiologie Interventionnelle" of the French Society of Cardiology.

Cardiogenic shock (CS) is a major challenge in contemporary cardiology. Despite a better understanding of the pathophysiology of CS, its management has only improved slightly. The prevalence of CS has remained stable over the past decade, but its outcome has seen few improvements, with the 1-month mortality rate still in the range of 40-60%. Inotropes and vasopressors are the first-line therapies for CS, but they are associated with significant hazards, and have well-known deleterious effects. Furthermore, a significant number of patients develop refractory CS with haemodynamic instability, causing critical organ hypoperfusion and/or pulmonary congestion, despite increasing doses of catecholamines. A major change has resulted from the recent advent and availability of potent mechanical circulatory support (MCS) devices. These devices, which ensure sustained blood flow, provide a great and long-awaited opportunity to improve the prognosis of CS. Several efficient MCS devices are now available, including left ventricle-to-aorta circulatory support devices and full pulmonary and circulatory support with venoarterial extracorporeal membrane oxygenation. However, evidence to support their indications, the timing of implantation and the selection of patients and devices is scarce. Because these devices are gaining momentum and are becoming readily available, the "Unité de Soins Intensifs de Cardiologie" group of the French Society of Cardiology aims to propose practical algorithms for the use of these devices, to help intensive care unit and cardiac care unit physicians in this complex area, where evidence is limited.

Bloodstream infections in mechanical circulatory support device recipients in the International Society of Heart and Lung Transplantation Mechanically Assisted Circulation Support Registry: Epidemiology, risk factors, and mortality.

BACKGROUND: We used multicenter international data from the International Society of Heart and Lung Transplantation Mechanically Assisted Circulation Support (IMACS) registry to determine bloodstream infection (BSI) event rate, independent risk factors, and association with mortality. METHODS: Included were patients registered in IMACS from January 2013 through December 2015, assessed BSI event rate of mechanical circulatory support (MCS) and non-MCS-related BSIs, and conducted univariate and multivariate analyses between BSI with baseline characteristics and mortality. RESULTS: We documented 1,606 BSIs in 1,231 of 10,171 MCS recipients (12%), with an event rate of 2.43 BSIs/100 patient-months within 3 months after implant (early onset) and 1.03 BSIs/100 patient-months after 3 months (late onset). Of these episodes, 1,378 (85.8%) were non- MCS-related BSI. Increasing body mass index and bilirubin were independent correlates of MCS-related BSI. Independent correlates of non-MCS-related BSI included older age, higher body mass index, previous cardiac surgery, baseline chronic renal disease and dialysis, pre-implant frailty, presence of biventricular assist device, total artificial heart or right ventricular assist device, and Interagency Registry for Mechanically Assisted Circulatory Support category 1. Survival after 3 months after implant of patients who developed early-onset BSI was 56.9% at 24 months vs 77.4% in patients without early-onset BSI (p < 0.001). Early-onset BSI was an independent correlate of mortality at 3 months after implantation (hazard ratio, 2.56; 95% confidence interval, 2.09-3.15; p < 0.001). CONCLUSIONS: Early-onset BSI was associated with significantly increased 24-month mortality. More than 85% of these BSIs were not device related. There is an opportunity for infection prevention practices to decrease the BSI event rate, which may affect 24-month survival. These data can also serve as benchmarking for individual institutions.

Importance of stratifying acute kidney injury in cardiogenic shock resuscitated with mechanical circulatory support therapy.

OBJECTIVE: Although the outcomes of patients with cardiogenic shock remain poor, short-term mechanical circulatory support has become an increasingly popular modality for hemodynamic assistance and organ preservation. Because the kidney is exquisitely sensitive to poor perfusion, acute kidney injury is a common sequela of cardiogenic shock. This study examines the incidence and clinical impact of acute kidney injury in patients with short-term mechanical circulatory support for cardiogenic shock. METHODS: Retrospective review was performed of 293 consecutive patients with cardiogenic shock who were treated with short-term mechanical circulatory support. The well-validated 2014 Kidney Disease Improving Global Outcomes criteria were used to stage acute kidney injury. Outcomes of interest were long-term mortality and renal recovery. RESULTS: Acute kidney injury developed in 177 of 293 patients (60.4%), of whom 113 (38.6%) were classified with stage 3 (severe). Kaplan-Meier survival estimates indicated a 1-year survival of 49.2% in the nonsevere (stages 0-2) acute kidney injury cohort versus 27.3% in the severe acute kidney injury cohort (P < .001). Multivariable Cox regression demonstrated that severe acute kidney injury was a predictor of long-term mortality (hazard ratio, 1.54; confidence interval, 1.10-2.14; P = .011). Among hospital survivors, renal recovery occurred more frequently (82.4% vs 63.2%, P = .069) and more quickly (5.6 vs 24.5 days, P < .0001) in the nonsevere than in the severe acute kidney injury group. CONCLUSIONS: Acute kidney injury is common and frequently severe in patients in cardiogenic shock treated with short-term mechanical circulatory support. Milder acute kidney injury resolves with survival comparable to patients without acute kidney injury. Severe acute kidney injury is an independent predictor of long-term mortality. Nonetheless, many surviving patients with acute kidney injury do experience gradual renal recovery.