Evaluation of Vasoactive-Inotropic Score and Survival to Decannulation in Adult Patients on Venoarterial Extracorporeal Life Support: An Observational Cohort Study.

Extracorporeal life support with venoarterial extracorporeal membrane oxygenation (VA-ECMO) is used to assist circulation in patients with severe cardiogenic shock or cardiac arrest. The vasoactive-inotropic score (VIS) is a standardized calculation of vasoactive medication support which uses coefficients for each medication that converts them to an equivalent value. The purpose of this study was to assess the VIS as an early prognostication tool for survival to decannulation patients on adult VA-ECMO support. This was a single-center, observational cohort study of adult patients who received VA-ECMO support compared based on their survival to decannulation. The primary endpoint was the VIS at hour 24 postcannulation. Among the 265 patients included in this study, 140 patients (52.8%) survived to decannulation of VA-ECMO. At 24 hours postcannulation, a lower VIS was observed in the group that survived decannulation (6.5 ± 7.5 vs. 12.3 ± 16.9; p < 0.001). Multivariate analysis performed also demonstrates an association between 24-hour VIS and survival to decannulation (odds ratio 0.95; 95% confidence interval, 0.91-0.95). This study suggests that the 24-hour VIS may be an early prognostic indicator in patients on VA-ECMO patients. http://links.lww.com/ASAIO/B39.

Risk of pump thrombosis and stroke in patients with continuous-flow left ventricular assist devices and gastrointestinal bleeding.

Gastrointestinal (GI) bleeding is a common complication following the placement of continuous-flow left ventricular assist devices (LVADs) in patients with advanced heart failure. Secondary events arising as a result of GI bleeding have not been well-described. Furthermore, attribution of these events to bleeding is complicated by the interruption or de-intensification of antithrombotic therapy, while bleeding is controlled. The purpose of this study was to assess the incidence of pump thrombosis and ischemic stroke in patients with LVADs who experience GI bleeding, while on support. This was a single-center, retrospective, observational cohort study of consecutive patients with LVADs implanted from January 2012 to June 2018. Patients were assigned to comparator groups based on whether they experienced GI bleeding while on LVAD support. The primary endpoint assessed was the composite of pump thrombosis or ischemic stroke. Secondary endpoints assessed included incidence of pump thrombosis or ischemic stroke. A total of 250 patients were included after screening for exclusion criteria, 101 (40.4%) in the GI bleeding group, and 149 (59.6%) in the non-bleeding group. The incidence of pump thrombosis or ischemic stroke was not significantly greater in patients experiencing GI bleeding [23 (22.8%) vs. 21 (14.1%); P = .09]; however, the incidence of ischemic stroke alone was significantly greater [17 (16.8%) vs. 10 (6.7%); P = .01]. We conclude that GI bleeding in LVAD patients may be associated with a greater risk of ischemic stroke.

Anticoagulation of Impella with a Bivalirudin Purge Solution.

The use of percutaneous ventricular assist devices (VADs) in the acute management of cardiogenic shock is becoming increasingly common. The Impella is a percutaneous VAD, which requires a heparin-containing purge solution to prevent thrombosis and maintain proper pump functionality. In this report, we describe two patients with heparin-induced thrombocytopenia (HIT) supported with an Impella using a bivalirudin-containing purge solution. Case 1 involved a 39-year-old man with cardiogenic shock, initially implanted with an intraaortic balloon pump, who developed HIT early in his hospital course. His worsening hemodynamics necessitated the placement of an Impella and later venoarterial extracorporeal membrane oxygenation until he eventually underwent durable left VAD implantation. Case 2 involved a 69-year-old man who had an Impella implanted for worsening cardiogenic shock. HIT was suspected shortly after device insertion, necessitating switching his anticoagulation to bivalirudin. He was successfully bridged directly to heart transplantation. Both patients' courses resulted in therapeutic anticoagulation without major bleeding or thrombotic events. These cases demonstrate the safe and effective use of bivalirudin-containing purge solutions for patients with confirmed HIT requiring temporary mechanical circulatory support with Impella.

The role of pharmacotherapy in the prevention of sudden cardiac death in patients with heart failure.

Sudden cardiac death remains a significant threat to the survival of patients with heart failure. Long-term cardiac remodeling predisposes these patients to develop malignant ventricular arrhythmias. Permanent implantable and temporary external defibrillators remain a mainstay for the prevention of sudden cardiac death in this population. For decades, researchers have attempted to identify reliable drug therapies to avoid such arrhythmias; however, to date, success has been inconsistent. This review aims to explore the evidence defining the role of drug therapies for direct and indirect suppression of arrhythmias that may cause sudden cardiac death in patients with heart failure.

Antiplatelet Therapy Considerations in Ischemic Cardiogenic Shock: Implications of Metabolic Bioactivation.

Dual antiplatelet therapy with aspirin and a P2Y12 receptor antagonist remains a mainstay in the prevention of ischemic events following coronary stent placement. Significant controversy exists regarding the optimal management of high platelet reactivity despite antiplatelet therapy; however this finding has been consistently associated with poor clinical outcomes including greater risk of stent thrombosis and myocardial infarction. Variability in antiplatelet effects of clopidogrel and prasugrel has been linked to genetic polymorphisms and potential drug-drug interactions. Both of these factors have significant influence on the cytochrome P-450 enzyme system activity of the liver responsible for their biotransformation to the active form of both drugs. Very little has been publicized regarding differences in antiplatelet effects which may be associated with conditions in which the functional capacity of the liver may be temporarily compromised. Patients who present with cardiogenic shock due to acute coronary syndromes have evidence of multiorgan dysfunction including liver dysfunction that may affect the activity of these drugs. This review aims to explore existing evidence and propose additional considerations to the selection of antiplatelet therapy in patients with cardiogenic shock who receive catheter-based revascularization and stent placement.

Effectiveness of protocol guided heparin anticoagulation in patients with the TandemHeart percutaneous ventricular assist device.

The purpose of this analysis is to assess the effectiveness of heparin anticoagulation in cardiogenic shock patients with TandemHeart percutaneous ventricular assist device support for which the institution's TandemHeart heparin protocol was implemented compared to those managed without protocol. This retrospective analysis included 15 patients in the protocol group and 10 patients in the nonprotocol group. Patients in the protocol group had a higher percentage of therapeutic activated partial thromboplastin time (aPTT) and lower percentage of supra-therapeutic aPTT values compared to the nonprotocol group. We conclude that TandemHeart anticoagulation may be more effectively managed through the use of a protocol than without any protocol.

Thrombosis in continuous-flow left ventricular assist devices: pathophysiology, prevention, and pharmacologic management.

Continuous-flow left ventricular assist devices reduce short-term mortality and improve quality of life in patients with end-stage heart failure. Unfortunately, device-related complications remain common, with many patients experiencing adverse events within the first year. New literature suggests that rates of device-related thrombosis may be increasing since 2011, which is particularly troublesome given that this pathology can result in a disabling stroke, organ damage, and death. In 2013, a group of practitioners in the field of mechanical circulatory support published a treatment algorithm based on their expert opinion. However, a comprehensive review of the pharmacotherapy of this condition is lacking. A search of the literature revealed 20 separate publications of case reports or case series describing outcomes associated with the use of drug therapy for suspected pump thrombosis. Each of these experiences was limited by small sample size, nonrandomized treatment allocation, and nonstandardized medication dosing. Data describing the outcomes of surgical versus medical management of device thrombosis are also sparse, with only three published reports identified. Based on the review of this limited literature, surgical management appears to be the preferred treatment modality, especially in those with organ hypoperfusion or hemodynamic instability. In patients ineligible for surgery, pharmacotherapy options remain limited. Use of all drug classes described in the literature for the HeartMate II device-fibrinolytics, glycoprotein IIb/IIIa inhibitors, and direct thrombin inhibitors-was hindered by either marginal efficacy or bleeding. Based on historical experience with unfractionated heparin in patients under HeartMate II support, we recommend this agent as a possible option for those with suspected pump thrombosis in lieu of surgical device exchange. For the HeartWare HVAD, limited data suggest that direct intraventricular administration of alteplase may be an acceptable treatment alternative. Additional research is clearly needed to further delineate the role of pharmacotherapy and to identify the optimal agent for managing this potentially life-threatening condition.

How do we manage cardiopulmonary bypass coagulopathy?

BACKGROUND: Patients who undergo cardiopulmonary bypass (CPB) are at risk for coagulopathy. Suboptimal turnaround time (TAT) of laboratory coagulation testing results in empiric administration of blood products to treat massive bleeding. We describe our initiative in establishing the coagulation-based hemotherapy (CBH) service, a clinical pathology consultation service that uses rapid TAT coagulation testing and provides comprehensive assessment of bleeding in patients undergoing CPB. A transfusion algorithm that treats the underlying cause of coagulopathy was developed. STUDY DESIGN AND METHODS: The coagulation testing menu includes all aspects of coagulopathy with close proximity of the laboratory to the operating room to allow for rapid test results. The hemotherapy pathologist monitors laboratory results at several stages in surgery and uses a comprehensive algorithm to monitor a patient's hemostasis. The optimal number and type of blood products are selected when the patient is taken off CPB. RESULTS: The CBH service was consulted for 44 ventricular assist device implants, 30 heart transplants, and 31 other cardiovascular surgeries from May 2012 through November 2013. The TAT for laboratory tests was 15 minutes for complete blood count, antithrombin, and coagulation panel and 30 minutes for VerifyNow and thromboelastography, in comparison to 45 to 60 minutes in normal settings. The transfusion algorithms were used with optimal administration of blood components with preliminary data suggestive of reduced blood product usage and better patient outcomes. CONCLUSION: We described the successful introduction of a novel pathology consultation service that uses a rapid TAT coagulation testing menu with transfusion algorithms for improved management of CPB patients.

Chemical and physical compatibility of an intravenous solution of epinephrine with calcium chloride.

An infusion of epinephrine combined with calcium chloride has been used historically as an intravenous inotropic solution to support critically ill heart failure patients with severe cardiogenic shock. There is no reliable data on the stability of this solution beyond three hours. This study was conducted to evaluate the chemical and physical compatibility of epinephrine (0.032 mg/mL) combined with calcium chloride (4 mg/mL) in a solution for intravenous administration up to 26 hours at room temperature. The chemical stability of epinephrine was monitored by measuring epinephrine concentrations using high-performance liquid chromatography. The physical compatibility of the mixture was determined by measuring spectrophotometric absorbance between 400 to 700 nm. Absorbance greater than 0.010 AU was considered an indicator of the presence of precipitation. The results showed epinephrine with calcium chloride was stable together in normal saline up to 26 hours at room temperature, irrespective of exposure to light. The absorbance of epinephrine throughout the study was less than 0.010 AU, indicating no significant precipitation. Conclusions indicate that epinephrine (0.032 mg/mL) combined with calcium chloride (4 mg/mL) in normal saline at room temperature is acceptably stable up to 26 hours for intravenous administration.

Mobile computing platform with decision support modules for hemotherapy.

OBJECTIVES: We describe the development of a mobile computing platform (MCP) with a decision support module (DSM) for patients in our coagulation-based hemotherapy service. METHODS: The core of our MCP consists of a Microsoft Excel spreadsheet template used to gather and compute data on cardiopulmonary bypass (CPB) patients intraoperatively. The DSM is embedded into the Excel file, where the user would enter in laboratory results, and through our 45 embedded algorithms, recommendations for transfusion products would be displayed in the Excel file. RESULTS: The DSM has helped decrease the time it takes to come to a transfusion recommendation, helps double-check recommendations, and is an excellent tool for teaching. Furthermore, the problems that occur with a paper system have been eliminated, and we are now able to access this information easily and reliably. CONCLUSIONS: The development and implementation of our MCP system has greatly increased the productivity and efficiency of our hemotherapy service.

Managing new oral anticoagulants in the intensive care unit.

Warfarin has been the mainstay of oral anticoagulation for more than half a century. Within the last several years, 2 new classes of oral anticoagulants have been introduced as potential alternatives to warfarin for certain indications. The oral direct thrombin inhibitor, dabigatran, and 2 factor Xa inhibitors, rivaroxaban and apixaban, are the newest agents approved for use in the United States. These agents have been studied in various areas including stroke prophylaxis in atrial fibrillation, prevention and treatment of venous thromboembolism, and for reduction of ischemic events following acute coronary syndromes. While these agents do not require routine monitoring of international normalized ratio, these agents may be more challenging to reverse than traditional warfarin therapy. The following review will focus on describing the areas where the new oral anticoagulant agents have been studied, the basic pharmacologic characteristics of each agent, and how to appropriately manage the reversal of these agents when indicated.

Evaluation of bivalirudin hyper- and hypo-ACT responses in the setting of percutaneous coronary intervention.

BACKGROUND: Bivalirudin has emerged as a suitable alternative anticoagulant to unfractionated heparin and low-molecular-weight heparins during percutaneous coronary intervention (PCI) procedures in the management of coronary artery disease and acute coronary syndromes (ACS). In clinical trials, bivalirudin dosing was standardized, and activated clotting time (ACT) did not influence dosing adjustments. The role of ACT monitoring of bivalirudin in PCI is not defined based on current practice guidelines. HYPOTHESIS: The hypothesis of this study is that hyper- and hypo-ACT responses to bivalirudin in PCI may be associated with excessive bleeding or thrombotic complications. METHODS: The planned protocol screened all patients who received bivalirudin therapy and ACT monitoring during PCI in a single center's cardiac catheterization laboratory from July 2009 to June 2010. The first ACT monitored 5 to 60 minutes after bivalirudin initiation was screened for inclusion. Values above 800 seconds and below 300 seconds were included as hyper- and hypo-ACT responses, respectively. Outcomes assessed include thrombotic and bleeding complications. RESULTS: There were 32 patients identified as hyper-responders and 20 patients identified as hypo-responders. There were no significant thrombotic or bleeding complications in the hyper-responder group. There was 1 case (1/20, 5%) of angiographically confirmed acute stent thrombosis immediately following the placement of 5 adjoining bare-metal stents in the right coronary artery of a hypo-responder. CONCLUSIONS: Hyper-ACT responses to bivalirudin therapy in PCI were not associated with additional bleeding risk. Bivalirudin may not adequately protect hypo-ACT responders against thrombotic complications during PCI.