Comparison of Outcomes in Patients Requiring Mechanical Circulatory Support Who Received Cangrelor in Addition to Anticoagulation Versus Anticoagulation Alone.

OBJECTIVES: To evaluate the safety of cangrelor administered concurrently with heparin or bivalirudin in patients on mechanical circulatory support. DESIGN: A single-center, retrospective cohort study of adult patients consecutively admitted between January 2016 and October 2020. SETTING: A tertiary medical center. PARTICIPANTS: Adult patients admitted to the cardiovascular intensive care unit put on mechanical circulatory support for acute myocardial infarction (AMI) or non-AMI indications. Patients who received cangrelor underwent percutaneous coronary intervention with stenting during the index event or within the last year. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The primary outcome was the incidence of major bleeding, defined by the Extracorporeal Life Support Organization criteria, in patients with mechanical circulatory support receiving cangrelor plus anticoagulation with heparin or bivalirudin with or without aspirin versus patients who did not receive cangrelor. Sixty-eight patients were included in the study. Twenty-nine patients received cangrelor, and 39 did not. Cangrelor was not associated with an increase in major bleeding; however, the CI was wide (adjusted hazard ratio 1.93, 95% CI 0.61-6.11; p = 0.262). CONCLUSIONS: Patients receiving cangrelor did not appear to be at higher risk of major bleeding compared to patients not receiving cangrelor. Larger trials should be conducted to better evaluate the safety of cangrelor in patients with mechanical circulatory support.

Heparin Monitoring with an Anti-Xa Protocol Compared to Activated Clotting Time in Patients on Temporary Mechanical Circulatory Support.

BACKGROUND: Temporary mechanical circulatory support (tMCS) devices are used for patients with severe cardiac or respiratory failure; however, these patients are at high risk for clotting and bleeding. The best method to monitor heparin in these patients has not been established. OBJECTIVE: To determine the risks for bleeding and clotting while monitoring heparin with either anti-Xa or activated clotting time (ACT) in tMCS patients. METHODS: A retrospective cohort study was conducted on tMCS patients who received heparin adjusted according to an anti-Xa or ACT protocol. The primary outcome was incidence of major bleeding. Pertinent secondary outcomes were individual components of the primary outcome, clotting events, and time to therapeutic range. RESULTS: There were 103 patients included in the study: 53 in the ACT group and 50 in the anti-Xa group. Overall, there were 30 (56.6%) patients with major bleeding in the ACT group, compared with 16 (32%) patients in the anti-Xa group (P = 0.017). An anti-Xa-based protocol was associated with a decreased hazard of major bleeding (hazard ratio = 0.388 [0.215-0.701]; P = 0.002) in the univariate analysis. In the multivariable analysis, an anti-Xa protocol remained associated with a significantly lower hazard of bleeding. Findings were similar when broken down into more discrete subgroups of the entire cohort, extracorporeal membrane oxygenation life support (ECMO), and non-ECMO groups. CONCLUSION AND RELEVANCE: Anti-Xa monitoring was associated with a lower hazard of bleeding during tMCS compared to an ACT-based protocol. Further studies should evaluate if anti-Xa monitoring should be preferentially used in tMCS.

Argatroban Versus Bivalirudin in the Treatment of Suspected or Confirmed Heparin-Induced Thrombocytopenia.

BACKGROUND: Argatroban and bivalirudin are direct thrombin inhibitors (DTIs) used for the treatment of heparin-induced thrombocytopenia (HIT). The purpose of this study was to determine whether either agent offered an advantage in efficacy and ability to remain within the targeted therapeutic anticoagulation range. METHODS: This was a single-center, retrospective, observational cohort study at a large academic medical center. The primary efficacy outcome was time to therapeutic anticoagulation, defined as total number of hours to achieve 2 consecutive activated partial thromboplastin time (aPTT) values in goal range. RESULTS: A total of 91 patients were included in the analysis. Average time to initial therapeutic anticoagulation was 4.71 hours and 9.8 hours for the argatroban and bivalirudin groups, respectively (P < .01). CONCLUSIONS: Argatroban may be advantageous compared to bivalirudin in achieving initial therapeutic anticoagulation goals among patients with suspected or confirmed HIT.

Methylene Blue Monotherapy Compared With Combination Therapy With Hydroxocobalamin for the Treatment of Refractory Vasoplegic Syndrome: ARetrospective Cohort Study.

OBJECTIVE: To compare the efficacy of methylene blue with combination therapy with hydroxocobalamin in patients experiencing vasoplegic syndrome after cardiac surgery. DESIGN: Retrospective cohort study. SETTING: Tertiary medical center. PARTICIPANTS: Patients who received methylene blue with or without hydroxocobalamin for refractory vasoplegic syndrome rescue therapy. MEASUREMENTS AND MAIN RESULTS: The primary outcome was 0.the ability to maintain mean arterial pressure (MAP) >60 mmHg beyond 1hour after study drug administration. Other pertinent outcomes included MAP at hours 6, 12, and 24 post-administration; both raw and proportional changes of vasopressor doses from baseline at hours 1, 6, 12, and 24 post-administration; and change in pulmonary artery catheter hemodynamics. Overall, 28 doses were administered in 14 patients in the monotherapy group and 17 doses (10 methylene blue, 7 hydroxocobalamin) were administered in 6 patients in the combination therapy group. There were no differences in ability to maintain MAP at 1hour, with 71% of the monotherapy and 82% of combination therapy patients meeting MAP goals (p = 0.49). Pairwise comparisons demonstrated vasopressor reductions at 6, 12, and 24hours in both groups, but only significant reductions at 1hour were observed in the combination therapy group (-0.06 µg/kg/min; p = 0.003) but not in the monotherapy group (-0.015 µg/kg/min; p = 0.14). CONCLUSION: This is the first study to compare methylene blue monotherapy with combination therapy, which suggests there may be an advantage to combination therapy. Further characterization of ideal dosing, timing, and agent selection should be investigated on a larger scale format.