For patients with low pretest probability, the guidelines recommended the D-dimer test as the best first step. Further testing isn’t needed when the D-dimer is negative, noted Dr. Lim, a hematologist and professor at McMaster University, Hamilton, Ont.
The guidelines also recommended using ventilation-perfusion scintigraphy (V/Q scan) for imaging a pulmonary embolism over a CT scan, which uses more radiation. But V/Q scans are not ideal for assessing older patients or patients with lung disease, Dr. Lim cautioned.
Management
Management of VTE should occur, when feasible, through a specialized anticoagulation management service center, which can provide care that is best suited to the complexities of anticoagulation therapy. But it’s a level of care that many U.S. patients don’t currently receive and hence is an area ripe for growth, said Daniel M. Witt, PharmD, professor and vice-chair of pharmacotherapy at the University of Utah, Salt Lake City.
CDC/Janice Carr
This scanning electron micrograph (SEM) depicted a closer view of a number of red blood cells found enmeshed in a fibrinous matrix on the luminal surface of an indwelling vascular catheter; Magnified 7766x.
The guidelines recommended against bridging therapy with LMWH for most patients who need to stop warfarin when undergoing an invasive procedure. The guidelines also called for “thoughtful” use of anticoagulant reversal agents and advised that patients who survive a major bleed while on anticoagulation should often resume the anticoagulant once they are stabilized.
For patients who develop heparin-induced thrombocytopenia, the 4Ts score is the best way to make a more accurate diagnosis and boost the prospects for recovery, said Dr. Cuker (Blood. 2012 Nov 15;120[20]:4160-7). The guidelines cite several agents now available to treat this common complication, which affects about 1% of the 12 million Americans treated with heparin annually: argatroban, bivalirudin, danaparoid, fondaparinux, apixaban, dabigatran, edoxaban, and rivaroxaban.
ASH has a VTE website with links to detailed information for each of the guideline subcategories: prophylaxis in medical patients, diagnosis, therapy, heparin-induced thrombocytopenia, VTE in pregnancy, and VTE in children. The website indicates that additional guidelines will soon be released on managing VTE in patients with cancer, in patients with thrombophilia, and for prophylaxis in surgical patients, as well as further information on treatment. A spokesperson for ASH said that these additional documents will post sometime in 2019.
At the time of the release, the guidelines panel published six articles in the journal Blood Advances that detailed the guidelines and their documentation.
The articles include prophylaxis of medical patients (Blood Advances. 2018 Nov 27;2[22]:3198-225), diagnosis (Blood Advances. 2018 Nov 27;2[22]:3226-56), anticoagulation therapy (Blood Advances. 2018 Nov 27;2[22]:3257-91), pediatrics (Blood Advances. 2018 Nov 27;2[22]:3292-316), pregnancy (Blood Advances. 2018 Nov 27;2[22]:3317-59), and heparin-induced thrombocytopenia (Blood Advances. 2018 Nov 27;2[22]:3360-92).
Dr. Cushman, Dr. Lim, and Dr. Witt reported having no relevant disclosures. Dr. Cuker reported receiving research support from T2 Biosystems.