AHA scientific statement offers guidance on LV thrombus

A new scientific statement from the American Heart Association offered suggestions for managing patients at risk for left ventricular (LV) thrombus and those with the condition.

A writing committee developed the statement after a search of the literature and addressed eight key clinical management questions related to LV thrombus. Suggestions for management are as follows:

• Cardiac magnetic resonance imaging may be most appropriate when an echocardiogram suggests LV thrombus but is not diagnostic even with ultrasound enhancement, as well as when echocardiography does not demonstrate LV thrombus but there is still clinical concern.
• Clinicians should treat patients with LV thrombus after myocardial infarction using oral anticoagulants (OACs), typically for three months. This suggestion is based on reasonable study data.
• Given the relatively weak data supporting prophylactic OACs in patients with acute anteroapical ST-segment elevation myocardial infarction (STEMI) treated with reperfusion therapy and anteroapical akinesis, clinicians considering OAC should take the perceived risks of thrombus formation and bleeding into account and engage in shared decision making. If OAC is started, treatment duration might be one to three months, depending on bleeding risk, the statement said.
• Patients with dilated cardiomyopathy should not receive prophylactic OAC, with the possible exception of those with specific cardiomyopathies, such as eosinophilic myocarditis, where associated factors increase LV thrombus risk. In these cases, clinicians may consider OAC. These suggestions are based on reasonable randomized data.
• Clinicians should treat patients with nonischemic cardiomyopathy and LV thrombus with OAC for at least three to six months. Therapy can be discontinued if the LV ejection fraction improves to more than 35% with resolution of the LV thrombus or if major bleeding develops. These suggestions are based on limited data. Data are insufficient to determine whether to continue OAC indefinitely, the statement said.
• It may be prudent to treat patients with OAC for newly diagnosed mural (laminated) LV thrombus in the same way as a patient with a protruding or mobile thrombus. This suggestion is based on limited data.
• A direct-acting oral anticoagulant (DOAC) seems to be a reasonable alternative to warfarin in patients with LV thrombus. This suggestion is based on supportive but insufficiently powered randomized data.
• A trial of an alternative OAC or low-molecular-weight heparin is not unreasonable in some patients with persistent LV thrombus; however, it is also not unreasonable to discontinue OAC in patients with persistent mural thrombus, particularly if it becomes organized or calcified. Both of these suggestions are based on consensus opinion.

All but one of the reviewed studies addressed full-dose anticoagulation, and the suggested management strategies should not be extrapolated to low-dose DOACs, the authors said. They noted that data to make informed treatment recommendations about LV thrombus are often insufficient and called for additional research in several areas, including the optimal anticoagulants for specific clinical settings and whether indefinite anticoagulation is merited in patients with dilated cardiomyopathy or previous MI who develop LV thrombus. The scientific statement was published Sept. 15 by Circulation.