The inferior and lat- eral walls of the LV from the midcavity to the apex are most commonly involved by this process.547 Among cohorts of patients with cardiac disease, the esti- mated prevalence of LV noncompaction varies from 0.9% by echocardiographic criteria to 9.8% with car- diac magnetic resonance criteria.548 LV noncompac- tion has a broad spectrum of clinical manifestations, ranging from asymptomatic state to severe heart failure, ventricular arrhythmias, and thromboembolic The risk of thromboembolism in LV noncompaction cardiomyopathy has been evaluated in several case series, which have reported an up to 24% risk of cerebral embolism at follow-up.534,549 This increased risk has been theorized to result from blood stasis within the prominent LV trabecula- tions and intertrabecular recesses.533 535 Given the shared pathophysiological basis with LV endocavi- tary thrombus, we make this recommendation. 4. There are 5 randomized trials evaluating the effects of antithrombotic therapy on clinical out- comes, including strokes, in patients with heart failure and reduced LV EF in sinus rhythm.524 528 The WARCEF trial (Warfarin vs. Aspirin in Reduced Cardiac Ejection Fraction) documented no ben- efit of warfarin therapy compared with acetyl- salicylic acid at a mean follow-up of 3.5 years for the primary outcome (death, ischemic stroke, or although patients on warfarin had reduced incidence of stroke, par- ticularly patients with an EF 15%,550 The more recent COMMANDER HF trial (A Study to Assess the Effectiveness and Safety of Rivaroxaban in Reducing the Risk of Death, Myocardial Infarction or Stroke in Participants With Heart Failure and Coronary Artery Disease Following an Episode of Decompensated Heart Failure) randomized a total of 5022 patients with chronic heart failure, an EF of 40%, coronary artery disease, and elevated plasma natriuretic peptides to rivaroxaban 2.5 mg twice daily or placebo.528 After a median follow-up of 21.1 months, the primary end point (death, MI, or stroke) occurred in 25.0% of patients assigned to rivaroxaban versus 26.2% of those receiving pla- cebo. 