We present a case of multi-territorial ischemic strokes in the setting of restrictive cardiomyopathy secondary to idiopathic hypereosinophilia.

Hypereosinophilic syndrome (HES) is a rare cause of stroke. It can lead to prothrombotic states and cardiac involvement can increase the risk of cardioembolic strokes. Treatment differs from regular stroke management.

Case Report

A 69-year-old right-handed female with history of Factor V Leiden mutation and chronic eosinophilia of unknown etiology, initially presented with chest pain, tachycardia, and elevated troponins (9.38ng/ml). After an unrevealing cardiac catheterization, patient developed acute disorientation, expressive aphasia, and tetraparesis characterized by paralysis of proximal muscles with mild paresis of distal interossei and plantar-dorsiflexors, bilaterally. Brain Magnetic Resonance Imaging (MRI) revealed numerous small infratentorial and bihemispheric supratentorial acute ischemic infarcts. Vessel imaging was unremarkable, and telemetry was negative throughout the hospitalization. Remainder of stroke workup was unrevealing, including a negative TTE and subsequent TEE. Due to clinical suspicion of embolic source despite the absence of clinical findings,  a cardiac MRI was obtained revealing diffuse subendocardial resting hypoperfusion with subendocardial fibrosis associated with apical hypokinesis and filling defect consistent with thrombi. Loeffler’s endocarditis was diagnosed in the setting of values of WBC (49.1 x10^3/mcL) and eosinophils (44.1%) at admission. Patient was treated with systemic anticoagulation with heparin drip (PTT 40-60) and bridged to Warfarin (INR goal 2-3). Patient received high dose steroids followed by a taper and was started on anti-IL 5 for long term management. Serial serum tests showed down-trending eosinophil counts.

Case reports of ischemic strokes occurring in the setting of Loeffler endocarditis are scarce and is likely to be an overlooked cause, even in those with diagnosis of hypereosinophilia. Management consists in high-dose steroids and anticoagulants when an intracardiac thrombus is found. Long term, Monoclonal antibodies targeting IL-5 can be used to reduce the eosinophilic count.