SCMR 22nd Annual Scientific Sessions
Description of Clinical Presentation:
A 61-year-old Caucasian man with recently diagnosed eosinophilic chronic myelomonocytic leukemia (CMML) presented with fever and dyspnea. He had pallor, leg edema, S4 gallop and leukocytosis (54 × 109/L, with 55% eosinophils). He had no history of travel to the tropics. Echocardiogram showed LVEF 60%, grade 2 diastolic dysfunction and apical LV thickening concerning for a tumor or laminated thrombus or focal hypertrophy. Due to severe thrombocytopenia, he could not undergo endomyocardial biopsy or anticoagulation. Cardiac MRI allowed us to arrive at the diagnosis of Loeffler’s endocarditis (LE). He was treated with high dose dexamethasone and imatinib - his heart failure symptoms improved over the next few weeks.
Diagnostic Techniques and Their Most Important Findings:
Transthoracic echocardiogram showed apical endomyocardial obliteration and ventricular thrombi. Cardiac MR has become a crucial test in establishing the diagnosis and monitoring treatment response in LE. CMR images showed complete obliteration of the apex with a mass isointense to that of myocardium. First pass perfusion images showed a subendocardial perfusion defect at the apex and thrombus lining the apex proven on long inversion time images. Late gadolinium enhancement (LGE) is seen in the apical endocardium and mid myocardium.
Learning Points from this Case:
Löeffler endocarditis (LE) is a rare type of restrictive cardiomyopathy characterized by abnormal eosinophilic infiltration with degranulation and endomyocardial fibrosis. It may be seen in any eosinophilic state including drug reactions (methysergide, ergotamine), parasitic infections, Hypereosinophilic Syndrome (HES), a myeloproliferative disorder marked by persistent peripheral eosinophilia (>1.5 × 109/L) and end-organ damage. In the initial stages of LE, eosinophilic infiltration and degranulation result in endo and myocardial damage/necrosis. This is the followed by a thrombotic phase and finally a fibrotic restrictive phase wherein there is scarring of the apical and mid LV endocardium, the inflow tracts, papillary muscles and chordae. Thrombus formation and embolic phenomena are common. Valvular regurgitation and pericardial effusions are common.
Differentials include apical hypertrophic cardiomyopathy, carcinoid heart disease, metastatic tumors and ventricular non-compaction. Diagnosis is often late once patients become symptomatic from underlying heart failure. Treatment of the underlying cause is the mainstay (e.g. chemotherapy), along with anticoagulation. Rarely, in advanced disease, surgical endocardial stripping can be considered. In our patient, the underlying disease state along with the classic CMR findings helped us establish and diagnosis and treat the underlying cause even though endomyocardial biopsy was not feasible.