The eyes are the window to the heart: one case of cardiac amyloidosis with eyelid swelling as the initial symptom

Cardiac amyloidoses (CA), a disease caused by the precipitation of amyloid in myocardial extracellular matrix, is difficult to diagnose due to lack of specificity of the clinical manifestations, and can be easily misdiagnosed. The patient was a 59-year-old man showed symptoms of double eyelid swelling and chest tightness without obvious causes. Electrocardiograph (ECG) for many times reveal low voltage in limb leads and poor progression of R waves in V1-V3. Furthermore, the levels of brain natriuretic peptide (BNP) and cardiac Troponin I (cTnI) are increased. The results of echocardiography suggested symmetric thickening of the left ventricle (IVS: 12mm, LVPW: 12mm), granular echoes in myocardium, left ventricular diastolic dysfunction (level III) (EF57%). Urine K light chain<0.1mg/l (0-7.1mg/L), urine λ light chain: 30.39mg/l increment (0-3.9 mg/L). The bone marrow results suggested no significant plasma cell dyscrasia. Since the gold standard for CA diagnosis is histopathological examination, skin and muscle biopsies of both eyelids were completely examined, hematoxylin and eosin (HE) and Congo red staining, suggesting positive result of Congo red staining. The results of polarized light examination suggested the presence of birefringence of apple green. Immunofixation electrophoresis was carried out for the serum, Bence-Jones protein electrophoresis was carried out for the urine sample, and results suggested M-proteinemia of LAM. The initial symptom of this case was manifested in the eyelid, after excluding orbital disease, coronary heart disease, lung disease and hypertrophic cardiomyopathy, the patient was diagnosed as cardiac amyloidosis through eyelid biopsy, fully demonstrating that “the eyes are the window to the heart”.