Non-bacterial thrombotic endocarditis with atypical presentation as
overt congestive heart failure
Introduction. Non-Bacterial Thrombotic Endocarditis (NBTE) is a form of
endocarditis associated with malignancy or autoimmune disorders.
Diagnosis remains a challenge as patients are often asymptomatic up to
embolic events or, rarely, valve dysfunction. We report a case of NBTE
with uncommon clinical presentation and identified with multimodal
echocardiography. Case presentation. An 82-year-old man presented to our
outpatient clinic reporting dyspnea. Past medical history included
hypertension, diabetes, kidney disease, and unprovoked deep vein
thrombosis. On physical examination, he was apyretic, mildly hypotensive
and hypoxemic, had a systolic murmur and lower limbs edema.
Transthoracic echocardiography revealed severe mitral regurgitation due
to verrucous thickening of the free margin of both leaflets, increased
pulmonary pressure, and dilated inferior vena cava. Multiple blood
cultures were negative. Transesophageal echocardiography confirmed
“thrombotic” thickening of mitral leaflets. Nuclear investigations
were highly suggestive of multi-metastatic pulmonary cancer. We did not
further proceed in the diagnostic workup and prescribed palliative care.
Discussion. Lesions seen on echocardiography were suggestive of NBTE:
they involved both sides of mitral leaflets, close to the edges, had
irregular shape and echo-density, a broad base, and no independent
motion. Criteria for infective endocarditis were not met and the final
diagnosis was paraneoplastic NBTE due to underlying lung cancer. We
remark the lack of definitive recommendations about treatment of NBTE
and the only role of anticoagulation to prevent systemic embolism.
Conclusions. We report a case of NBTE presenting with atypical symptoms
and likely related to the prothrombotic state induced by underlying lung
cancer. Provided the unconclusive microbiological tests, multimodal
imaging played a crucial role for the final diagnosis.