Cardiac arrest in a patient with a mobile right atrial thrombus in transit and amyloidosis

Primary amyloidosis is a rare disorder in which insoluble fibersare deposited in tissue and organs, impairing their function.Cardiac involvement occurs in up to 50% of patients with primaryamyloidosis. We describe a case of a 75-year-old admitted to our departmentafter he had a sudden cardiac arrest due to massive bilateralthrombotic occlusion of the pulmonary arteries. The echocardiogramrevealed many atrial thrombi swirling inside the right atriumand protruding into the tricuspid valve partly occluding it.Severe concentric hypertrophy of the left ventricle was alsopresent with a preserved ejection fraction. The right ventriclewas dilated, hypertrophic and ipokinetic with a severe tricuspidalinsufficiency that permitted estimation of a severe pulmonaryhypertension. All these characteristics were highly suggestivefor an infiltrative form of hypertrophic cardiomyopathy. Thefinal diagnosis was amyloidosis.