Primary amyloidosis is a rare disease, cardiac involvement occurs in up to 40% of patients. Diffuse amyloid deposits cause an impairment of myocardial systolic and diastolic function. In this paper we are presenting a case of a 54-year-old woman. The woman was admitted because of progressive fatigue, dyspnoea, chest pain, later she experienced hypotension, dyspepsia, and enterorrhagia. ECG showed decrease in QRS amplitude. We have found an echocardiographic evidence of wall hypertrophy. Right cardiac catheterization showed a restrictive situation. Immunobinding of serum and urine revealed monoclonal kappa light chains. The diagnosis was determined by rectal biopsy. Unfortunately, amyloid deposits caused progressive heart failure, hemorrhage, and death just before the diagnosis of primary amyloidosis could be determined on the basis of results of the immunofixations of serum and urine proteins (detection of the monoclonal light chains kappa) and from biopsy specimens taken from rectum (amyloid deposits).