Clinical Features of Cardiac Calcified Amorphous Tumor: A Narrative Review

A cardiac calcified amorphous tumor (CAT) is a non-neoplastic cardiac mass composed of calcified nodules surrounded by amorphous fibrous tissue in a context of degeneration and chronic inflammation. Although CAT cases are increasingly reported, its clinical manifestation remains unclear. We aimed to conduct a narrative review of CAT and identify its clinical characteristics. We conducted a comprehensive literature search using PubMed, with the keyword "Cardiac Calcified Amorphous Tumor" to identify relevant articles. A total of 113 articles published between 1997 and 2022 were retrieved. The clinical features allowing for assess patient background, differences with and without end-stage renal disease (ESRD), symptom-related factors, risk factors for embolism caused by CAT, and features of CAT, such as shape, location, mobility, pathology, and treatment, were statistically analyzed in 106 criteria-matched cases. The mean patient age was 60.2 ± 18.6 years, with 45 men and 61 women. Of the data collected from 21 countries, 52 patients were from Japan. Mobile CAT was more common in the chronic renal failure group. Linear, club-shaped, and spindle-shaped CAT tended to be mobile and more common in the ESRD group as well as located in the mitral valve region. The shape, mobility, location, and underlying mechanism of CAT depended on the presence or absence of ESRD. The risk of embolism was considered high because mobile CAT was more common in the ESRD group, and CAT originated in the mitral valve region. Hence, early diagnosis based on periodic examination in patients with ESRD and aggressive surgical treatment are necessary.