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cardiac calcified amorphous tumors ( cats ) are extremely rare cardiac masses which can arise in all four cardiac chambers.1)2 ) while several causes of cardiac cats have been suggested , the true etiology is not still clear .
cardiac cats are usually benign , but sometimes cause diverse symptoms due to obstruction or embolization.1)3 ) we recently encountered a patient with a cardiac cat causing multiple , calcific , pulmonary emboli and right - sided heart failure . a cardiac cat has not been reported previously in korea .
a 33-year - old man sought evaluation in our outpatient clinic for progressive pretibial pitting edema and shortness of breath on exertion . there was no personal or family history of thromboembolic , hematologic , inflammatory , or malignant diseases .
the physical examination revealed mild icteric sclera , a palpable liver , a distended abdomen , and jugular vein distention .
a chest x - ray showed a dense calcification within the cardiac silhouette from the left lateral view .
an electrocardiogram revealed incomplete right bundle branch block , right atrial enlargement , and right ventricular hypertrophy .
echocardiography demonstrated a diffuse calcified mass affecting the tricuspid chordal apparatus and the free wall of the right ventricle ( rv ) , resulting in severe tricuspid regurgitation and markedly increased rv systolic pressure ( 70 mmhg ) ( fig .
1 ) . on laboratory analysis , the serum parathyroid hormone of 50.07 pg / ml ( normal , 15 - 65 pg / ml ) , calcium of 8.1 mg / dl ( normal , 8.0 - 10.5 mg / dl ) , creatinine of 1.0 mg / dl ( normal , 0.5 - 1.4 mg / dl ) , and glucose of 100 mg / dl ( normal , 70 - 110 mg / dl ) levels were within normal limits .
a chest computed tomography ( ct ) showed multiple pulmonary thromboemboli , possibly calcific , which were noted on non - contrast ct imaging ( fig .
2 ) . fluoroscopic imaging showed an irregular - shaped calcified mass in the rv which changed in shape and size during the cardiac cycle ( fig .
3 ) . cardiac magnetic resonance imaging ( mri ) demonstrated a tubular calcified mass , which was separated from the right ventricular myocardium , extending from just below the tricuspid valve annulus to the right ventricular outflow tract , suggesting a cat or calcific fibroma ( fig .
an endomyocardial biopsy was not performed due to the risk of right ventricular rupture or prolapse .
heart - lung transplantation was deferred until the pulmonary arterial pressure improved and empirical anticoagulation was administered .
a cardiac cat was first reported in 1997.4 ) cardiac cats can arise in all four chambers of the heart,1)2 ) although the proportion in each chamber is not known .
although mural thrombi,4)5 ) chest trauma,1 ) and increased parathyroid hormone and calcium phosphate product levels in hemodialysis patients6 ) have been described as the causes for cardiac cats , the pathogenesis of these lesions is still unknown . in the present case
histologically , a cardiac cat is characterized by nodular calcium deposits over a matrix of fibrin and/or amorphous fibrin - like material , hyalinization , inflammatory cells , and degenerated hematologic elements.7 ) clinical tests usually show cardiac cats to be benign , although they may cause obstruction or embolism,4 ) and cases can evolve fatally.5 ) an endomyocardial biopsy was not performed because of the risk of right ventricular rupture and further calcific embolization.8 ) surgical removal of the tumor may be indicated if embolism has occurred or seems likely .
complete surgical resection should be pursued if possible , considering its recurrence.5 ) heart transplantation may be considered if not possible .
we chose heart - lung transplantation in the present patient who had multiple calcified emboli and severe right ventricular dysfunction . during the differential diagnosis , cardiac neoplasias , especially myxomas and fibromas ,
are considerations , particularly if they are calcified , as are conditions involving infection or thrombosis.9 ) due to the lack of histology , calcified atrial myxoma , calcified thrombi or other cardiac neoplasms should be also considered as a differential diagnosis of calcific mass of rv .
echocardiography , and ct and mri provide important information on the size and shape , attachment site , and pattern of movement of the calcified tumor .
myxomas usually have a short , broad - based attachment and are pedunculated , although calcification may develop in approximately 10% of myxomas .
ct scans can detect intracardiac masses and define the extracardiac extension.10 ) ct scans can also detect even minute amounts of calcium , which facilitated detection of the calcific pulmonary embolism in the present case .
we recommend utilizing a multimodality imaging approach to accurately characterize intracardiac masses and their complications .
cardiac calcified amorphous tumors ( cats ) can arise in all four chambers of the heart . 
 cardiac cats can cause diverse symptoms according to their locations , and mass or embolic effects . 
 pulmonary emboli arising from cardiac cats have been reported , but the true incidence is unknown due to their rarity . herein we report a rare case with diffuse cats in the right ventricle which caused a calcific pulmonary embolism and right - sided heart failure . 
 echocardiography , chest non - contrast computed tomography , and cardiac magnetic resonance imaging helped us diagnose the cats . 
 we recommend the usefulness of a multimodality imaging approach to characterize intracardiac masses and their complications accurately .