Data from 64.862 patients within 12 years demonstrated 127 (0.195 %) intracardiac masses consisting of; 36 primary tumors (0.056 %), 33 (0.050 %) primary benign, 3 (0.004 %) primary malignant; 20 (0.030 %) secondary tumors; 3 (0.004 %) cysts and 68 (0.104 %) thrombi respectively (Table 1).
Primary benign cardiac tumors
Twenty six myxomas were identified (78.79 % of benign tumors; 20.47 % of cardiac masses 0.04 % of the study group), followed by 5 papillary fibroelastomas (15.15 % of benign tumors; 3.94 % of cardiac masses, 0.007 % of the study group), 1fibroma and 1 lipoma (3.03 % of benign tumors, 0.78 % of cardiac masses, 0.001 % of the study group for both), all confirmed with surgery and histology. Seventeen (65.38 %) myxomas were located in the left atrium (LA) (Fig. 1A-J), 7 (26.92 %) in the RA (Fig. 1K, L), 2 (7.69 %) with atypical localizations, one at the mitral anterior leaflet chorda, the other originating from the pulmonary valve, 19 (73.07 %) with pedicles originating from fossa ovalis, 6 (23.07 %) sessile masses from atrial walls (Figure 1).
Five fibroelastomas (11.54 % of benign tumors; 3.94 % of cardiac masses, 0.007 % of the study group) were identified incidentally. Three of them small, sessile, immobile masses, two located on the atrial side of the mitral anterior leaflet, one on the atrial side of the posterior leaflet. The other two fibroelastomas were small, mobile masses with short pedicles, one on the pulmonary valve and the other attached to the tricuspid anterior leaflet chorda (Fig. 1M-P).
One lipoma and one fibroma were also incidentally observed. Lipoma was located at the left ventricular (LV) posterior wall, originating from epicardium, it was the only benign cardiac tumor definitely diagnosed by CMR. Fibroma was located on the ventricular basis of posterior mitral leaflet with undetermined preliminary diagnosis (3.03 % of benign tumors, 0.79 % of cardiac masses, 0.001 % of the study group for both) (Supplementary Table 1, Figure 1).
Primary malignant cardiac tumors
Three primary malignant tumors of the heart were identified (0.004 % of the study group). One rhabdomyosarcoma (33.33 % of malignant tumors, 0.79 % of cardiac masses, 0.001% of the study group) and 2 angiosarcomas (66,67 % of malignant tumors, 1.574 % of cardiac masses, 0.003 % of the study group) (Supplementary Table 2, Figure 2). The rhabdomysarcoma was a poly-lobulated, mobile mass originating from the posterior wall of the LV myocardium, completely filling the LV cavity and prolapsing into the LV outflow tract towards the aortic lumen, also infiltrating the right ventricle (RV) (Fig. 2A-D), with desmin-positive histology (Fig. 2E, F). Both angiosarcomas were huge masses originating from right atrioventricular groove infiltrating RA wall and cavity and RV lateral wall and pericardium (Fig. 2G-I), confirmed by histology (Fig. 2J), accompanied by pericardial effusion.
Secondary malignant cardiac tumors
These patients were histologically proven primary noncardiac cancers referred for echocardiographic examination of cardiac functions before initiation of chemotheraphy while they were on follow up in other clinics. In most of the patients, echocardiographic examinations were suboptimal due to deteriorated general condition. Because of limited body motion and difficulty to achieve standard echocardiographic imaging planes, CMR and / or CT were predominantly used for diagnosis.
Cardiac metastases or invasions of cancers were detected in 20 patients (15.75 % of cardiac masses, 0.03 % of the study group), with male dominancy (55 %). One of the cases were published before 18. Malignancies with cardiac metastases consisted of lymphoma (n=6, 30 %), mainly B-cell lymphomas (n=5) (Fig. 3 A, B); lung cancer (n=5, 25 %) (Fig. 3, C); sarcomas of bone and soft tissue (n=3, 15 %); breast cancer (n=2, 10 %); renal cell carcinoma (n=1, 5 %) (Fig. 3, D); hepatocellular carcinoma (n=1, 5 %) (Fig. 3 E); stage IV thymoma (n=1, 5 %); papillary thyroid cancer (n=1, 5 %) (Fig 3, F). Secondary cardiac tumors were predominantly observed in the atria (n=12), majority in the RA (n=9). Surgery was performed for only 7 patients with large RA masses causing symptoms of obstruction, and histology proved invasions or metastases of the primary tumor to the atrium (Supplementary Table 3, Figure 3).
Intracardiac cysts were found in 3 patients (2.36 % of cardiac masses, 0.004 % of the study group), all were hydatid cysts. The localizations of the cysts were bi-ventricular apical region (Fig. 4A-C), interventricular septum (Fig. 4D-F), LV lateral wall (Fig. 4G, H), all were confirmed by CT and / or CMR, with positive indirect hemagglutination tests. All patients underwent surgery (Fig. 4, F), and histology proved the diagnosis (Fig. 4, I) (Supplementary Table 4, Figure 4). Two of three cases were published before 19, 20.
An intracardiac thrombus was identified in 68 patients (53.54 % of cardiac masses, 0.104 % of the study group). Thirty one patients (45.59 %) had underlying cardiac diseases, 37 patients (54.41 %) with non-cardiac disorders. Ischemic heart disease with low ejection fraction (EF %), with dilated left ventricle and prominent regional wall motion abnormalities (n=12, 38.71%, EF 20-40 %) was the first range of cardiac disease related intracardiac thrombi, followed by coexistence of hypertension and atrial fibrillation (n=8, 25.8 %), valvular heart disease (n=6, 19.35 %), and a few patients with hypertrophic obstructive cardiomyopathy, peri-myocarditis, biventricular non-compaction, ruptured sinus of Valsalva, generalized atherosclerosis (n=1, 3.22 % for each). The majority of intracardiac thrombi with non-cardiac disorders was associated with malignancies (n=17, 45.94 %) followed by autoimmune diseases (n=13, 35.13 %); chronic kidney disease (n=4, 10.81 %), deep venous thrombosis related with immobilization (n=2, 5.40 %), and hereditary spherocytosis (n=1, 2.70 %) (Figure 5, Supplementary Table 5).
The thrombi developed in patients with cardiac diseases were mainly located in the left heart chambers; those with systolic dysfunction in the LV (n=16), hypertension and valvular heart disease accompanied by atrial fibrillation in the LA (n=8). All of the patients received anticoagulant treatment, five patients were operated on.
Intracardiac thrombi of the patients associated with malignancies (n= 17) were predominantly located in the RA (n=11), RV was the secondary heart chamber (n=3). Malignancies accompanied by thrombi were; lung cancer (n=4) (Fig. 5 A,B), renal cell carcinoma (n=3) (Fig. 5C), lymphoma (n=3), and single cases of endometrial (Fig. 5D), esophageal (Fig. 5E,F), breast, ovarian (Fig. 5G,H), gastric cancers, leiomyosarcoma and chronic lymphocytic leukemia. All of the patients received anticoagulant treatment, only a patient with breast cancer with a very large thrombus in the RA was operated. The autoimmune diseases (n=13) predominantly consisted of Behçet’s disease (n=7) (Fig. 5I, J) followed by rheumatoid arthritis (n=2) (Fig. 5K), lupus erythematosus with antiphospholipid syndrome (n=2) (Fig. 5L), Takayasu arteritis (n=1) and Wegener granulomatosis (n=1). The most frequently involved cardiac chamber in autoimmune diseases was RA (n=9), and infrequently LA (n=2), LV (n=1) and ascending aorta (n=1). Wegener granulomatosis, which was published before 21 with a large thrombus in the left ventricle underwent surgery, and others received medical treatment. Four chronic kidney disease patients on hemodialysis had 2 RA (Fig. 5M-O), 1 LA and 1 RV large thrombi, three of whom were operated. Two patients with deep vein thrombosis, due to trauma and tibia fracture in one and diabetic foot ulcer in the other had RV thrombi followed by pulmonary embolism, were treated medically, details can be viewed from Supplementary Table 5.