Intracardiac masses: tumour or thrombus? Risk factors and non-invasive differentiation
K Badura, A Baszkowski, P Palka, M Jozwik, A Misiewicz, M Nadel, K Sliz, M Krejca, J DrozdzAbstract
Background
Primary heart tumours (PHT), despite being rare, present a diagnostic challenge due to their similarity to intracardiac thrombi. Misclassification delays proper, guideline-recommended therapy and is known to have a negative impact on patient mortality. Heart failure (HF) is a common comorbidity in both groups, further complicating the clinical picture.
Purpose
The aim of this study was to perform a comparative analysis of primary cardiac tumours and intracardiac thrombi, with emphasis on prevalence and impact of heart failure. Additionally, we sought to investigate potential prognostic markers.
Methods
This was a single-centre retrospective study which enrolled 185 adult patients with intracardiac masses between 2015 and 2025. We analysed demographic data, medical history, comorbidities, baseline symptoms and electrocardiogram, transthoracic, transoesophageal echocardiogram, laboratory test results and in-hospital interventions. Patients with suspicion of metastasis or with thrombus located on mechanical valves were excluded from this study.
Results
Of 185 patients included in the analysis, 82 were diagnosed with PHT whereas 103 with intracardiac thrombus. Patients with primary heart tumours had significantly lower N-terminal pro-B-type natriuretic peptide (NT-proBNP) on admission (median [interquartile range Q1-Q3 (IQR)]: 299.25 [130.1-1704] vs. 2644.5 [979.15-6074.5] pg/mL, p<0.001). Heart failure diagnosis was more likely present in thrombus group (odds ratio [OR] 3.48 [95% confidence interval (95% CI) 1.89-6.41], p<0.001) as well as previous myocardial infarction (MI) (OR 7.18 [95% CI 3.01-17.12], p<0.001) and atrial fibrillation (AF) (OR 2.73 [95% CI 1.39-5.35], p=0.003). Thrombi were more likely located within left ventricle (LV) (OR 11.37 [95% CI 4.77-27.07], p<0.001), whereas location within the left atrium (LA) (excluding the appendage) favours PHT diagnosis (OR 6.58 [95% CI 3.44-12.57], p<0.001). PHT were more likely pediculated (OR 14.3 95% CI 5.92-34.60], p<0.001) and larger (median diameter: 28 [IQR 18-45] vs. 19 [IQR 12-30] mm, p<0.001). Patients with PHT had significantly better LV and RV systolic function defined as LVEF (p<0.001) and TAPSE (p<0.001), whereas LAVI was notably lower (p=0.002). Patients with PHT had significantly better survival than patients diagnosed with intracardiac thrombi (Log-Rank p<0.001, median follow-up: 37 [IQR 6-77] months).
Conclusions
Patients with intracardiac thrombi present with higher prevalence of HF, prior MI and AF, alongside significantly higher levels of NT-proBNP on admission. Location of intracardiac masses could guide the diagnosis – thrombi are often located within the left ventricle, while primary cardiac tumours are mostly located in the LA, excluding the appendage. Multiple echocardiographic parameters such as LVEF, TAPSE, and LAVI are key diagnostic indicators. Moreover, patients with primary heart tumours had better survival compared to intracardiac thrombi.Figure 1For image description, please refer to the figure legend and surrounding text.Figure 2For image description, please refer to the figure legend and surrounding text.