Diagnostic agreement between echocardiography and second-level imaging techniques in patients with cardiac masses

Abstract

Abstract Background Cardiac masses (CMs) are a diagnostic dilemma in clinical practice and require multimodality imaging to assess malignancy, which is essential to guide the proper treatment. Aim To define diagnostic accuracy and agreement between echocardiographic features and second-level imaging techniques (cardiac computed tomography – CCT or cardiac magnetic resonance – CMR) in patients with CMs. Methods All consecutive patients with histologically confirmed cardiac masses from January 2004 to December 2020, undergoing CCT and/or CMR after echocardiographic assessment were enrolled. Six echocardiographic variables, namely infiltration, polylobate mass, moderate-severe pericardial effusion, inhomogeneity, sessile and non-left localization, were used to predict malignancy. Patients with more than 3 of these features were considered at higher risk of malignancy. For the patients before 2017, the choice of which second-level imaging to perform was up to the clinical cardiologist. Since 2017, the has been the result of a multidisciplinary discussion by the Heart Team. A definitive diagnosis was achieved by histological examination or, in the case of cardiac thrombi, with radiological evidence of thrombus resolution after an appropriate anticoagulant treatment. The echo-vs-CCT agreement and echo-vs-CMR agreement were evaluated. Accuracy indicators (sensitivity, specificity, PPV, NPV, Cohen’s Kappa coefficient) were calculated by standard formulas. Results Out of 249 patients with histologically confirmed CM, 138 underwent a CCT and 112 a CMR, after the standard echocardiographic assessment. A complete agreement between the echocardiographic assignment (using the cut-off of 3 parameters as a marker for malignancy) and CCT was reached in 104 out of 138 cases (75.4%), ranging from 85.1 to 70.3% for benign and malignant cardiac masses, respectively. On the other side, the agreement between the echocardiographic assignment and CMR report was in 93 out of 112 cases (83%), ranging from 88.7 to 82% for benign and malignant cardiac masses. The agreement between these imaging techniques expressed as Cohen’s κ was higher for echocardiography versus CMR (k=0.73), compared to echocardiography versus CCT (k=0.61). These results were also confirmed by the higher diagnostic accuracy of echocardiography versus CMR compared to echocardiography versus CCT (87% vs 80%), with best values of sensitivity, and specificity, denoting good reliability between the first 2 techniques. Conclusions A multimodal imaging approach is mandatory in the diagnostic work-up of CMs. The CMR, after a standard echocardiographic assessment, turned out to be the most accurate second-level investigation to discriminate between benign and malignant masses. However, when CMR is not available or the patient has a contraindication, the CCT could still be reliable.