Diagnostic performance of CMR and transthoracic echocardiography in clinical evaluation of cardiac masses with histopathological correlation

Background

Echocardiography is the preferred initial imaging method for assessment of cardiac masses. However, CMR, with its excellent tissue characterization and wide field of view, can provide unique information in the evaluation of cardiac masses. Our objective was to identify CMR and echocardiographic parameters that predict the presence of tumor or malignancy in biopsy proven cardiac masses and to assess the potential added value of CMR to echocardiography in the evaluation of cardiac masses.

Methods

We retrospectively identified 50 patients (50% male, mean age 46 ± 17 years) referred for CMR evaluation of cardiac mass who underwent biopsy or resection with histopathological diagnosis. Echocardiography was performed prior to CMR in 44/50 (88%) of the cases. Echocardiographic and CMR characteristics of the mass were evaluated for their predictive value in distinguishing tumor versus non-tumor and malignant versus non-malignant masses based on histopathology as the gold standard. Tumors were classified as any benign or malignant (primary or metastatic) neoplasm found in or around the heart while non-tumors were classified as any other mass (eg, thrombus) found in this area.Binary logistic regression and ROC curves were used to assess the diagnostic utility of these imaging characteristics alone and in combination for prediction of tumor or malignancy. Wilcoxon rank-sum test was used to compare the number of times a correct pathologic diagnosis was provided by each imaging study.

Results

The diagnostic performance of echocardiography and CMR parameters found to be significantly predictive of tumor and malignancy on pathology are depicted in the table. A diagnostic model incorporating the aforementioned parameters on echocardiography and CMR found no added value of CMR to echo in the diagnosis of malignant versus non-malignant masses (AUC=.928 vs AUC=.891, p=0.4405). In the 44 cases with both imaging studies, CMR provided significantly more correct pathologic diagnoses compared to echocardiography (77% vs 43%, p<0.0001).

Table 1 Diagnostic performance of significant echocardiography and CMR parameters for the detection of malignancy and tumor on pathology

Conclusions

Although no single or combination of CMR parameters demonstrated significantly improved performance for diagnosing tumor or malignancy over echocardiography, CMR can provide useful information on the underlying histopathologic diagnosis compared to echocardiography alone.

Funding

NYU School of Medicine