Can cardiovascular MRI be used to more definitively characterize cardiac masses initially identified using echocardiography?

Current status of diagnosis and treatment of primary benign cardiac tumors in children

Primary cardiac tumors in children are exceedingly rare overall, which benign account for most part. The onset of the disease is occult, while the clinical manifestations are non-specific-patients may be asymptomatic or show a range of obstructive, arrhythmic, embolic or systemic symptoms. The clinical presentations generally depend on the tumors’ size, localization, and pace of growth of the tumor. Moreover, the diagnosis needs comprehensive judgment based on imaging results and pathological examination. With advances in cardiac imagining and the introduction of cardiopulmonary support, the diagnosis and treatment of these rare tumors have improved the prognosis and outlook for benign tumors. To sum up the above, we sought to integrate articles from recent years for the latest comprehensive review of the clinical manifestations, imaging characteristics, clinic pathologic features and treatment of benign cardiac tumors in children to provide a broader idea for pediatricians to recognize and treat such diseases.

Multimodality Imaging of Benign Primary Cardiac Tumor

Primary cardiac tumors (PCTs) are rare, with benign PCTs being relatively common in approximately 75% of all PCTs. Benign PCTs are usually asymptomatic, and they are found incidentally by imaging. Even if patients present with symptoms, they are usually nonspecific. Before the application of imaging modalities to the heart, our understanding of these tumors is limited to case reports and autopsy studies. The advent and improvement of various imaging technologies have enabled the non-invasive evaluation of benign PCTs. Although echocardiography is the most commonly used imaging examination, it is not the best method to describe the histological characteristics of tumors. At present, cardiac magnetic resonance (CMR) and cardiac computed tomography (CCT) are often used to assess benign PCTs providing detailed information on anatomical and tissue features. In fact, each imaging modality has its own advantages and disadvantages, multimodality imaging uses two or more imaging types to provide valuable complementary information. With the widespread use of multimodality imaging, these techniques play an indispensable role in the management of patients with benign PCTs by providing useful diagnostic and prognostic information to guide treatment. This article reviews the multimodality imaging characterizations of common benign PCTs.

Cardiovascular Imaging in Cardio-Oncology: The Role of Echocardiography and Cardiac MRI in Modern Cardio-Oncology

Cardiovascular (CV) events are an increasingly common limitation of effective anticancer therapy. Over the last decade imaging has become essential to patients receiving contemporary cancer therapy. Herein we discuss the current state of CV imaging in cardio-oncology. We also provide a practical apparatus for the use of imaging in everyday cardiovascular care of oncology patients to improve outcomes for those at risk for cardiotoxicity, or with established cardiovascular disease. Finally, we consider future directions in the field given the wave of new anticancer therapies.

Diagnostic test accuracies of F-18 FDG PET for characterisation of cardiac masses compared to conventional imaging techniques: systematic review and meta-analysis

OBJECTIVE

The present systematic review and meta-analysis compared the diagnostic performance of F-18 fludeoxyglucose positron emission tomography (18F-FDG PET) and conventional imaging, including MRI, echocardiography, and CT, in characterising cardiac masses.

METHODS

A literature search of the PubMed, Cochrane, and EMBASE databases for studies comparing the diagnostic accuracies of 18F-FDG PET and conventional imaging in characterising cardiac masses, from inception of indexing to 31 July 2020, was performed. The Quality Assessment of Diagnostic Accuracy Studies-2 tool was used to assess study quality. Sensitivity and specificity across the studies were determined, positive and negative likelihood ratios (LR+ and LR-, respectively) were calculated, and summary receiver operating characteristic curves were constructed.

RESULTS

Of six included studies (n = 212 patients), 18F-FDG PET demonstrated a pooled sensitivity of 0.89 (95% confidence interval [CI] 0.81-0.94) and a pooled specificity of 0.89 (95% CI 0.80-0.94). LR syntheses yielded an overall LR+ of 7.9 (95% CI 4.3-14.6) and LR- of 0.12 (95% CI 0.07-0.22). The calculated pooled diagnostic odds ratio (DOR) was 64 (95% CI 23-181). For conventional imaging, the pooled sensitivity was 0.70 (95% CI 0.57-0.81) and the pooled specificity was 0.96 (95% CI 0.88-0.98). LR syntheses yielded an overall LR+ of 16.1 (95% CI 5.8-44.5) and LR- of 0.31 (95% CI 0.21-0.46). The evaluated pooled DOR was 52 (95% CI 17-155).

CONCLUSION

18F-FDG PET and conventional imaging demonstrated comparable diagnostic accuracies for the characterisation of cardiac masses. Further large multicentre studies are, however, required to corroborate the diagnostic performances of 18F-FDG PET and conventional imaging for the characterisation of cardiac masses.

ADVANCES IN KNOWLEDGE

No previous studies have comprehensively analysed the diagnostic performance of 18F-FDG PET/CT compared with conventional imaging techniques including echocardiography, CT, and MRI. According to the current study, 18F-FDG PET/CT yielded a pooled DOR of 64, whereas other conventional imaging techniques demonstrated a DOR of 52. As such, 18F-FDG PET/CT demonstrated sensitivity and specificity, with a high pooled DOR comparable with other conventional imaging modalities.

Differential and prognostic value of cardiovascular magnetic resonance derived scoring algorithm in cardiac tumors

OBJECTIVES

To establish a scoring algorithm based on cardiovascular magnetic resonance (CMR) parameters for differentiating between benign and malignant cardiac tumors and for predicting outcome.

METHODS

Patients referred for CMR for suspected cardiac tumors were prospectively enrolled. Tumors were categorized as benign or malignant based on pathology, imaging, and clinical information. The CMR protocol included cine, T1-weighted, T2-weighted, first-pass perfusion, and late gadolinium enhancement (LGE) sequences. Variables independently associated with malignancy in the multivariable logistic analysis were used to construct the scoring algorithm, and receiver operating characteristic analyses were used to assess the ability to discriminate malignant from benign tumors. The ability of the score to predict outcome (all-cause mortality) was also assessed by Kaplan-Meier survival analysis.

RESULTS

Among the 105 enrolled patients, 74 had benign and 31 had malignant tumors. In multivariable analysis, the independent predictors of malignant tumors were invasiveness (odds ratio, OR = 11.4, 2 points), irregular border (OR = 5.8, 1 point), and heterogenous LGE (OR 10.6, 2 points). The area under curves (AUC) of the scoring algorithm was 0.912 (cut-off score of 5) and showed significantly higher AUCs than individual variables (all P < 0.05) in differentiating benign and malignant tumors. After median follow-up of 18.2 months, mortality was significantly higher in patients with a score of 5 than in patients with score ≤ 4.

CONCLUSIONS

The scoring algorithm based on CMR-detected invasiveness, irregularity of border, and heterogenous LGE is an effective method for differentiating malignant from benign cardiac tumors and for predicting outcome.

Local myocardial stiffness variations identified by high frame rate shear wave echocardiography

BACKGROUND

Shear waves are generated by the closure of the heart valves. Significant differences in shear wave velocity have been found recently between normal myocardium and disease models of diffusely increased muscle stiffness. In this study we correlate in vivo myocardial shear wave imaging (SWI) with presence of scarred tissue, as model for local increase of stiffness. Stiffness variation is hypothesized to appear as velocity variation.

METHODS

Ten healthy volunteers (group 1), 10 hypertrophic cardiomyopathy (HCM) patients without any cardiac intervention (group 2), and 10 HCM patients with prior septal reduction therapy (group 3) underwent high frame rate tissue Doppler echocardiography. The SW in the interventricular septum after aortic valve closure was mapped along two M-mode lines, in the inner and outer layer.

RESULTS

We compared SWI to 3D echocardiography and strain imaging. In groups 1 and 2, no change in velocity was detected. In group 3, 8/10 patients showed a variation in SW velocity. All three patients having transmural scar showed a simultaneous velocity variation in both layers. Out of six patients with endocardial scar, five showed variations in the inner layer.

CONCLUSION

Local variations in stiffness, with myocardial remodeling post septal reduction therapy as model, can be detected by a local variation in the propagation velocity of naturally occurring shear waves.