Pattern and Prognostic Implications of Cardiac Metastases Among Patients With Advanced Systemic Cancer Assessed With Cardiac Magnetic Resonance Imaging

Background: Cardiac magnetic resonance (CMR) imaging is well validated for tissue characterization of cardiac masses but has not been applied to study pattern and prognostic implications of cardiac metastases (CMETs) among patients with systemic cancer. Methods and Results: The population consisted of 60 patients with stage IV cancer (32 patients with CMETs, 28 diagnosis-matched controls) undergoing CMR. CMET was defined as a discrete mass with vascular tissue properties on delayed enhancement CMR. CMET-positive patients and controls had similar clinical characteristics, cardiac geometry, and function (P=NS). Leading cancer types associated with CMET were sarcoma, melanoma, and gastrointestinal. Patients with CMETs had similar distribution of extracardiac metastatic disease compared with controls (organs involved: 3.4±2.0 versus 2.7±1.9, P=0.17). In 94% of patients with CMETs, there were metastases involving ≥1 extracardiac organ (66% lung involvement). CMET location varied (right ventricle 44%, right atrium 19%, left ventricle 28%, left atrium 9%, pericardial 25%); 22% of cases had multichamber involvement. Right-sided chamber involvement was common in hematologic/lymphatic spread (67%); pericardial involvement was common with direct spread (64%). Regarding tissue properties on delayed enhancement CMR, CMETs commonly (59%) demonstrated heterogeneous enhancement (41% diffuse enhancement). Heterogeneous lesions were larger and had increased border irregularity (P<0.05). Survival 6 months post-CMR was numerically lower among patients with CMETs (56% [95% CI 39-74%]) versus stage IV cancer-matched controls (68% [95% CI 50-86%]), although differences between groups were nonsignificant (P=0.42). Conclusions: CMETs vary regarding etiology, location, and tissue properties on CMR, highlighting need for comprehensive surveillance of cardiac involvement regardless of cancer origin. Prognosis remains poor with for patients with CMETs, albeit similar to that for stage IV cancer controls matched for cancer etiology.