Type and dimensions can predict ventricular arrhythmias and cardiac death in primary benign cardiac tumors in children.

ABSTRACT

Despite being extremely rare in children, primary benign cardiac tumors can cause malignant ventricular arrhythmias (VA) or even sudden cardiac death. To assess the predictors of cardiovascular death and malignant VAs, we designed a retrospective single-center study enrolling paediatric patients. We defined as primary outcome a composite of cardiovascular death, sustained VT, ventricular fibrillation and rapid, symptomatic non-sustained VT. Our secondary endpoint was to assess the prevalence of clinically significant arrhythmias in our population. METHODS AND RESULTS: We fitted a multivariate Cox regression model to assess the predictors of the primary outcome. Over a period of 38 years, a total of 97 children were enrolled in the study. Among them, there were 73 rhabdomyomas, 13 fibromas, 3 myxomas, 3 teratomas, 1 lipoma, 2 haemangiomas and 2 fibroelastomas. Over a median follow up of 10.53 years, 16 patients met the primary outcome. Kaplan Meier unadjusted survival estimates showed that tumor dimensions larger than 2.3 cm and diagnosis of fibroma predicted worse outcomes compared with smaller tumors or other histotypes, (log rank p < 0.0002 and < 0.0001 respectively). In multivariate Cox proportional hazards analysis, diagnosis of fibroma and tumor dimensions were independently associated to the primary endpoint (HR 5.06, 95 %CI (1.3-19); and 1.26 • (1.05-11), respectively). Clinically significant arrhythmias were reported in 24.5 % of the study population. CONCLUSIONS: Among paediatric primary cardiac tumors, type and dimensions may predict the hazard of malignant VAs and cardiac death.