New Onset Cardiac Murmur and Exertional Dyspnea in an Apparently Healthy Child: A Rare Localization of Obstructive Myxoma in the Right Ventricle Outflow Tract without Pulmonary Embolization-A Case Report and Literature Review.

Myxomas are slowly growing benign neoplasms which are rare in children. Up to 80% can be located in the left atrium and generate symptoms such as embolism, cardiac failure, fever and weight loss. Rarely, myxomas can be detected in the right ventricle outflow tract, causing arrhythmias, pulmonary emboli and sudden death. We report the case of a 13-year-old healthy child brought to the Emergency Department (ED) of the Children's Hospital Bambino Gesù, Rome, for recent dyspnea, chest pain on exertion and new onset cardiac murmur. Patient underwent medical examination and echocardiogram with the finding of a rounded and lobulated voluminous mass in the right ventricle outflow tract (RVOT) which caused severe obstruction. The contrast computed tomography (CT) scan confirmed the presence of a heterogeneously enhancing soft-tissue mass occupying the RVOT with no evidence of pulmonary embolization. The mass was surgically excised, and the pathologic examination confirmed our suspicion of myxoma. Our experience suggests that myxoma can have mild clinical symptoms, the presentation may be non-specific, and diagnosis can be a challenge Careful examination and a diagnostic imaging workup, primarily with the transthoracic echocardiogram, are needful to make a rapid differential diagnosis and to better manage surgical treatment and follow-up.

Electroanatomic mapping-guided localization of alternative right ventricular septal pacing sites in children.

BACKGROUND: Alternative right ventricular (RV) sites (RVAPS) have been proposed to prevent or reduce RV pacing-induced left-ventricular (LV) dysfunction. Nonfluoroscopic 3D electroanatomic mapping systems (EAM) have been developed to guide cardiac catheter navigation and reduce fluoroscopy during electrophysiological procedures or pacemaker implantations. AIM: The aim of the study was to compare the results of EAM-guided permanent pacemaker implantation aiming at RVAPS with conventional fluoroscopic-guided implantation in RV apex (RVA) in children and adolescents. METHODS: A prospective, randomized analysis was performed on children/adolescents with complete atrioventricular block (CAVB) who underwent EAM-guided pacemaker and transvenous leads implantation into RVAPS (EAM-RVAPS) or conventional, fluoroscopic-guided implantation into RV apex (RVA). In EAM-RVAPS, a pacing map guided the implantation of ventricular leads in septal sites with narrower QRS. After implantation, LV contractility (ejection fraction [EF], Global Longitudinal Strain [GLS]) and synchrony were evaluated at 1-12 months. RESULTS: Twenty-one pediatric patients with CAVB, with (six patients) or without structural heart diseases, aged 4-16 (median 10.5) years, were divided in two groups: EAM-RVAPS (11 patients, four dual-chamber/DDD, seven single-chamber/VVIR pacemakers) and RVA (10 patients, one DDD/nine VVIR). The two groups did not show significant differences for preoperative parameters. EAM-RVAPS showed: preserved LVEF and synchrony (not significantly different than RVA), significantly lower GLS and radiation doses/exposures, in spite more complex procedures, significantly longer procedure times and narrower paced QRS than RVA. CONCLUSIONS: EAM-guided procedures have been useful to reduce radiation exposure and to localize RVAPS with narrower paced QRS and lower GLS than RVA.