Cardiac Rhabdomyomas Tuberous Sclerosis

Case with RV and RVOT predominantly involved

Case with LV and LVOT predominantly involved

Presentation by Laila Wazneh (NNP) and Nasir Mohammad (Neonatal Perinatal Medicine Fellow at McGill University) on Cardiac Rhabdomyoma

Pathological Example

More of fetal cardiac rhabdomyomas here.

Here, cardiac rhabdomyomas seen in the context of tuberous sclerosis. These are benign cardiac tumours often seen during fetal life. These tumours may cause LVOT obstruction. As such, when assessing these patients, one must pay particular attention to LVOT flow by colour flow and measure gradient. More on cardiac rhabdoymyomas by clicking here.

Case with RV and RVOT predominantly involved

Parasternal long axis view with a posterior sweep outlining that the RV cavity is filled with an echogenic mass.

View of the tricuspid valve in the PLAX outlining that there is a narrowing of the orifice, and filling of the RV cavity with an echogenic mass.

Parasternal short axis view, outlining that the rhabdomyoma involves the inter-ventricular septum, and the majority of the RV body, with some preservation of the RVOT area (which seems free of the presence of a mass, as well as some narrow opening at the level of the RV inflow.

Apical view outlining that there is a rhabdomyoma filling the RV cavity, as well as a smaller rhabdomyoma at the level of a papillary muscle of the mitral valve, with no obstruction of the LVOT

RV cavity filled with this irregular shapped cardiac mass, which is dense and uniform in echogenecity. The inflow portion of the LV is preserved, but there are thickening of the papillary muscles that outlines the involvement of rhabdomyomas at the level of the LV cavity as well. The rhabdomyoma extends to the RV inflow, with involvement of the tricuspid valve apparatus.

Subcostal views. The rhabdomyoma is filling the majority of the RV cavity. There is preservation of the LVOT and most of the LV cavity. The compliance of the RV may be altered in this context.

4 chamber view outlining that the mass is not vascular. It also outlines that there is blood flow entering via the narrow inflow area of the RV, by colour. The echogenic mass extends inside the right atrium. There is involvement of the interventricular septum. The LV inflow tract seems preserved, despite the presence of a smaller rhabdomyoma present in the LV cavity, abutting a papillary muscle of the mitral apparatus.

Sweep in the apical view outlining that the RVOT is relatively spared with opening and closure of the pulmonary valve.

Blood flow originates below the pulmonary valve and goes beyond the pulmonary valve via the colour Doppler evaluation. The PDA can be seen (red flow) shunting left to right.

Parasternal axis view with a sweep outlining the presence of this significant rhabdomyoma in the RV cavity.

Apical view showcasing the significant rhabdomyoma in the RV cavity.

Apical 2 chamber view of the LV: the LV cavity seems relatively spared and filling adequate.

LVOT is unobstructed. The mass abuts the interventricular septum.

RV focused apical view.

Subcostal views showcasing the short axis of the RV and the LV with RV rhabdomyoma (large) and a small LV rhabdomyoma. The last panel outlines the frame with the LV rhabdomyoma.

Blood flow filling the RV via the narrow inflow.

Inflow velocity of the RV

Blood flow via the RVOT (originates below the valve).

Left to right small ductus. Typically, PVR less than SVR and the ductus will shunt left to right in the post-natal setting. However, some infants may be ductal dependent for their pulmonary blood flow. Typically, infants that are significantly desaturated (because of the Right to Left inter-atrial shunt) are at risk of being ductal dependent. Those normally saturated are unlikely to be dependent on ductal contribution to pulmonary blood flow. However, these infants should be monitored until ductal closure to ensure there is no significant contribution of the ductus to the pulmonary circulation. Some may require PGE for ductal patency. More information in the powerpoint available below.