|No 16-05: The role of multimodal imaging in the diagnosis and management of a Cardiac Vascular Mass|
The role of multi-modal imaging in the diagnosis and management of a cardiac vascular malformation
G.K. Gnanappa, M. Krivanek, Phil A. Roberts, J. Ayer
Westmead Children's Hospital, Sydney, Australia
An asymptomatic 4-month-old male infant was referred for assessment of a heart murmur. An echocardiogram demonstrated a large (19x11 mm) mass arising from the basal inter-ventricular septum, encroaching on the right ventricular outflow tract (RVOT), producing mild RVOT obstruction (movie 1).
Movie 1: Echocardiogram - Subcostal long axis color Doppler view shows the mass arising from the basal interventricular septum and protruding into the RVOT with mild flow acceleration.
Movie 2: b-SSFP cine image of the RVOT in the sagittal plane shows that the mass arises from the basal interventricular septum and protrudes into the RVOT. The mass is iso-intense to the normal myocardium.
Fig. 1a Fig. 1b
Fig 1a: T1 TSE sequence shows the mass in the basal interventricular septum (arrow), iso-intense with normal myocardium.
Fig 1b: T2 STIR sequence shows the mass in the basal interventricular septum (arrow), hyper-intense compared with normal myocardium.
Fig. 1c: Delayed gadolinium enhancement image shows nulled normal myocardium whereas the mass shows intense enhancement resulting from the accumulation of gadolinium.
Movie 3: First pass contrast enhanced perfusion sequence in the short axis plane of the RV and LV shows earlier and brisk perfusion of the mass, suggestive of a highly vascular lesion. It also shows normal myocardial perfusion.
These features suggested a vascular lesion; an endomyocardial biopsy and coronary angiography were then performed, respectively to aid differentiation between benign and malignant vascular lesions and to better define the relationship to the LAD. Selective left coronary artery angiography demonstrated an instant blush, moderately dilated left coronary artery with unobstructed branches and perforating vessels to the mass (movie 4).
Movie 4: Coronary angiogram
The biopsy specimens revealed a large number of tortuous blood vessels of variable wall thickness intertwined within the myocardium. GLUT-1 Immunoperoxidase staining was negative (Figure 2 a, b).
Fig 2a: Multiple irregular vascular profiles within myocardium, some thin-walled with a dilated lumen, others thicker-walled with a narrow lumen. H+E stain. Original magnification x200.
Fig 2b: CD 31 immunostaining of the endothelium highlights the aberrant blood vessels. Original magnification x200.
A diagnosis of vascular malformation (either capillary, venous or combined) was made, as per the criteria of the International Society of the Study of Vascular Anomalies (1).
As the RVOT obstruction was mild and spontaneous involution or non-progression was possible, a conservative approach was followed. Due to the finding of GLUT-1 negative staining, beta blockers were also not trialed as they have proven benefit only in GLUT-1 positive infantile haemangioma (2). The patient has remained well at 3 years follow-up with no significant progression in the size of the mass or RVOT obstruction on echocardiogram.
1. ISSVA Classification of Vascular Anomalies ©2014 International Society for the Study of Vascular Anomalies. Available at "issva.org/classification”.
SCMR COTW Associate Editor: Sylvia Chen, MD