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Imaging Management

In an endemic area, clinical findings and plain film studies usually suffice for the diagnosis. Confirmation by echocardiography can be readily obtained. If open heart surgery is contemplated, angiography or MRI will probably provide further useful preoperative information. Three things must be remembered about endomyocardial fibrosis: it is a progressive disease, it may show a dominance of one side or the other (though it is seldom truly unilateral), and the patients seldom present until cardiac failure has commenced. The radiographic findings will therefore be very dependent on the stage at which the disease is seen. Routine radiography will be of great assistance in right-sided dominance, but echocardiography and angiocardiography are important, particularly in distinguishing left-sided EMF from rheumatic disease. As more experience is gained, MRI may replace angiography except in some preoperative patients.

Annular Subvalvular Aneurysms


Annular subvalvular left ventricular aneurysm. Submitral aneurysm. Aortic subvalvular aneurysm. Subaortic aneurysm. Unusual cardiac aneurysms.


Annular subvalvular aneurysms of the heart occur below the aortic or mitral valve. The cause is unknown (syphilis, rheumatic fever and coronary artery disease being excluded in this definition). The aneurysms may be single or multiple.

Geographic Distribution

This disorder is largely confined to those of African ancestry and occurs equally in both sexes at ages from 6 to 45 years. The aneurysms occur in patients in West, Central, and South Africa, Brazil, and the West Indies, with sporadic cases being seen in Europe and North America. These aneurysms are very rare in Caucasians.


There is a racial predilection, which strongly suggests a genetic rather than environmental cause, particularly because patients with aneurysms live in many geographic locations. Otherwise little is known. Some early cases were incorrectly attributed to tuberculosis, mycotic infections, syphilis, and trauma. (There is a rare, separate entity, tuberculous left ventricular aneurysms, with characteristic histology. ) There is probably a congenital weakness at the junction of the myocardium and the annulus. It is perhaps surprising that they have not been found in infants.


The aneurysm usually begins just below the annular fibrotic ring of the mitral valve, behind the posterior leaflet (submitral aneurysm)(Fig. 25.16). From there it can extend in several directions (Fig. 25.17), either into the left ventricular myocardium where, if large enough, it will cause a contour bulge, or it may dissect around the mitral ring, leading to mitral incompetence. Some aneurysms burrow in the myocardium towards the septum, while others form a loculus which can extend above the mitral valve into the left atrial cavity. Thus a complex three-dimensional aneurysm with several loculi and multiple ostia can develop by internal dissection. Most of the loculi have a smooth endocardial lining, but any may contain one or more thrombi which can obliterate part of the cavity (Fig. 25.18). A thrombus may calcify at the endocardial junction. If large enough the aneurysm may become adherent to the pericardium, but rupture of an aneurysm is extremely unusual. The largest reported aneurysm was submitral and extended below the diaphragm and beneath the rectus abdominis muscle! The only associated remote lesions are the result of emboli.

A less common form of aneurysm, but analogous, can have its ostium beneath the aortic ring and dissect around that annulus to cause aortic incompetence (aortic subvalvular aneurysm). The coronary vessels may be displaced, but their lumens are not compromised. The valve cusps are usually normal but may thicken.

Fig. 25.16. Posterior aspect of heart showing deroofed, thrombus-filled, idiopathic annular, subvalvular, ventricular aneurysm which communicated with the left ventricle at the mitral valve ring level. This patient was an adult black male who died of cerebral thromboembolism. (From Rose 1995).

Fig. 25.17. Schematic representation of the possible pathways of a left ventricular aneurysm dissection extending from a submitral ostium to burrow through the left ventricular myocardium (1), into the left atrium (2) and around the annulus to the septum (3). The superior loculus contains a laminated clot.



Fig. 25.18 A-D. Longitudinal sections of a heart with left ventricular aneurysm displaying its origin from the atrioventricular ring, with left ventricular myocardial extension and a loculus containing thrombus. (arrows).

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Copyright: Palmer and Reeder