Submitral aneurysm of varied aetiologies: a case series

Abstract

Background Submitral aneurysm is a rare disease initially described in the African population. It is usually considered congenital in origin, due to a defect in the posterior portion of the mitral annulus. However, it can be seen in other diseases like ischaemic heart disease, rheumatic heart disease, infective endocarditis, tuberculosis, and syphilis. Case presentation Case 1 was a 29-year-old female, hypertensive undergoing maintenance haemodialysis for chronic kidney disease and on anti-tubercular therapy. She was found to have a large submitral aneurysm with severe mitral regurgitation, moderate left ventricular dysfunction, and pericardial effusion on echocardiogram. Case 2 was a 58-year-old gentleman presented with inferior wall ST-elevation myocardial infarction and was thrombolyzed with streptokinase for the same. Echocardiogram done 6 months later for evaluation of dyspnoea showed a large inferobasal aneurysm. Case 3 was a 56-year-old hypertensive presented with dyspnoea on exertion and echocardiogram showed a large posterolateral region with transmural late gadolinium enhancement. Case 4 was a 13-year-old boy presented with fever and cerebrovascular accident. Echocardiogram revealed vegetation in the mitral valve and a small submitral aneurysm with vegetation inside it. Discussion Submitral aneurysm is usually considered congenital in origin. However, it can be due to ischaemic heart disease, rheumatic heart disease, Takayasu arteritis, and tuberculosis. Top dimensional echocardiogram is the investigation of choice. Cardiac magentic resonance imaging helps in identifying the underlying aetiology and delineating the surrounding structures.

Outcome of submitral aneurysm

“…However, histopathological evidence of direct invasion of myocardium by tubercular bacteria was not present in these patients, tuberculosis was suspected to be the cause of submitral aneurysm. Ischemic heart disease has been previously also been described as an etiology of the submitral aneurysm 4 . Three patients in our study had a submitral aneurysm after a documented episode of ACS.…”

“…Ischemic heart disease has been previously also been described as an etiology of the submitral aneurysm. 4 Three patients in our study had a submitral aneurysm after a documented episode of ACS.…”

“…Submitral left ventricular aneurysms are rare aneurysmal dilatations perceived presently to be developmental in origin 1 . Although a genetic link has been suspected because of racial predilection, it is now being frequently reported in regions other than the African continent including Brazil and India 2–4 . Although the initial cases reported a noninfectious and nontraumatic origin of the condition and pointed toward a congenital cause, recent reports have shown its etiology to be varied including ischemic heart disease, infective endocarditis, rheumatic heart disease, tuberculosis, trauma, and Takayasu arteritis, suggesting the role of inflammation and infection in the pathogenesis of this disease 5,6 .…”

Submitral aneurysm: Exploring a rare pathology

“…4 In contrast to posterior left ventricular aneurysms, which often occur due to ischemic etiology, SMAs are believed to be largely congenital in nature. 1,[4][5][6][7] The pathology likely stems from a weakening of the fibrous tissue of the posterior mitral annulus, which creates an outpouching between the annulus and the left ventricular endocardium that restricts the posterior mitral leaflet. 6 Nayak et al suggest the presence of a submitral curtain, a fibrous separation between the fibrous annulus and the left ventricular musculature, further predisposes patients to developing SMA.…”

“…6,10,11 While transmural infarction typically causes apical aneurysm, ischemia-induced SMAs have been documented in prior literature and in three patients in the authors' series. 1,7 Infectious agents such as human immunodeficiency virus (HIV) and tuberculosis have also been proposed as etiologies of SMA, as inflammation is suspected to contribute to the pathogenesis and may exacerbate the congenital pathology of SMA. However, it is still uncertain whether these infectious etiologies are causative or a coincidental reflection of the diseases endemic to the demographic in which SMA is typically found.…”