SILENT GIANT LEFT ATRIUM

Abstract

TOPIC: Cardiovascular Disease TYPE: Global Case Reports INTRODUCTION: Enlarged LA is a common finding in severe mitral stenosis(MS) and severe mitral regurgitation(MR). It can enlarge to giant proportions. The unusual finding in a thirty-year-old woman presenting with only mild dyspnea despite a hugely dilated LA prompted us to report this case CASE PRESENTATION: A thirty-year-old woman presented to the outdoor clinic with the complaint of dyspnea on exertion NYHA class I. Aside from mild shortness of breath during the past year, she had been asymptomatic all her life. The admission electrocardiogram showed atrial flutter with the variable block while her chest roentgenogram showed marked cardiac enlargement. The right heart border showed a double contour of atrial shadow (Fig.2). An echocardiogram showed a giant left atrium measuring 14.4 X 16.7 cm that encroached on the other cardiac chambers (Fig.3). Thickened mitral valves along with doming and restricted motion of anterior and posterior mitral leaflets were diagnostic of rheumatic heart disease(RHD) It was surprising to find a relatively asymptomatic patient despite the marked distortion of cardiac anatomy. DISCUSSION: Giant LA occurs due to many reasons but most commonly its result from long-standing rheumatic mitral valve regurgitation or mixed mitral valve disease with predominant regurgitation. Two factors implicated in its development are increased LA pressure and weakening of the LA wall by Rheumatic Pancarditis. When mitral valve disease persists for long, it leads to LA enlargement as a compensatory mechanism to ease the markedly increased LA pressure which could lead to pulmonary Congestion due to backpressure hemodynamic and hence protect from the development of pulmonary hypertension. These compensatory mechanisms help patients survive asymptomatically for a long time. Giant LA can lead to various complications including thromboembolism, pulmonary edema, pulmonary hypertension and it can compress the esophagus and airway causing Dysphagia. CONCLUSIONS: Progressive LA enlargement might be undetected and well-tolerated for a long time, even when it reaches massive proportions. When the LA enlarges to a gigantic size, a chest x-ray is insufficient to delineate the cause of cardiomegaly and even can be misleading. An echocardiographic study is the most useful method for evaluating these patients. Our case was unusual because the giant LA distorted the cardiac structures. This led to striking cardiomegaly on the chest x-ray, and it confused interpreting the cause of the enlarged cardiac silhouette. The echocardiogram was very helpful in demonstrating the severe MS and the giant LA. There is a poor correlation between the size of the left atrium and the severity of the MS. REFERENCE #1: Kawazoe K, Beppu S, Takahara Y, Nakajima N, Tanaka K, Ichinashi K, Fujita T, Manabe H: Surgical treatment of giant left atrium combined with mitral valvular disease. Plication procedure for reduction of compression to the left ventricle, bronchus, and pulmonary parenchyma. J Thorac Cardiovasc Surg 1983, 85: 885-892. REFERENCE #2: Hurst W: Memories of patients with a giant left atrium. Circulation2001, 104: 2630-2631. 10.1161/hc4701.100775 REFERENCE #3: Plaschkes J, Broman JB, Mercin G, Milwidsky H: Giant left atrium in rheumatic heart disease: a report of18 cases treated by mitral valve replacement. Ann Surg 1971, 174: 194-201. 10.1097/00000658-197108000-00004 DISCLOSURES: No relevant relationships by Vikash Jaiswal, source=Web Response no disclosure submitted for Akshyaya Pradhan; No relevant relationships by Prachi Sharma, source=Web Response No relevant relationships by Shweta Vohra, source=Web Response