Intermittent mitral regurgitation due to Beall valve dysfunction: analysis of 13 patients with atrial fibrillation.
Itzkoff JM, Curtiss EI, Reddy PS, Uretsky BF, Shaver JA. Intermittent mitral regurgitation due to Beall valve dysfunction: analysis of 13 patients with atrial fibrillation. Am J Cardiol. 1984 Apr 01; 53(8):1071-4.