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Concomitant presence of membranous obstruction of inferior vena cava and mitral stenosis.

I read with interest the case report presented in the paper ‘Association of mitral stenosis and membranous obstruction of the inferior vena cava’ by Wang and Tseng [1]. The concomitant presence of membranous obstruction of the inferior vena cava (MOVC) and mitral stenosis, though rare, has important clinical implications. Besides the two points the authors discussed, namely, the two being causally related and MOVC being ‘protective’ against pulmonary hypertension secondary to mitral stenosis, there is a third point of clinical importance that they failed to mention. Because balloon mitral valvulo-plasty has to be carried out percuta-neously via the femoral vein, the existence of MOVC poses a technical problem to the passage of the transseptal needle, especially in the complete form of MOVC. It was actually this unexpected combination in one of the patients which prompted my colleagues in Guangzhou Cardiovascular Institute, Canton, China, to originally consider MOVC a contraindication to percutaneous balloon mitral valvuloplasty [Chen, pers. commun]. With the use of an Inoue balloon catheter as a therapeutic tool for treatment of MOVC [2, 3], the combination of MOVC and mitral stenosis no longer poses a technically insurmountable problem. What was considered a contraindication in a patient with mitral stenosis to balloon mitral valvuloplasty now becomes an indication. References Wang TL, Tseng YZ: Association of mitral stenosis and membranous obstruction of the inferior vena cava. Cardiology 1994;85:365-367. Yang XL, Chen CR, Cheng TO: Nonoperative treatment of membranous obstruction of the inferior vena cava by percutaneous balloon transluminal angioplasty. Am Heart J 1992;124:405-412. Cheng TO, Yang X, Chen C: Membranous obstruction of the inferior vena cava treated by percutaneous balloon angioplasty. Circulation 1994;89:896-897.