Intermittent mitral regurgitation due to Beall valve dysfunction: analysis of 13 patients with atrial fibrillation

A unique hemodynamic event was noted in long-term survivors of mitral valve replacement with the Beall prosthesis. The event was a result of intermittent valve dysfunction and transvalvular mitral regurgitation (MR). At cycle lengths longer than 0.9 second that were preceded by shorter cycle lengths, 8 of 13 patients with Beall valve prostheses who had chronic atrial fibrillation (AF) intermittently had a marked unexpected decrease in peak left ventricular systolic pressure and a simultaneous increase in left atrial or pulmonary artery wedge "v" wave pressure. This event, which is a result of intermittent, severe MR, occurred more frequently at longer cycle lengths. In all 8 patients with the finding, severe valve disc wear was found at operation; however, 5 of these patients had only trace or 1+ MR on left ventricular angiography. In contrast, the event did not occur in 11 patients in chronic AF with organic MR or non-Beall valve MR, despite an appropriate number of sufficiently long cycles. The absence of the event in 5 Beall valve patients with significantly faster heart rates than in those with the event may in part be a result of its dependence on cycle length. This hemodynamic event, when present in a Beall valve recipient in AF, is an indication for valve replacement, even in the absence of angiographic evidence of severe MR.