Changing conduction abnormalities in a dialysis patient with fever.

A patient on hemodialysis with severe aortic valve disease and presumed arteriovenous fistula infection was found to have new-onset atrial fibrillation and alternating left and right bundle branch block patterns on serial electrocardiograms. These findings prompted transesophageal echocardiography, which revealed a large abscess involving the intervalvular fibrosa and the posterior cusp of the bicuspid aortic valve. Hence, basic bedside diagnostic skills remain important in the era of sophisticated imaging techniques and laboratory analyses.