We analyzed QRS interval for 6 months or more in 82 patients with dilated cardiomyopathy. At 1 year, the incidence of cardiac death/need for heart transplantation was higher among patients with QRS-interval widening of 0.5 msec/month or greater (p = 0.002). At multivariate analysis, QRS widening independently and unfavorably predicted cardiac death/need for heart transplantation (p = 0.029). Randomized prospective studies are necessary to confirm the prognostic value of accelerated QRS widening in patients with dilated cardiomyopathy and to investigate its significance in selecting candidates for electrical resynchronization and heart transplantation.