Dialysis patients have significant morbidity and mortality associated with left ventricular hypertrophy and cardiac failure. Aldosterone may have an important role in the development of myocardial hypertrophy and remodeling. Animal studies have demonstrated beneficial effects of aldosterone antagonists on myocardial hypertrophy, and human studies have shown significant survival benefit in a non-dialysis population with congestive heart failure. This study evaluates the effect of spironolactone (an aldosterone receptor antagonist) on cardiac hypertrophy in the end-stage renal disease population.