CST3 and systolic heart failure: This important issue was recently addressed by Moran and co-workers in another report from the Cardiovascular Health Study [36] In that study, cystatin C levels were linearly associated with the incidence of systolic heart failure, whereas only the highest concentrations of cystatin C were predictive of diastolic heart failure [36], suggesting that there may be somewhat different pathophysiological pathways leading to these two types of heart failure.