Confusion over thiazolidinedione-induced heart failure: need for a better definition of heart failure

Evaluation of: Erdmann E, Wilcox RG. Weighing up the cardiovascular benefits of thiazolidinedione therapy: the impact of increased risk of heart failure. Eur. Heart J. 29(1), 12-20 (2008). Thiazolidinediones (TZDs) reduce insulin resistance through the modulation of peroxisome proliferator-activated receptor (PPAR)-gamma activity and are, therefore, used for the treatment of individuals with Type 2 diabetes. TZDs have been blamed for inducing heart failure (HF) and are contraindicated in patients with impaired ventricular function. Whether precipitation of HF by TZDs is overestimated or not remains hotly debated in the scientific community. One message from the TZD-HF debacle is that current definitions of HF lack scientific rigour as they fail to assess cardiac organ function directly using a representative and reliable method. Once cardiologists reappraise and update the current definition of HF, appropriate steps can then be taken to answer the question of whether TZDs really induce true HF.