Since 1985, the
thiazolidinedione pioglitazone has been widely used as an
insulin sensitizer drug for
type 2 diabetes mellitus (T2DM). Although fluid retention was early recognized as a safety concern, data from clinical trials have not provided conclusive evidence for a benefit or a harm on cardiac function, leaving the question unanswered. We reviewed the available evidence encompassing both in vitro and in vivo studies in tissues, isolated organs, animals and humans, including the evidence generated by major clinical trials. Despite the increased risk of hospitalization for
heart failure due to fluid retention,
pioglitazone is consistently associated with reduced risk of
myocardial infarction and
ischemic stroke both in primary and
secondary prevention, without any proven direct harm on the myocardium. Moreover, it reduces
atherosclerosis progression, in-
stent restenosis after coronary
stent implantation, progression rate from persistent to permanent
atrial fibrillation, and reablation rate in diabetic patients with
paroxysmal atrial fibrillation after
catheter ablation. In fact, human and animal studies consistently report direct beneficial effects on cardiomyocytes electrophysiology, energetic metabolism,
ischemia-reperfusion injury, cardiac remodeling, neurohormonal activation, pulmonary circulation and biventricular systo-diastolic functions. The mechanisms involved may rely either on anti-remodeling properties (endothelium protective,
inflammation-modulating, anti-proliferative and anti-fibrotic properties) and/or on metabolic (adipose tissue metabolism, increased
HDL cholesterol) and neurohormonal (renin-angiotensin-aldosterone system, sympathetic nervous system, and
adiponectin) modulation of the cardiovascular system. With appropriate prescription and titration,
pioglitazone remains a useful tool in the arsenal of the clinical diabetologist.