Effects of exercise on cardiac structure and function in patients with type 2 diabetes: a narrative review of prospective imaging studies.

Around 30% of patients with type 2 diabetes(T2D) develop heart failure and this leads to poor prognosis. Treatment with exercise intervention can improve left cardiac function at rest in T2D, but its effects on subclinical HF markers, maximal cardiac function during exercise, and right cardiac function are unknown. This review aimed to synthesize the effects of exercise on cardiac structure and function in patients with T2D from prospective cardiac imaging trials. The secondary aim was to address the methodological shortcomings of previous studies and map future avenues. Our synthesis showed that exercise interventions can improve left ventricular structure and systolic and diastolic function at rest and during exercise, and right ventricular systolic function at rest in patients with T2D. Study shortcomings were inadequate reporting of randomization, concealment, between-group point estimates, intervention adherence, attendance and adverse events. Future studies should investigate sex- and phenotype-specific effects of exercise on the left and especially right heart during rest and peak exercise, determine the optimal exercise intensity, duration and volume for inducing cardiac changes, and determine if cardiac changes translate to a long-term prognosis.