Diabetic cardiomyopathy (DbCM) is a condition characterized by diastolic dysfunction and metabolic disturbances in the heart of individuals with diabetes, more prevalent than previously recognized. It is defined as ventricular dysfunction in the absence of coronary artery disease or hypertension. Key mechanisms involve disruptions in cardiac substrate metabolism, including fatty acid oxidation, glucose metabolism, and amino acid/ketone metabolism. These disruptions lead to mitochondrial dysfunction, oxidative stress, and impaired energy production, contributing to diastolic dysfunction and cardiac fibrosis. DbCM shares features with heart failure with preserved ejection fraction (HFpEF), which is more common in diabetes. Understanding these metabolic changes is crucial for developing targeted therapies. DbCM is associated with increased myocardial fatty acid uptake, mitochondrial dysfunction, and impaired glucose metabolism. These metabolic disturbances are regulated by factors such as PPARα, which increases fatty acid oxidation and decreases glucose oxidation. Additionally, metabolic intermediates like acetyl CoA and lactate influence cellular processes through epigenetic modifications and post-translational modifications, affecting gene expression and protein function. Pharmacological approaches targeting these metabolic pathways, such as inhibiting fatty acid oxidation with trimetazidine or enhancing glucose oxidation with dichloroacetate, have shown promise in preclinical studies. Similarly, targeting amino acid and ketone metabolism with SGLT2 inhibitors and GLP-1 agonists has shown benefits in improving cardiac function in diabetic models. Despite these advances, the exact mechanisms linking metabolic disturbances to cardiac dysfunction remain unclear. DbCM is often undiagnosed in prediabetic or early-stage T2D patients, highlighting the need for improved diagnostic tools. Future research should focus on understanding the relationship between DbCM and HFpEF, as well as developing targeted therapies that address the underlying metabolic dysregulation. The proposed new definition of DbCM emphasizes diastolic dysfunction in the presence of altered myocardial metabolism without other known causes of cardiomyopathy or hypertension. This redefinition aims to better classify and treat DbCM, improving outcomes for individuals with diabetes.Diabetic cardiomyopathy (DbCM) is a condition characterized by diastolic dysfunction and metabolic disturbances in the heart of individuals with diabetes, more prevalent than previously recognized. It is defined as ventricular dysfunction in the absence of coronary artery disease or hypertension. Key mechanisms involve disruptions in cardiac substrate metabolism, including fatty acid oxidation, glucose metabolism, and amino acid/ketone metabolism. These disruptions lead to mitochondrial dysfunction, oxidative stress, and impaired energy production, contributing to diastolic dysfunction and cardiac fibrosis. DbCM shares features with heart failure with preserved ejection fraction (HFpEF), which is more common in diabetes. Understanding these metabolic changes is crucial for developing targeted therapies. DbCM is associated with increased myocardial fatty acid uptake, mitochondrial dysfunction, and impaired glucose metabolism. These metabolic disturbances are regulated by factors such as PPARα, which increases fatty acid oxidation and decreases glucose oxidation. Additionally, metabolic intermediates like acetyl CoA and lactate influence cellular processes through epigenetic modifications and post-translational modifications, affecting gene expression and protein function. Pharmacological approaches targeting these metabolic pathways, such as inhibiting fatty acid oxidation with trimetazidine or enhancing glucose oxidation with dichloroacetate, have shown promise in preclinical studies. Similarly, targeting amino acid and ketone metabolism with SGLT2 inhibitors and GLP-1 agonists has shown benefits in improving cardiac function in diabetic models. Despite these advances, the exact mechanisms linking metabolic disturbances to cardiac dysfunction remain unclear. DbCM is often undiagnosed in prediabetic or early-stage T2D patients, highlighting the need for improved diagnostic tools. Future research should focus on understanding the relationship between DbCM and HFpEF, as well as developing targeted therapies that address the underlying metabolic dysregulation. The proposed new definition of DbCM emphasizes diastolic dysfunction in the presence of altered myocardial metabolism without other known causes of cardiomyopathy or hypertension. This redefinition aims to better classify and treat DbCM, improving outcomes for individuals with diabetes.