A decline in renal function is associated with a reduction in myocardial mechano-energetic efficiency in individuals at high cardiometabolic risk.

Background: Heart failure and chronic kidney disease are closely interrelated conditions with rising global prevalence and incidence. Depressed myocardial mechano-energetic efficiency (MEE), reflecting the left ventricle's capacity to convert chemical energy from oxidative metabolism into mechanical work, is recognized as an early marker of systolic dysfunction. This cross-sectional study aimed to investigate the relationship between estimated glomerular filtration rate (eGFR) and myocardial MEE in individuals at high cardiometabolic risk.

Methods: Myocardial MEE per gram of left ventricular mass (MEEi) (mL/sec*g^-1) was assessed via echocardiography in 3,572 adults participating in the CATAnzaro MEtabolic RIsk factors study. Participants were stratified into four categories based on eGFR (G1-G4), in accordance with the Kidney Disease: Improving Global Outcomes classification.

Results: Individuals with mildly to severely reduced eGFR (G2, G3 and G4 categories) exhibited a significant reduction in myocardial MEEi compared to the G1 group. In multivariate linear regression analyses, declining eGFR remained significantly associated with reduced MEEi, even after adjusting for a broad range of cardiometabolic confounders, including age, sex, BMI, lipid profile, glucose tolerance status, hsCRP, HOMA-IR index, and the use of glucose-lowering, antihypertensive, and lipid-lowering medications.

Conclusions: Our findings demonstrate that a consistent reduction in renal function across eGFR categories is independently associated with reduced myocardial MEEi in individuals with high cardiometabolic risk suggesting that even a mild decline in nearly normal renal function may contribute to altered myocardial energetics.