Kidney function and the prognostic value of myocardial performance index

Area of Science:

• Cardiology
• Nephrology
• Medical Imaging

Background:

• Decreased glomerular filtration rate (GFR) is an independent risk factor for cardiovascular disease.
• The myocardial performance index (MPI), calculated from isovolumetric relaxation time (IVRT), isovolumetric contraction time (IVCT), and ejection time (ET), predicts cardiovascular events.
• Assessing cardiac risk in individuals with reduced estimated GFR (eGFR) is crucial.

Purpose of the Study:

• To investigate the prognostic capability of MPI in assessing cardiac risk within the general population.
• To determine if MPI's predictive value for cardiovascular events differs between individuals with normal and reduced eGFR.

Main Methods:

• A prospective cohort study involving 1915 subjects from the general population.
• MPI was measured using color tissue Doppler imaging (TDI) M-mode.
• Multivariable adjusted Cox regression models were used to compare prognostic capabilities based on eGFR thresholds (≥75 vs. <75 mL/min/1.73 m²).

Main Results:

• A significant interaction was found between eGFR and MPI's prognostic capability (p < 0.001).
• MPI remained an independent predictor of the composite endpoint (heart failure, myocardial infarction, or cardiovascular death) only in participants with eGFR < 75 mL/min/1.73 m² (HR 1.18; 95% CI 1.02-1.38).
• In subjects with eGFR ≥ 75 mL/min/1.73 m², MPI was not a significant independent predictor (HR 1.14; 95% CI 0.94-1.39).

Conclusions:

• The myocardial performance index (MPI) demonstrates significant prognostic value for cardiovascular events specifically in individuals with decreased eGFR (<75 mL/min/1.73 m²).
• MPI may serve as a valuable tool for identifying elevated cardiac risk in the general population with impaired kidney function.
• Further research could explore integrating MPI into risk stratification protocols for patients with chronic kidney disease.