Myocardial Work and Cardiovascular Events in Patients With Chronic Kidney Disease

BACKGROUND: Patients with chronic kidney disease (CKD) are at increased risk of cardiovascular (CV) events. Myocardial work indices represent novel echocardiographic measures that may reveal subtle but important abnormalities of left ventricular (LV) function.

METHODS: Patients with CKD were included prospectively and underwent echocardiography, including pressure-strain loop analyses to acquire myocardial work indices. These included the global work index (GWI), constructive work (GCW), wasted work (GWW), and work efficiency (GWE). Their association to major adverse cardiovascular events (MACE) - defined as heart failure (HF) and ischemic heart disease - were investigated by Cox regression. Competing risk regression was performed to account for all-cause death as a competing event.

RESULTS: We included 697 patients with CKD (mean age: 57 years, 60% men, median estimated glomerular filtration rate of 43 mL/min/1.73 m2), of whom 42 (6%) experienced MACE during a median follow-up of 3.9 (IQR: 3.4-4.5) years. In univariable analyses, all myocardial work indices were significantly associated with MACE. After multivariable adjustments, only GCW, GWW, and GWE remained significantly associated with MACE (GCW: HR 1.08 (1.00-1.17), per 100 mmHg% decrease; GWW: HR 1.05 (1.01-1.08), per 10 mmHg% increase; GWE: 1.15 (1.08-1.22), per 1% decrease), but only GWW and GWE were associated with MACE in multivariable competing risk regression. Notably, myocardial work indices were only associated with HF and not ischemic heart disease.

CONCLUSION: In patients with non-dialysis dependent CKD, wasted work and work efficiency were independently associated with MACE. These findings were driven by their association with HF.