Clinical determinants and prognostic significance of the electrocardiographic strain pattern in chronic kidney disease patients

Abstract

The electrocardiographic (ECG) strain pattern (Strain) is a marker of left ventricular hypertrophy (LVH) severity that provides additional prognostic information beyond echocardiography (ECHO) in the community level. We sought to evaluate its clinical determinants and prognostic usefulness in chronic kidney disease (CKD) patients. We evaluated 284 non-dialysis-dependent patients with CKD stages 3 to 5 (mean age, 61 years [interquartile range, 53–67 years]; 62% men). Patients were followed for 23 months (range, 13–32 months) for cardiovascular (CV) events and/or death. Strain patients (n = 37; 13%) were using more antihypertensive drugs, had higher prevalence of peripheral vascular disease and smoking, and higher levels of C-reactive protein, cardiac troponin, and brain natriuretic peptide (BNP). The independent predictors of Strain were: left ventricular mass index (LVMI), BNP, and smoking. During follow-up, there were 44 cardiovascular events (fatal and non-fatal) and 22 non-CV deaths; and Strain was associated with a worse prognosis independently of LVMI. Adding Strain to a prognostic model of LVMI improved in 15% the risk discrimination for the composite endpoint and in 12% for the CV events. Strain associates with CV risk factors and adds prognostic information over and above that of ECHO-assessed LVMI. Its routine screening may allow early identification of high risk CKD patients.