Exercise E/e' Is a Determinant of Exercise Capacity and Adverse Cardiovascular Outcomes in Chronic Kidney Disease

OBJECTIVES This study sought to assess the relationship between E/e' and exercise capacity in patients with chronic kidney disease (CKD) and evaluate its prognostic role. BACKGROUND Patients with CKD have diastolic dysfunction, reduced physical fitness, and elevated risk of cardiovascular disease. METHODS Patients with stage 3 and 4 CKD without previous cardiac disease underwent resting and exercise stress echocardiograms with assessment of exercise E/e'. Patients were compared to age-, sex-, and risk factor-matched control individuals and were followed annually for 5 years for cardiovascular death and major adverse cardiovascular event(s) (MACE). Exercise capacity was assessed as metabolic equivalents (METs), with reduced exercise capacity defined as METs of <= 7. Raised exercise E/e' was defined as >13. RESULTS A total of 156 patients with CKD (age 62.8 +/- 10.6 years; male: 62%) were compared to 156 matched control individuals. Patients with CKD were more likely to be anemic (p < 0.01) and had increased left ventricular mass (p < 0.01), larger left atrial volumes (p < 0.01), and higher resting (p < 0.01) and exercise E/e' (p < 0.01). Patients with CKD achieved lower exercise METs (p < 0.01), and more patients with CKD had METs of <= 7 (p < 0.01). Receiver-operating characteristic curves showed exercise E/e' (area under the curve [AUC]: 0.89; 95% CI: 0.84 to 0.95; p < 0.01) as the strongest predictor of reduced exercise capacity in patients with CKD. Over a follow-up period of 41.4 months, a raised exercise E/e' of >13 was an independent predictor of cardiovascular death and MACE on unadjusted and adjusted hazard models. CONCLUSION E/e' is a strong predictor of exercise capacity and METs achieved by patients with CKD. Exercise capacity was reduced in patients with CKD, presumably consequent to diastolic dysfunction. Elevated exercise E/e' in patients with CKD is an independent predictor of cardiovascular death and MACE. (C) 2020 by the American College of Cardiology Foundation.