Up to 19% of patients with a chronic form of cardiorenal syndrome will subsequently develop an acute syndrome. Development of acute or type 4 cardiorenal syndrome is independently associated with mortality, the acute form having the worst prognosis.

Background/Aims: Chronic kidney disease (CKD) is common among patients with heart failure with preserved ejection fraction (HFpEF) and is associated with worse clinical outcomes. This study aims to identify whether the association of CKD with HFpEF is independent of underlying echocardiographic abnormalities. Materials: We conducted a retrospective cohort study including patients without prevalent heart failure referred for echocardiography. Patients with serial echocardiograms, baseline left ventricular ejection fraction (LVEF) ≥50% and estimated glomerular filtration rate (eGFR) ≥90 mL/min/1.73 m2 were matched 1:1 with patients with eGFR <60 mL/min/1.73 m2 for age (±5 years), sex, history of hypertension or diabetes, use of renin-angiotensin inhibitors, and LVEF (±5%). A secondary analysis included patients with preserved LVEF and normal left ventricular mass index matched for the same parameters except use of renin-angiotensin inhibitors. Results: Patients with CKD were at increased risk for HFpEF admission: crude hazard ratio (HR) 1.79 (95% confidence interval [CI] 1.38–2.32, p < 0.001) and adjusted HR (for coronary disease, loop diuretics, left atrial diameter) 1.64 (95% CI 1.22–2.21, p = 0.001). LVEF and left ventricular diameter decreased over time in both groups but no difference was observed in rate of dropping. Results were similar in the secondary analysis (crude HR 1.99, 95% CI 1.07–3.71, p = 0.03 and HR adjusted for left atrial diameter 1.98, 95% CI 1.05–3.75, p = 0.04). Rate of change was similar for LVEF, pulmonary artery pressure, and left ventricular mass index in both groups. Conclusion: CKD is independently associated with incident HFpEF despite a similar change in relevant echocardiographic parameters in patients with or without CKD.