Table 1: Classification of cardiorenal syndorme (CRS).

Acute cardiorenal syndrome CRS type 1 Abrupt worsening of cardiac function leading to acute kidney injury (AKI) Chronic cardiorenal syndrome CRS type 2 Chronic abnormalities in cardiac function causing progressive chronic kidney disease (CKD) Acute renocardiac syndrome CRS type 3 Sudden worsening of renal function causing acute cardiac dysfunction Chronic renocardiac syndrome CRS type 4 Condition of primary CKD leading to an impairment of the cardiac function (ventricular hypertrophy, diastolic dysfunction) and/or increased risk of adverse cardiovascular events. Secondary cardiorenal syndrome CRS type 5 Systemic disorders (e.g., sepsis) causing both cardiac and renal dysfunction