Table 4.

Cardiorenal syndrome classification system – adapted from reference (111)

Classification	Abbreviation	Characteristic	Primary Event	Secondary Event	Criteria for primary/secondary Events
Acute cardio-renal syndrome	CRS type1	Abrupt worsening of cardiac function leading to AKI	AHF, ACS cardiogenic shock	AKI	ESC,AHA,ACC/RIFLE-AKIN
Chronic cardio-renal syndrome	CRS type2	Chronic worsening of cardiac function leading to progressive and permanent chronic kidney disease	CHD	CKD	ESC,AHA,ACC/ KDOQI
Acute reno-cardiac syndrome	CRS type3	AKI causing acute cardiac dysfunction	AKI	AHF, ACS arrhythmias shock	RIFLE-AKIN/ ESC,AHA,ACC
Chronic reno-cardiac syndrome	CRS type4	CKD leading to impairment of cardiac function and/or increased risk of adverse cardiovascular events	CKD	CHD, AHF ACS	KDOQI/ESC,AHA,ACC
Secondary cardio-renal syndrome	CRS type5	Systemic disorders causing both cardiac and renal dysfunction (i.e. septic shock, vasculitis)	Systemic disease (i.e. sepsis)	AKI, CKD AHF, CHD ACS	Disease specific criteria/RIFLE-AKIN, ESC, AHA, ACC,KDOQI

AKI= acute kidney injury, CKD=chronic kidney disease, ACS= acute coronary syndrome, AHF=acute heart failure, CHD=chronic heart disease,