Table 2.

Summary of cardio-renal syndromes (CRS) phenotypes [117].

CRS Type	Denomination	Description	Model
I	Acute Cardio-renal	Acute cardiac decompensation leads to acute kidney injury which can be reversible	Acute coronary syndrome/acute HF triggering acute kidney failure
II	Chronic Cardio-renal	Chronic cardiac dysfunction leads to progressive chronic kidney dysfunction which is mostly irreversible	Chronic heart failure causing chronic kidney disease
III	Acute Reno-cardiac	Abrupt primary kidney dysfunction leads to acute cardiac dysfunction	Acute glomerulonephritis instigating acute HF
IV	Chronic Reno-cardiac	Primary kidney dysfunction leads to cardiac impairment	Chronic kidney disease causing coronary artery disease/diastolic heart dysfunction
V	Secondary Cardio-renal	Acute/chronic systemic disease leading to combined cardiac and kidney dysfunction	Sepsis, vasculitis, diabetes mellitus, amyloidosis