question: List the types of the Cardiorenal syndrome (CRS) according to the five-part classification system.
answer: Cardiorenal syndromes (CRS) have been recently classified into five distinct entities, each with different major pathophysiologic mechanisms. 
  CRS type 1: acute worsening of heart function (AHF-ACS) leading to kidney injury and/or dysfunction. 
  CRS type 2: chronic abnormalities in heart function (CHF-CHD) leading to kidney injury or dysfunction. 
  CRS type 3: acute worsening of kidney function (AKI) leading to heart injury and/or dysfunction. 
  CRS type 4: chronic kidney disease (CKD) leading to heart injury, disease and/or dysfunction. 
  CRS type 5: systemic conditions leading to simultaneous injury and/or dysfunction of heart and kidney.