Top Things to Know: Cardiorenal Syndrome: Classification, Pathophysiology, Diagnosis, and Treatment Strategies

Published: March 11, 2019

  1. Cardiorenal syndrome encompasses a spectrum of disorders involving both the heart and kidneys in which acute or chronic dysfunction in one organ may induce acute or chronic dysfunction in the other organ. It represents the confluence of heart-kidney interactions across several interfaces causing a series of complex disease states.
  2. The overlap of cardiovascular and kidney disease extends across several interfaces. These include the hemodynamic interactions of the heart and kidney in heart failure (HF), the impact of atherosclerotic disease across both organ systems, neurohormonal activation, cytokines, the biochemical perturbations across the anemia–inflammation–bone mineral axis in chronic kidney disease (CKD), and structural changes in the heart unique to kidney disease progression.
  3. This scientific statement focuses on the definition of CRS, the pathophysiology of and the diagnostic and therapeutic strategies in CRS. It also describes the cardiorenal interactions in special populations such as patients with diabetes mellitus (DM) and kidney transplant (KT) recipients.
  4. Diagnostic strategies in CRS are discussed: biomarkers, imaging modalities, and volume status determination in CRS.
  5. Biomarkers are explored as they apply to the clinical context of CRS. They represent a new dimension in the diagnostic algorithm in evaluating HF with impaired kidney function and offer prognostic value in acute and chronic CRS. Biomarker areas are discussed encompassing both the heart and kidney.
  6. Treatment strategies in CRS include decongestive therapies (diuretics) and ultrafiltration.
  7. Neurohormonal modulation pertaining to vasodilators and inotropic therapies are reviewed in this paper. Renin-angiotensin-aldosterone system (RAAS) in chronic CRS including angiotensin-converting enzyme inhibitors/ARBs and associated treatments are presented in this paper.
  8. Cardiovascular disease is a major cause of mortality in persons with type 2 diabetes mellitus (DM). Cardiorenal outcomes in persons with type2 DM are examined as they relate to safety and cardiovascular outcomes of the major novel classes of antidiabetic therapies.
  9. There is a need for comprehensive trial endpoints including Major Adverse Renal and Cardiac Events (MARCE - acute kidney injury, stroke, myocardial infarction, hospitalization, renal replacement [(dialysis]), progression of chronic kidney disease, HF and death. There is the need for a dedicated cardiorenal education track (multidisciplinary) that includes both clinical and research needs in the field for the future (cross-training among nephrology, cardiology fellows, and nursing and allied healthcare providers).
  10. Cardiorenal syndrome is a complex condition where multidisciplinary provider collaboration is necessary to optimize diagnosis and treatment, and to enhance patient outcomes.


Rangaswami J, Bhalla V, Blair JEA, Chang TI, Costa S, Lentine KL, Lerma EV, Mezue K, Molitch M, Mullens W, Ronco C, Tang WHW, McCullough PA; on behalf of the American Heart Association Council on the Kidney in Cardiovascular Disease and Council on Clinical Cardiology. Cardiorenal syndrome: classification, pathophysiology, diagnosis, and treatment strategies: a scientific statement for healthcare professionals from the American Heart Association [published online ahead of print March 11, 2019]. Circulation. doi: 10.1161/CIR.0000000000000664.