Cardiorenal Syndrome

The definition of cardiorenal syndrome is “any acute or chronic problem in the heart or kidneys that could result in an acute or chronic problem in the other.” The term describes multiple underlying subtypes, which subdivide according to the underlying triggering pathology and chronicity. Cardiorenal syndrome is classified into 5 subtypes based on underlying pathophysiology and chronicity. Dysfunction or failure of 1 organ—either the heart or the kidney—can significantly affect the function of the other. Additionally, both organs can be affected in numerous systemic diseases. Identifying patients at high risk of developing cardiorenal syndrome before significant organ damage occurs remains a challenge. Current biomarkers, such as serum creatinine, have limitations in the early detection of kidney injury, as they lag behind the actual injury. Research is ongoing to find more sensitive and specific cardiorenal biomarkers.  Further, there is a lack of standardized, evidence-based treatment algorithms specifically for cardiorenal syndrome. Managing volume overload while preserving renal function is a delicate balance, and diuretic resistance is a common complication. The optimal use of neurohormonal blockade (eg, renin-angiotensin-aldosterone system inhibitors, beta-blockers, mineralocorticoid receptor antagonists) is often limited by concerns about worsening renal function or electrolyte imbalances such as hyperkalemia. Many treatment strategies for cardiorenal syndrome are extrapolated from heart failure or chronic kidney disease trials, and these trials often exclude or do not specifically focus on patients with both conditions. There is a need for dedicated clinical trials to evaluate the efficacy and safety of specific interventions in this population. This activity outlines the clinical presentation, diagnostic evaluation, and management strategies for patients with cardiorenal syndrome, highlighting the critical role of the interprofessional healthcare team in the coordinated management of this disease. Each subtype of cardiorenal syndrome involves a unique pathophysiology, and thus, the management for each subtype differs.