From the Guidelines
Cystatin C is not recommended as a primary marker for diagnosing or managing acute heart failure, and instead, natriuretic peptides (BNP or NT-proBNP) are the preferred biomarkers, as supported by the most recent and highest quality study 1. The use of cystatin C as a marker in acute heart failure is not established, and its role is limited to assessing kidney function and providing prognostic information in heart failure patients.
Key Points
- Natriuretic peptides (BNP or NT-proBNP) have stronger evidence supporting their use in acute heart failure diagnosis and management, with established cutoff values for diagnosis (BNP >100 pg/mL or NT-proBNP >300 pg/mL) 1.
- Cystatin C may have value as an adjunctive marker, particularly in assessing cardiorenal syndrome or predicting outcomes in heart failure patients with kidney dysfunction, as it is less affected by age, sex, and muscle mass compared to creatinine.
- Clinicians should rely primarily on natriuretic peptides, clinical assessment, and imaging studies when diagnosing and managing acute heart failure, as recommended by major clinical guidelines 1.
Clinical Considerations
- The diagnosis of acute heart failure is often challenging, and confirmatory testing is required in many cases.
- The early use of natriuretic peptide tests can reliably exclude heart failure and allow more rapid investigation of other potential causes for a patient’s symptoms.
- A negative test result may reduce or obviate the need to proceed to echocardiography or other cardiac imaging, allowing more efficient use of resources.
Recommendations
- Use natriuretic peptides (BNP or NT-proBNP) as the primary biomarkers for diagnosing and managing acute heart failure, rather than cystatin C.
- Consider using cystatin C as an adjunctive marker in specific cases, such as assessing cardiorenal syndrome or predicting outcomes in heart failure patients with kidney dysfunction.
- Always interpret test results in the clinical context, taking into account the patient's symptoms, medical history, and other diagnostic findings.
From the Research
Guidelines for Using Cystatin as a Marker in Acute Heart Failure
- Cystatin C is considered a good prognostic marker in heart failure, as evidenced by studies such as 2 and 3.
- The prognostic value of cystatin C in acute heart failure is independent of other markers of renal function and NT-proBNP, as shown in 3.
- Elevated cystatin C levels are associated with increased mortality and adverse outcomes in patients with acute heart failure, as demonstrated in 2, 3, and 4.
- Cystatin C may be a preferred biomarker in the assessment of patients with acute heart failure and slightly impaired renal function, according to 2.
- The combination of cystatin C and other biomarkers, such as NT-proBNP, can improve risk stratification in acute heart failure, as suggested by 3.
Key Findings
- A cystatin C level above 1.25mg/dL is associated with a higher mortality rate in patients with acute heart failure, as found in 2.
- Cystatin C is a strong and independent predictor of outcome at 12 months in acute heart failure, as reported in 3.
- Elevated cystatin C levels are associated with increased risk of death and rehospitalization in patients with heart failure, as shown in 4 and 5.
Clinical Implications
- Cystatin C can be used as a prognostic marker in acute heart failure, particularly in patients with normal or slightly impaired renal function, as suggested by 2 and 3.
- The measurement of cystatin C can provide additional prognostic information beyond traditional markers of renal function, such as creatinine, as demonstrated in 5 and 6.
- Cystatin C may be useful in identifying patients with acute heart failure who are at increased risk for adverse cardiovascular events, as reported in 6.