Role of renal function and cardiac biomarkers (NT-proBNP and Troponin) in determining mortality and cardiac outcome in atheromatous renovascular disease.Kidney Blood Press Res. 2009; 32(5):373-9.KB
BACKGROUND AND AIMS
Patients with atheromatous renovascular disease (ARVD) have high cardiovascular morbidity and mortality. The cardiac markers N-terminal pro-brain natriuretic peptide (NT-proBNP) and troponin (cTnT) are easily measured, yet not widely used in renal patients as they are thought to be inaccurate in renal disease. We aimed to see if these markers could be used as prognostic indicators of cardiovascular events (CVEs) and death in ARVD.
Subjects with ARVD treated in 1 renal center in 2003 were prospectively followed up. NT-proBNP and cTnT at baseline were correlated with CVEs and death, echocardiographic findings and degree of renal artery stenosis. Cutoff levels of 0.03 ng/ml (cTnT) and 43 pmol/l (NT-proBNP) were used.
Eighty-two patients (mean +/- SD age 69 +/- 8 years, mean follow-up 40.2 +/- 16.6 months) were suitable for analysis. Twenty-nine percent of patients suffered new CVEs, and 37.8% died. Renal function was a significant predictor of CVEs and death. Patients with a raised NT-proBNP were more likely to die than those in the same chronic kidney disease (CKD) category with normal levels (p < 0.0001) even after adjusting for multivariate factors (hazard ratio 8.3 for high proBNP vs. 3.6 for low proBNP in CKD stage 4-5).
No study to our knowledge has looked at both NT-proBNP and cTnT as outcome markers in ARVD. Our study shows that renal function is more important as a marker of suffering a CVE. However, raised NT-proBNP is associated with a greater likelihood of death when subdivided by CKD stage. Early risk stratification by simple measurement of these biomarkers may aid in intensifying management in high-risk patients, although further studies to assess the value of this approach are warranted.