Troponin-T, NT-proBNP, and Serum Creatinine at Presentation Predict Outcomes in Patients with Cardiac Sarcoidosis

Abstract

BackgroundCardiac sarcoidosis (CS) is an uncommon inflammatory cardiomyopathy for which biomarkers have not been well characterized. The aim of this study was to evaluate biomarkers that could be useful for monitoring disease activity and predict outcomes in CS.MethodsPatients meeting Heart Rhythm Society criteria for definite and probable CS were evaluated at a single institution (n=232). Angiotensin-converting enzyme (ACE), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), B-type natriuretic peptide (BNP), N-terminal pro B-type natriuretic peptide (NT-proBNP), troponin-T, and creatinine levels among others at presentation were recorded. Biomarkers were stratified by clinical and radiologic variables of interest and evaluated against a primary composite end point of LVAD implantation, heart transplantation, or death and a secondary endpoint of hospitalization free survival.ResultsMean values on presentation were: ACE 32.9±28, ESR 12±13, CRP 7.4±19, NT-proBNP 1630±2923, Troponin-T 0.03±0.1, and creatinine 1.12±0.3. ACE levels were associated with the presence of cardiac fibrosis on cardiac MRI (mean difference 14.7, p=0.032). Troponin-T (p=0.006; HR 1.06 per 0.01 ng/mL), NT-proBNP (p=0.0003; HR 1.31 per 1,000 pg/mL), and creatinine (p=0.01; HR 4.02 per mg/dL) were each associated with the primary endpoint (Table 1). After adjustment for preserved versus reduced ejection fraction, NT-proBNP (HR 1.3, CI 1.1-1.5, p = 0.0004), Troponin-T (HR 1.06, CI 1.02-1.1, p = 0.005), and creatinine (HR 4.2, CI 1.5-10.3, p = 0.009) were still associated with the endpoint, confirming the utility of using these biomarkers to predict outcomes despite EF. NT-proBNP, BNP, creatinine, albumin, and calcium were associated with the secondary endpoint (p<0.05). Detectable troponin level (>0.01) and NT-proBNP > 700 were associated with increased hazard over time; HR 4.3 (CI 1.1 - 17.2), p = 0.03 and HR 3.6 (CI 1.3 - 9.9), p = 0.009, respectively (Figure 1).ConclusionTroponin-T, NT-proBNP, and creatinine at presentation predict outcomes in patients with CS, while ACE levels are associated with MRI fibrosis. Further investigation on the utility of biomarkers for assessment of disease activity and treatment response is warranted. Cardiac sarcoidosis (CS) is an uncommon inflammatory cardiomyopathy for which biomarkers have not been well characterized. The aim of this study was to evaluate biomarkers that could be useful for monitoring disease activity and predict outcomes in CS. Patients meeting Heart Rhythm Society criteria for definite and probable CS were evaluated at a single institution (n=232). Angiotensin-converting enzyme (ACE), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), B-type natriuretic peptide (BNP), N-terminal pro B-type natriuretic peptide (NT-proBNP), troponin-T, and creatinine levels among others at presentation were recorded. Biomarkers were stratified by clinical and radiologic variables of interest and evaluated against a primary composite end point of LVAD implantation, heart transplantation, or death and a secondary endpoint of hospitalization free survival. Mean values on presentation were: ACE 32.9±28, ESR 12±13, CRP 7.4±19, NT-proBNP 1630±2923, Troponin-T 0.03±0.1, and creatinine 1.12±0.3. ACE levels were associated with the presence of cardiac fibrosis on cardiac MRI (mean difference 14.7, p=0.032). Troponin-T (p=0.006; HR 1.06 per 0.01 ng/mL), NT-proBNP (p=0.0003; HR 1.31 per 1,000 pg/mL), and creatinine (p=0.01; HR 4.02 per mg/dL) were each associated with the primary endpoint (Table 1). After adjustment for preserved versus reduced ejection fraction, NT-proBNP (HR 1.3, CI 1.1-1.5, p = 0.0004), Troponin-T (HR 1.06, CI 1.02-1.1, p = 0.005), and creatinine (HR 4.2, CI 1.5-10.3, p = 0.009) were still associated with the endpoint, confirming the utility of using these biomarkers to predict outcomes despite EF. NT-proBNP, BNP, creatinine, albumin, and calcium were associated with the secondary endpoint (p<0.05). Detectable troponin level (>0.01) and NT-proBNP > 700 were associated with increased hazard over time; HR 4.3 (CI 1.1 - 17.2), p = 0.03 and HR 3.6 (CI 1.3 - 9.9), p = 0.009, respectively (Figure 1). Troponin-T, NT-proBNP, and creatinine at presentation predict outcomes in patients with CS, while ACE levels are associated with MRI fibrosis. Further investigation on the utility of biomarkers for assessment of disease activity and treatment response is warranted.