Kolluri, Nikhil

Abstract Background Cardiac sarcoidosis (CS) is an infiltrative inflammatory condition defined by infiltration of noncaseating granulomas into the heart. Based on the location of sarcoid lesion involvement, patients can present with symptoms of congestive heart failure, arrhythmias, and even sudden cardiac death. Purpose Diagnosis of CS has been somewhat challenging, with the Heart Rhythm Society (HRS) and Japanese Ministry of Health and Welfare (JMHW) being the 2 widely accepted diagnostic guidelines. Endomyocardial biopsy is the gold standard to prove definite CS but has a low sensitivity. Imaging studies have been helpful as non-invasive methods to diagnose probable CS but these can be logistically difficult and expensive. Thus, investigating for laboratory biomarkers that can act as both diagnostic and prognostic can be crucial in how we diagnose and manage CS in the future. Methods Patients meeting HRS for CS were evaluated at a single institution (n=217). Biomarkers of interest included angiotensin-converting enzyme (ACE), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), N-terminal pro B-type natriuretic peptide (NT-proBNP), troponin-T, 1,25 dihydroxyvitamin D (1,25-OHVit-D), and creatinine. Biomarkers were stratified by clinical variables of interest and their association with prognosis was examined. The primary endpoint was LVAD implantation, transplantation, or death. Results 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, 1,25-OHVit-D 55.5±20, and creatinine 1.12±0.3. None of the biomarkers differed by sex, definite or probable CS, or a history of immunosuppression. 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 (52/217 patients). Biomarkers associated with long term outcomes in patients with cardiac sarcoidosis Biomarker Hazard ratio P value Troponin-T 1.06 (1.02–1.11)* 0.006 NT-pro BNP 1.31 (1.15–1.48)** 0.0003 Creatinine 4.02 (1.41–9.94)*** 0.01 *Per 0.01 ng/mL change; 99th percentile upper reference limit <0.01 ng/mL; **per 1,000 pg/mL change; ***per 1 mg/dL change. Conclusion Troponin-T, NT-proBNP, and creatinine at presentation predict outcomes in patients with CS. Further investigation on the utility of biomarkers for assessment of disease activity and treatment response is warranted.

Abstract Background Patients with type 2 diabetes are at an increased risk of cardiovascular events compared to individuals without diabetes. The role glycemic control plays in reducing cardiovascular risk remains uncertain. Coronary microvascular dysfunction (CMD) is more frequent in women compared to men, is prevalent in patients with type 2 diabetes and is linked to adverse cardiovascular events. We compared the association between CMD and glycemic control across sexes in patients with chest pain and non-obstructive coronary artery disease (CAD). Methods Patients with chest pain who were found to have non-obstructive CAD (stenosis <40%) at angiography underwent an invasive assessment of endothelial-independent and endothelial–dependent coronary microvascular function. Using a Doppler guidewire, endothelial-independent microvascular function was assessed by measuring the coronary flow velocity in response to intracoronary adenosine and comparing this to baseline to calculate the coronary flow reserve ratio (CFRAdn). A CFRAdn ≤2.5 was considered abnormal. Endothelial-dependent microvascular function was assessed by measuring the percent change in coronary blood flow in response to intracoronary infusions of acetylcholine (%ΔCBFAch), with a %ΔCBFAch ≤50% considered abnormal. Patients were classified as having normal versus abnormal CFRAdn and %ΔCBFAch. Measurements of HbA1c and fasting serum glucose were obtained at the time of catheterization and compared between groups after stratification by sex. Results Between 1993 and 2012, 1,469 patients (mean age 50.4 years, 35% male) underwent coronary angiography and invasive testing for CMD, of which 129 (8.8%) had type 2 diabetes. Fifty one (39.5%) had an abnormal %ΔCBFAch and 49 (38.0%) had an abnormal CFRAdn. Conventional cardiovascular risk factors did not vary significantly between groups. Females with an abnormal CFRAdn or abnormal %ΔCBFAch had a significantly higher HbA1c compared to those with a normal CFRAdn or %ΔCBFAch respectively: HbA1c % (standard deviation) 7.4 (2.1) vs. 6.5 (1.1), p=0.035 and 7.3 (1.9) vs. 6.4 (1.2), p=0.022, respectively. Females with an abnormal CFRAdn had significantly higher fasting serum glucose concentrations compared to those with a normal CFRAdn: fasting serum glucose mg/dL (standard deviation) 144.4 (55.6) vs. 121.9 (28.1), p=0.035. These effects were not observed in men. Amongst female diabetics, a higher HbA1c was significantly associated with any CMD after adjusting for covariates: odds ratio (95% confidence interval) 1.69 (1.01 – 2.86) p=0.049; and a fasting serum glucose >140 mg/dL was significantly associated with an abnormal CFRAdn, 4.28 (1.43–12.81). Conclusion Poor glycemic control is associated with CMD in females with diabete who present with chest pain and non-obstructive CAD. These findings highlight the importance of sex-specific risk stratification models and treatment strategies when managing cardiovascular risk in diabetics. Acknowledgement/Funding Mayo Foundation