Brandon Gray

Circulating Progenitor Cells Identify Peripheral Arterial Disease in Patients With Coronary Artery Disease

RATIONALE Peripheral arterial disease (PAD) is a clinical manifestation of extracoronary atherosclerosis. Despite sharing the same risk factors, only 20% to 30% of patients with coronary artery disease (CAD) develop PAD. Decline in the number of bone marrow-derived circulating progenitor cells (PCs) is thought to contribute to the pathogenesis of atherosclerosis. Whether specific changes in PCs differentiate patients with both PAD and CAD from those with CAD alone is unknown. OBJECTIVE Determine whether differences exist in PCs counts of CAD patients with and without known PAD. METHODS AND RESULTS 1497 patients (mean age: 65 years; 62% men) with known CAD were identified in the Emory Cardiovascular Biobank. Presence of PAD (n=308) was determined by history, review of medical records, or imaging and was classified as carotid (53%), lower extremity (41%), upper extremity (3%), and aortic disease (33%). Circulating PCs were enumerated by flow cytometry. Patients with CAD and PAD had significantly lower PC counts compared with those with only CAD. In multivariable analysis, a 50% decrease in cluster of differentiation 34 (CD34+) or CD34+/vascular endothelial growth factor receptor-2 (VEGFR2+) counts was associated with a 31% (P=0.032) and 183% (P=0.002) increase in the odds of having PAD, respectively. CD34+ and CD34+/VEGFR2+ counts significantly improved risk prediction metrics for prevalent PAD. Low CD34+/VEGFR2+ counts were associated with a 1.40-fold (95% confidence interval, 1.03-1.91) and a 1.64-fold (95% confidence interval, 1.07-2.50) increases in the risk of mortality and PAD-related events, respectively. CONCLUSIONS PAD is associated with low CD34+ and CD34+/VEGFR2+ PC counts. Whether low PC counts are useful in screening for PAD needs to be investigated.

Depression and chest pain in patients with coronary artery disease

BACKGROUND Depression is common in patients with coronary artery disease (CAD) and is associated with more frequent chest pain. It is however unclear whether this is due to differences in underlying CAD severity. We sought to determine [1] whether depressive symptoms are associated with chest pain independently of CAD severity, [2] whether improvement in depressive symptoms over time is associated with improvement in chest pain and [3] whether the impact of revascularization on chest pain differs between patients with and without depression. METHODS AND RESULTS 5158 patients (mean age 63±12years, 65% male, 20% African American) undergoing cardiac catheterization completed the Seattle Angina Questionnaire (SAQ) and Patient Health Questionnaire-8 (PHQ-8) to assess angina severity and screen for depression, respectively, both at baseline and between 6 and 24months of follow-up. We found significant correlations between PHQ-8 scores and angina frequency (SAQ-AF, r=-0.28), physical limitation (SAQ-PL, r=-0.32) and disease perception (SAQ-DS r=-0.37, all P<0.001), which remained significant after adjustment for clinical characteristics, CAD severity, and anti-depressant use. Improvement in depressive symptoms at follow-up was associated with improvement in angina subscales (SAQ-AF β 1.34, P<0.001), SAQ-PL β 1.85, P<0.001), and SAQ-DS (β 2.12, P<0.001), independently of CAD severity or revascularization. Patients with depression who underwent revascularization had less improvement in chest pain frequency than those without depressive symptoms. CONCLUSIONS Depression is associated with angina, independently of CAD severity. Patients with depression may not derive as adequate symptomatic benefit from revascularization as those without. Whether treatment of underlying depression improves chest pain needs to be further studied.

Bioactive Lipids and Circulating Progenitor Cells in Patients with Cardiovascular Disease

Bone marrow‐derived progenitor cells are mobilized into the peripheral blood after acute myocardial injury and in chronic ischemic heart disease. However, the mechanisms responsible for this mobilization are poorly understood. We examined the relationship between plasma levels of bioactive lipids and number of circulating progenitor cells (CPCs) in patients (N = 437) undergoing elective or emergent cardiac catheterization. Plasma levels of sphingosine‐1 phosphate (S1P) and ceramide‐1 phosphate (C1P) were quantified using mass spectrometry. CPCs were assessed using flow cytometry. S1P levels correlated with the numbers of CD34+, CD34+/CD133+, and CD34+/CXCR4+ CPCs even after adjustment for potential confounding factors. However, no significant correlation was observed between C1P levels and CPC count. Plasma levels of S1P correlated with the number of CPCs in patients with coronary artery disease, suggesting an important mechanistic role for S1P in stem cell mobilization. The therapeutic effects of adjunctive S1P therapy to mobilize endogenous stem cells need to be investigated. Stem Cells Translational Medicine 2017;6:731–735

Cardiovascular Disease Biomarkers and suPAR in Predicting Decline in Renal Function: A Prospective Cohort Study

Introduction Soluble urokinase-type plasminogen activator receptor (suPAR) strongly predicts outcomes and incident chronic kidney disease (CKD) in patients with cardiovascular disease (CVD). Whether the association between suPAR and CKD is a reflection of its overall association with chronic inflammation and poor CVD outcomes is unclear. We examined whether CVD biomarkers, including high-sensitivity C-reactive protein (hs-CRP), fibrin-degradation products (FDPs), heat-shock protein 70 (HSP-70), and high-sensitivity troponin I (hs-TnI) were associated with a decline in kidney function in the Emory Cardiovascular Biobank cohort, in which suPAR levels were shown to be predictive of both incident CKD and CVD outcomes. Methods We measured suPAR, hs-CRP, HSP-70, FDP, and hs-TnI plasma levels in 3282 adults (mean age 63 years, 64% male, 75% estimated glomerular filtration rate [eGFR] >60 ml/min per 1.73 m2). Glomerular filtration rate was estimated using Chronic Kidney Disease–Epidemiology Collaboration (eGFR) at enrollment (n = 3282) and follow-up (n = 2672; median 3.5 years). Urine protein by dipstick at baseline was available for 1335 subjects. Results There was a weak correlation among biomarkers (r range: 0.17−0.28). hs-CRP, FDPs, hs-TnI, and suPAR were independently associated with baseline eGFR and proteinuria. The median yearly decline in eGFR was −0.6 ml/min per 1.73 m2. hs-CRP (β: −0.04; P = 0.46), FDPs (β: −0.13; P = 0.08), HSP-70 (β: 0.05; P = 0.84), or hs-TnI (β: −0.01; P = 0.76) were associated with eGFR decline. suPAR remained predictive of eGFR decline even after adjusting for all biomarkers. Discussion hs-CRP, FDP, HSP-70, and hs-TnI were not associated with eGFR decline. The specific association of suPAR with eGFR decline supported its involvement in pathways specific to the pathogenesis of kidney disease.

VITAMIN D3 LEVELS MODULATE CXCR4+ CIRCULATING PROGENITOR CELL COUNTS

The role of 1,25-dihydroxy-vitamin D3 (VitD3) in cardiovascular disease remains controversial. Vitamin D receptors on progenitor cells (PCs) promote maturation and vascular repair by inducing SDF1 expression and homing of CXCR4+ angiogenic myeloid cells. Whether VitD3 levels modulate circulating PCs

HIGH-SENSITIVITY TROPONIN-I LEVELS PREDICT LONG-TERM MORTALITY INDEPENDENT OF CORONARY ARTERY DISEASE SEVERITY

High-sensitivity Troponin-I (hs-TnI) as a marker of myocardial injury is predictive of adverse outcomes in patients with coronary artery disease (CAD). Whether the relationship between hs-TnI and outcomes is dependent on underlying CAD severity is unknown. 2826 patients without AMI (mean age 62, 64