ABSTRACT
BACKGROUND: MicroRNAs (miRs) regulate gene expression and play an important role in ventricular and vascular remodeling. However, there are limited data regarding their role in heart failure with preserved ejection fraction (HFpEF). The aim of this study was to assess gene expression of miR-1, miR-133a, miR-21, miR-208b, miR-499, and miR-26b in peripheral blood mononuclear cells (PBMCs) in hypertensive patients with HFpEF and to evaluate their association with their exercise capacity. METHODS: We included 56 hypertensive patients with HFpEF (age 67.29 ± 7.75 years). Forty-two hypertensive patients without HFpEF (age 66.83 ± 7.17 years) served as controls. All subjects underwent a cardiopulmonary exercise test (CPXT). PBMCs were isolated and levels of miRs were determined by quantitative real-time reverse transcription polymerase chain reaction. RESULTS: For hypertensive patients with HFpEF, higher expression levels in PBMCs were found only for miR-26b (7.6 ± 7.3 vs. 4.0 ± 3.6, P = 0.002), miR-208b (28.8 ± 35.3 vs. 7.5 ± 13.3, P < 0.001), and miR-499 (14.2 ± 22.4 versus 3.5 ± 2.9, P = 0.001). The strongest correlations with CPXT parameters were found for miR-208b levels, which had a positive correlation with maximal oxygen uptake (peakVO2) (r = 0.671, P < 0.001), exercise duration (r = 0.445, P = 0.001), and minute ventilation-carbon dioxide production relationship (VE/VCO2) (r = 0.437, P = 0.001) in the HFpEF group. CONCLUSIONS: miR-26b, miR-208b, and miR-499 show a distinct in profile in hypertensive patients with HFpEF that is related with functional capacity. Further studies are needed to assess the role of miRs as prognostic tools or as therapeutic targets in those patients.
Subject(s)
Heart Failure/physiopathology , Hypertension/physiopathology , Leukocytes, Mononuclear/chemistry , MicroRNAs/physiology , Stroke Volume/physiology , Aged , Biomarkers , Exercise Test , Female , Humans , Male , MicroRNAs/blood , Middle Aged , Oxygen ConsumptionABSTRACT
BACKGROUND: Platelet activation is crucial in the development of stent thrombosis following percutaneous coronary intervention (PCI). We carried out a long-term assessment of multiple factors implicated in the thrombotic process and monitored markers of platelet activation after the implantation of sirolimus-eluting stents (SES) in patients with stable coronary artery disease (CAD). Additionally, we compared these findings with those after bare-metal stent (BMS) implantation. METHODS: A cohort of 47 consecutive patients, aged <70 years, with severe stenosis (>70% narrowing of the lumen) of one major epicardial coronary artery and stable CAD underwent successful elective PCI. Patients were randomly allocated to SES (n = 25) or BMS (n = 22). Venous blood was obtained 24 hours before and 24 hours, 48 hours, 1 month, and 6 months after PCI for measurements of plasma levels of sP-selectin, von Willebrand Factor (vWF), fibrinogen, d-dimer, sCD40, factor VIII, b-thromboglobulin (b-TG) and platelet factor 4 (PF-4). RESULTS: There were no significant differences between the two groups in levels of fibrinogen or d-dimers in peripheral blood. However, we observed a significant kinetic effect (p<0.001) and stent-effect (p<0.015) on vWF levels and a significant kinetic effect (p = 0.012) on factor VIII, sP-selectin (p = 0.04), b-TG (p<0.001), and PF4 (p = 0.016). A trend towards a significant stent effect on sCD40 was also detected (p = 0.06). CONCLUSIONS: SES and BMS did not show significant differences in relationship to markers of platelet activation and coagulation in patients with stable CAD. Although some markers showed an increase after stent implantation, they returned to the initial levels 6 months later.