Lipoprotein-associated phospholipase A2, a novel cardiovascular inflammatory marker, in HIV-infected patients.

BACKGROUND: Lipoprotein-associated phospholipase A2 (Lp-PLA2) is an emerging biomarker of cardiovascular disease. This study was conducted to describe the distribution of Lp-PLA2 in a cohort of human immunodeficiency virus (HIV)-infected adults and to determine associations between Lp-PLA2, cardiometabolic risk factors, and subclinical atherosclerosis in this population. METHODS: Lp-PLA2 was assessed in 341 (25% women, 52% white, 74% on highly active antiretroviral therapy [HAART]) participants of a cohort with detailed characterization of atherogenic risk factors, including surrogate markers of carotid and coronary atherosclerosis. RESULTS: Mean Lp-PLA2 mass was 313 ± 105 ng/mL and activity 173 ± 49 nmol/minute/mL. Seventy-five percent of participants had abnormal Lp-PLA2. Those in the highest Framingham Risk Score tertile had significantly higher Lp-PLA2 activity. Participants with abnormal carotid intima-media thickness (cIMT) had higher Lp-PLA2 mass and activity. Those with coronary artery calcium (CAC) scores >100 had significantly higher Lp-PLA2 mass than those with lower or nondetectable calcium. Those on HAART and protease inhibitor (PI)-based treatment had significantly higher Lp-PLA2 mass and activity than those who were treatment-naive or not on PIs. In multivariate regression, HAART and PI use were positively associated with Lp-PLA2 activity and mass after adjusting for age, race, sex, low-density and high-density lipoprotein cholesterol levels, triglyceride level, and smoking. Adding Lp-PLA2 activity tertiles to the model improved the predictive value for abnormal common cIMT, but not internal cIMT or CAC score. CONCLUSIONS: Lp-PLA2 is highly abnormal in HIV-infected patients and is associated with several cardiovascular and HIV treatment-specific risk factors. Lp-PLA2 may be used as an additional and more vascular specific biomarker for cardiovascular risk stratification in HIV-positive patients.

Evaluation of myocardial mechanics with three-dimensional speckle tracking echocardiography in heart transplant recipients: comparison with two-dimensional speckle tracking and relationship with clinical variables.

AIMS: Two-dimensional speckle-tracking echocardiography (2D-STE) is limited by its inability to track tissue motion in three dimensions. This is particularly relevant in heart transplant recipients, in whom marked translational motion of the transplanted heart is present. We aimed to compare 3-dimensional (3D)- and 2D-STE-derived strain parameters, and to identify clinical features associated with myocardial mechanics in transplant recipients. METHODS AND RESULTS: In 36 heart transplant recipients, global and regional left-ventricular (LV) longitudinal and circumferential strain (LSt and CSt), and radial displacement (RDisp) were obtained by 3D- and 2D-STE, and their results were compared. 3D-STE deformation from a subset of transplant recipients with preserved ejection fraction was compared with a control group of 25 subjects matched by gender, age, history of hypertension, and ejection fraction. Associations between global LSt and CSt and clinical, echocardiographic, and haemodynamic parameters in transplant recipients were investigated. 3D-STE yielded lower magnitude of global LSt compared with 2D-STE (-13 ± 3 vs. -16 ± 3%, P < 0.001). The inferolateral wall was a source of variation between 3D- and 2D-STE both for LSt and CSt. Inferolateral wall 3D-STE-derived RDisp was greater than that observed in control subjects (7.4 ± 1.2 vs. 6.5 ± 1.7 mm, P = 0.03), while anteroseptal RDisp was lower than controls (4.2 ± 1.0 vs. 7.3 ± 1.6 mm, P < 0.001). Multiple regression analysis demonstrated that 3D-STE-derived LSt was independently associated with NYHA class (P < 0.001), while 2D-STE-derived LSt was not. CONCLUSION: Examination of LV mechanics by 3D- and 2D-STE deformation parameters in heart transplant recipients yields significantly discordant results. 3D-STE-derived LSt is independently associated with NYHA class, suggesting a clinically important relationship between functional status and myocardial mechanics.