Suchergebnisse

Background-Experimental studies have demonstrated that lead and cadmium have direct toxic effects on the myocardium, but the few human studies are limited by design, assessment of exposure, and use of heart failure as a late-stage endpoint. Methods and Results-In a prospective population study, we studied the association of left ventricular (LV) function with blood lead (BPb) and 24-hour urinary cadmium (UCd). In 179 participants randomly recruited from a Flemish population (50.3% women; mean age 39.1 years), geometric mean BPb and UCd at enrollment (1985-2000) were 0.20 mu mol/L and 6.1 nmol, respectively. We assessed systolic and diastolic LV function 11.9 years (median) later (2005-2010) by using Doppler imaging of the transmitral blood flow and the mitral annular movement and speckle tracking. In multivariable-adjusted linear regression, LV systolic function decreased with BPb. For a doubling of exposure, estimates were -0.392% for global longitudinal strain (P=0.034), -0.618% and -0.113 s (1) for regional longitudinal strain (P=0.028)and strain rate (P=0.008), and -0.056 s (1) for regional radial strain rate (P=0.050). Regional longitudinal strain rate (-0.066 s (1), P=0.009)and regional radial strain (-2.848%, P=0.015) also decreased with UCd. Models including both exposure indexes did not allow differentiating whether LV dysfunction was predominately related to BPb or UCd. Diastolic LV function was not associated with BPb or UCd (P=0.159). Conclusions-Although effect sizes were small, our results suggest that environmental exposure to lead, cadmium, or both might be a risk factor for systolic LV dysfunction, a condition often proceeding to heart failure. ; European Union [HEALTH-FP7-278249-EUMAS-CARA, HEALTH-F7-305507 HOMAGE]; European Union (European Research Council) [2011-294713-EPLORE]; European Union (Proof-of-Concept Grant) [713601-uPRO-PHET]; Fonds voor Wetenschappelijk Onderzoek Vlaanderen, Ministry of the Flemish Community, Brussels, Belgium [G.0881.13, G.0880.13]

Background-The metabolic signature associated with subclinical diastolic left ventricular (LV) dysfunction in the population remains ill defined. Methods and Results-In 711 randomly recruited Flemish (50.8% women; mean age, 50.8 years), we assessed echocardiographic Doppler indexes of diastolic LV function in relation to 44 circulating metabolites determined by nuclear magnetic resonance spectroscopy. In multivariable-adjusted regression analysis with Bonferroni correction of significance levels applied, peak a' decreased (P <= 0.048) and e'/a' increased (P <= 0.044) with circulating tyrosine, high-density lipoprotein apolipoproteins, glucose+glutamine, and an unidentified molecule. Effect sizes expressed per 1-SD increment in the metabolite ranged from -0.277 to -0.203 cm/s for peak a' and from +0.047 to +0.054 for e'/a'. In addition, peak a' decreased (P <= 0.031) with glucose+2-aminobutyrate (-0.261 cm/s) and glucose+2-phosphoglycerate (-0.209 cm/s). In partial least square discriminant analysis (PLS-DA), metabolites associated with normal diastolic LV function (n=538) included glucose+glutamine, glucose+2-aminobutyrate, and glucose+2-phosphoglycerate, whereas those siding with abnormal function encompassed 4-aminobutyrate, 4-hydroxybutyrate, creatinine, and phosphocholine. In receiver operating characteristics plots, adding 3 latent factors identified by PLS-DA to prohormone brain natriuretic peptide increased (P<0.0001) the area under the curve from 0.64 (95% CI, 0.58-0.68) to 0.73 (0.68-0.78). Conclusions-In a general population, circulating metabolites indicative of energy substrate utilization and protection against oxidative stress differentiated normal from abnormal diastolic LV function. These findings improve our understanding of the pathophysiology underlying deterioration of diastolic LV function and potentially point to new targets for prevention and treatment of this condition. ; The European Union (grants HEALTH-2011.2.4.2-2-EU-MASCARA, HEALTH-F7-305507 HOMAGE, and the European Research Council Advanced Researcher Grant-2011-294713-EPLORE) gave support to the Studies Coordinating Centre (Leuven, Belgium). The Fonds voor Wetenschappelijk Onderzoek Vlaanderen, Ministry of the Flemish Community (Brussels, Belgium; G.0881.13, G.0880.13, and 11Z0916N) also supported the FLEMENGHO study.

BACKGROUND The association of electrocardiographic left ventricular hypertrophy (ECG-LVH) with blood pressure (BP) in Blacks living in sub-Saharan Africa remains poorly documented. METHODS In 225 Black Nigerians and 729 White Flemish, we analyzed QRS voltages and voltage-duration products and 12 criteria diagnostic of ECG-LVH in relation to office BP (mean of 5 consecutive readings) and home BP (duplicate morning and evening readings averaged over 1 week). RESULTS In multivariable analyses, QRS voltage and voltage-duration indexes were generally higher in Blacks than Whites. By using any of 12 criteria, ECG-LVH was more prevalent among Black than White men (54.4% vs. 36.0%) with no ethnic difference among women (17.1%). Precordial voltages and voltage-duration products increased with office and home systolic BP (SBP), and increases were up to 3-fold steeper in Blacks. In Blacks vs. Whites, increases in the Sokolow-Lyon voltage associated with a 10-mm Hg higher SBP were 0.18 mV (95% confidence interval [CI], 0.09-0.26) vs. 0.06 mV (0.02-0.09) and 0.17 mV (0.07-0.28) vs. 0.11 mV (CI, 0.07-0.15) for office and home BP, respectively, with a significant ethnic gradient (P < 0.05). The risk of ECG-LVH increased more with office and home BP in Blacks than Whites. CONCLUSIONS Associations of ECG voltages and voltage-duration products and risk of ECG-LVH with BP are steeper in Black Nigerians compared with a White reference population. In resource-poor settings of sub-Saharan Africa, the ECG in combination with office and home BP is an essential instrument in risk stratification across the entire BP range. ; The authors gratefully acknowledge the expert clerical assistance of Mrs. Vera De Leebeeck and Mrs. Renilde Wolfs (Studies Coordinating Centre, Leuven, Belgium). The European Union (HEALTH-FP7-278249-EUMASCARA, HEALTH-F7-305507 HOMAGE and the European Research Council (Advanced Researcher Grant 2011-294713-EPLORE and Proof-of-Concept Grant 713601-uPROPHET) and the Fonds voor Wetenschappelijk Onderzoek Vlaanderen, Ministry of the Flemish Community, Brussels, Belgium (G.0881.13, G.088013, and 11Z0916N) currently support the Studies Coordinating Centre in Leuven.