Metabolic syndrome shown to enhance sympathetic activation in congestive heart failure

Congestive heart failure (CHF) is characterized by an exceedingly high adrenergic drive, which may be aggravated when CHF is complicated by a concomitant metabolic syndrome, a phenotype often associated with heightened adrenergic drive. In 48 age-matched control subjects and 89 CHF patients (NYHA class II), among whom 47 without metabolic syndrome and 42 with metabolic syndrome, waist circumference, blood pressure, and metabolic variables were greater in CHF patients with metabolic syndrome than in those without metabolic syndrome whereas left ventricular ejection fraction and end-diastolic diameter were similarly altered in the two CHF groups. Sympathetic nerve activity was higher in CHF patients without metabolic syndrome (P<0.01), and even further increased in those with metabolic syndrome (P<0.01), as compared to controls. Baroreflex responses were significantly impaired in the 2 CHF groups compared to controls, the impairment being more pronounced in patients with than in those without the metabolic syndrome. The potentiating effect of obesity and metabolic syndrome on sympathetic activation in heart failure could depend on metabolic (including adipokines) and/or baroreflex mechanisms.

Abstract