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Background. Exercise intolerance is the primary chronic symptom in patients with heart failure and preserved ejection fraction (HFPEF), the most common form of heart failure in older persons, and can result from abnormalities in cardiac, vascular, and skeletal muscle, which can be further worsened by physical deconditioning. However, it is unknown whether skeletal muscle abnormalities contribute to exercise intolerance in HFPEF patients. Methods. This study evaluated lean body mass, peak exercise oxygen consumption (VO2), and the short physical performance battery in 60 older (69±7 years) HFPEF patients and 40 age-matched healthy controls. Results. In HFPEF versus healthy controls, peak percent total lean mass (60.1±0.8% vs. 66.6±1.0%, p < .0001) and leg lean mass (57.9±0.9% vs. 63.7±1.1%, p = .0001) were significantly reduced. Peak VO2 was severely reduced including when indexed to leg lean mass (79.3±18.5 vs. 104.3±20.4ml/kg/min, p < .0001). Peak VO2 was correlated with percent total (r = .51) and leg lean mass (.52, both p < .0001). The slope of the relationship of peak VO2 with percent leg lean mass was markedly reduced in HFPEF (11±5ml/min) versus healthy controls (36±5ml/min; p < .001). Short physical performance battery was reduced (9.9±1.4 vs. 11.3±0.8) and correlated with peak VO2 and total and leg lean mass (all p < .001). Conclusion. Older HFPEF patients have significantly reduced percent total and leg lean mass and physical functional performance compared with healthy controls. The markedly decreased peak VO2 indexed to lean body mass in HFPEF versus healthy controls suggests that abnormalities in skeletal muscle perfusion and/or metabolism contribute to the severe exercise intolerance in older HFPEF patients. [ABSTRACT FROM PUBLISHER]

The cardiovascular and thermoregulatory systems are considered to be susceptible in the aged population, but little is known about baseline cardiac and thermoregulatory homeostasis in rodent models of aging. Radiotransmitters were implanted in male, Brown Norway rats obtained at 4, 12, and 24 months to monitor the electrocardiogram (ECG), interbeat interval (IBI), heart rate (HR), core temperature (Tc), and motor activity (MA). There was no significant effect of age on resting HR and MA. Daytime Tc of the 24-month-old rats was significantly elevated above those of the 4- and 12-month-old groups. Variability of the IBI was highest in the 24-month-old rats. The elevation in daytime Tc beginning around 8 months of age may be a physiological biomarker of aging and may be an important factor to consider in studies using caloric restriction-induced hypothermia to increase longevity. [ABSTRACT FROM AUTHOR]

Discusses age-related changes in cardiovascular responses to catecholamines. Age-related differences in contractile responses to dopamine; Increase atrioventricular-atrioventricular interval and atrioventricular conduction in senescent hearts; Differences in responses to myocardial catecholamine release.

Reports on the prevalence of intermittent claudication (IC) in ambulatory community-resident adults age 65 years or older. Comparison of cardiovascular risk factors and comorbidity of persons with and without IC; Examination of the independent association of IC in predicting all cause and cardiovascular mortality, myocardial infarction, stroke and disability.