[NT-proBNP in elderly inpatients: an useful marker for detecting heart failure?]. / NT-proBNP nei pazienti anziani: un valido marcatore per la diagnosi di scompenso cardiaco?

In this study we try to determine a cut off for detecting heart failure (HF) with the highest sensitivity and specificity in a population of hospitalized people aged > or = 65 years and to identify potential confounding variables for the interpretation of plasma concentration of the marker. We evaluated 212 consecutive patients admitted to our Department of Medicine, the only inclusion criterion being an age > or = 65 years. We identified a group with clinical and/or instrumental HF, and among remaining patients we selected a normal group without obvious cardiac disease. The strongest predictors of higher levels of NT-proBNP resulted age and free-triiodothyronine as in all models they were strongly associated with Log NT-proBNP. Using receiver-operating characteristics (ROC) curves, we found an optimal discriminatory value for detecting HF in 879 pg/ml for subjects aged between 65 and 74 years and 1658 pg/ml for subjects aged > or = 75 years. In elderly hospitalized patients the discriminatory cut offs of NT-proBNP for the diagnosis of HF are significantly higher than community derived reference values. Adjustments for the independent effects of age and other confounding variables appear necessary.

Early detection of cardiac dysfunction in patients with anorexia nervosa by tissue Doppler imaging.

BACKGROUND: Cardiac damage is a major complication of chronic starvation. The aim of this study was to evaluate the changes of left ventricular function in patients with anorexia nervosa by means of pulsed tissue Doppler imaging. METHODS: A total of 20 females (age 22.4+/-4.3 years) with overt anorexia nervosa, 20 matched healthy thin females with body mass index < 19 kg/m2 and 20 matched healthy normal-weight females underwent both standard echocardiography and tissue Doppler imaging. Myocardial systolic wave (Sm) and early (Em) and atrial (Am) diastolic waves were measured on the basal lateral segment and the basal interventricular septum from the apical four-chamber view. RESULTS: When compared with control groups, the anorexia nervosa group showed lower left ventricular mass (p < 0.0001), lower Sm peak of both lateral wall (6.5+/-0.9 vs. 9.4+/-2.1 and vs. 9.5+/-1.9 cm/sec, p < 0.001) and septum (5.6+/-1.5 vs. 8.6+/-1.6 and vs. 8.8+/-1.5 cm/sec, p < 0.001), and comparable Em, Am and Em/Am ratio. The ratio between transmitral peak E and Em was significantly greater in anorexic patients than in controls (lateral wall: 8.1+/-0.1 vs. 6.8+/-0.2 and vs. 6.9+/-0.2, p < 0.001; septum: 10.8+/-0.4 vs. 8.8+/-0.5 and vs. 8.8+/-0.3, p < 0.001). No differences were observed between thin and normal-weight females. In the anorexia nervosa group, S(m) peak was significantly related to left ventricular mass indexed, at both septum (r = 0.55, p < 0.02) and lateral wall (r = 0.49, p < 0.03) levels. CONCLUSIONS: These results show that anorexia nervosa is associated with left ventricular systolic dysfunction, which is related with the reduction of cardiac mass. Tissue Doppler imaging can give useful information in the identification of regional left ventricular dysfunction, in addition to traditional parameters.

Skin vasoreactivity to insulin iontophoresis is reduced in elderly subjects and is absent in treated non-insulin-dependent diabetes patients.

We investigated the skin vasoreactivity to insulin in normal subjects and in treated non-insulin-dependent diabetes mellitus (NIDDM) patients. We measured cutaneous perfusion by laser-Doppler flowmetry (LDF) at rest and during skin cathodal iontophoresis (six pulses of 0.1 mA each for 20 s, with 40 s interval between stimulations) of insulin (0.1 ml Humulin R 100 IU/ml diluted 1/10 with of 0.9% saline solution) in 45 healthy subjects (HS), (25 males, 20 females, aged 45 +/- 18 years), and in 15 treated NIDDM patients (13 males), aged 66 +/- 8 years. Fifteen of the HS were used as controls. In these 15 sex- and age-matched HS and in the patients, we assessed also the skin postischemic hyperemia by LDF. In HS cutaneous blood flux response (CBF) to iontophoresis of insulin in saline (expressed as percent changes from baseline) was significantly higher than CBF response to iontophoresis of pure saline (maximum response: 360 +/- 51% versus 172 +/- 42%, respectively; P < 0.001, ANOVA for repeated measures). The maximum "net" CBF response to insulin (response to insulin minus response to saline) showed a negative correlation (r = -0.361; P < 0.01) with age in HS, and resulted significantly lower in the oldest than in the youngest HS (105 +/- 40% versus 307 +/- 45%, respectively; P < 0.01). No significant correlation was observed between the maximum CBF response to saline and the age of subjects. In NIDDM patients the "net" CBF response to insulin iontophoresis resulted significantly lower than in 15 sex- and age-matched control subjects (maximum response: -50 +/- 89% versus 201 +/- 81%, respectively; P < 0.001, ANOVA for repeated measures). No significant difference was observed between diabetics and controls, nor in basal perfusion (6.5 +/- 1.3 IU versus 6.8 +/- 1.7 IU, respectively) neither in the skin postischemic hyperemia (250 +/-14% versus 258 +/- 27%, respectively). These results confirm that insulin iontophoresis induces a skin vasodilatatory effect in normal subjects and show that this effect is reduced by aging and is absent in treated NIDDM patients. The local skin vasodilatatory effect induced by insulin seems to involve mechanisms different from those underlying the skin postischemic hyperemia.

Heart rate variability and left ventricular diastolic function in anorexia nervosa.

PURPOSE: To investigate the cardiac effects of starvation in a group of adolescents with anorexia nervosa (AN). METHODS: Twenty-five patients with AN (range 13-20 years), compared with 25 age-matched thin and 25 age-matched control women with body mass index > 20 Kg/m(2), underwent a complete clinical evaluation, including echocardiogram and 24-hour electrocardiogram monitoring to evaluate heart rate variability (HRV) indices. RESULTS: Compared to both thin and control women, patients with AN had greater HRV time domain indices (SDNN: 246.5 +/- 32.4 vs. 170.4 +/- 24 ms and vs. 181 +/- 21.2 ms, p <.001), and in the frequency domain a lower LF/HF ratio (4.2 +/- 1.3 vs. 6.7 +/- 1.2 and vs. 6.8 +/- 1.3 ms, p <.001). AN patients showed reduced left ventricular mass with normal systolic function and typical diastolic patterns, characterized by a lower peak velocity transmitral flow in late diastole (peak A: 35.9 +/- 8.5 vs. 45.2 +/- 7.3 cm/sec and vs. 46.6 +/- 6.3 cm/sec, p <.01), a comparable peak velocity in early diastole (peak E: 92.7 +/- 12.1 vs. 83 +/- 6.2 and vs. 86.8 +/- 9.1 cm/sec, ns) and, subsequently, a greater E/A ratio (2.8 +/- 0.7 vs. 1.8 +/- 0.3 and vs. 1.9 +/- .5, p <.01) than thinness and control groups. Moreover, SDNN was also positively related to E/A ratio (r =.54, p <.01). CONCLUSIONS: Our findings demonstrate a cardiovascular vagal hyperactivity in AN, which appears to influence the ventricular diastolic dynamics. HRV and diastolic function analysis may represent useful tools in monitoring anorexia-induced cardiac modifications.

Endothelium-dependent and endothelium-independent skin vasoreactivity in the elderly.

BACKGROUND AND AIMS: It was demonstrated that endothelium-dependent vasoreactivity, an aspect of endothelial functioning, is impaired in coronary and brachial arteries, and in skeletal muscle resistance vessels of elderly people. However, little data is available about the influence of aging per se on the endothelial function of the skin microcirculation. The aim of the present study was to evaluate the endothelial function and intrinsic vasodilatory capacity of the skin microcirculation in elderly people with a low atherosclerosis risk profile. METHODS: Using laser Doppler flowmetry, we measured the cutaneous hyperemic responses following local iontophoresis delivery of an endothelium-dependent vasodilator, acetylcholine (ACh), and an endothelium-independent vasodilator, sodium nitroprusside (SNP), in 15 subjects older than 65 years and in 15 subjects younger than 50 years. Exclusion criteria were diabetes, hyperlipidemia, smoking, arterial hypertension and cardiovascular diseases. RESULTS: Skin maximal hyperemic responses induced both by ACh and by SNP delivery did not differ between the younger and the older groups. Cutaneous blood flow progressively increased in response to the 8 ACh delivery steps, both in the older and younger groups; however, the dose-response curve following ACh delivery was significantly lower in the former (p < 0.001). CONCLUSIONS: While these results should be viewed as preliminary due to the small sample size, they suggest that aging in itself is associated with a mild endothelium dysfunction in the skin microcirculation, whereas its overall vasodilatory capacity is preserved.