Search

Simultaneous with a 12 channel ECG, body composition was analysed by segmental multi-frequency impedance analysis in 101 healthy subjects and in 118 patients with chronic heart failure (CHF, n= 40), chronic renal failure with haemodialysis (HD, n= 20), and miscellaneous internal diseases (n= 58). Whole body DXA and sodium bromide dilution were used as reference methods for total body water (TBW), extracellular fluid (ECF), appendicular muscle mass (AppMM) and fat mass (FM). Empirical prediction equations were developed in a randomized evaluation sample and then evaluated in unknowns. TBW, ECF, AppMM and FM could be predicted with regression coefficients of 0.96, 0.90, 0.95 and 0.93, respectively, all with p< 0.001. Only segmental impedances and height, but not age, sex, weight and BMI contributed to the prediction of water compartments. About half the patients with CHF and half of those on HD showed increased ECF/ICF ratio in relation to % FM at the legs but not at the thorax. The predicted AppMM was additionally corrected for increased ECF to determine "dry AppMM", which is markedly lower than the misleading reference DXA. This methodology shows promise as a combination of routine ECG with measurement of body composition, assessment of sarcopenia and detection of overhydration., (Copyright © 2017 IPEM. Published by Elsevier Ltd. All rights reserved.)

Orthostatic hypotension in patients with cobalamin (Cbl) deficiency has been reported previously in isolated cases but we are not aware of detailed systematic studies of hemodynamic and autonomic nervous system function in patients with cobalamin deficiency. We investigated hemodynamic and autonomic responses to 60 degrees passive head up tilt (HUT) in 21 patients with vitamin B12 deficiency, 21 healthy age-matched control subjects and 9 age-matched patients with diabetes mellitus (DM) and established diabetic neuropathy. To systematically assess hemodynamic and autonomic nervous system function, we performed measurements of heart rate, beat-to-beat systolic and diastolic blood pressure, stroke index, cardiac index, total peripheral resistance index, total power, low (LF) and high (HF) frequency oscillatory component of heart rate variability, LF/HF ratio and spontaneous baroreflex sensitivity. As compared to controls, we found a significant fall of systolic blood pressure during 60 consecutive beats directly after head up tilt; furthermore, a significantly blunted fall of stroke index, cardiac index and a lack of increase of total peripheral resistance index for the duration of tilt in patients with diabetes mellitus and in patients with vitamin B12 deficiency. As compared to controls, we observed an altered response of spectral indices of sympathetic activation and vagal withdrawal and an impaired modulation of baroreflex sensitivity during head up tilt suggestive of a complex modification in the neural control activities in patients with cobalamin deficiency, which was comparable to that observed in patients with diabetes mellitus and established autonomic neuropathy. The results suggest that vitamin B12 deficiency causes autonomic dysfunction with similar hemodynamic consequences and patterns of autonomic failure as seen in diabetic autonomic neuropathy. Defective sympathetic activation may be the cause for orthostatic hypotension, which is occasionally seen in patients with vitamin B12 deficiency. It is concluded that patients with orthostatic hypotension should be screened for cobalamin deficiency.

Abstract: Objectives: In primary care the diagnosis of CHF and ECF accumulation is no triviality. We aimed to predict plasma BNP, CHF and ECF accumulation with segmental impedance spectroscopy while using and extending the electrodes of the conventional electrocardiography. Methods: Three combined multiple electrodes were added to the 15 lead ECG for segmental impedance spectroscopy and for measuring the maximal rate of segmental fluid volume change with heart action at the thorax and the legs. The obtained signals were analyzed by partial correlation analyses in comparison with plasma BNP, CHF classes, ejection fraction by echocardiography and cardiac index by double gas re-breathing. 119 subjects (34 healthy volunteers, 50 patients with CHF, NYHA classes II to IV and 35 patients without CHF) were investigated. Results: The maximal rate of volume change with heart action at the thorax and at the legs, as well as the ECF/ICF ratio at the legs contribute equally and independently to the prediction of BNP and heart failure in an unknown test sample of 49 patients (multiple r =0.88, p <0.001). The ROC-curve for the predicted plasma BNP>400pg/ml gave an AUC=0.93. The absence or the presence of heart failure could be predicted correctly by a binomial logistic regression in 92.9 and 87.5% of cases, respectively. Conclusion: The methodology, which is based on inverse coupling of BNP release and of maximal blood acceleration and on sensitive detection of ECF overload, could enable the diagnosis of CHF with useful sensitivity and specificity while writing a routine-ECG. [Copyright &y& Elsevier]

We hypothesized that the extreme endurance exercise of an Ironman competition would lead to long-standing hemodynamic and autonomic changes. We investigated also the possibility of predicting competition performance from baseline hemodynamic and autonomic parameters. We have investigated 27 male athletes before competition, 1 h after, and then for the following week after the competition. The Task Force monitor was used to measure beat-to-beat hemodynamic and autonomic parameters during supine rest and active standing. Heart rate (P < 0.001) was increased, and stroke index (P = 0.011), systolic blood pressure (P = 0.004), diastolic blood pressure (P < 0.001), total peripheral resistance index (P < 0.001), and baroreceptor reflex sensitivity (P < 0.001) were decreased after the competition. The 0.05- to 0.17-Hz band of heart rate and blood pressure variability was increased (P < 0.001 and P < 0.001, respectively), the 0.17- to 0.40-Hz band of heart rate interval variability was decreased after the competition (P < 0.001). All parameters returned to baseline values 3 days after the competition. After the competition, the autonomic response to orthostasis was significantly impaired. The 0.05- to 0.17-Hz band of diastolic blood pressure variability before competition and weekly net exercise training, but not the other hemodynamic and autonomic parameters, were related to competition time in multivariate regression analysis (multiple r = 0.70, P < 0.001). The marked hemodynamic and autonomic changes after an ultraendurance race, which are compatible with myocardial depression in the face of sympathetic activation and reduction of afterload, return to baseline after only 1-3 days. Because the 0.05- to 0.17-Hz band of diastolic blood pressure variability contributes to the prediction of competition time, the analysis of blood pressure variability in the frequency domain deserves further study for the prediction of endurance capacity. [ABSTRACT FROM AUTHOR]