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G Rudofsky

Publications and source records attributed to G Rudofsky.

135 records · Page 8Linked to original sources
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Venous pressure dynamics of the healthy human leg. Role of muscle activity, joint mobility and anthropometric factors.

The delicate interplay between the muscle-joint unit and intact venous valves is mandatory for normal venous blood return from the human leg. We have investigated the potential role of (1) muscle activity and joint mobility, and (2) anthropometric factors for peripheral venous pressure physiology. 20 healthy young subjects (10 males, 10 females; mean age: 25.6 +/- 3.1 years) underwent direct venous blood pressure measurements during walking on a treadmill in 12 experimental conditions (duration, 1 min each): these resulted from a combination of two different walking velocities, two different degrees of ascent, and three different walking conditions. Anthropometric parameters (e.g., body height, weight and calf circumference) were also measured in all subjects. Outcome measures were the pressures (mm Hg) during quiet standing (resting pressure, P(0)), the maximal activity-induced pressure reduction (Delta P(max)), i.e., the difference between the resting pressure (P(0)) and minimal pressure during exercise (P(min)), the times (s) to minimal pressure during exercise (T(Pmin)) and to half-maximal recovery of P(0) after exercise (T(max1/2)). We found that the maximal venous pressure reduction (Delta P(max)) during walking increased at the higher walking speed and decreased with restricted joint mobility (p = 0.0001). Taller and heavier subjects, or subjects with a greater calf circumference had higher P(0) (p = 0.0001), showed greater Delta P(max) (p < 0.010), and took longer to achieve minimal pressure during exercise (T(Pmin); p < 0.010) than their corresponding counterparts. Females had lower levels of P(0) (p = 0.0001), but not of Delta P(max), and shorter T(Pmin) (p = 0.0076) than males. These gender effects largely result from differences in body height, weight, and calf circumference (p = 0.0001 for the appropriate ANOVA interaction terms). We conclude that during walking, a higher degree of muscle activity and a greater muscle mass enhance venous emptying of the healthy human leg. Conversely, impairments of joint mobility reduce the efficacy of the muscle-vein pump. Moreover, body height and weight significantly influence venous pressure physiology under both resting and activity-related conditions. These anthropometric factors also largely explain sex differences in peripheral venous hemodynamics.

Adult↗
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Patient age and patency rate after recanalization of occluded peripheral arteries.

OBJECTIVES: Due to an increase in the percentage of older people in industrialized countries there is an increasing demand for medical care for the elderly. With advancing age, a series of structural, architectural and compositional modifications take place in the vasculature. Therefore, we analyzed the influence of patient age on the reocclusion rate of recanalized peripheral arteries. PATIENTS AND METHODS: 471 patients (mean age +/- SD: 62 +/- 12 years, range: 28-90 years) successfully treated by interventional recanalization were followed up (mean +/- SD: 18 +/- 17 months, range:6-48 months). Reocclusion of the recanalized arterial segment could be proven in 175 patients (37%), whereas octogenarians had the highest patency rate i.e. 68%. Univariate analysis, multivariate logistic regression analysis, and ROC analysis were performed. RESULTS: The univariate analysis showed a significant relation between reocclusion and PAOD stage, hyperlipoproteinemia, and total cholesterol level and erythrocyte sedimentation rate (ESR), respectively. Excluding age-related risk factors, the multivariate logistic regression analysis with backward selection reached a significant level for PAOD stage with p = 0.0012 and an odds ratio of 1.63, and for ESR with a p = 0.0013 and an odds ratio of only 1.02. Age did not reach a significant level with a p value of 0.13 and an odds ratio of 0.98. In the ROC analysis, prognostic relevance could be shown for the combination of PAOD stage and ESR adjusted for age and hyperlipidemia, and for PAOD stage and ESR value as a single prognostic factor, but not for patient age. CONCLUSION: Thus, despite proven and hypothetical differences in the vascular biology of older people compared to younger people, age is not related to middle term patency rates after interventional recanalization of peripheral arterial occlusions.

Adult↗