Renal artery stenosis predicts adverse cardiovascular and renal outcome in patients with peripheral artery disease.

BACKGROUND: Patients with symptomatic peripheral artery disease (PAD) are considered cardiovascular high-risk patients. Our aim was to investigate whether incidental renal artery stenosis (RAS) increases the risk for adverse cardiovascular and renal outcomes in these patients. MATERIALS AND METHODS: We prospectively enrolled 487 consecutive patients admitted for revascularization of symptomatic PAD and performed a renal overview angiogram categorizing RAS as absent (0-29%), moderate (30-59%) and severe (>or= 60%) respectively. Clinical follow-up was for median 15 months (IQR 12-22) for the occurrence of major adverse events [MAE: composite of death, myocardial infarction (MI), stroke, percutaneous coronary intervention, coronary bypass surgery, amputation and kidney failure]. Glomerular filtration rates (GFR) were obtained at 12 months to quantify the course of renal function. RESULTS: A severe RAS was found in 76 patients (15.6%). Overall MAE occurred in 121 patients (24.8%), the composite endpoint of MI, stroke, amputation and death occurred in 101 patients (20.7%). Patients with a severe RAS had a 1.87-fold increased adjusted risk for MAE (95% CI 1.12-3.12, P = 0.017), a 2.51-fold increased adjusted risk for occurrence of the composite endpoint of MI, stroke, amputation and death (95% CI 1.45-4.34, P = 0.001) and a 2.93-fold increased risk for death (95% CI 1.41-6.08, P = 0.004), compared to those of patients without RAS respectively. We observed a significant association between the decrease of GFR over the 12-month follow-up period and the severity of RAS by multivariable analysis (P = 0.044). CONCLUSION: Severe RAS in patients with symptomatic PAD is an independent predictor of major adverse cardiovascular events, adverse renal outcome and mortality.

Influence and interaction of diabetes and lipoprotein (a) serum levels on mortality of patients with peripheral artery disease.

BACKGROUND: Diabetes mellitus is a risk factor for early complications and mortality in patients with peripheral artery disease. Lipoprotein (a) [Lp(a)] is also suggested to be a marker of increased cardiovascular risk. We investigated the association and interaction between diabetes mellitus, lipoprotein(a) and mortality in high risk patients with peripheral artery disease (PAD). METHODS: We studied 700 consecutive patients [median age 73 years, interquartile range (IQR) 62-80, 393 male (56%)] with PAD from a registry database. Atherothrombotic risk factors (diabetes, smoking, hyperlipidaemia, arterial hypertension) and Lp(a) serum levels were recorded. We used stratified multivariate Cox proportional hazard analyses to assess the mortality risk at a given patient's age with respect to the presence of diabetes and Lp(a) serum levels (in tertiles). RESULTS: Patients with Lp(a) levels above 36 mg dL(-1) (highest tertile) and insulin-dependent type II diabetes had a 3.01-fold increased adjusted risk for death (95% confidence interval 1.28-6.64, P = 0.011) compared to patients without diabetes or patients with non-insulin-dependent type II diabetes. In patients with Lp(a) serum levels below 36 mg dL(-1) (lower and middle tertile), diabetes mellitus was not associated with an increased risk for death. CONCLUSION: Insulin-dependent type II diabetes mellitus seems to be associated with an increased risk for mortality in PAD patients with Lp(a) serum levels above 36 mg dL(-1). PAD patients with non-insulin-dependent type II diabetes, and patients with diabetes and Lp(a) levels below 36 mg dL(-1) showed survival rates comparable to PAD patients without diabetes.

Long-term follow-up after percutaneous transluminal angioplasty of the distal abdominal aorta.

Aortoiliac disease can be either treated with surgery-endarterectomy for localized aortic disease or with bypass graft placement for more extensive aortoiliac disease--or with percutaneous transluminal angioplasty (PTA), which has become an established method. Long term results of surgery are well documented in literature, but long term results of distal aortic PTA are scarce, furthermore angiographic follow-up is very uncommon. We report about a patient with isolated aorta abdominalis stenosis due to atherosclerotic disease who underwent PTA in 1982 and had an angiographic follow-up four and twenty years later, thus we demonstrate that patency can be obtained even after twenty years.

Reduction in renal function after renal arteriography and after renal artery angioplasty.

OBJECTIVE: To investigate the incidence and risk factors for renal function deterioration after renal angiography and angioplasty or stenting. METHODS: A retrospective study of 85 consecutive patients undergoing selective renal artery arteriography (n = 53) or renal artery angioplasty % (PTRA) stenting (n = 32) for renal artery stenosis. Multivariate logistic regression analysis was used to determine independent predictors of deterioration of renal function, defined as an increase of serum creatinine by at least one third within 24 h. RESULTS: Deterioration of renal function occurred in 13 patients (15%), [8/53 (15%) after angiography and 5/32 (16%) after PTRA/stenting]. Only pre-existing renal impairment (se-creatinine > or = 177 mumol/l) (Odds ratio: 40; 95% confidence interval 1.2-72, p = 0.02) and administered dosage of contrast agent (more than 225 ml) (OR 67; 95% CI 11.8-100, p = 0.02) were independently associated with renal function deterioration. CONCLUSION: Transient renal dysfunction after renal artery angiography or PTRA/stenting occurs in about 15% of patients, but persistent renal failure is uncommon. Pre-existing renal impairment and amount of contrast agent are independent risk factors. Endovascular treatment of renal artery stenosis is not associated with a higher risk of renal deterioration compared to selective renal angiography.

Clinical outcome and prognostic factors for ischaemic ulcers treated with PTA in lower limbs.

OBJECTIVE: To analyse the clinical outcome of patients with ischaemic ulcers (Fontaine stage IV) undergoing percutaneous transluminal angioplasty (PTA). METHODS AND DESIGN: Retrospective cohort study of 40 patients (21 males) treated between January 1998 and December 1998. Cardiovascular risk factors, co-morbid, baseline laboratory, angiographic data and technical success were recorded. Patients were followed for a median of 20 (inter quartile range (IQR) 8-26) months. RESULTS: Cumulative ulcer healing rates at 3, 6, 12, and 24 months were 15, 40, 54 and 81%, respectively. The median time to healing was 5 (IQR 2-7) months. Cumulative restenosis at 1, 3, 6 and 12 months was 3, 10, 29 and 52%, respectively. Nine patients (22%) suffered ulcer reappearance. Lipoprotein (a) serum levels > 30 mg/dl (HR 0.2, 95% CI 0.05-1.0, p = 0.05) and diabetes mellitus (HR 0.2, 95% CI 0.5-0.7, p = 0.01) were associated with delayed ulcer healing. CONCLUSION: PTA leads to ulcer healing in the majority of patients. Elevated lipoprotein (a) levels > 30 mg/dl and diabetes mellitus are independently associated with ulcer persistence.

The life-shortening effect of reduced physical activity is abolished by a fat rich diet.

In female mice on a control diet (3.6% fat) reduced physical activity leads to a reduction of the average life span. So the average age at death of an inactive group is 500 +/- 166 compared to 565 +/- 175 days in an active control group. If the animals are kept on a fat rich diet (12.4% fat) this effect of physical activity restriction is no longer observable and the average age at death is 570 +/- 142 days, within the range of the control animals. The increased fat intake seems to reduce the stress or to increase the resistance to stress in the activity restricted animals. So stress is a crucial determinant of life span.

The effect of reduced physical activity on longevity of mice.

Reduced physical activity leads, in female mice, to a reduction of the average and maximal life span. The average age at death of the inactive experimental group was 497 +/- 121 days (mean +/- S.D.) compared to 557 +/- 139 days in the active control group, and the six oldest inactive experimental mice died at age 732 +/- 50 days, while the six oldest active control mice died at 890 +/- 52 days. The restriction of mobility was connected with a higher growth rate and a higher body weight in spite of a significant decrease in food intake. In spite of a reduced food intake leading to a reduced whole body metabolism, the results show that mobility restriction shortens life span in female mice.

Effect of chronic alcohol consumption on rat brain microsome lipid composition, membrane fluidity and Na+-K+-ATPase activity.

The present study reports differences in phospholipid classes, fatty acids of individual phospholipids, and changes in membrane fluidity and Na+-K+-ATPase activity in brain microsomes of rats maintained on an alcohol diet for 35 days compared to sex, age and weight-matched control rats maintained on a calorically-equivalent, non-alcohol diet. Although no difference in Na+-K+-ATPase activity was found in microsomes from alcohol vs control rats when measured in the absence of added alcohol, the presence of low concentrations of ethanol (less than 100 mM) stimulated, while high concentrations (greater than 100 mM) inhibited enzyme activity. The stimulation was differentially expressed in that the microsomal enzyme from alcohol rats was stimulated to a lesser extent than the enzyme from control rats. However, the inhibiting effect of high concentrations of alcohol was similar in microsomes from both alcohol and control rats. Also in membranes from alcohol rats, there was a lower quantity of phosphatidylethanolamine (PE) and higher quantities of phosphatidylserine (PS) and phosphatidylinositol (PI) compared to membranes from control rats. The major change in fatty acid composition was a reduction in the level of polyunsaturated fatty acids, which was particularly evident in PI and PS. The linoleic acid: arachidonic acid ratio (18:2/20:4) and the saturation:unsaturation ratio were also increased in PI and PS in membranes from alcohol animals. However, the ratio of n-6/n-3 fatty acids remained the same or was reduced in membranes from alcoholic animals. Although no difference in the inherent "fluidity" of membranes from alcohol vs control rats could be demonstrated by electron paramagnetic resonance, molecular tolerance to ethanol was demonstrated in the membranes from alcohol rats by the resistance to the disordering effects of added ethanol.

Studies of the behaviour of isolated cells in an open system.

A computer-aided arrangement was used to study the time function of lactate output of isolated intestinal epithelial cells in an open system. The results indicate better viability of the cells than in a closed system.

Steatorrhea, a simple and rapid method of diagnosis.

A simple and rapid method for the diagnosis of steatorrhea is described. The method is based on the assessment of the difference of specific gravity and lipophilic property between a normal stool and that in steatorrhea, using a benzene-NaBr system. The stool samples are dried, pulverized, and then investigated. Steatorrhea is defined either as a fat or more in a 24-hour sample. Stool samples of 71 infants and children were examined. Among these were 23 healthy subjects, 10 with upper respiratory tract infections, and 6 with pneumonia. A further 31 children had celiac disease, 9 of them were on a gluten-free diet, and one child had cystic fibrosis. The procedure described renders single stool samples suitable for the assessment of steatorrhea. As a screening test the method proved to be rapid and accurate in the diagnosis of steatorrhea.

Time function of corticosteroid levels in the blood plasma of rats under the influence of 222Rn inhalation.

The time function of cortocosteroid level in plasma of rats under two different 222Rn concentrations was investigated. Both curves show a maximum after 8h. Whereas the higher activity of 222Rn produces a second maximum after 5 days, the lower activity reaches its second maximum not before 9 days. From both time functions, a two-step mechanism in the intracellular control can be concluded.