Abstract Objective The primary aim of the study was to assess whether both the amount and pace of daily walking were associated with circulating antioxidant capacity in symptomatic patients with ...peripheral artery disease (PAD). Methods Community-based walking was measured in 244 men and women who were limited by symptomatic PAD during a 1-week period in which they wore an ankle-mounted step activity monitor. Patients were further characterized by circulating antioxidant capacity with the OxiSelect (Cell Biolabs Inc, San Diego, Calif) hydroxyl radical antioxidant capacity (HORAC) activity assay. Results To assess the amount of walking, patients were grouped into low (≤2440 strides/d), middle (2441-3835 strides/d), and high (>3835 strides/d) stride tertiles. HORAC was higher in the middle ( P = .03) and high ( P = .01) stride tertiles than in the low tertile, but there was no difference between middle and high tertiles ( P = .44). To assess the pace of walking, patients were grouped into slow (<25.0 strides/min), middle (25.0-31.6 strides/min), and fast (>31.6 strides/min) cadence tertiles. HORAC was higher in the high cadence tertile than in the low ( P < .01) and middle ( P < .01) tertiles, but there was no difference between low and middle tertiles ( P = .48). Similar findings were obtained on group differences in HORAC after adjusting for age, sex, race, and ankle-brachial index for both the amount and pace of daily walking. Conclusions Walking >2440 strides each day and walking at a cadence faster than 31.6 strides/min for 30 minutes each day are both associated with greater circulating antioxidant capacity in symptomatic patients with PAD. The clinical significance is that a home-based walking program may be one approach to increase endogenous antioxidant capacity.
Abstract Background Peripheral artery disease (PAD) is a highly prevalent disease that impairs walking ability. Walking tests, such as the 6-minute walk test (6MWT) and 4-meter walk test, are ...commonly used to assess exercise endurance and ambulatory function over a short distance, respectively. The 6MWT performance is predictive of PAD severity and disease outcomes, but it is not feasible in many clinical settings because it requires a long walkway to serve as the test route and lengthens clinic visits. As an alternative, the 4-meter walk test is convenient, inexpensive, and repeatable, but whether it accurately predicts endurance performance in the long-distance 6MWT is not known. The goal of this study was to develop a statistical model to predict 6MWT gait speed from 4-meter walk test results and clinical characteristics among patients with PAD. Methods Measures of 6MWT gait speed were derived from 183 patients with symptomatic PAD who were evaluated at the University of Oklahoma Health Sciences Center (2004-2012). The testing procedures and research personnel remained constant throughout the duration of the study. Independent variables included demographic and clinical information and 4-meter walk test gait speed. Fivefold cross validation and manual backward selection were used for model selection. Adjusted R2 and corrected Akaike information criterion were applied to quantify the predictive performance of the regression models. Results A total of 183 people (54% male; mean age, 65 standard deviation (SD), 10 years) with moderate PAD severity (ankle-brachial index ABI; mean, 0.72 SD, 0.24) performed the walking tests. Participants covered an average distance of 335 (SD, 97) m distance in the 6MWT. The 4-meter walk gait speed, ABI, and dyspnea were independent predictors of 6MWT speed in the multivariate model (adjusted R2 = 0.55). The model resulted in 95% prediction interval widths of 30 m for mean and 260 m for individual predicted 6MWT distance measures. Conclusions Slower 4-meter walking speed, lower ABI, and presence of dyspnea all predict slower 6MWT gait speed, which corresponds to shorter 6MWT distance. Prediction of group means is reasonably precise; however, prediction of individual patient 6MWT performance is imprecise relative to between-group differences that are clinically important.
Objective Time spent in sedentary behavior has been associated with worse inflammation and cardiometabolic biomarkers in various populations. However, the association between time spent in sedentary ...behavior and biomarkers remains unknown in patients with intermittent claudication. The aim of the current study was to analyze the relationship between sedentary behavior and inflammatory and cardiometabolic biomarkers in patients with symptomatic peripheral arterial disease (PAD). Methods The sample included 297 patients with intermittent claudication. Sedentary behavior was assessed using a step activity monitor. Biomarkers of inflammation, oxidative stress, lipid profile, insulin resistance, and endogenous fibrinolysis were assessed. Demographic data, body mass index, physical activity status, and measures of severity of PAD (ankle-brachial index, peak walking time, and ischemic window) also were obtained. Results Time spent in sedentary behavior was related with high-sensitivity C-reactive protein ( b = 0.187; P = .005), glucose ( b = 0.238; P < .001), fibrinogen ( b = 0.167; P = .017), plasminogen activator inhibitor 1 activity ( b = 0.143; P = .036), and high-density lipoprotein cholesterol ( b = −0.133; P = .029). After adjustment for sex, age, physical activity status, body mass index, and severity of PAD, sedentary behavior remained related with high-sensitivity C-reactive protein ( b = 0.170; P = .015), glucose ( b = 0.178; P = .004), fibrinogen ( b = 0.189; P = .010), and high-density lipoprotein cholesterol ( b = −0.128; P = .032). Conclusions Time spent in sedentary activities was associated with worse inflammatory and cardiometabolic profile in patients with intermittent claudication.
Abstract
Deep vein thrombosis (DVT) is a prevalent disease. About 20 to 30% of patients with DVT will develop postthrombotic syndrome (PTS) within months after the initial diagnosis of DVT. There is ...no gold standard for diagnosis of PTS, but clinical signs include pitting edema, hyperpigmentation, phlebectatic crown, venous eczema, and varicose veins. Several scoring systems have been developed for diagnostic evaluation. Conservative treatment includes compression therapy, medications, lifestyle modification, and exercise. Compression therapy, the mainstay and most proven noninvasive therapy for patients with PTS, can be prescribed as compression stockings, bandaging, adjustable compression wrap devices, and intermittent pneumatic compression. Medications may be used to both prevent and treat PTS and include anticoagulation, anti-inflammatories, vasoactive drugs, antibiotics, and diuretics. Exercise, weight loss, smoking cessation, and leg elevation are also recommended. Areas of further research include the duration, compliance, and strength of compression stockings in the prevention of PTS after DVT; the use of intermittent compression devices; the optimal medical anticoagulant regimen after endovascular therapy; and the role of newer anticoagulants as anti-inflammatory agents.
Heart Failure with reduced ejection fraction (HFrEF) is a major cause of morbidity and mortality. Endothelial dysfunction is common in HFrEF. We propose a novel non-invasive stimulation of vagus ...nerve via direct low-level tragus stimulation (LLTS) as a potential to improve endothelial function in HFrEF. Effects of LLTS mimic direct vagal stimulation, which is proven to reduce sympathetic drive and nitric oxide synthesis. We conducted a first in human pilot clinical study to investigate the effects of LLTS on endothelial function.
We enrolled 20 patients with HFrEF in a randomized, double-blinded crossover study. The cohort characteristics were: 75%-male, 65%-Caucasians, Ischemic etiology-80%, HTN-65%, Diabetes-20%, ICD- 60%. All patients had LVEF<40% and were on standard medical therapies for HFrEF. Patients underwent experimental (Tragus stimulation) or sham(ear lobule) LLTS for 60 minutes, and endothelial function/microcirculation was assessed with laser speckle contrast imaging (LSCI) before and after each LLTS session. For microcirculation/endothelial function measurements, we utilized a technique similar to flow-mediated dilation protocol to induce functional hyperemia in forearm using an arterial cuff inflated to pressure of 50mm above current systolic BP over the brachial artery for 5 minutes. LLTS was achieved through direct Tragus stimulation using SALUSTIM device (20Hz, 200-microsecond pulse width). Stimulation energy level was set at the lowest possible level to ensure patient comfort (range 5-40mA, Figure 1A). On day 2, patients were crossed to the other arm. Microcirculation/endothelial function was evaluated as a fold change of maximal perfusion during post-occlusive reactive hyperemia over the baseline perfusion before occlusion. (Figure 1B). Statistical analysis was performed using Mann Whitney U test; p-value <0.05 was considered significant.
Experimental LLTS for 60 minutes resulted in the improved microcirculation/endothelial function when measured using LSCI in nail beds Figure 1C, 1.78±0.17 vs. 2.47±0.27, p<0.05), while sham stimulation had no significant effect (Figure 1D, 2.12±0.27 vs. 2.14±0.18, p=NS). No adverse events were reported and all patients tolerated the short-term stimulation without pain or discomfort.
Our first human pilot study demonstrated the beneficial effects of neuromodulation/LLTS on microcirculation/endothelial function in patients with HFrEF. Larger studies are underway to further validate these findings.
Unmasking a Giant Ventricular Pseudoaneurysm Gopalakrishnan, Mukesh, MD; Aruni, Bhavith, MD; Silva-Palacios, Federico, MD ...
Journal of the American College of Cardiology,
09/2012, Volume:
60, Issue:
11
Journal Article
Peer reviewed
Open access
Coronary angiography showed severe 2-vessel disease involving proximal right and left circumflex arteries, large posterior aneurysm (C,Online Videos 1 and 2) and overall LV ejection fraction of 25%.
Peripheral artery disease (PAD) is a vascular pathology with high prevalence among the aging population. PAD is associated with decreased cognitive performance, but the underlying mechanisms remain ...obscure. Normal brain function critically depends on an adequate adjustment of cerebral blood supply to match the needs of active brain regions via neurovascular coupling (NVC). NVC responses depend on healthy microvascular endothelial function. PAD is associated with significant endothelial dysfunction in peripheral arteries, but its effect on NVC responses has not been investigated. This study was designed to test the hypothesis that NVC and peripheral microvascular endothelial function are impaired in PAD. We enrolled 11 symptomatic patients with PAD and 11 age- and sex-matched controls. Participants were evaluated for cognitive performance using the Cambridge Neuropsychological Test Automated Battery and functional near-infrared spectroscopy to assess NVC responses during the cognitive
-back task. Peripheral microvascular endothelial function was evaluated using laser speckle contrast imaging. We found that cognitive performance was compromised in patients with PAD, evidenced by reduced visual memory, short-term memory, and sustained attention. We found that NVC responses and peripheral microvascular endothelial function were significantly impaired in patients with PAD. A positive correlation was observed between microvascular endothelial function, NVC responses, and cognitive performance in the study participants. Our findings support the concept that microvascular endothelial dysfunction and neurovascular uncoupling contribute to the genesis of cognitive impairment in older PAD patients with claudication. Longitudinal studies are warranted to test whether the targeted improvement of NVC responses can prevent or delay the onset of PAD-associated cognitive decline.
Peripheral artery disease (PAD) was associated with significantly decreased cognitive performance, impaired neurovascular coupling (NVC) responses in the prefrontal cortex (PFC), left and right dorsolateral prefrontal cortices (LDLPFC and RDLPFC), and impaired peripheral microvascular endothelial function. A positive correlation between microvascular endothelial function, NVC responses, and cognitive performance may suggest that PAD-related cognitive decrement is mechanistically linked, at least in part, to generalized microvascular endothelial dysfunction and subsequent impairment of NVC responses.
The aims of this investigation were to determine whether the daily dietary intake of nutrients by patients with peripheral artery disease (PAD) and intermittent claudication (IC) met recommended ...levels for adults older than 50 years and to determine whether meeting recommended levels of nutrients was associated with ankle-brachial index (ABI), inflammation, and ambulation of patients with PAD and IC.
A total of 48 patients were assessed on their dietary intake of 20 nutrients during a 3-day period. Patients were further characterized on demographic variables, comorbid conditions, cardiovascular risk factors, ABI, 6-minute walk distance (6MWD), and high-sensitivity C-reactive protein (hsCRP) concentration.
Few patients met the daily recommended intakes for calcium (4%), fiber (6%), vitamin E (6%), trans fatty acids (13%), vitamin A (15%), total sugars (19%), potassium (23%), sodium (29%), saturated fat (29%), and vitamin C (31%), and none of the patients met the daily recommended intake of vitamin D (0%). Overall, patients met few of the 20 dietary recommendations as the median score was seven recommendations. Only 17 of 48 patients met more than seven of the recommendations. For the ABI regression model adjusted for age, sex, race, smoking, hypertension, dyslipidemia, body mass index, and percentage body fat, the only significant predictor was total sugars (P < .001); patients who did not meet the recommendation had lower ABI values. For the hsCRP-adjusted regression model, the strongest significant predictor was omega-3 polyunsaturated fatty acids (P = .001), indicating that those who did not meet the recommendation had higher hsCRP values. Finally, for the 6MWD-adjusted regression model, folate (P = .011) and dietary score index (P = .014) were significant predictors; those who did not meet the recommendation for folate and those who met 5 or fewer of the 20 recommendations had shorter 6MWD.
Patients with PAD and IC consume a low-nutrient-dense diet that is deficient in many vitamins, calcium, fruits, and vegetables and contains too much added sugar, saturated and trans fats, and processed foods. In addition, more severe PAD, greater inflammation, and ambulatory dysfunction are independently associated with aspects of a low-nutrient-dense diet, such as too much intake of added sugars, low intake of omega-3 polyunsaturated fatty acids and folate, and meeting the recommended intakes of only five or fewer nutrients.
PURPOSE:We compared the prevalence of participants with and without symptomatic peripheral artery disease (PAD) who met the goals of attaining >7000 and 10 000 steps/d, and we determined whether PAD ...status was significantly associated with meeting the daily step count goals before and after adjusting for demographic variables, comorbid conditions, and cardiovascular risk factors.
METHODS:Participants with PAD (n = 396) and without PAD (n = 396) were assessed on their walking for 7 consecutive days with a step activity monitor.
RESULTS:The PAD group took significantly fewer steps/d than the non-PAD control group (6722 ± 3393 vs. 9475 ± 4110 steps/d; P < .001). Only 37.6% and 15.7% of the PAD group attained the goals of walking >7000 and 10 000 steps/d, respectively, whereas 67.9% and 37.4% of the control group attained these goals (P < .001 for each goal). Having PAD was associated with a 62% lower chance of attaining 7000 steps/d than compared with the control group (OR = 0.383; 95% CI, 0.259-0.565; P < .001), and a 55% lower chance of attaining 10 000 steps/d (OR = 0.449; 95% CI, 0.282-0.709; P < .001). Significant covariates (P < .01) included age, current smoking, diabetes, and body mass index.
CONCLUSIONS:Participants with symptomatic PAD had a 29% lower daily step count compared with age- and sex-matched controls, and were less likely to attain the 7000 and 10 000 steps/d goals. Additionally, participants who were least likely to meet the 7000 and 10 000 daily step count recommendations included those who were older, currently smoked, had diabetes, and had higher body mass index.
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