The effects of dietary flaxseed on cardiac arrhythmias and claudication in patients with peripheral arterial disease 1.

Patients with peripheral artery disease (PAD) are at increased risk for cardiovascular events, and higher susceptibility for cardiac arrhythmias may be involved. The objectives of this double-blinded randomized controlled FLAX-PAD trial were to determine whether daily consumption of a diet supplemented with 30 g of milled flaxseed (or placebo) over 1 year by PAD patients has effects on the prevalence of cardiac arrhythmias and exercise capacity. Cardiac arrhythmias were assessed on a cardiac stress test and at rest. At baseline, the PAD patients had a high incidence of cardiac arrhythmias (48% in the flaxseed group and 32% in the placebo group). After 1 year, the presence of cardiac arrhythmias in the flaxseed group decreased by 2% and increased by 12% in the placebo group (P > 0.05). Electrocardiographic variables (P, PR, QRS, QT, and QTc) did not change in either group during the trial. Patients from both groups improved initial and absolute claudication distances but the intergroup difference was also not statistically significant. In summary, the prevalence of cardiac arrhythmias and physical capacity trended in a positive direction for patients ingesting flaxseed but either a larger sample size or a longer intervention with flaxseed may be required to show statistically significant differences.

Feasibility and Tolerability of Daily Pulse Consumption in Individuals with Peripheral Artery Disease.

The present study investigated the feasibility, tolerability, and adherence of daily consumption of whole pulses (dried beans, peas, lentils, chickpeas) by individuals with peripheral artery disease participating in an 8-week study. Study questionnaires and semi-structured interviews for 26 participants were used to determine prestudy pulse consumption and participants' experiences with respect to adherence, positive and negative effects, bowel routine, satiety, and enjoyment of the foods. Although the majority of participants rarely consumed pulses prior to the study, there was a high rate of adherence to daily consumption of the study foods for 8 weeks despite comments regarding study fatigue during the latter part of the study. Participants had no gastrointestinal side effects (42%) or experienced flatulence that resolved by week 4 (23%), whereas 62% reported improvements in their bowel pattern. By week 8 greater satiety was noted by some participants (19%), with the categories "less afternoon snacking" and "not snacking" receiving more responses. The key finding of this study was that consumption of pulses is a viable approach for this population; however, the frequency of consumption that is tolerable in the long term should be integrated with the dose and timeframe required to achieve and maintain health benefits.

Dietary flaxseed independently lowers circulating cholesterol and lowers it beyond the effects of cholesterol-lowering medications alone in patients with peripheral artery disease.

BACKGROUND: Dietary flaxseed lowers cholesterol in healthy subjects with mild biomarkers of cardiovascular disease (CVD). OBJECTIVE: The aim was to investigate the effects of dietary flaxseed on plasma cholesterol in a patient population with clinically significant CVD and in those administered cholesterol-lowering medications (CLMs), primarily statins. METHODS: This double-blind, randomized, placebo-controlled trial examined the effects of a diet supplemented for 12 mo with foods that contained either 30 g of milled flaxseed [milled flaxseed treatment (FX) group; n = 58] or 30 g of whole wheat [placebo (PL) group; n = 52] in a patient population with peripheral artery disease (PAD). Plasma lipids were measured at 0, 1, 6, and 12 mo. RESULTS: Dietary flaxseed in PAD patients resulted in a 15% reduction in circulating LDL cholesterol as early as 1 mo into the trial (P = 0.05). The concentration in the FX group (2.1 ± 0.10 mmol/L) tended to be less than in the PL group (2.5 ± 0.2 mmol/L) at 6 mo (P = 0.12), but not at 12 mo (P = 0.33). Total cholesterol also tended to be lower in the FX group than in the PL group at 1 mo (11%, P = 0.05) and 6 mo (11%, P = 0.07), but not at 12 mo (P = 0.24). In a subgroup of patients taking flaxseed and CLM (n = 36), LDL-cholesterol concentrations were lowered by 8.5% ± 3.0% compared with baseline after 12 mo. This differed from the PL + CLM subgroup (n = 26), which increased by 3.0% ± 4.4% (P = 0.030) to a final concentration of 2.2 ± 0.1 mmol/L. CONCLUSIONS: Milled flaxseed lowers total and LDL cholesterol in patients with PAD and has additional LDL-cholesterol-lowering capabilities when used in conjunction with CLMs. This trial was registered at clinicaltrials.gov as NCT00781950.

Female sex does not influence 30-day stroke and mortality rates after carotid endarterectomy.

BACKGROUND: Sex-based differences in outcomes for the treatment of carotid arterial disease remains a controversial topic. The main objective of this study was to determine if gender differences influence 30-day stroke and mortality rates after carotid endarterectomy (CEA) in a large series of patients. METHODS: This is a retrospective study of all patients undergoing endarterectomy performed by a single surgeon between January 1, 1993 and December 15, 2010. The analysis included data from 1,046 CEAs (683 men and 363 women). RESULTS: There were no differences found in 30-day stroke, death, or combined stroke and death rates between women and men. The 30-day stroke rate was 1.6% for women and 1.8% for men (P = 0.98), with no significant differences between asymptomatic patients (1.7% for women vs. 1.2% for men; P = 0.70) or symptomatic patients (1.6% for women vs. 2.1% for men; P = 0.74). The 30-day mortality rate was 0.8% for women and 0.9% for men (P = 0.85) with no significant differences between asymptomatic patients (0.8% for women vs. 1.2% for men; P = 0.77) and symptomatic patients (0.8% for women vs. 0.7% for men; P = 0.84). There was a similar low risk for the combined outcome of stroke and death (1.9% for women vs. 2.2% for men; P = 0.92), with no differences between asymptomatic patients (1.7% for women vs. 1.6% for men; P = 0.89) or symptomatic patients (2.1% for women vs. 2.5% for men; P = 0.84). CONCLUSIONS: Female sex does not influence 30-day stroke and mortality rates after CEA, regardless of preoperative symptom status.

Dietary Flaxseed Reduces Central Aortic Blood Pressure Without Cardiac Involvement but Through Changes in Plasma Oxylipins.

UNLABELLED: In the year-long FlaxPAD clinical trial (Flaxseed for Peripheral Artery Disease), dietary flaxseed generated a powerful reduction in brachial systolic and diastolic blood pressure in patients with peripheral artery disease. Oxylipins were implicated as potential mechanistic mediators. However, the ability of flaxseed to impact central aortic hypertension, arterial stiffness, or cardiac performance was not investigated. Additionally, the relationship between central blood pressure (cBP) and oxylipins was not elucidated. Therefore, radial tonometry and pulse wave analysis were used to measure cBP and cardiac function in the FlaxPAD population (n=62). Plasma oxylipins were analyzed with high-performance liquid chromatography mass spectrometry. In patients with high blood pressure at baseline, the average decrease in central systolic and diastolic blood pressures versus placebo was 10 and 6 mm Hg, respectively. Flaxseed did not significantly impact augmentation index or other cardiac function indices. Alternatively, the data support several specific oxylipins as potential mediators in the antihypertensive properties of flaxseed. For example, every 1 nmol/L increase in plasma 16-hydroxyeicosatetraenoic acid increased the odds of higher central systolic and diastolic blood pressures by 12- and 9-fold, respectively. Every 1 nmol/L increase in plasma thromboxane B2 and 5,6-dihydroxyeicosatrienoic acid increased the odds of higher cBP by 33- and 9-fold, respectively. Flaxseed induced a decrease in many oxylipins, which corresponded with a reduced risk of elevated cBP. These data extend the antihypertensive properties of flaxseed to cBP without cardiac involvement but rather through oxylipins. This study provides further support for oxylipins as therapeutic targets in hypertension. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00781950.

Daily non-soy legume consumption reverses vascular impairment due to peripheral artery disease.

OBJECTIVE: Peripheral artery disease (PAD) results from a decrease in blood flow to the limbs due to the presence of atherosclerotic plaque. It has been reported that isoflavones isolated from soybeans reduce arterial stiffness, a component of atherosclerotic disease. This study examined the effect of consuming whole legumes (non-soy) on arterial function in humans with PAD. METHODS: Twenty-six individuals with PAD consumed ½ cup/day cooked legumes (beans, peas, lentils, chickpeas) daily for 8 weeks. Measurements of circulating factors and vascular function at baseline and study conclusion were compared. RESULTS: No changes in were detected relative to baseline values for most parameters. Total and LDL-cholesterol were reduced by 5.0% and 8.7%, respectively. The ankle-brachial index (ABI) showed a 5.5% increase. Changes in ABI and LDL-cholesterol did not correlate. Serum markers of endothelial dysfunction and inflammation were unchanged, but short-chain acylcarnitine concentrations were significantly decreased. CONCLUSIONS: A legume-rich diet can elicit major improvements in arterial function and serum cholesterol in the absence of changes in either body mass or blood pressure, although the improvements in vascular function and serum lipids were unrelated. Although the positive results obtained with this dietary intervention were not explained by biomarkers of endothelial function and inflammation, altered acylcarnitine levels indicate an improvement in skeletal muscle metabolism due to enhanced tissue perfusion.

Potent antihypertensive action of dietary flaxseed in hypertensive patients.

Flaxseed contains ω-3 fatty acids, lignans, and fiber that together may provide benefits to patients with cardiovascular disease. Animal work identified that patients with peripheral artery disease may particularly benefit from dietary supplementation with flaxseed. Hypertension is commonly associated with peripheral artery disease. The purpose of the study was to examine the effects of daily ingestion of flaxseed on systolic (SBP) and diastolic blood pressure (DBP) in peripheral artery disease patients. In this prospective, double-blinded, placebo-controlled, randomized trial, patients (110 in total) ingested a variety of foods that contained 30 g of milled flaxseed or placebo each day over 6 months. Plasma levels of the ω-3 fatty acid α-linolenic acid and enterolignans increased 2- to 50-fold in the flaxseed-fed group but did not increase significantly in the placebo group. Patient body weights were not significantly different between the 2 groups at any time. SBP was ≈ 10 mm Hg lower, and DBP was ≈ 7 mm Hg lower in the flaxseed group compared with placebo after 6 months. Patients who entered the trial with a SBP ≥ 140 mm Hg at baseline obtained a significant reduction of 15 mm Hg in SBP and 7 mm Hg in DBP from flaxseed ingestion. The antihypertensive effect was achieved selectively in hypertensive patients. Circulating α-linolenic acid levels correlated with SBP and DBP, and lignan levels correlated with changes in DBP. In summary, flaxseed induced one of the most potent antihypertensive effects achieved by a dietary intervention.

Steal syndrome complicating upper extremity hemoaccess procedures: incidence and risk factors.

INTRODUCTION: Steal syndrome is a potentially grave complication of upper extremity hemoaccess (HA) in patients with renal failure. To determine the incidence and risk factors for steal in these patients at the St. Boniface Hospital, Winnipeg, a tertiary care centre for vascular surgery and dialysis, we reviewed data from patients requiring hemodialysis between September 1986 and July 2000. PATIENTS AND METHODS: We excluded all venous catheter and lower extremity procedures. There remained 325 upper extremity procedures in 217 patients. Data were collected from the patients' charts or by interview. First by univariate analysis and then by multivariate analysis for independent risk factors, we studied the effect on the development of steal of age, sex, race diabetes mellitus, hypertension, coronary artery disease or cerebrovascular disease, smoking, proximal procedures based on the brachial artery, distal procedures based on the radial artery, the use of prosthetic graft material and the creation of autologous fistulas. RESULTS: The incidence of steal was 6.2%. The significant independent risk factors were diabetes mellitus (odds ratio [OR] 5.00, 95% confidence interval [CI] 1.39-18.08, p = 0.01) and Aboriginal race (OR 3.59, 95% CI 1.07-12.04, p = 0.04). An increasing risk for each year of advancing age at the time of procedure was suggested but was not significant (OR 1.04, 95% CI 1.00-1.09 p = 0.07). CONCLUSIONS: Patients who are diabetic or Aboriginal are at increased risk for steal with upper extremity HA procedures. This knowledge can guide discussion of dialysis options and informed consent. If upper extremity HA procedures are undertaken in patients at risk, they should be closely monitored and early intervention applied if necessary.