Contralateral differences in ankle SBP and pulse wave velocity: associations with incident heart failure and mortality.

BACKGROUND: Contralateral differences in brachial SBP are indicative of underlaying cardiovascular issues. OBJECTIVES: To examine the association of contralateral differences in ankle SBP, brachial-ankle pulse wave velocity (baPWV), and heart-ankle pulse wave velocity (haPWV) with incident heart failure and all-cause and cardiovascular mortality. METHODS: Cox proportional-hazards models were used to calculate hazard ratios and 95% confidence intervals (95% CIs) in 5077 participants (75 ±â€Š5 years) of the Atherosclerosis Risk in Communities study. RESULTS: Over a mean follow-up of 7.5 ±â€Š2.2 years, there were 457 heart failure events, 1275 all-cause and 363 cardiovascular deaths. Interankle SBP difference of at least 10 mmHg [hazard ratio = 1.12; confidence interval (CI) 1.00-1.28], at least 15 mmHg (hazard ratio = 1.21; CI 1.03-1.43), contralateral difference in baPWV more than 240 cm/s (hazard ratio = 1.22; CI 1.02-1.46), and haPWV more than 80 cm/s (hazard ratio = 1.24; CI 1.04-1.48) were each independently associated with all-cause mortality after adjustment for confounders. Contralateral differences in ankle SBP of at least 15 mmHg (hazard ratio = 1.56; CI 1.17-2.09), and haPWV more than 80 cm/s (hazard ratio = 1.42; CI 1.03-1.96) were both independently associated with cardiovascular mortality. Unadjusted analysis revealed that those with contralateral differences in ankle SBP of at least 10 and at least 15 mmHg, baPWV more than 240, and haPWV more than 80 cm/s had higher risks of heart failure (all P < 0.05). CONCLUSION: These results underscore the significance of evaluating contralateral differences in ankle SBP and PWV as potential markers of increased mortality risk among older adults.

Effectiveness of different recovery postures during high-intensity interval training.

BACKGROUND: High-intensity interval training (HIIT) has become a very popular mode of exercise practiced by the elite as well as recreationally active adults. The aim of this study was to evaluate the effects of four recovery postures that are typically used by exercisers on recovery rate and performance in subsequent bouts of HIIT. METHODS: Sixteen young, healthy adults performed four HIIT trials with randomized recovery postures. Each trial consisted of four sets of modified Wingate anaerobic power tests (20-sec duration) on a cycle ergometer (Monark 894E, Vansbro, Sweden) separated by four-minute recovery between each exercise set. Participants adopted one of four recovery postures immediately following each set: standing still with hands on the back of the head (head), standing still with hands resting on knees (knees), slow walking with hands on hips (walking), or supine rest (supine). Differences were assessed by a two-way (posture × set) repeated measures analysis of variance. RESULTS: Peak and mean anaerobic power progressively declined within each set (P<0.05), with no differences between postures. Fatigue rate was significantly slower during supine (59±12%) than knees (63±13%). Heart rate recovery was faster (P<0.001) during supine than the other three standing postures. Pulmonary ventilation was not significantly different between postures. Blood lactate concentrations measured after HIIT were not significantly different between postures. CONCLUSIONS: Supine posture appears to be more advantageous in facilitating recovery when compared to the three standing postures. None of the recovery postures examined was responsible for better performance in subsequent bouts of HIIT.

Estimated pulse wave velocity and incident heart failure and its subtypes: Findings from the multi-ethnic study of atherosclerosis.

Age-associated increase in aortic stiffness, measured as carotid-femoral pulse wave velocity (PWV), is an important effector of cardiac damage and heart failure (HF). Pulse wave velocity estimated from age and blood pressure (ePWV) is emerging as a useful proxy of vascular aging and subsequent cardiovascular disease risk. We examined the association of ePWV with incident HF and its subtypes in a large community sample of 6814 middle-aged and older adults from the Multi-Ethnic Study of Atherosclerosis (MESA). Methods: Participants with an ejection fraction ≤40 % were classified as HF with reduced ejection fraction (HFrEF) while those with an ejection fraction ≥50 % were classified as HF with preserved ejection fraction (HFpEF). Cox proportional hazards regression models were used to calculate hazard ratios (HR) and 95 % confidence intervals (CI). Results: Over a mean follow-up period of 12.5 years, incident HF was diagnosed in 339 participants: 165 were classified as HFrEF and 138 as HFpEF. In fully adjusted models, the highest quartile of ePWV was significantly associated with an increased risk of overall HF (HR 4.79, 95 % CI 2.43-9.45) compared with the lowest quartile (reference). When exploring HF subtypes, the highest quartile of ePWV was associated with HFrEF (HR 8.37, 95 % CI 4.24-16.52) and HFpEF (HR 3.94, 95 % CI 1.39-11.17). Conclusions: Higher ePWV values were associated with higher rates of incident HF and its subtypes in a large, diverse cohort of men and women.

Arterial stiffness and contralateral differences in blood pressure: The Atherosclerosis Risk in Communities (ARIC) study.

A large interarm difference in brachial systolic blood pressure (SBP) (≥10 or ≥15 mmHg) is strongly associated with elevated cardiovascular events and mortality. Evidence demonstrating whether such contralateral differences in SBP occur in ankle blood pressure and its association with arterial stiffness is scarce. The aims of this study were to characterize arm and ankle contralateral SBP differences in a sample of community-dwelling older adults (5077), and to determine whether this difference is associated with arterial stiffness assessed by pulse wave velocity (PWV) between the heart and ankle (haPWV), femoral artery and ankle (faPWV), and brachial artery and ankle (baPWV) in the right and left sides. Prevalence of interarm SBP differences ≥10 and ≥15 mmHg was 5.1% and .7%, respectively; the corresponding prevalence for interankle SBP was 24.9% and 12.0%. Higher BMI and lower ankle-brachial index (ABI) were significantly correlated with greater interarm SBP differences. Increased age, higher BMI, lower ABI, and greater contralateral differences in haPWV, faPWV, and baPWV were significantly correlated to greater interankle SBP differences. Interankle SBP difference ≥15 mmHg was significantly associated with contralateral differences of >80 cm/s in haPWV (OR = 1.94 [95% CI = 1.52-2.49]), >165 cm/s in faPWV (OR = 1.64 [95% CI = 1.27-2.12]), and >240 cm/s in baPWV (OR = 2.43 [95% CI = 1.94-3.05]). The associations remained significant after adjustment for age, sex, race, BMI, smoking status, and ABI. Compared with interarm differences, interankle differences in SBP are common in older adults. The magnitude of interankle, but not interarm, differences in SBP is associated with various measures of arterial stiffness.

Total brachial artery reactivity and incident heart failure and heart failure subtypes: multi-ethnic study of atherosclerosis.

Endothelial dysfunction may be a phenotypic expression of heart failure (HF). Total brachial artery reactivity (TBAR) is a non-invasive measurement of endothelial function that has been associated with increased risk of cardiovascular outcomes. Limited information is currently available on the impact of TBAR on incident HF and its subtypes. The aim of this study was to investigate whether TBAR is associated with overall incident HF, and the two HF subtypes, HF with reduced ejection fraction (HFrEF) and HF with preserved ejection fraction (HFpEF) in a community-based study. The sample included 5499 participants (45-84 years of age) from the Multi-Ethnic Study of Atherosclerosis who were free of cardiovascular disease at baseline. Brachial artery was imaged via ultrasound after five minutes of cuff occlusion at the right forearm. TBAR was calculated as the difference between maximum and minimum brachial artery diameters following cuff release, divided by the minimum diameter multiplied by 100%. A dichotomous TBAR variable was created based on the median value (below or above 7.9%). Participants with EF ≤ 40% were considered HFrEF and those with EF ≥ 50% were considered HFpEF. Cox proportional hazards regression models were used to calculate hazard ratios (HR) and 95% confidence intervals (CI). Over a mean follow-up period of 12.5 years, incident HF was diagnosed in 250 participants: 98 classified as HFrEF, 106 as HFpEF, and 46 with unknown or borderline EF (41-49%). Crude analysis revealed that those with TBAR below the median had a significantly greater risk of HF (HR 1.46; 95% CI 1.13-1.88, p < 0.01) and HFrEF (HR 1.61; 95% CI 1.07-2.43, p < 0.05). Following adjustment for known HF risk factors (e.g., age, sex, race, blood pressure), the strength of these relationships was attenuated. Borderline significant results were revealed in those with HFpEF (HR 1.43; 95% CI 0.97-2.12, p = 0.06). Kaplan-Meier curves suggest significantly lower risks of developing HF and HFrEF in those with TBAR above the median (log-rank p ≤ 0.05 for both). When examined as a continuous variable, with a cut point of 50% for EF, every 1-standard deviation (9.7%) increase in TBAR resulted in a 19 and 29% decrease in risk of HF (p < 0.05) and HFrEF (p = 0.05), respectively. Lower TBAR values were associated with higher rates of incident HF and HFrEF, suggesting a possible role of endothelial dysfunction in HF pathogenesis. The impact of other known HF risk factors may mediate this relationship, thus further research is warranted.