Arterial stiffness changes in patients with cardiovascular risk factors but normal carotid intima-media thickness

Brachial and carotid hemodynamic response to hot water immersion in men and women

This study sought to compare the brachial and carotid hemodynamic response to hot water immersion (HWI) between healthy young men and women. Ten women (W) and 11 men (M) (24 ± 4 yr) completed a 60-min HWI session immersed to the level of the sternum in 40°C water. Brachial and carotid artery hemodynamics (Doppler ultrasound) were measured at baseline (seated rest) and every 15 min throughout HWI. Within the brachial artery, total shear rate was elevated to a greater extent in women [+479 (+364, +594) s^-1] than in men [+292 (+222, +361) s^-1] during HWI (P = 0.005). As shear rate is inversely proportional to blood vessel diameter and directly proportional to blood flow velocity, the sex difference in brachial shear response to HWI was the result of a smaller brachial diameter among women at baseline (P < 0.0001) and throughout HWI (main effect of sex, P < 0.0001) and a greater increase in brachial velocity seen in women [+48 (+36, +61) cm/s] compared with men [+35 (+27, +43) cm/s] with HWI (P = 0.047) which allowed for a similar increase in brachial blood flow between sexes [M: +369 (+287, +451) mL/min, W: +364 (+243, +486) mL/min, P = 0.943]. In contrast, no differences were seen between sexes in carotid total shear rate, flow, velocity, or diameter at baseline or throughout HWI. These data indicate the presence of an artery-specific sex difference in the hemodynamic response to a single bout of HWI.

Subclinical left ventricular dysfunction assessed by two-dimensional speckle tracking echocardiography in asymptomatic patients with carotid stenosis

The relationship between subclinical left ventricular (LV) dysfunction and atherosclerosis may have been underestimated in the past, which might be responsible for the high incidence of premature death in individuals with carotid stenosis. We sought to evaluate the underlying myocardial dysfunction in asymptomatic carotid stenosis patients using speckle tracking echocardiography (STE). Fifty patients with carotid stenosis ≥ 50% and a preserved LV ejection fraction (LVEF), and 45 controls without carotid stenosis who were matched in terms of vascular comorbidities were enrolled. All participants underwent carotid ultrasound and echocardiographic examination. The global LV longitudinal strain (GLS) was measured using STE. Compared with the control group, the e' of the mitral annular velocity and GLS were decreased in asymptomatic carotid stenosis patients (p < 0.05), however, the LVEF was well preserved. Based on a predefined cutoff for subclinical LV systolic dysfunction that was defined at a GLS <  - 18%, this dysfunction was detected in 22 patients with carotid stenosis (44%) and in 10 patients in the control group (22%) (p < 0.05). The GLS was negatively correlated with the levels of low-density lipoprotein cholesterol (r =  - 0.356, p < 0.05) and triglyceride (r =  - 0.396, p < 0.05). In conclusion, LV diastolic and systolic functioning were significantly decreased in patients with asymptomatic carotid stenosis, and dyslipidemia likely contributed to the subclinical LV dysfunction in these patients. Our findings indicated the importance of detecting LV subclinical dysfunction and early intervention in this patient population.

Arterial stiffness and mitral regurgitation in arterial hypertension: an intriguing pathophysiological link

BACKGROUND

We examined the relative impact of arterial stiffness on the presence and/or severity of chronic mitral regurgitation (MR) in hypertensive patients.

METHODS

We prospectively enrolled 141 untreated hypertensive patients (mean age 56.6 ± 11.5 years): 94 with MR, 47 without MR. As a measure of arterial stiffness, pulse wave velocity (PWV) was assessed by applanation tonometry. Assessment of MR severity was obtained through calculation of effective regurgitant orifice area (EROA) and vena contracta by standard two-dimensional transthoracic echocardiography.

RESULTS

PWV appears to progressively increase according to the presence and severity of MR (no MR = 7.3 ± 1.1 m/s, mild MR = 7.9 ± 1.3 m/s, moderate MR = 9.0 ± 1.7 m/s, severe MR = 13.3 ± 4.1 m/s; P < 0.001 for all comparisons). EROA was positively correlated with age (P = 0.011), left atrial volume index (P = 0.023), PWV (P < 0.001) and augmentation index (P < 0.001), and negatively correlated with left ventricular ejection fraction (P = 0.002) and heart rate (HR) (P = 0.018). On stepwise multivariate logistic regression analysis, only PWV (OR = 2.87, 95% CI 1.750-4.738, P < 0.001) and HR (OR = 0.94, 95% CI 0.895-0.994, P = 0.02) appeared to be independent predictors of severe MR. Receiver operating characteristic curves showed that a cutoff of 9 m/s for PWV provided the best sensitivity/specificity for predicting both the presence of any degree of MR (sensitivity 73%, specificity 87%, AUC = 0.863; P < 0.001) and MR severity (sensitivity 100%, specificity 81%, AUC = 0.954; P < 0.001).

CONCLUSION

Reduced arterial elasticity because of increased stiffness may be an important marker for the presence and severity of MR in hypertensive patients.

Carotid Artery Stiffness and Development of Hypertension in People with Paraplegia and No Overt Cardiovascular Disease: A 7-year Follow-up Study

Objectives

The aim of this study was to compare arterial stiffness between people with paraplegia and able-bodied persons (ABPs) and to assess cardiovascular markers that may be predictive of the development of arterial hypertension in people with spinal cord injury (SCI).

Setting

This study was conducted at rehabilitation Hospital, Udine (Italy).

Methods

Fifty-seven patients with SCI were prospectively enrolled and compared with 88 healthy ABPs. All patients underwent comprehensive transthoracic echocardiography, and one-point left common carotid artery (CCA) color-Doppler study for arterial stiffness.

Results

Patients with SCI had significantly lower body mass index (BMI) and diastolic blood pressure (BP) compared with ABPs, and significantly higher carotid stiffness values (and lower arterial compliance) (P < 0.05) after adjustment for age, sex, BMI, physical activity, and heart rate. The SCI patients had lower values of the right ventricular function parameters (tricuspid annular plane systolic excursion and right Sm; P < 0.0001), increased wall thickness, and impaired diastolic function. At 7-year follow-up, 10.5% of SCI patients showed high BP; they were significantly heavier with a tendency toward increased abdominal obesity after adjustment for age and systolic BP. BMI was found to be an independent predictor of the development of hypertension.

Conclusions

Patients with posttraumatic chronic SCI and no overt cardiovascular disease exhibit higher CCA stiffness along with the left and right ventricular involvement, compared with ABPs. People with paraplegia who develop arterial hypertension show increased CCA stiffness mediated by obesity. Lifestyle modifications and weight control should be promoted in all patients with SCI, even at a very early stage.

Subclinical cardiovascular disease assessment and its relationship with cardiovascular risk SCORE in a healthy adult population: A cross-sectional community-based study

INTRODUCTION

The aim of this study is to evaluate the relationship and the accuracy of SCORE (Systematic Coronary Risk Evaluation Project) risk correlated to multiple methods for determining subclinical cardiovascular disease (CVD) in a healthy population.

MATERIAL AND METHODS

This cross-sectional study included 120 completely asymptomatic subjects, with an age range 35-75 years, and randomly selected from the general population. The individuals were evaluated clinically and biochemical, and the SCORE risk was computed. Subclinical atherosclerosis was assessed by various methods: carotid ultrasound for intima-media thickness (cIMT) and plaque detection; aortic pulse wave velocity (aPWV); echocardiography - left ventricular mass index (LVMI) and aortic atheromatosis (AA); ankle-brachial index (ABI).

RESULTS

SCORE mean value was 2.95±2.71, with 76% of subjects having SCORE <5. Sixty-four percent of all subjects have had increased subclinical CVD changes, and SCORE risk score was correlated positively with all markers, except for ABI. In the multivariate analysis, increased cIMT and aPWV were significantly associated with high value of SCORE risk (OR 4.14, 95% CI: 1.42-12.15, p=0.009; respectively OR 1.41, 95% CI: 1.01-1.96, p=0.039). A positive linear relationship was observed between 3 territories of subclinical CVD (cIMT, LVMI, aPWV) and SCORE risk (p<0.0001). There was evidence of subclinical CVD in 60% of subjects with a SCORE value <5.

CONCLUSIONS

As most subjects with a SCORE value <5 have subclinical CVD abnormalities, a more tailored subclinical CVD primary prevention program should be encouraged.

Carotid artery intima-media thickness and stiffness index β changes in normal children: role of age, height and sex

AIMS

The need for early markers of atherosclerosis in paediatric ages has been emphasized recently. Few data are available on the behaviour of carotid intima-media thickness (cIMT) and arterial stiffness in normal children.

METHODS

We studied prospectively 131 healthy children (78 boys), aged 3-16 years, by high-definition ultrasonography and echo-tracking technique in order to evaluate cIMT and stiffness index β.

RESULTS

Stiffness index β underwent a significant age-related increase (P < 0.001), and a positive relationship between cIMT and height was found in boys. In addition, stiffness index β and cIMT were not related to each other (P = 0.97).

CONCLUSION

This study provides information about two markers of subclinical atherosclerosis, cIMT and carotid stiffness index β, in normal children aged 3-16 years. We found a significant age-related and height-related increase of stiffness index β in both sexes, whereas cIMT was positively related to height only in boys.

Comparison of arterial stiffness/compliance in the ascending aorta and common carotid artery in healthy subjects and its impact on left ventricular structure and function

Arterial stiffness and compliance parameters from two adjacent elastic arteries [aorta and common carotid artery (CCA)] were compared and their relationship with left ventricular (LV) structure and function and clinical parameters was assessed. 584 healthy subjects were prospectively enrolled [mean age 47.8 ± 18.4 years, range 16-94; 318 (54.4%) men]. They underwent comprehensive transthoracic echocardiography; M-mode diameters were measured at the level of the ascending aorta in systole and diastole and by echo-tracking at the level of the left CCA. The β-stiffness, pressure-strain elastic modulus, arterial compliance and one-point pulse wave velocity were derived. A significant correlation was observed between aortic and CCA stiffness and compliance parameters (p < 0.0001 for all). At multiple regression analysis, CCA stiffness parameters were constantly correlated with age and systolic blood pressure, and accounted for up to 56% of the variability (vs. only 29% in aortic stiffness and compliance). CCA stiffness parameters were found to better predict LV structure, diastolic function than aortic stiffness parameters. Aortic and CCA stiffness and compliance were found to correlate with each other and with age, with the correlation being higher for CCA stiffness. At multiple regression analysis, CCA stiffness parameters were better predictors of LV structure and function than aortic stiffness.

Passive heat therapy improves endothelial function, arterial stiffness and blood pressure in sedentary humans

KEY POINTS

A recent 30 year prospective study showed that lifelong sauna use reduces cardiovascular-related and all-cause mortality; however, the specific cardiovascular adaptations that cause this chronic protection are currently unknown. We investigated the effects of 8 weeks of repeated hot water immersion ('heat therapy') on various biomarkers of cardiovascular health in young, sedentary humans. We showed that, relative to a sham group which participated in thermoneutral water immersion, heat therapy increased flow-mediated dilatation, reduced arterial stiffness, reduced mean arterial and diastolic blood pressure, and reduced carotid intima media thickness, with changes all on par or greater than what is typically observed in sedentary subjects with exercise training. Our results show for the first time that heat therapy has widespread and robust effects on vascular function, and as such, could be a viable treatment option for improving cardiovascular health in a variety of patient populations, particularly those with limited exercise tolerance and/or capabilities.

ABSTRACT

The majority of cardiovascular diseases are characterized by disorders of the arteries, predominantly caused by endothelial dysfunction and arterial stiffening. Intermittent hot water immersion ('heat therapy') results in elevations in core temperature and changes in cardiovascular haemodynamics, such as cardiac output and vascular shear stress, that are similar to exercise, and thus may provide an alternative means of improving health which could be utilized by patients with low exercise tolerance and/or capabilities. We sought to comprehensively assess the effects of 8 weeks of heat therapy on biomarkers of vascular function in young, sedentary subjects. Twenty young, sedentary subjects were assigned to participate in 8 weeks (4-5 times per week) of heat therapy (n = 10; immersion in a 40.5°C bath sufficient to maintain rectal temperature ≥ 38.5°C for 60 min per session) or thermoneutral water immersion (n = 10; sham). Eight weeks of heat therapy increased flow-mediated dilatation from 5.6 ± 0.3 to 10.9 ± 1.0% (P < 0.01) and superficial femoral dynamic arterial compliance from 0.06 ± 0.01 to 0.09 ±0.01 mm(2)  mmHg(-1) (P = 0.03), and reduced (i.e. improved) aortic pulse wave velocity from 7.1 ± 0.3 to 6.1 ± 0.3 m s(-1) (P = 0.03), carotid intima media thickness from 0.43 ± 0.01 to 0.37 ± 0.01 mm (P < 0.001), and mean arterial blood pressure from 83 ± 1 to 78 ± 2 mmHg (P = 0.02). No changes were observed in the sham group or for carotid arterial compliance, superficial femoral intima media thickness or endothelium-independent dilatation. Heat therapy improved endothelium-dependent dilatation, arterial stiffness, intima media thickness and blood pressure, indicating improved cardiovascular health. These data suggest heat therapy may provide a simple and effective tool for improving cardiovascular health in various populations.