The Impaired Elasticity of Large Arteries in Systemic Sclerosis Patients

(1) Background: Systemic sclerosis (SSc) is an autoimmune disease characterized by endothelial dysfunction and fibrosis of skin and visceral organs. In the last decade, attention has been focused on the macrovascular involvement of the disease. In particular, the observation of increased arterial stiffness represented an interesting aspect of the disease, as predictor of cardiovascular risk. (2) Methods: We recruited 60 SSc patients (52 ± 12 years old, 90% females) and 150 age/sex-matched healthy controls in order to evaluate both intima-media thickness of the right common carotid artery and arterial stiffness using the B-mode echography and the SphygmoCor system® tonometer. (3) Results: The carotid-femoral pulse wave velocity (PWV) was higher in SSc patients than in controls (8.6 ± 1.7 vs. 7.8 ± 1.5 m/s; p < 0.001), as was the carotid-radial PWV (7.8 ± 1.1 vs. 6.7 ± 1.4 m/s; p < 0.001). The intima-media thickness was higher in SSc than in controls (654 ± 108 vs. 602 ± 118 µm; p = 0.004). The other parameters measured at carotid (radial strain, Young’s modulus, compliance and distensibility) all indicated that arterial stiffness in tension was more pronounced in SSc. Of interest, the direct correlation between PWV and age corresponded closely in SSc. Moreover, a significant difference between SSc and controls as regards the carotid parameters was evident in younger subjects. (4) Conclusions: SSc patients showed an increased arterial stiffness compared to healthy controls. In particular, an SSc-related pathologic effect was suggested by the more pronounced increase in PWV with age and lower values of carotid elasticity in younger SSc patients than in age-matched controls.

Carotid Beta Stiffness Association with Thyroid Function

Background: Thyroid hormone modulation of cardiovascular function has been associated with cardiovascular disease. Recent evidence suggests that free thyroxine (FT4) levels are associated with an increase in systemic arterial stiffness, but little is known about the effects of FT4 at the local level of the common carotid artery. β-stiffness index is a local elastic parameter usually determined by carotid ultrasound imaging. Methods: We conducted a cross-sectional analysis in the ProgeNIA cohort, including 4846 subjects across a broad age range. For the purpose of this study, we excluded subjects with increased thyrotropin (TSH) levels and those treated with levothyroxine or thyrostatic. We assessed β stiffness, strain, wall–lumen ratio, carotid cross-sectional area (CSA), and stress and flow in the right common carotid artery. We tested whether FT4, heart rate, and their interactions were associated with carotid parameters. Results: FT4 was positively and independently associated with β stiffness index (β = 0.026, p = 0.041), and had a negative association with strain (β = −0.025, p = 0.009). After adding heart rate and the interaction between FT4 and heart rate to the model, FT4 was still associated with the β stiffness index (β = 0.186, p = 0.06), heart rate was positively associated with the stiffness index (β = 0.389, p < 0.001) as well as their interaction (β = 0.271, p = 0.007). Conclusion: This study suggests that higher FT4 levels increase arterial stiffness at the common carotid level, consistent with a detrimental effect on elastic arteries. The effect of FT4 is likely to be primarily attributable to its effect on heart rate.

Speckle tracking carotid artery circumferential strain is a marker of arterial sclerosis but not coronary atherosis

PURPOSE

Circumferential speckle tracking carotid artery strain is a novel method of quantifying vessel wall stiffness. We hypothesized that carotid wall stiffness would be associated with carotid intimal medial thickening (a medial process associated with risk factors), but not coronary artery disease (an intimal process).

METHODS

Bilateral carotid artery ultrasound was conducted on outpatients who had previously undergone elective coronary angiography. Mean carotid artery far wall circumferential strain (FWCS) was assessed for correlations with coronary angiographic stenosis, cardiac risk factors, carotid intima-media thickness (CIMT), and carotid plaque.

RESULTS

One hundred and sixty five (165) patients were studied. No significant association was found between the presence of coronary artery disease on angiography and mean FWCS. FWCS was higher in current tobacco smokers. In addition, carotid strain was found to decrease with increased age (r = -0.33, P < 0.001). When adjusted for pulse pressure (PP), FWCS/PP was negatively correlated with mean CIMT (r = -0.29, P = 0.002) and bulb maximum plaque height (r = -0.27, P = 0.004). Hypertension and diabetes were associated with decreased FWCS/PP (increased wall stiffness).

CONCLUSIONS

While no clear relationship between carotid strain and coronary artery disease was observed, increased CIMT, carotid plaque, and cardiac risk factors were associated with decreased carotid strain. Further work is required to explore the relationship between carotid strain and cardiovascular events.

Carotid strain measurement in patients with pseudoxanthoma elasticum - Hint for a different pathomechanism?

Pseudoxanthoma Elasticum (PXE), caused by autosomal-recessive mutations in the ATP-binding cassette transporter (ABCC6) gene, is known for high prevalence of atherosclerosis. A novel method investigating elastic properties of arteries in atherosclerotic patients is vascular strain analysis. We compared 44 PXE patients with peripheral artery disease (PXE+PAD group) with 50 control patients, each 25 without (control group) and with PAD (PAD group). All participants underwent an angiological examination including ankle-brachial index (ABI) and were examined with speckle-tracking based vascular strain analysis of common carotid arteries, measuring radial displacement (r.Dis), radial velocity (r.Vel), radial strain (r.Str), circumferential strain (c.Str), radial strainrate (r.SR) and circumferential strainrate (c.SR). We found significant lower ABI in patients with PXE compared to all other groups (each p < 0.01). The vascular strain analysis resulted in significantly decreased values in the PAD group compared to PXE with PAD (each p ≤ 0.01) and controls without PAD (each p ≤ 0.05), whereas no significant difference could be found between PXE+PAD and controls without PAD. We found significant negative correlations between low strain values and a higher prevalence of PAD in non-PXE patients (r.Str r = -0.34; c.Str r = -0.35; r.SR: r = -0.51; c.SR: r = -0.53). In conclusion, PXE patients had similar values for arterial stiffness compared to controls without PAD in vascular strain analysis. In this group, arterial stiffness parameters were significantly higher compared to non-PXE PAD patients. It is worth to discuss whether PAD-like manifestations in PXE are a different kind of disease and might need another strategy in diagnostics and therapy.

Modulation of carotid strain by statin therapy in atherosclerosis patients

BACKGROUND

The beneficial effect of statin therapy on the progress of atherosclerotic disease has been demonstrated by numerous studies. Vascular strain imaging is an arising method to evaluate arterial stiffness. Our study examined whether an influence of statin therapy on the vessel wall could be detected by vascular strain imaging.

PATIENTS AND METHODS

88 patients with recently detected atherosclerosis underwent an angiological examination including ankle-brachial index (ABI), pulse wave index (PWI), central puls ewave velocity and duplex ultrasound. Captures for vascular strain analysis were taken in B-mode during ultrasound examination of the common carotid artery and evaluated using a workstation equipped with a speckle tracking based software. A statin therapy was recommended and after six months a follow-up examination took place. Meanwhile, the non-adherence of a group of patients (N = 18) lead to a possibility to observe statin effects on the vascular strain.

RESULTS

In the statin non-adherent group the ABI decreased significantly to a still non-pathological level (1.2 ± 0.2 vs. 1.0 ± 0.2; p = 0.016) whereas it stagnated in the adherent group (1.0 ± 0.2 vs. 1.0 ± 0.2; p = 0.383). The PWI did not differ in the non-adherent group (180.5 ± 71.9 vs. 164.4 ± 75.8; p = 0.436) but under statin therapy it decreased significantly (261.8 ± 238.6 vs. 196.4 ± 137.4; p = 0.016). In comparison to the adherent group (4.2 ± 2.0 vs. 4.0 ± 1.8; p = 0.548) under statin therapy the radial strain decreased significantly in the non-adherent group (4.7 ± 2.0 vs. 3.3 ± 1.1; p = 0.014).

CONCLUSIONS

Our findings reveal a beneficial influence of statin therapy on the arterial wall detected by vascular strain analysis.