Individuals at increased coronary heart disease risk are characterized by an impaired microvascular function in skin.
ABSTRACT To investigate whether microvascular function in skin is a valid model to study the relationships between cardiovascular risk factors and microvascular function, we investigated skin microvascular function in individuals with increased coronary heart disease (CHD) risk.
Forty-six healthy White individuals aged 30-70 years were studied. Coronary heart disease risk was assessed with the use of the CHD risk score according to the Framingham Heart Study, which is based on the risk factors age, blood pressure, cigarette smoking, total cholesterol, HDL cholesterol and diabetes. Endothelium-dependent and -independent vasodilation in skin were evaluated with laser Doppler after iontophoresis of acetylcholine and sodium nitroprusside. Videomicroscopy was used to measure recruitment of skin capillaries after arterial occlusion.
Coronary heart disease risk score (i.e. the 10-year probability of CHD) varied from 1-37%. Microvascular function decreased with increasing quartiles of CHD risk (for acetylcholine-mediated vasodilation: 687, 585, 420 and 326%, P = 0.002; for nitroprusside-mediated vasodilation: 776, 582, 513 and 366%, P = 0.02; for capillary recruitment: 49.9, 44.6, 27.2 and 26.7%, P = 0.001). These trends were similar in men and women (P for interaction > 0.2) and independent of body mass index.
Increased CHD risk is associated with an impaired endothelium-dependent vasodilatation and capillary recruitment in skin, suggesting that microvascular function in skin is a valid model to study the relationships between cardiovascular risk factors and microvascular function.
Article: Low fingertip temperature rebound measured by digital thermal monitoring strongly correlates with the presence and extent of coronary artery disease diagnosed by 64-slice multi-detector computed tomography.[show abstract] [hide abstract]
ABSTRACT: Previous studies showed strong correlations between low fingertip temperature rebound measured by digital thermal monitoring (DTM) during a 5 min arm-cuff induced reactive hyperemia and both the Framingham Risk Score (FRS), and coronary artery calcification (CAC) in asymptomatic populations. This study evaluates the correlation between DTM and coronary artery disease (CAD) measured by CT angiography (CTA) in symptomatic patients. It also investigates the correlation between CTA and a new index of neurovascular reactivity measured by DTM. 129 patients, age 63 +/- 9 years, 68% male, underwent DTM, CAC and CTA. Adjusted DTM indices in the occluded arm were calculated: temperature rebound: aTR and area under the temperature curve aTMP-AUC. DTM neurovascular reactivity (NVR) index was measured based on increased fingertip temperature in the non-occluded arm. Obstructive CAD was defined as >or=50% luminal stenosis, and normal as no stenosis and CAC = 0. Baseline fingertip temperature was not different across the groups. However, all DTM indices of vascular and neurovascular reactivity significantly decreased from normal to non-obstructive to obstructive CAD [(aTR 1.77 +/- 1.18 to 1.24 +/- 1.14 to 0.94 +/- 0.92) (P = 0.009), (aTMP-AUC: 355.6 +/- 242.4 to 277.4 +/- 182.4 to 184.4 +/- 171.2) (P = 0.001), (NVR: 161.5 +/- 147.4 to 77.6 +/- 88.2 to 48.8 +/- 63.8) (P = 0.015)]. After adjusting for risk factors, the odds ratio for obstructive CAD compared to normal in the lowest versus two upper tertiles of FRS, aTR, aTMP-AUC, and NVR were 2.41 (1.02-5.93), P = 0.05, 8.67 (2.6-9.4), P = 0.001, 11.62 (5.1-28.7), P = 0.001, and 3.58 (1.09-11.69), P = 0.01, respectively. DTM indices and FRS combined resulted in a ROC curve area of 0.88 for the prediction of obstructive CAD. In patients suspected of CAD, low fingertip temperature rebound measured by DTM significantly predicted CTA-diagnosed obstructive disease.The international journal of cardiovascular imaging 07/2009; 25(7):725-38. · 2.15 Impact Factor
Article: Reproducibility of non-invasive assessment of skin endothelial function using laser Doppler flowmetry and laser speckle contrast imaging.[show abstract] [hide abstract]
ABSTRACT: Endothelial dysfunction precedes atherosclerosis. Vasodilation induced by acetylcholine (ACh) is a specific test of endothelial function. Reproducibility of laser techniques such as laser-Doppler-flowmetry (LDF) and Laser-speckle-contrast-imaging (LSCI) to detect ACh vasodilation is debated and results expressions lack standardization. We aimed to study at a 7-day interval (i) the inter-subject reproducibility, (ii) the intra-subjects reproducibility, and (iii) the effect of the results expressions over variability. Using LDF and LSCI simultaneously, we performed two different ACh-iontophoresis protocols. The maximal ACh vasodilation (peak-ACh) was expressed as absolute or normalized flow or conductance values. Inter-subject reproducibility was expressed as coefficient of variation (inter-CV,%). Intra-subject reproducibility was expressed as within subject coefficients of variation (intra-CV,%), and intra-class correlation coefficients (ICC). Fifteen healthy subjects were included. The inter-subject reproducibility of peak-ACh depended upon the expression of the results and ranged from 55% to 162% for LDF and from 17% to 83% for LSCI. The intra-subject reproducibility (intra-CV/ICC) of peak-ACh was reduced when assessed with LSCI compared to LDF no matter how the results were expressed and whatever the protocol used. The highest intra-subject reproducibility was found using LSCI. It was 18.7%/0.87 for a single current stimulation (expressed as cutaneous vascular conductance) and 11.4%/0.61 for multiple current stimulations (expressed as absolute value). ACh-iontophoresis coupled with LSCI is a promising test to assess endothelial function because it is reproducible, safe, and non-invasive. N°: NCT01664572.PLoS ONE 01/2013; 8(4):e61320. · 4.09 Impact Factor
Article: Microvascular function is preserved in newly diagnosed rheumatoid arthritis and low systemic inflammatory activity.[show abstract] [hide abstract]
ABSTRACT: Rheumatoid arthritis (RA) is associated with increased cardiovascular morbidity and mortality. Microvascular function has been linked to several risk factors for cardiovascular disease and may be affected in RA. It is, however, presently unknown at what point in the disease course the abnormalities in microvascular function occur. We determined whether microvascular function is already disturbed in early disease-modifying antirheumatic drugs (DMARD)-naive RA patients with low systemic inflammation. Fifteen consecutive RA patients with a median symptom duration of 5 months, a C-reactive protein level of ≤20 mg/l and without a history of cardiovascular disease, and age 15 and sex-matched healthy controls were recruited. Endothelium-dependent and endothelium-independent vasodilatation in skin was evaluated with laser Doppler fluxmetry after iontophoresis of acetylcholine and sodium nitroprusside, respectively. Videomicroscopy was used to measure recruitment of skin capillaries after arterial occlusion. CRP and ESR levels were mildly, but significantly elevated in patients compared to controls. No differences in both endothelium-dependent vasodilatation and capillary recruitment were observed between groups [709% (95% CI, 457-961%) vs 797% (95% CI, 556-1,037%), P = 0.59 and 37% (95% CI, 26-47%) vs 41% (95% CI, 31-50%), P=0.59, respectively]. Skin microvascular function is preserved in early, DMARD-naive RA patients with moderately active RA but low systemic inflammatory activity. Both the extent of the systemic inflammation and disease duration, therefore, may be important determinants of microvascular dysfunction and subsequent increased risk for cardiovascular disease.Clinical Rheumatology 04/2011; 30(8):1113-8. · 2.00 Impact Factor