Gender differences in the extent and timing of the reflected arterial waveform in the presence of coronary artery disease.

BACKGROUND: The non-invasive assessment of arterial dysfunction may improve cardiovascular (CV) risk assessment. We studied the relationship of the reflected wave transit time (RWT) and augmentation index (AIX), both derived from pulse wave analysis (PWA), in the presence/absence of coronary artery disease (CAD), and compared PWA with the ankle-brachial index (ABI). METHODS: A trained research nurse measured PWA (radial applanation tonometry, SphygmoCor device) and ABI (hand-held Doppler) in a consecutive series of fasted patients resting supine prior to elective coronary angiography. Measurements were undertaken blind to other clinical information. Mean differences in RWT, AIX, and ABI in the presence of CAD were adjusted for age, height, mean BP, fasting cholesterol, ever smoked, and treated hypertension using multiple linear regression. RESULTS: We recruited 125 patients (49 women) with a mean age of 65 years, total cholesterol 4.4 mmol/l, BP 136/78, current smokers 22%, and previous myocardial infraction 30%. A statistically significant interaction between sex and CAD was present for both RWT (p = 0.003) and AIX (p = 0.03). No interaction was demonstrated for ABI (p = 0.21). Mean differences for men and women in the presence/absence of CAD were: RWT -10.1 vs. +5.2 milliseconds; AIX +1.2 vs. -5.4; ABI -0.02 vs. -0.10. Male and female area under receiver operating characteristic curves for CAD detection differed for RWT (0.33 vs. 0.67) and AIX (0.62 vs. 0.36), but were similar for ABI (0.40 vs. 0.34). CONCLUSION: The timing and extent of arterial wave reflections in the presence of CAD may differ in men and women.

Relationship between arterial dysfunction and extra-articular features in patients with rheumatoid arthritis.

Systemic inflammation may be a common process that underpins both atherosclerosis and extra-articular features (ExRA) of rheumatoid arthritis (RA). We evaluated the relationship between ExRA and arterial dysfunction in 114 consecutive patients with RA (82% women) without overt arterial disease aged 40-65 years. A trained research nurse undertook 'SphygmoCor' pulse wave analysis (PWA) using radial applanation tonometry to measure the extent (augmentation index, AIX%) and timing (reflected wave transit time, RWT, msec) of aortic wave reflection. Assessment included fasting blood sample, patient questionnaire and medical record review. Mean differences were adjusted for age, sex, mean blood pressure, smoking pack-years, fasting cholesterol, Stanford HAQ score and erythrocyte sedimentation rate. Mean age was 54 (SD 7) and median RA duration 10 (IQR 4-17) years. There was a trend for arterial dysfunction (higher AIX%; lower RWT) to increase as the number of ExRA features rose, but no difference in AIX% (-0.5, 95%CI -2.8 to 1.8, P = 0.65) or RWT (0.3 ms, 95%CI -3.6 to 4.2, P = 0.86) between 'any ExRA' and 'no ExRA'. Arterial dysfunction was not associated with the presence of rheumatoid nodules, Sjogren's syndrome or carpal tunnel syndrome. Our study was too small to determine whether severe ('Malmo') ExRA (vasculitis, pericarditis, episcleritis) was truly associated with a higher AIX% (3.8, 95%CI -2.3 to 9.9, P = 0.22) and lower RWT (-5.5 ms 95%CI -13.1 to 2.1, P = 0.16). While arterial dysfunction may be associated with the number of ExRA features and severe ExRA, it does not appear to be associated with other ExRA features.

Relationship between arterial stiffness and Stanford Health Assessment Questionnaire disability in rheumatoid arthritis patients without overt arterial disease.

OBJECTIVE: To quantify the relationship between Stanford Health Assessment Questionnaire (HAQ) disability and arterial stiffness in patients with rheumatoid arthritis (RA). METHODS: A consecutive series of 114 patients with RA but without overt arterial disease, aged 40-65 years, were recruited from rheumatology clinics. A research nurse measured blood pressure (BP), arterial stiffness (heart rate-adjusted augmentation index), fasting lipids, glucose, erythrocyte sedimentation rate (ESR), and rheumatoid factor (RF). A self-completed patient questionnaire included HAQ, damaged joint count, EuroQol measure of health outcome, and Godin physical activity score. Multiple linear regression (MLR) adjusted for age, sex, smoking pack-years, cholesterol, mean arterial BP, physical activity, daily fruit and vegetable consumption, arthritis duration, ESR, and RA criteria. RESULTS: Mean age was 54 years (81% women) with a median HAQ of 1.13 (interquartile range 0.50; 1.75). Median RA duration was 10 years, 83% were RF-positive, and median ESR was 16 mm/h. Mean arterial stiffness was 31.5 (SD 7.7), BP 125/82 mm Hg, cholesterol 5.3 mmol/l, and 24% were current smokers. Current therapy included RA disease-modifying agents (90%), prednisolone (11%), and antihypertensive therapy (18%). Arterial stiffness was positively correlated with HAQ (r = 0.42; 95% CI 0.25 to 0.56). On MLR, a 1-point increase in HAQ disability was associated with a 2.8 increase (95% CI 1.1 to 4.4; p = 0.001) in arterial stiffness. Each additional damaged joint was associated with a 0.17 point increase (95% CI 0.04 to 0.29; p = 0.009) in arterial stiffness. The relationship between EuroQol and arterial stiffness was not statistically significant. CONCLUSION: In patients with RA who are free of overt arterial disease, higher RA disability is associated with increased arterial stiffness independently of traditional cardiovascular risk factors and RA characteristics.

Arterial stiffness and cumulative inflammatory burden in rheumatoid arthritis: a dose-response relationship independent of established cardiovascular risk factors.

OBJECTIVE: To quantify the relationship between arterial stiffness and cumulative inflammatory burden in patients with RA. METHODS: We recruited RA patients without overt arterial disease aged 40-65 years, attending hospital rheumatology outpatient clinics. Standardized research nurse assessment included blood pressure (BP), pulse wave analysis (PWA, SphygmoCor), BMI, fasting blood sample (lipids, glucose, RF and ESR), patient questionnaire (smoking, alcohol, diet, exercise, family history of premature coronary heart disease and Stanford HAQ), current medication and medical record review. Cumulative inflammatory burden was measured as ESR area-under-the-curve (ESR-years) extracted from medical records. Arterial stiffness was measured using PWA [aortic augmentation index (AIX@75)]. Multiple linear regression was used to adjust for age, sex and nine other cardiovascular risk factors. RESULTS: We recruited 114 RA patients (mean age 54 years, female 81%, current DMARD 90%, current NSAID 70%, ACR criteria 56%) comprising 1040 RA person-years. Cholesterol, glucose and BMI were similar in women and men. Women had a longer duration of arthritis (10 vs 7 years) and were more likely to be seropositive (85 vs 71%). BP, smoking and alcohol consumption were lower for women. On fully adjusted analysis, an increase of 100 ESR-years was associated with an increase in AIX@75 of 0.51 (95% CI 0.13, 0.88). On fully adjusted analysis restricted to women the increase was 0.43 (95% CI 0.01, 0.85). CONCLUSIONS: In RA patients free of overt arterial disease, a dose-response relationship exists between cumulative inflammatory burden and arterial stiffness. This relationship is independent of established CV risk factors.

Repeatability of central aortic blood pressures measured non-invasively using radial artery applanation tonometry and peripheral pulse wave analysis.

OBJECTIVE: To estimate the repeatability of radial pulse wave analysis (PWA) in measuring central systolic and diastolic blood pressures (cSBP/cDBP), pulse pressure (cPP), augmentation pressure (cAP) and pulse pressure amplification (PPA). METHODS: After 15 min supine rest, 20 ambulant patients (aged 27-82 years; four female) underwent four SphygmoCor PWA measurements on a single occasion. Two nurses independently undertook two measurements in alternate order, blind to their colleague's measurements. Analysis was by Bland-Altman limits of agreement (LOA). RESULTS: Heart rate and brachial blood pressure (BP) were stable during assessment. Based on the average of two PWA measurements between-observer differences (LOA, mean difference +/- 2SD) were small (cSBP 1.5 +/- 10.9 mmHg; cDBP 0.4 +/- 5.2 mmHg; cAP 0.5 +/- 4.5 mmHg; cPP 1.1 +/- 10.5 mmHg; PPA -0.5% +/- 5.6%). Between-observer differences were much greater for single/initial PWA measurement (cSBP 3.6 +/- 15.9 mmHg; cDBP 2.8 +/- 8.8 mmHg; cAP 0.7 +/- 5.8 mmHg; cPP 0.8 +/- 13.6 mmHg; PPA -1.2 +/- 9.4%). Within-observer LOA were very similar for both nurse A (cSBP -4.2 +/- 14.1 mmHg; cDBP -4.6 +/- 13.1 mmHg; cAP -0.4 +/- 4.4 mmHg; cPP 0.5 +/- 11.0 mmHg; PPA 0.7% +/- 9.0%) and nurse B (cSBP 0.0 +/- 12.1 mmHg; cDBP 0.2 +/- 8.5 mmHg; cAP -0.1 +/- 4.4 mmHg; cPP -0.2 +/- 11.9 mmHg; PPA -0.7% +/- 10.6%). CONCLUSION: Non-invasive assessment of central aortic pressures using PWA on a single occasion is highly repeatable in ambulant patients even when used by relatively inexperienced staff.

Indices of cardiovascular function derived from peripheral pulse wave analysis using radial applanation tonometry: a measurement repeatability study.

Pulse wave analysis (PWA) using applanation tonometry is a non-invasive technique for assessing cardiovascular function. It produces three important indices: ejection duration index (ED%), augmentation index adjusted for heart rate (AIX@75), and subendocardial viability ratio (SEVR%). The aim of this study was to assess within- and between-observer repeatability of these measurements. After resting supine for 15 minutes, 20 ambulant patients (16 male) in sinus rhythm underwent four PWA measurements on a single occasion. Two nurses (A & B) independently and alternately undertook PWA measurements using the same equipment (Omron HEM-757; SphygmoCor with Millar hand-held tonometer) blind to the other nurse's PWA measurements. Within- and between-observer differences were analysed using the Bland-Altman ;limits of agreement' approach (mean difference +/- 2 standard deviations, 2SD). Mean age was 56 (blood pressure, BP 136/79; pulse rate 64). BP/PWA measurements remained stable during assessment. Based on the average of two PWA measurements the mean +/- 2SD between-observer difference in ED% was 0.3 +/- 2.0; AIX@75 1.0 +/- 3.9; and SEVR% 1.7 +/- 14.2. Based on a single PWA measurement the between-observer difference was ED% 0.3 +/- 3.3; AIX@75 1.7 +/- 6.9; and SEVR% 0.6 +/- 22.6. Within-observer differences for nurse-A were ED% 0.0 +/- 5.4; AIX@75 1.5 +/- 7.0; and SEVR% 1.7 +/- 39.0 (nurse-B: 0.1 +/- 3.8; 0.1 +/- 8.0; and 0.6 +/- 23.3, respectively). PWA demonstrates high levels of repeatability even when used by relatively inexperienced staff and has the potential to be included in the routine cardiovascular assessment of ambulant patients.

Curing of pit & fissure sealants using Light Emitting Diode curing units.

Light Emitting Diode (LED) curing units are attractive to clinicians, because most are cordless and should create less heat within tooth structure. However, questions about polymerization efficacy have surrounded this technology. This research evaluated the adequacy of the depth of cure of pit & fissure sealants provided by LED curing units. Optilux (OP) and Elipar Highlight (HL) high intensity halogen and Astralis 5 (A5) conventional halogen lights were used for comparison. The Light Emitting Diode (LED) curing units were Allegro (AL), LE Demetron I (DM), FreeLight (FL), UltraLume 2(UL), UltraLume 5 (UL5) and VersaLux (VX). Sealants used in the study were UltraSeal XT plus Clear (Uclr), Opaque (Uopq) and Teethmate F-1 Natural (Kclr) and Opaque (Kopq). Specimens were fabricated in a brass mold (2 mm thick x 6 mm diameter) and placed between two glass slides (n=5). Each specimen was cured from the top surface only. One hour after curing, four Knoop Hardness readings were made for each top and bottom surface at least 1 mm from the edge. The bottom to top (B/T) KHN ratio was calculated. Groups were fabricated with 20 and 40-second exposure times. In addition, a group using a 1 mm-thick mold was fabricated using an exposure time of 20 seconds. Differences between lights for each material at each testing condition were determined using one-way ANOVA and Student-Newman-Keuls Post-hoc test (alpha=0.05). There was no statistical difference between light curing units for Uclr cured in a 1-mm thickness for 20 seconds or cured in a 2 mm-thickness for 40 seconds. All other materials and conditions showed differences between light curing units. Both opaque materials showed significant variations in B/T KHN ratios dependent upon the light-curing unit.