Artery Research

Editorial Board

2010-03-01

Isolated systolic hypertension and the J-curve of cardiovascular disease risk

Stanley S. Franklin — 2010-02-16

Abstract: Controversy persists regarding the presence and significance of blood pressure “J-curves” of increased cardiovascular disease (CVD) risk as they relate to older people with isolated systolic hypertension (ISH). Age is an important effect modifier favoring diastolic blood pressure (DBP) in young adults, systolic blood pressure (SBP) in middle-aged, and pulse pressure (PP) in the elderly as predictors of CVD events. By contrast, a recent Framingham Heart Study showed that combined blood pressure components increased the prediction of CVD risk over any single blood pressure component. Interestingly, of the 4 blood pressure components [DBP, SBP, PP, and mean arterial pressure (MAP)] only DBP showed non-linear tendencies, which presented as a J-curve of increased CVD risk in this primary prevention study. A low DBP was associated with increased PP, and hence, was a marker for increased arterial stiffness; thus, risk was defined by increased PP that resulted in decreased DBP and increased SBP. On the other hand, when primary CVD events result in poor cardiac function, the presence of combined SBP and DBP J-curves serve as predictors of secondary CVD events—so called “reverse causality”; thus, risk is associated with decreased rather than by increased SBP. Lastly, treatment-induced cardiac risk is a potential third explanation for J-curves that occur in the presence of hemodynamically significant coronary artery stenosis. The thesis of this presentation is that a treatment-induced cardiac event, as an explanation for the J-curve risk, occurs infrequently as compared to arterial stiffness or reverse causality; furthermore, the exact point at which the J-curve begins, remains in doubt. Nevertheless, only a prospective trial with baseline and pre-event blood pressure determinations can establish the presence and frequency of treatment-induced J-curve risk.

Acute and chronic effects of acupuncture on radial artery: A randomized double blind study in migraine

2010-02-22

Abstract: Background: Acupuncture is an accepted treatment for migraine. Palpation of the radial pulses is one of the most important techniques in traditional Chinese medicine both for diagnosis and monitoring of treatment efficacy. The objective of the present study was to investigate the acute and chronic effects of acupuncture on the radial artery of patients suffering from severe migraine.Methods: A double-blind parallel group study was conducted in 31 patients never exposed to acupuncture and randomized in two groups : real acupuncture versus sham acupuncture, applied 3 times at one month interval. At baseline and after 2 months, radial artery diameter was measured with a high resolution echotracking system before and during a 20 min’s acupuncture session. Migraine severity was assessed by self administrated questionnaires and visual analogic scale for pain at each visit. Patients and investigators (not acupuncture physician) were blinded as to the treatment allocation.Results: During the first session, radial artery diameter significantly increased after real acupuncture, (+3.1% IQR [−3.2–8.5], P = 0.03 vs 0.9% IQR [−5.3–5.8], P = NS), and remained significantly higher after the two months treatment course 5.2% IQR [−3.9–14] vs. −4.4% IQR [−10.0–3.5], respectively; P < 0.01). Patients with the most severe pain at baseline were less prone to dilate their arteries during follow-up (P < 0.05). A larger arterial vasodilatation after real acupuncture was observed for any given level of pain intensity (P < 0.01).Conclusion: an acupuncture-induced vasodilatation was observed at the site of the radial artery in patients suffering from severe migraine and naïve to acupuncture. The vasodilatation was maintained after chronic treatment.Condensed abstract: This double-blind randomized, controlled trial aimed at showing the acute and chronic vasodilatory response to acupuncture in migrainers naïve to acupuncture. We show that real acupuncture is accompanied by acute and chronic vasodilation of the radial artery, the chronic vasodilation is inversely related to the level of pain at baseline.

Racial differences in relation between carotid and radial augmentation index

2010-01-21

Abstract: Background: Augmented central artery wave reflection is a cardiovascular disease risk factor. Augmentation index (AI) obtained from peripheral artery waveforms provides qualitatively similar information to AI from central artery waveforms. Little information is available, however, regarding the influence of racial difference in association between central and peripheral AI.Methods: We studied 47 White adults (45±17yr, 20 women) and 94 age-matched Asian adults (45±14yr, 42 women).Results: The White group was significantly taller than the Asian group, whereas there were no significant group differences in blood pressure and heart rate. Carotid and radial AI tended to be lower in White compared with Asian adults (P<0.10 for both). Such tendency disappeared when the difference in height was taken into account using ANCOVA (P=0.84 and P=0.77, respectively). Radial AI was strongly and positively correlated with carotid AI in White adults (r=0.75, P<0.0001) as well as in Asian adults (r=0.82, P<0.0001). The slope and intercept of linear regression line between radial and carotid AI of White adults were highly comparable with those of Asian adults.Conclusion: AI in the conveniently located peripheral vasculature may provide a surrogate measure of central AI irrespective of difference in race (e.g., Asian vs. White populations).

The assessment of carotid–femoral distance for aortic pulse wave velocity: Should it be estimated from body height?

Jan Filipovský, Otto Mayer, Milena Dolejšová, Jitka Seidlerová — 2010-02-12

Summary: Background: Aortic pulse wave velocity (PWV) can be biased by the measurement of carotid–femoral (c-f) distance on body surface. We wondered whether the estimation of distance according to body height could be used.Methods: Three cohorts of altogether 596 subjects (mean age 58.9 years) were studied. PWV was measured by Sphygmocor. The c-f distance was 1. measured by tape, 2. estimated from height which was multiplied by 0.29 (=median ratio of measured c-f distance to body height).Results: Difference in PWV calculated by the two methods (measuredminusestimated) increased with PWV: in 10th decile (>12.88m/s), it was on the average +0.8m/s. In multiple regression analysis, this difference depended highly significantly on PWV, weight and male gender (positive associations) and height (negative association); there were no associations with age, smoking, hypertension, diabetes, or presence of cardiovascular disease.Conclusions: The difference between measured and estimated value was mild even in subjects with the highest measured PWV and it was not influenced by the risk profile of the subjects. The estimated PWV values showed regression to the mean; this phenomenon could be due to lower precision of the estimation, but also due to false high measured values of the c-f distance in obese subjects. Estimation of c-f distance from body height would probably reduce bias due to body dysproportion. The best method of the distance assessment, however, must be determined in larger cohorts where the relationship to cardiovascular morbidity/mortality endpoints can be evaluated.

Multiple splenic artery aneurysms in a patient with idiopathic thrombocytopenic purpura: A case report, brief literature review and discussion

David Busel, Alonso Yanez, Edgard Jimenez, Christopher K. Johansen — 2010-01-07

Abstract: Multiple splenic artery aneurysms in a patient with idiopathic thrombocytopenic purpura: A case report, brief literature review and discussion.

Carotid–femoral pulse wave velocity: Impact of different arterial path length measurements

Jun Sugawara, Koichiro Hayashi, Takashi Yokoi, Hirofumi Tanaka — 2009-12-07

Abstract: Background: Carotid–femoral pulse wave velocity (PWV) is the most established index of arterial stiffness. Yet there is no consensus on the methodology in regard to the arterial path length measurements conducted on the body surface. Currently, it is not known to what extent the differences in the arterial path length measurements affect absolute PWV values.Methods: Two hundred fifty apparently healthy adults (127 men and 123 women, 19–79 years) were studied. Carotid–femoral PWV was calculated using (1) the straight distance between carotid and femoral sites (PWVcar–fem), (2) the straight distance between suprasternal notch and femoral site minus carotid arterial length (PWV(ssn–fem)−(ssn–car)), (3) the straight distance between carotid and femoral sites minus carotid arterial length (PWV(car–fem)−(ssn–car)), and (4) the combined distance from suprasternal notch to the umbilicus and from the umbilicus to femoral site minus carotid arterial length (PWV(ssn–umb–fem)−(ssn–car)).Results: All the calculated PWV were significantly correlated with each other (r=0.966–0.995). PWVs accounting for carotid arterial length were 16–31% lower than PWVcar–fem. PWVcar–fem value of 12m/s corresponded to 8.3m/s for PWV(ssn–fem)−(ssn–car), 10.0m/s for PWV(car–fem)−(ssn–car), and 8.9m/s for PWV(ssn–umb–fem)−(ssn–car).Conclusion: Different body surface measurements used to estimate arterial path length would produce substantial variations in absolute PWV values.