Ari Lieber

Aortic wave reflection in women and men

Augmentation index (AIx), a marker of the number of aortic wave reflections (AWRs), is influenced not only by the magnitude of incident and reflected pressure waves but also by the time of return. A new triangulation method has been developed, enabling us to better quantify AWRs and to determine their sex differences, which may relate to body size or pulse pressure (PP) amplification, measured from the brachial PP-to-carotid PP (B/C) ratio. With the use of pulse wave analysis, AWRs were evaluated in 51 women and 72 men treated for hypertension and studied in relationship to age, blood pressure, and pulse wave velocity. When women were compared with men, AIx (expressed in %PP and adjusted to heart rate) was significantly higher, together with a significant decrease of the B/C ratio and an increase of the reflection magnitude and of the amplitude (but not the timing) of the backward pressure wave. The significance of the amplitude difference between men and women was enhanced after an adjustment to heart rate or pulse wave velocity but was abolished after an adjustment to body height or the B/C ratio. In the overall population, AIx and the reflection magnitude index were positively (r(2) = 0.39) and independently associated, after excluding confounding factors such as drug treatment. In conclusion, when compared with men, women treated for hypertension have increased AIx, related to the increased amplitude, and not timing, of backward pressure waves. This finding relates to sex differences in body size and mostly brachial-carotid PP amplification, a parameter highly related to the sex difference of cardiovascular risk.

Hypertension, Diabetes Type II, and Their Association: Role of Arterial Stiffness

In patients with both hypertension and type II diabetes, the systolic blood pressure (SBP) increases linearly with age, while that of diastolic blood pressure (DBP) declines curvilinearly as early as age 45, all suggesting the development of increased arterial stiffness. Increased stiffness is an important, independent, and significant risk predictor in subjects with hypertension and diabetes. In patients with both diseases, stiffness assessed at the same mean arterial pressure (MAP) was significantly higher in diabetic patients. Arterial stiffness is related to age, heart rate (HR), and MAP, but in diabetic patients, it also related to diabetes duration and insulin treatment (IT). In the metabolic syndrome (MetSyn), diabetes also acts on the small arteries through capillary rarefaction to reduce the effective length of the arterial tree, increases the reflected pulse wave and thus the pulse pressure (PP). These studies indicate that diabetes and hypertension additively contribute to increased pulsatility and suggest that any means to reduce stiffness would be beneficial in these conditions.

Cardiac and arterial calcifications and all-cause mortality in the elderly: The PROTEGER Study

OBJECTIVE To investigate the association of overall mortality with the presence and extent of cardiovascular calcifications. METHODS We investigated the association of cardiac (mitral annulus, aortic valve) and arterial calcifications (abdominal aorta, carotid and femoral arteries) by ultrasonography, with all-cause mortality in a population of 331 high-risk elderly subjects (86.8 ± 6.9 years). After a mean follow-up of 378 days, 110 deaths occurred. RESULTS A simple calcification score, defined by the presence of cardiac and arterial calcifications, was significantly associated with all-cause mortality (HR=1.47, 95% CI: 1.08-1.99), independent of low plasma albumin, increased plasma glucose and creatinine, as well as low diastolic blood pressure. Moreover, arterial calcifications showed negligible prognostic value with a high prevalence >89%, while cardiac calcifications significantly predicted overall mortality (HR=1.92, 95% CI: 1.28-2.87) at a prevalence of 36%. In another Cox regression, mitral annular calcification was proved to be a significant predictor of total mortality (HR=1.61, 95% CI: 1.02-2.54). CONCLUSION The independent association between the extent of calcification and all-cause mortality is consistently significant in this frail elderly population. Arterial calcification presents a very high prevalence but a low predictive value, whereas in cardiac calcification, prevalence is lower but predictive value is much higher.

Cardiovascular prevention: relationships between arterial aging and chronic drug treatment

Drugs acting on cardiovascular (CV) prevention are, by definition, interconnected with age-induced arterial changes. However, this question has been poorly investigated along long-term treatment. This goal requires a major prerequisite: to determine statistical links associating age-induced changes in arterial stiffness and wave reflections with drug classes acting on CV prevention. We studied 347 subjects where CV prevention involved hypertension, diabetes mellitus and hypercholesterolaemia; and included six drug classes: diuretics, β-blocking agents, angiotensin II (ANGII) and calcium-channel (CCB) blockers, insulin therapy and statins. For each class, the total population was divided into two subgroups according to the presence or absence of the corresponding class. Statistical comparisons between subgroups involved brachial and central blood pressure measurements, aortic pulse wave velocity (PWV), augmentation index (AIx), used as a marker of wave reflections. Non-invasive measurements included tonometry and pulse wave analysis. Appropriate adjustments indicated among results the respective role of age, sex, mean blood pressure (MBP), standard risk factors and other confounding variables. CCB and statins did not exhibit statistical association with PWV or AIx. β-Blocking agents were significantly linked with heart rate reduction and resulting increase in AIx and central pulse pressure (PP). Increased PWV independent of age, MBP, CV risk factors were noticed under diuretics, ANGII blockers and insulin, pointing to intrinsic modifications of the arterial wall. Treatment of CV prevention involves alterations of the arterial wall depending on drug class. β-Blocking agents and insulin are associated with the higher increases of central PP.

Predictive factors for all-cause mortality in the hospitalized elderly subject: The importance of arrhythmia

BACKGROUND In elderly patients traditional cardiovascular (CV) risk factors are poorly correlated with mortality and few data are available on determinants and consequences of supra-ventricular arrhythmia. In a cohort of 331 hospitalized elderly patients (mean age+/-SD=85+/-7 years), we assessed which CV characteristics were associated with all-cause mortality. AIM OF THE STUDY We wished to determine whether the presence of arrhythmia was associated with an increase of overall mortality in the hospitalized elderly population, and to ascertain which factors were associated with arrhythmia, in order to better understand the underlying mechanisms of both arrhythmia and arrhythmia-related mortality in these patients. RESULTS The relative hazard for overall mortality in the presence of arrhythmia was 2.40 (95% CI: 1.41-4.07; p<0.001), independent of major confounding factors, compared to sinus rhythm. Both arrhythmia and low DBP were independent predictors of mortality but no association or interaction between arrhythmia and DBP was observed. The left atrium diameter was found to be a predictor of arrhythmia, and when entered in the Cox regression analysis, it suppressed arrhythmia from the model predicting all-cause mortality. CONCLUSION In the hospitalized elderly, arrhythmia is an independent predictor of all-cause mortality, and left atrium size is an independent predictor of both arrhythmia and mortality, suggesting that links exist. Therapeutic management could therefore focus more on prevention of heart structure remodelling than on traditional risk factors.

Quelle stratégie de prévention chez l’hypertendu ?

L’hypertension arterielle se situe en bonne position parmi les facteurs de risque cardiovasculaire et son controle efficace n’est actuellement atteint que dans un quart des cas, alors qu’elle est responsable de 7 millions de deces annuels dans le monde. La pression arterielle systolique ainsi que la pression diastolique, mais aussi la pression pulsee sont les parametres essentiels et il est montre qu’aux facteurs de risque traditionnellement cites doivent s’en ajouter de nouveaux tels que l’hyperhomocysteinemie ou l’augmentation de la CRP. La reduction de la pression arterielle s’obtient par les mesures hygieno-dietetiques ainsi que par un traitement pouvant etre issu de 7 familles medicamenteuses avec differentes recommandations specifiques a la presentation clinique et biologique, le tout faisant partie integrante du programme global de reduction du risque cardiovasculaire, en particulier le risque coronaire et les complications du diabete. De plus, nous decouvrons que l’aspirine et les statines amenent une reduction du risque cardiovasculaire encore plus importante chez le sujet hypertendu, qui doit etre considere comme patient a risque eleve et dont l’objectif tensionnel optimal doit etre atteint.