D. Rosenbaum

Assessment of left atrial function by MRI myocardial feature tracking

Left atrium (LA) volumes and function are predictors of cardiovascular events. Because LA function cannot be assessed from cardiovascular magnetic resonance imaging (MRI) using the well‐established left ventricular tagging techniques, we hypothesized that adequate feature tracking (FT) applied to conventional cine MRI data could characterize LA function accurately.

Mise au point et évaluation de l’ExSel Test pour dépister une consommation excessive de sel chez les patients hypertendus

OBJECTIVE Development of a test to screen excess salt intake (ESI) in hypertensive patients. METHODS Hypertensive subjects living in Paris area have been included. A 24-hour urinary sodium collection has been performed the day before the visit for a day hospital. A food diary was completed on the day of the urine collection and validated after an interview with a dietetician. An ESI was defined by a urinary sodium ≥ 200mmol/d. Clinical or food characteristics associated to an ESI were retained for the ExSel Test variables. A ROC curve was performed to determine the optimal score for the ExSel Test in detection of ESI in hypertensive patients. RESULTS One hundred and forty-eight hypertensive patients have been included living in the Île-de-France area. ESI was observed in 19% with a higher frequency in men. Seven major determinants of ESI have been identified and are the questions that constitute the ExSel Test. A positive response assigns points: man (1); BMI > 30 (2); bread 4 or 5 pieces per day (1) or more than 6 pieces; cheese at least 1 time per day (2); charcuterie at least 2 times per week (2); use of processed broth or pilaf (1); food rich in hidden salt (pizza, cheeseburger, quiche, shrimp, potato chips, smoked fish, olive) at least 2 times per week (1). The ROC curve analysis shows that a score of 5 or more has the best Youden index with a sensitivity of 0.63, specificity of 0.95, PPV of 0.75, NPV of 0.92. CONCLUSIONS In hypertensive subjects, an excessive salt intake can be detected by the realization of the ExSel Test based only on a simple food-questionnaire and some clinical parameters. For a clinical use of the ExSel Test, an electronic version is available on http://www.comitehta.org.

Retinal arteriolar remodeling evaluated with adaptive optics camera: Relationship with blood pressure levels

AIM To research a retinal arterioles wall-to-lumen ratio or lumen diameter cut-off that would discriminate hypertensive from normal subjects using adaptive optics camera. PATIENTS AND METHODS One thousand and five hundred subjects were consecutively recruited and Adaptive Optics Camera rtx1™ (Imagine-Eyes, Orsay, France) was used to measure wall thickness, internal diameter, to calculate wall-to-lumen ratio (WLR) and wall cross-sectional area of retinal arterioles. Sitting office blood pressure was measured once, just before retinal measurements and office blood pressure was defined as systolic blood pressure>=140mmHg and diastolic blood pressure>=90mmHg. ROC curves were constructed to determine cut-off values for retinal parameters to diagnose office hypertension. In another population of 276 subjects office BP, retinal arterioles evaluation and home blood pressure monitoring were obtained. The applicability of retinal WLR or diameter cut-off values were compared in patients with controlled, masked, white-coat and sustained hypertension. RESULTS In 1500 patients, a WLR>0.31 discriminated office hypertensive subjects with a 0.57 sensitivity and 0.71 specificity. Lumen diameter<78.2μm discriminated office hypertension with a 0.73 sensitivity and a 0.52 specificity. In the other 276 patients, WLR was higher in sustained hypertension vs normotensive patients (0.330±0.06 vs 0.292±0.05; P<0.001) and diameter was narrower in masked hypertensive vs normotensive subjects (73.0±11.2 vs 78.5±11.6μm; P<0.005). CONCLUSION A WLR higher than 0.31 is in favour of office arterial hypertension; a diameter under<78μm may indicate a masked hypertension. Retinal arterioles analysis through adaptive optics camera may help the diagnosis of arterial hypertension, in particular in case of masked hypertension.

Left atrium dysfunction by CMR in aortic valve stenosis

Background Cardiac Magnetic resonance (CMR) imaging is able to characterize with high accuracy left atrial (LA) size and volumes as well as dense myocardial fibrosis. The addition of functional parameters such as LA myocardial strain would enhance CMR usefulness for a comprehensive LA characterization. Our aim was to evaluate the ability of strain values obtained by CMR to characterize LA functional alterations in the setting of aortic valve stenosis (AVS).

CO-01: Retinal arterioles remodeling evaluated by adaptive optics camera in humans and its relationships with age, blood pressure and cardio-vascular risk factors

BACKGROUND Microvascular vessels and microvascular remodeling play a major role in blood pressure (BP) regulation and peripheral tissue oxygen delivery. The adaptive optics camera (AOC), a novel technique of fundus image analysis enables the noninvasive characterization of microvascular remodeling in the retina on a large scale. Our objective was to assess the role of Blood Pressure (BP), ageing, diabetes and other risk factors on retinal arteriolar remodeling using AOC. METHODS In 1.000 consecutive subjects in primary prevention with risk factors, we used the new RTX1(®) AOC (Imagine-Eyes, Orsay, France) and a semi-automated segmentation software to measure Wall Thickness (WT), Internal Diameter (ID) and to calculate Wall-to-Lumen Ratio (WLR) and Wall Cross Sectional Area (WCSA) on retinal arteriolar microvasculature. BP was assessed on standard conditions using oscillometric device during the AOC assessment. Hypertension was defined as the presence of Systolic BP>140mmHg and/or Diastolic BP>90mmHg. Standardized clinical and biological examinations were performed to assess for the presence of diabetes, dyslipidemia, obesity and current smoking which were defined according to guidelines. RESULTS Overall, ageing was associated with an increase in WLR due to sole WT increase. Subjects with office hypertension (n=313) had inward eutrophic remodeling with increased WLR (0.325±0.049 vs 0.292±0.056) due to higher WT, lower ID and overall stable WCSA. Diabetics (n=180) presented with hypertrophic remodeling indicated by higher WLR due to a significant increase in WT and WCSA concomitant to a normal BP. There was no significant remodeling associated with other cardiovascular risk factors. In multivariate analysis, BP and age remained independent positive correlates of WLR and WT whereas age had no influence on ID and only BP negatively correlated to ID CONCLUSIONS: Hypertension, age and diabetes are associated with increase in WLR and WT. Assessment OF WT and ID are mandatory to perform a correct interpretation of WLR increase. OAC could represent a promising tool for interventional studies on treatment-induced remodeling regression.

P4-33: Variations of retinal arteriolar wall-lumen ratio depend on mechanism of blood pressure changes

BACKGROUND A recently developed non-invasive opto-electronic technology (Adaptive Optics Camera, AOC) provides a morphologic analysis of the retinal arteriolar tree. Coupled with a validated semi-automated segmentation software it allows reproducible and reliable measurements of wall thickness (WT), internal diameter (ID), wall cross sectional area (WCSA) and calculation of wall-to-lumen ratio (WLR). Our aim was to assess the determinants of WLR along the temporal retinal artery and in case of acute Blood Pressure (BP) rise or drug-induced short term BP drop. METHODS We studied 3 groups of patients : 1/ We consecutively enrolled 48 patients and calculated WLR before the first bifurcation (parental vessel) and on its large and small post-bifurcation branches on the right eye temporal superior artery. 2/ In a subgroup of 10 patients WLR was measured at rest and right after exercise dynamic test. 3/ In 55 hypertensive subjects AOC assessment was repeated after a median of 49 days in 27 subjects with stable BP and 38 days in 28 subjects with a drop in BP secondary to antihypertensive drug adaptation. WT and ID were directly measured using non-invasive rtx1(®) AOC (ImagineEyes-Orsay, France) and a dedicated software analysis system was used to calculate WLR and WCSA. BP was measured at the time of AOC examination in standard conditions. Hypertension was defined as the presence of Systolic Blood Pressure (SBP)>140mmHg and/or Diastolic blood pressure (DBP)>90mmHg. RESULTS 1/ In the first group, in both normo- and hypertensive patients, a significant decrease in ID, WT and WCSA was observed on post-bifurcation branches whereas WLR remained constant (table 1, next page). 2/ In the second group, while SBP acutely increased of 47±8mmHg, ANOVA analysis did not show any significant changes in WLR. 3/ At 6 weeks, in the follow-up group with a short-term SBP drop (-19.3±7.7%), a decrease of WLR (-7.0±8.0mmHg) due to ID increase (+5.6±5.9%) without significant changes in WT and WSCA were observed. No changes were observed in the group with a stable BP (see table next page). CONCLUSIONS WLR, the index of remodeling in retinal small arteries, is constant along the arterial tree despite changes in WT and ID. While WLR did not change during acute exercise-induced BP surge, it decreased due to a ID increase after a short-term drug-induced BP drop. Those results confirm the homogeneity of remodeling along the retinal arteriolar tree and that mechanisms of BP changes have different effects on remodeling.

Left atrium wall tracking from MR images for strain assessment

M. Evin*, A. Redheuil, S. Hatem, D. Rosenbaum, K. Bouazizi-Verdier, A. De Cesare, P. Cluzel and N. Kachenoura Sorbonne Universités, UPMC Univ Paris 06, UMR 7371, UMR_S 1146, Laboratoire d’Imagerie Biomédicale, Paris, France; Université Pierre et Marie Curie-Paris 6, INSERM UMR_S956, Paris, France; ICAN Imaging Core Lab, Paris; Pitié Salpêtrière Cardiovascular Imaging, Paris, France; Imagerie par Résonance Magnétique Médicale et Multi-modalités, Université Paris-Sud, CNRS, UMR 8081, Orsay, France