Gilles Soulat

Associations between native myocardial T1 and diastolic function evaluated by PC-CMR in patients with severe aortic valve stenosis

Background To assess the relationship between the presence of myocardial interstitial fibrosis as reflected by the increase in native T1 values and alterations in left ventricular (LV) diastolic function evaluated by phase contrast cardiac magnetic resonance (PC-CMR), in subjects with severe aortic valve stenosis (AVS). Methods We studied 20 subjects (71±10 years) with severe AVS including 19 with a preserved ejection fraction. All patients underwent transthoracic echocardiogram (TTE) and cardiac magnetic resonance (CMR) exams. CMR included conventional LV systolic function and delayed enhancement evaluations as well as a native T1 mapping acquisition using the modified Look-Locker inversion recovery sequence and velocity encoding data of the transmitral inflow for the evaluation of LV diastolic function. These latter CMR data were analyzed using custom software resulting in segmental T1 values and diastolic parameters such as transmitral peak velocities (E, A), peak flow rates (Ef, Af), filling volume (FV), and myocardial peak velocities. Results For all patients, TTE revealed the presence of severe AVS according to ESC criteria (aortic valve area indexed to BSA= 0.43±0.09 cm2/m2 and mean gradient 54 ±14mmHg). When compared to CMR data of 34 elderly controls (60±8 years) despite the preserved ejection fraction (patients=66±10%; controls=66±4%), diastolic parameters indicated an impaired LV relaxation in patients with severe AVS. Importantly, while dense fibrosis volume quantified from delayed enhancement images was not related to diastolic function parameters, a significant relation was found between native myocardial T1 values and parameters of LV filling such as: the ratio between the peak filling rate and the peak atrial rate EfMR/AfMR (r=0.51; p<0.05); the ratio between the peak atrial rate and the filling volume Af/FVMR (r=0.67; p<0.05); and the peak atrial rate Af (r=0.63; p<0.05). Conclusions Interstitial myocardial fibrosis assessed non-invasively by native T1 is related to the severity of diastolic dysfunction in subjects with severe AVS.

Reply to Comment on ‘Numerical assessment and comparison of pulse wave velocity methods aiming at measuring aortic stiffness’

Dear editor, dear referees, please find below the point to point responses to the review of our reply on comments (RE: PMEA-102395) entitled: NUMERICAL ASSESSMENT AND COMPARISON OF PULSE WAVE VELOCITY METHODS AIMING AT MEASURING AORTIC STIFFNESS. We addressed all the questions and tried to modify the text each time it was possible. We hope that our answers will satisfy the referees.

Left Ventricle Replacement Fibrosis Detected by CMR Associated With Cardiovascular Events in Systemic Sclerosis Patients

Cardiac involvement is the leading cause of death in systemic sclerosis (SSc), although the condition may remain clinically asymptomatic for a long time [(1)][1]. SSc remains underdiagnosed despite repeated transthoracic echocardiography (TTE). This prospective longitudinal study included all

LEFT ATRIAL SIZE : DETERMINANTS USING NON-CONSTRAST ENHANCED CARDIAC COMPUTED TOMOGRAPHY

Objective: Left atrial (LA) size is a marker of diastolic dysfonction and is associated with cardio-vascular outcomes. A new method using a non contrast-enhanced cardiac computed tomography realised for the quantification of coronary artery calcium (CAC) allows to mesure left atrial volume. The aim of this study was to determine the cardio-vascular risks factors associated with left atrial enlargement. Design and method: 458 participants (mean age 59,4 years, 45,4%of women) at intermediate cardio-vascular risk benefited from a non contrast-enhaced cardiac computed tomography. Left atrial volume was performed by countouring the inner edges of LA in three shots of space. Results: Mean LA volume was 76,7 ± 18,6 mL and 41,6 ± 10 mL/m2 after adjustement with body area. Women had significatively largest LA volume (p < 0,0001). LA volume was strongly associated with body mass index and body area (bêta coefficient = 0,27 et p < 0,0001 for both). Obesity (BMI > 30 kg/m2) was correleted with largest LA volume (p < 0,0001). Systolic blood pressure was associated with LA volume and adjusted LA volume (p respectively < 0,01 et 0,01) but the association with hypertension was only found with non adjusted LA volume (p = 0,003). Dyslipidemia was correleted with smaller LA (p < 0,01). Smoking, diabetes and CAC was not associated with LA size. In a fully adjusted model, hypertension, female sex and dyslipidemia was still associated with adjusted LA volume. Conclusions: LA volume determined using non contrast-enhanced computed tomography is associated with BMI, hypertension, female sex and dyslipidemia. This new technique allows to mesure left atrial volume on a cardiac computed tomography used for the assessment of CAC to better predict the cardiovascular risk.

Myocardial Stiffness Evaluation Using Noninvasive Shear Wave Imaging in Healthy and Hypertrophic Cardiomyopathic Adults

Objectives The goal of our study was to investigate the potential of myocardial shear wave imaging (SWI) to quantify the diastolic myocardial stiffness (MS) (kPa) noninvasively in adult healthy volunteers (HVs) and its physiological variation with age, and in hypertrophic cardiomyopathy (HCM) populations with heart failure and preserved ejection function (HFpEF). Background MS is an important prognostic and diagnostic parameter of the diastolic function. MS is affected by physiological changes but also by pathological alterations of extracellular and cellular tissues. However, the clinical assessment of MS and the diastolic function remains challenging. SWI is a novel ultrasound-based technique that has the potential to provide intrinsic MS noninvasively. Methods We prospectively included 80 adults: 60 HV (divided into 3 groups: 20- to 39-year old patients [n = 20]; 40- to 59-year-old patients [n = 20]; and 60- to 79-year-old patients [n = 20]) and 20 HCM-HFpEF patients. Echocardiography, cardiac magnetic resonance imaging and biological explorations were achieved. MS evaluation was performed using an ultrafast ultrasound scanner with cardiac phased array. The fractional anisotropy of MS was also estimated. Results MS increased significantly with age in the HV group (the mean MS was 2.59 ± 0.58 kPa, 4.70 ± 0.88 kPa, and 6.08 ± 1.06 kPa for the 20- to 40-year-old, 40- to 60-year-old, and 60- to 80-year-old patient groups, respectively; p < 0.01 between each group). MS was significantly higher in HCM-HFpEF patients than in HV patients (mean MS = 12.68 ± 2.91 kPa vs. 4.47 ± 1.68 kPa, respectively; p < 0.01), with a cut-off at 8 kPa (area under the curve = 0.993; sensitivity = 95%, specificity = 100%). The fractional anisotropy was lower in HCM-HFpEF (mean = 0.133 ± 0.073) than in HV (0.238 ± 0.068) (p < 0.01). Positive correlations were found between MS and diastolic parameters in echocardiography (early diastolic peak/early diastolic mitral annular velocity, r = 0.783; early diastolic peak/transmitral flow propagation velocity, r = 0.616; left atrial volume index, r = 0.623) and with fibrosis markers in cardiac magnetic resonance (late gadolinium enhancement, r = 0.804; myocardial T1 pre-contrast, r = 0.711). Conclusions MS was found to increase with age in healthy adults and was significantly higher in HCM-HFpEF patients. Myocardial SWI has the potential to become a clinical tool for the diagnostic of diastolic dysfunction. (Non-invasive Evaluation of Myocardial Stiffness by Elastography [Elasto-Cardio]; NCT02537041)

Systemic right ventricular takotsubo cardiomyopathy

Clémence Vernay, Clément Karsenty*, Alban Redheuil, Gilles Soulat, and Laurence Iserin Adult Congenital Heart Disease Unit, Hôpital Européen Georges Pompidou, 20 Rue Leblanc, 75015 Paris, France; and Service de Radiologie, Hôpital Pitié-Salpêtrière, 47-83 Boulevard de l’Hôpital, 75013 Paris, France * Corresponding author. Tel: 133 156093043, Fax: 133 156096654, Email: clement.karsenty@hotmail.fr † The first two authors contributed equally to the study.

Numerical assessment and comparison of pulse wave velocity methods aiming at measuring aortic stiffness

Pulse waveform analyses have become established components of cardiovascular research. Recently several methods have been proposed as tools to measure aortic pulse wave velocity (aPWV). The carotid-femoral pulse wave velocity (cf-PWV), the current clinical gold standard method for the noninvasive assessment of aPWV, uses the carotid-to-femoral pulse transit time difference (cf-PTT) and an estimated path length to derive cf-PWV. OBJECTIVE The heart-ankle PWV (ha-PWV), brachial-ankle PWV (ba-PWV) and finger-toe (ft-PWV) are also methods presuming to approximate aPWV based on time delays between physiological cardiovascular signals at two locations (~heart-ankle PTT, ha-PTT; ~brachial-ankle PTT, ba-PTT; ~finger-toe PTT, ft-PTT) and a path length typically derived from the subjects height. To test the validity of these methods, we used a detailed 1D arterial network model (143 arterial segments) including the foot and hand circulation. APPROACH The arterial tree dimensions and properties were taken from the literature and completed with data from patient scans. We calculated PTTs with all the methods mentioned above. The calculated PTTs were compared with the aortic PTT (aPTT), which is considered as the absolute reference method in this study. MAIN RESULTS The correlation between methods and aPTT was good and significant, cf-PTT (R 2  =  0.97; P  <  0.001; mean difference 5  ±  2 ms), ha-PTT (R 2  =  0.96; P  <  0.001; 150  ±  23 ms), ba-PTT (R 2  =  0.96; P  <  0.001; 70  ±  13 ms) and ft-PTT (R 2  =  0.95; P  <  0.001; 14  ±  10 ms). Consequently, good correlation was also observed for the PWV values derived with the tested methods, but absolute values differed because of the different path lengths used. SIGNIFICANCE In conclusion, our computer model-based analyses demonstrate that for PWV methods based on peripheral signals, pulse transit time differences closely correlate with the aortic transit time, supporting the use of these methods in clinical practice.

[OP.6B.05] ALDOSTERONE PROMOTES MYOCARDIAL EXTRA-CELLULAR MATRIX REMODELING QUANTIFIED BY MAGNETIC RESONANCE IMAGING IN HUMANS INDEPENDENT FROM THE EFFET OF BLOOD PRESSURE

Objective: Aldosterone is central to homeostasis, blood and extracellular fluid regulation and promotes interstitial myocardial fibrosis directly and through secondary hypertension. Magnetic resonance imaging (MRI) is a sensitive method to non invasively quantify extra cellular matrix changes in vivo using T1 tissue relaxation properties. Our aim was to characterize aldosterone-related intra and extracellular myocardial changes independent from hypertension in relation to ventricular remodeling in humans. Figure. No caption available. Design and method: Twenty consecutive patients with primary hyperaldosteronism (PHA) were matched with 20 patients with essential hypertension (HTN) and 20 patients with Bartter-Gitelman syndrome (BG) matched with 20 healthy controls. Total, intra- and extracellular myocardial mass indexed to body surface area were calculated by MRI in 80 individuals using a double case-controlled design to study the respective effects of aldosterone and blood pressure and compared across groups. Results: Compared to healthy controls, BG patients with hyperaldosteronism but low volemia (cardiac preload) and normal blood pressure showed decreased intracellular mass (36 ± 7.5 vs. 42 ± 8.5 g/m2, p = 0.029) and similar extracellular mass leading to lower total myocardial mass (52 ± 6.6 vs. 58 ± 9.1 g/m2, p = 0.029). Compared to healthy controls, HTN patients without hyperaldosteronism but increased cardiac afterload showed increased intracellular mass (49 ± 7.9 vs. 42 ± 8.5 g/m2, p = 0.03) and similar extracellular mass leading to higher total myocardial mass (64 ± 8.7 vs. 58 ± 9.1 g/m2, p = 0.029). However, PHA patients with hyperaldosteronism associated with higher blood pressure levels demonstrated markedly increased total mass (77 ± 18 vs. 58 ± 9.1 g/m2, p < 0.001) secondary to an increase in both intra (56 ± 16 vs. 42 ± 8.5 g/m2, p = 0.001) and extracellular mass (23 ± 7.6 vs.15.5 ± 5.3 g/m2, p = 0.001) compared to healthy controls and differed from the HTN patients by preferential increase of the extracellular compartment (23 ± 7.6 vs. 15 ± 4.1 g/m2, p = 0.007). Conclusions: Differential effects of aldosterone and blood pressure on intra and extracellular components of the myocardium could be quantified non invasively in humans using MRI. Hyperaldosteronism associated with hypertension leads primarily to myocardial extracellular matrix expansion whereas isolated hypertension leads exclusively to increased intracellular mass.

Transconduit puncture without per-procedural echocardiography in nonfenestrated extracardiac Fontan using a simplified approach guided by electroanatomic mapping

From the Adult Congenital Heart Disease Unit, Cardiology Department, European Hospital Georges Pompidou, Paris, France. 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 A 36-year-old man with double-inlet left ventricle, previous nonfenestrated extracardiac Fontan surgery (Gore-Tex conduit), and epicardial dual-chamber pacemaker was referred for catheter ablation of symptomatic atrial tachycardia. Because the arrhythmia was paroxysmal, general anesthesia, which may limit inducibility, was avoided. Transesophageal echocardiography was also avoided because of the patient’s history of chest radiotherapy. Computed tomography (CT) with 3-dimensional (3D) reconstruction showed the position of the extracardiac conduit (EC) along the lateral

[OP.5B.04] IMPACT OF SIMULTANEOUS CENTRAL BLOOD PRESSURE MEASUREMENTS DURING AORTIC STRAIN MAGNETIC RESONANCE IMAGING.

Objective: Proximal aortic function estimated by Magnetic Resonance Imaging (MRI) is booming to assess aortic diseases as stiffness indices have been shown to be independent predictors of cardiovascular events and mortality. Calculation of aortic distensibility (AD) requires MRI aortic strain data, but also local blood pressure (BP). Because of magnetic field limitations, most MRI studies used Brachial Pulse Pressure (bPP) as a surrogate of Central Pulse Pressure (cPP). New devices allow the estimation of cPP from brachial cuff and are compatible with MRI. Our aim was to evaluate differences in AD assessed using cPP and bPP. Design and method: Brachial and central BP were recorded using a 6 meters hose and the SphygmoCor Xcel device (AtCor Medical, Australia) in 58 volunteers (31 males) during non contrast MRI SSFP acquisition of orthogonal section of the ascending aorta (AA). Cross sectional lumen areas were determined using a fully automated contouring method (ARTFUN software). AD of the AA was defined as (Area_max-Area_min)/(Area_min x PP) with PP = bPP and cPP for AD_b and AD_c respectively. Results: Among the 58 patients, 18(31%) were treated for hypertension, 6(10%) were active smokers, none were diabetic or dyslipidaemic. Median age was 43 years(28–67). AD_c and AD_b were highly correlated (r = 0.986, p < 0.001) with a significant bias across the range leading to underestimation of AD_b (−1.87 ± 1.6610–3 mmHg) for higher AD values (r = −0.94, p < 0.0001, figure 1). The correlation with age was stronger using AD_c (&rgr; = −0.87; p < 0,001) than AD_b (&rgr; = −0.83, p < 0.001). AD difference between the 2-age quantiles was higher when using AD_c (−7.08 ± 0.56; p < 0,001) compared to AD_b (−4.26 ± 0.38, p < 0.001, figure 2). Only in young subjects, AD_c was significantly higher than AD_b (p < 0,0001). Figure. No caption available. Conclusions: Using cPP instead of bPP leads to differences in MRI assessment of AD especially in younger subjects. bPP might not be suitable as a surrogate measure of ascending aortic PP for AD assessment. The use of cPP improves aortic stiffness MRI assessment and may be useful to detect early aortic function impairment in young patients.